CALIFORNIA STANDARD PRACTICE MANUAL
ECONOMIC ANALYSIS OF DEMAND-SIDE
PROGRAMS AND PROJECTS
OCTOBER 2001
1
Table of Contents
Page
Chapter 1 .............................................................................................................................. 1
Basic Methodology ............................................................................................................... 1
Background....................................................................................................................... 1
Demand-Side Management Categories and Program Definitions.......................................2
Basic Methods .................................................................................................................. 4
Balancing the Tests ........................................................................................................... 6
Limitations: Externality Values and Policy Rules.............................................................. 6
Externality Values............................................................................................................. 7
Policy Rules......................................................................................................................7
Chapter 2 .............................................................................................................................. 8
Participant Test ..................................................................................................................... 8
Definition.......................................................................................................................... 8
Benefits and Costs............................................................................................................. 8
How the Results Can be Expressed....................................................................................9
Strengths of the Participant Test........................................................................................ 9
Weaknesses of the Participant Test.................................................................................. 10
Formulae......................................................................................................................... 10
Chapter 3 ............................................................................................................................ 13
The Ratepayer Impact Measure Test ................................................................................... 13
Definition........................................................................................................................ 13
Benefits and Costs........................................................................................................... 13
How the Results can be Expressed .................................................................................. 13
Strengths of the Ratepayer Impact Measure (RIM) Test .................................................. 14
Weaknesses of the Ratepayer Impact Measure (RIM) Test .............................................. 15
Chapter 4 ............................................................................................................................ 18
Total Resource Cost Test .................................................................................................... 18
Definition........................................................................................................................ 18
How the Results Can be Expressed.................................................................................. 19
Strengths of the Total Resource Cost Test ....................................................................... 21
Weakness of the Total Resource Cost Test ...................................................................... 21
Formulas......................................................................................................................... 21
Chapter 5 ............................................................................................................................ 23
Program Administrator Cost Test........................................................................................ 23
Definition........................................................................................................................ 23
Benefits and Costs........................................................................................................... 23
How the Results Can be Expressed.................................................................................. 23
Strengths of the Program Administrator Cost Test........................................................... 24
Weaknesses of the Program Administrator Cost Test....................................................... 24
Formulas......................................................................................................................... 24
Appendix A ........................................................................................................................ 26
Inputs to Equations and Documentation .............................................................................. 26
Appendix B......................................................................................................................... 28
2
Summary of Equations and Glossary of Symbols ................................................................ 28
Basic Equations............................................................................................................... 28
Participant Test ........................................................................................................... 28
Ratepayer Impact Measure Test................................................................................... 28
Total Resource Cost Test............................................................................................. 28
Program Administrator Cost Test ................................................................................ 28
Benefits and Costs........................................................................................................... 29
Participant Test ........................................................................................................... 29
Ratepayer Impact Measure Test................................................................................... 29
Total Resource Cost Test............................................................................................. 29
Program Administrator Cost Test ................................................................................ 30
Glossary of Symbols ....................................................................................................... 30
Appendix C......................................................................................................................... 33
Derivation of Rim Lifecycle Revenue Impact Formula........................................................ 33
Rate Impact Measure....................................................................................................... 33
1
Chapter 1
Basic Methodology
Background
Since the 1970s, conservation and load management programs have been promoted by the
California Public Utilities Commission (CPUC) and the California Energy Commission
(CEC) as alternatives to power plant construction and gas supply options. Conservation and
load management (C&LM) programs have been implemented in California by the major
utilities through the use of ratepayer money and by the CEC pursuant to the CEC legislative
mandate to establish energy efficiency standards for new buildings and appliances.
While cost-effectiveness procedures for the CEC standards are outlined in the Public
Resources Code, no such official guidelines existed for utility-sponsored programs. With the
publication of the Standard Practice for Cost-Benefit Analysis of Conservation and Load
Management Programs in February 1983, this void was substantially filled. With the
informal "adoption" one year later of an appendix that identified cost-effectiveness
procedures for an "All Ratepayers" test, C&LM program cost effectiveness consisted of the
application of a series of tests representing a variety of perspectives-participants, non-
participants, all ratepayers, society, and the utility.
The Standard Practice Manual was revised again in 1987-88. The primary changes (relative
to the 1983 version), were: (1) the renaming of the “Non-Participant Test” to the “Ratepayer
Impact Test“; (2) renaming the All-Ratepayer Test” to the “Total Resource Cost Test.”; (3)
treating the “Societal Test” as a variant of the “Total Resource Cost Test;” and, (4) an
expanded explanation of “demand-side” activities that should be subjected to standard
procedures of benefit-cost analysis.
Further changes to the manual captured in this (2001) version were prompted by the
cumulative effects of changes in the electric and natural gas industries and a variety of
changes in California statute related to these changes. As part of the major electric industry
restructuring legislation of 1996 (AB1890), for example, a public goods charge was
established that ensured minimum funding levels for “cost effective conservation and energy
efficiency” for the 1998-2002 period, and then (in 2000) extended through the year 2011.
Additional legislation in 2000 (AB1002) established a natural gas surcharge for similar
purposes. Later in that year, the Energy Security and Reliability Act of 2000 (AB970)
directed the California Public Utilities Commission to establish, by the Spring of 2001, a
distribution charge to provide revenues for a self generation program and a directive to
consider changes to cost-effectiveness methods to better account for reliability concerns.
In the Spring of 2001, a new state agency — the Consumer Power and Conservation
Financing Authority — was created. This agency is expected to provide additional revenues
in the form of state revenue bonds that could supplement the amount and type of public
financial resources to finance energy efficiency and self generation activities.
2
The modifications to the Standard Practice Manual reflect these more recent developments in
several ways. First, the “Utility Cost Test” is renamed the “Program Administrator Test” to
include the assessment of programs managed by other agencies. Second, a definition of self
generation as a type of “demand-side” activity is included. Third, the description of the
various potential elements of “externalities” in the Societal version of the TRC test is
expanded. Finally the limitations section outlines the scope of this manual and elaborates
upon the processes traditionally instituted by implementing agencies to adopt values for these
externalities and to adopt the the policy rules that accompany this manual.
Demand-Side Management Categories and Program
Definitions
One important aspect of establishing standardized procedures for cost-effectiveness
evaluations is the development and use of consistent definitions of categories, programs, and
program elements.
This manual employs the use of general program categories that distinguish between
different types of demand-side management programs, conservation, load management, fuel
substitution, load building and self-generation. Conservation programs reduce electricity
and/or natural gas consumption during all or significant portions of the year. ‘Conservation’
in this context includes all ‘energy efficiency improvements’. An energy efficiency
improvement can be defined as reduced energy use for a comparable level of service,
resulting from the installation of an energy efficiency measure or the adoption of an energy
efficiency practice. Level of service may be expressed in such ways as the volume of a
refrigerator, temperature levels, production output of a manufacturing facility, or lighting
level per square foot. Load management programs may either reduce electricity peak
demand or shift demand from on peak to non-peak periods.
Fuel substitution and load building programs share the common feature of increasing annual
consumption of either electricity or natural gas relative to what would have happened in the
absence of the program. This effect is accomplished in significantly different ways, by
inducing the choice of one fuel over another (fuel substitution), or by increasing sales of
electricity, gas, or electricity and gas (load building). Self generation refers to distributed
generation (DG) installed on the customer’s side of the electric utility meter, which serves
some or all of the customer's electric load, that otherwise would have been provided by the
central electric grid.
In some cases, self generation products are applied in a combined heat and power manner, in
which case the heat produced by the self generation product is used on site to provide some
or all of the customer’s thermal needs. Self generation technologies include, but are not
limited to, photovoltaics, wind turbines, fuel cells, microturbines, small gas-fired turbines,
and gas-fired internal combustion engines.
Fuel substitution and load building programs were relatively new to demand-side
management in California in the late 1980s, born out of the convergence of several factors
3
that translated into average rates that substantially exceeded marginal costs. Proposals by
utilities to implement programs that increase sales had prompted the need for additional
procedures for estimating program cost effectiveness. These procedures maybe applicable in
a new context. AB 970 amended the Public Utilities Code and provided the motivation to
develop a cost-effectiveness method that can be used on a common basis to evaluate all
programs that will remove electric load from the centralized grid, including energy
efficiency, load control/demand-responsiveness programs and self-generation. Hence, self-
generation was also added to the list of demand side management programs for cost-
effectiveness evaluation. In some cases, self-generation programs installed with incremental
load are also included since the definition of self-generation is not necessarily confined to
projects that reduce electric load on the grid. For example, suppose an industrial customer
installs a new facility with a peak consumption of 1.5 MW, with an integrated on-site
1.0 MW gas fired DG unit. The combined impact of the new facility is load building since
the new facility can draw up to 0.5 MW from the grid, even when the DG unit is running.
The proper characterization of each type of demand-side management program is essential to
ensure the proper treatment of inputs and the appropriate interpretation of cost-effectiveness
results.
Categorizing programs is important because in many cases the same specific device can be
and should be evaluated in more than one category. For example, the promotion of an electric
heat pump can and should be treated as part of a conservation program if the device is
installed in lieu of a less efficient electric resistance heater. If the incentive induces the
installation of an electric heat pump instead of gas space heating, however, the program
needs to be considered and evaluated as a fuel substitution program. Similarly, natural gas-
fired self-generation, as well as self-generation units using other non-renewable fossil fuels,
must be treated as fuel-substitution. In common with other types of fuel-substitution, any
costs of gas transmission and distribution, and environmental externalities, must be
accounted for. In addition, cost-effectiveness analyses of self-generation should account for
utility interconnection costs. Similarly, a thermal energy storage device should be treated as a
load management program when the predominant effect is to shift load. If the acceptance of a
utility incentive by the customer to, install the energy storage device is a decisive aspect of
the customer's decision to remain an electric utility customer (i.e., to reject or defer the
option of installing a gas-fired cogeneration system), then the predominant effect of the
thermal energy storage device has been to substitute electricity service for the natural gas
service that would have occurred in the absence of the program.
In addition to Fuel Substitution and Load Building Programs, recent utility program
proposals have included reference to "load retention," "sales retention," "market retention,"
or "customer retention" programs. In most cases, the effect of such programs is identical to
either a Fuel Substitution or a Load Building program — sales of one fuel are increased
relative to sales without the program. A case may be made, however, for defining a separate
category of program called "load retention." One unambiguous example of a load retention
program is the situation where a program keeps a customer from relocating to another utility
service area. However, computationally the equations and guidelines included in this manual
to accommodate Fuel Substitution and Load Building programs can also handle this special
situation as well.
4
Basic Methods
This manual identifies the cost and benefit components and cost-effectiveness calculation
procedures from four major perspectives: Participant, Ratepayer Impact Measure (RIM),
Program Administrator Cost (PAC), and Total Resource Cost (TRC). A fifth perspective, the
Societal, is treated as a variation on the Total Resource Cost test. The results of each
perspective can be expressed in a variety of ways, but in all cases it is necessary to calculate
the net present value of program impacts over the lifecycle of those impacts.
Table I summarizes the cost-effectiveness tests addressed in this manual. For each of the
perspectives, the table shows the appropriate means of expressing test results. The primary
unit of measurement refers to the way of expressing test results that are considered by the
staffs of the two Commissions as the most useful for summarizing and comparing demand-
side management (DSM) program cost-effectiveness. Secondary indicators of cost-
effectiveness represent supplemental means of expressing test results that are likely to be of
particular value for certain types of proceedings, reports, or programs.
This manual does not specify how the cost-effectiveness test results are to be displayed or the
level at which cost-effectiveness is to be calculated (e.g., groups of programs, individual
programs, and program elements for all or some programs). It is reasonable to expect
different levels and types of results for different regulatory proceedings or for different
phases of the process used to establish proposed program-funding levels. For example, for
summary tables in general rate case proceedings at the CPUC, the most appropriate tests may
be the RIM lifecycle revenue impact, Total Resource Cost, and Program Administrator Cost
test results for programs or groups of programs. The analysis and review of program
proposals for the same proceeding may include Participant test results and various additional
indicators of cost-effectiveness from all tests for each individual program element. In the
case of cost-effectiveness evaluations conducted in the context of integrated long-term
resource planning activities, such detailed examination of multiple indications of costs and
benefits may be impractical.
5
Table I
Cost-Effectiveness Tests
Participant
Primary
Secondary
Net present value (all participants)
Discounted payback (years)
Benefit-cost ratio
Net present value (average participant)
Ratepayer Impact Measure
Lifecycle revenue impact per Unit of
energy (kWh or therm) or demand
customer (kW)
Net present value
Lifecycle revenue impact per unit
Annual revenue impact (by year, per
kWh, kW, therm, or customer)
First-year revenue impact (per kWh, kW,
therm, or customer)
Benefit-cost ratio
Total Resource Cost
Net present value (NPV)
Benefit-cost ratio (BCR)
Levelized cost (cents or dollars per unit
of energy or demand)
Societal (NPV, BCR)
Program Administrator Cost
Net present value
Benefit-cost ratio
Levelized cost (cents or dollars per unit
of energy or demand)
Rather than identify the precise requirements for reporting cost-effectiveness results for all
types of proceedings or reports, the approach taken in this manual is to (a) specify the
components of benefits and costs for each of the major tests, (b) identify the equations to be
used to express the results in acceptable ways; and (c) indicate the relative value of the
different units of measurement by designating primary and secondary test results for each
test.
It should be noted that for some types of demand-side management programs, meaningful
cost-effectiveness analyses cannot be performed using the tests in this manual. The following
guidelines are offered to clarify the appropriated "match" of different types of programs and
tests:
1. For generalized information programs (e.g., when customers are provided generic
information on means of reducing utility bills without the benefit of on-site
evaluations or customer billing data), cost-effectiveness tests are not expected
because of the extreme difficulty in establishing meaningful estimates of load
impacts.
6
2. For any program where more than one fuel is affected, the preferred unit of
measurement for the RIM test is the lifecycle revenue impacts per customer, with gas
and electric components reported separately for each fuel type and for combined
fuels.
3. For load building programs, only the RIM tests are expected to be applied. The Total
Resource Cost and Program Administrator Cost tests are intended to identify cost-
effectiveness relative to other resource options. It is inappropriate to consider
increased load as an alternative to other supply options.
4. Levelized costs may be appropriate as a supplementary indicator of cost per unit for
electric conservation and load management programs relative to generation options
and gas conservation programs relative to gas supply options, but the levelized cost
test is not applicable to fuel substitution programs (since they combine gas and
electric effects) or load building programs (which increase sales).
The delineation of the various means of expressing test results in Table 1 is not meant to
discourage the continued development of additional variations for expressing cost-
effectiveness. Of particular interest is the development of indicators of program cost
effectiveness that can be used to assess the appropriateness of program scope (i.e. level of
funding) for General Rate Case proceedings. Additional tests, if constructed from the net
present worth in conformance with the equations designated in this manual, could prove
useful as a means of developing methodologies that will address issues such as the optimal
timing and scope of demand-side management programs in the context of overall resource
planning.
Balancing the Tests
The tests set forth in this manual are not intended to be used individually or in isolation. The
results of tests that measure efficiency, such as the Total Resource Cost Test, the Societal
Test, and the Program Administrator Cost Test, must be compared not only to each other but
also to the Ratepayer Impact Measure Test. This multi-perspective approach will require
program administrators and state agencies to consider tradeoffs between the various tests.
Issues related to the precise weighting of each test relative to other tests and to developing
formulas for the definitive balancing of perspectives are outside the scope of this manual.
The manual, however, does provide a brief description of the strengths and weaknesses of
each test (Chapters 2, 3, 4, and 5) to assist users in qualitatively weighing test results.
Limitations: Externality Values and Policy Rules
The list of externalities identified in Chapter 4, page 27, in the discussion on the Societal
version of the Total Resource Cost test is broad, illustrative and by no means exhaustive.
Traditionally, implementing agencies have independently determined the details such as the
components of the externalities, the externality values and the policy rules which specify the
contexts in which the externalities and the tests are used.
7
Externality Values
The values for the externalities have not been provided in the manual. There are separate
studies and methodologies to arrive at these values. There are also separate processes
instituted by implementing agencies before such values can be adopted formally.
Policy Rules
The appropriate choice of inputs and input components vary by program area and project.
For instance, low income programs are evaluated using a broader set of non-energy benefits
that have not been provided in detail in this manual. Implementing agencies traditionally
have had the discretion to use or to not use these inputs and/or benefits on a project- or
program-specific basis. The policy rules that specify the contexts in which it is appropriate to
use the externalities, their components, and tests mentioned in this manual are an integral part
of any cost-effectiveness evaluation. These policy rules are not a part of this manual.
To summarize, the manual provides the methodology and the cost-benefit calculations only.
The implementing agencies (such as the California Public Utilities Commission and the
California Energy Commission) have traditionally utilized open public processes to
incorporate the diverse views of stakeholders before adopting externality values and policy
rules which are an integral part of the cost-effectiveness evaluation.
8
Chapter 2
Participant Test
Definition
The Participants Test is the measure of the quantifiable benefits and costs to the customer
due to participation in a program. Since many customers do not base their decision to
participate in a program entirely on quantifiable variables, this test cannot be a complete
measure of the benefits and costs of a program to a customer.
Benefits and Costs
The benefits of participation in a demand-side program include the reduction in the
customer's utility bill(s), any incentive paid by the utility or other third parties, and any
federal, state, or local tax credit received. The reductions to the utility bill(s) should be
calculated using the actual retail rates that would have been charged for the energy service
provided (electric demand or energy or gas). Savings estimates should be based on gross
savings, as opposed to net energy savings
1
.
In the case of fuel substitution programs, benefits to the participant also include the avoided
capital and operating costs of the equipment/appliance not chosen. For load building
programs, participant benefits include an increase in productivity and/or service, which is
presumably equal to or greater than the productivity/ service without participating. The
inclusion of these benefits is not required for this test, but if they are included then the
societal test should also be performed.
The costs to a customer of program participation are all out-of-pocket expenses incurred as a
result of participating in a program, plus any increases in the customer's utility bill(s). The
out-of-pocket expenses include the cost of any equipment or materials purchased, including
sales tax and installation; any ongoing operation and maintenance costs; any removal costs
(less salvage value); and the value of the customer's time in arranging for the installation of
the measure, if significant.
1
Gross energy savings are considered to be the savings in energy and demand seen by the participant at the
meter. These are the appropriate program impacts to calculate bill reductions for the Participant Test. Net
savings are assumed to be the savings that are attributable to the program. That is, net savings are gross savings
minus those changes in energy use and demand that would have happened even in the absence of the program.
For fuel substitution and load building programs, gross-to-net considerations account for the impacts that would
have occurred in the absence of the program.
9
How the Results can be Expressed
The results of this test can be expressed in four ways: through a net present value per average
participant, a net present value for the total program, a benefit-cost ratio or discounted
payback. The primary means of expressing test results is net present value for the total
program; discounted payback, benefit-cost ratio, and per participant net present value are
secondary tests.
The discounted payback is the number of years it takes until the cumulative discounted
benefits equal or exceed the cumulative discounted costs. The shorter the discounted
payback, the more attractive or beneficial the program is to the participants. Although
"payback period" is often defined as undiscounted in the textbooks, a discounted payback
period is used here to approximate more closely the consumer's perception of future benefits
and costs.
2
Net present value (NPVp) gives the net dollar benefit of the program to an average
participant or to all participants discounted over some specified time period. A net present
value above zero indicates that the program is beneficial to the participants under this test.
The benefit-cost ratio (BCRp) is the ratio of the total benefits of a program to the total costs
discounted over some specified time period. The benefit-cost ratio gives a measure of a
rough rate of return for the program to the participants and is also an indication of risk. A
benefit-cost ratio above one indicates a beneficial program.
Strengths of the Participant Test
The Participants Test gives a good "first cut" of the benefit or desirability of the program to
customers. This information is especially useful for voluntary programs as an indication of
potential participation rates.
For programs that involve a utility incentive, the Participant Test can be used for program
design considerations such as the minimum incentive level, whether incentives are really
needed to induce participation, and whether changes in incentive levels will induce the
desired amount of participation.
These test results can be useful for program penetration analyses and developing program
participation goals, which will minimize adverse ratepayer impacts and maximize benefits.
For fuel substitution programs, the Participant Test can be used to determine whether
program participation (i.e. choosing one fuel over another) will be in the long-run best
interest of the customer. The primary means of establishing such assurances is the net present
value, which looks at the costs and benefits of the fuel choice over the life of the equipment.
2
It should be noted that if a demand-side program is beneficial to its participants (NPVp > 0 and BCRp > 1.0)
using a particular discount rate, the program has an internal rate of return (IRR) of at least the value of the
discount rate.
10
Weaknesses of the Participant Test
None of the Participant Test results (discounted payback, net present value, or benefit-cost
ratio) accurately capture the complexities and diversity of customer decision-making
processes for demand-side management investments. Until or unless more is known about
customer attitudes and behavior, interpretations of Participant Test results continue to require
considerable judgment. Participant Test results play only a supportive role in any assessment
of conservation and load management programs as alternatives to supply projects.
Formulae
The following are the formulas for discounted payback, the net present value (NPVp) and the
benefit-cost ratio (BCRp) for the Participant Test.
NPV
P
= Bp - Cp
NPVavp = (Bp - Cp) / P
BCRp = Bp / Cp
DPp = Min j such that Bj > Cj
Where:
NPVp = Net present value to all participants
NPVavp = Net present value to the average participant
BCRp = Benefit-cost ratio to participants
DPp = Discounted payback in years
Bp = NPV of benefit to participants
Cp = NPV of costs to participants
Bj = Cumulative benefits to participants in year j
Cj = Cumulative costs to participants in year j
P = Number of program participants
J = First year in which cumulative benefits are cumulative costs.
d = Interest rate (discount)
The Benefit (Bp) and Cost (Cp) terms are further defined as follows:
!
=
"
+
++
=
N
t
t
ttt
d
INCTCBR
BP
1
1
)1(
+
!
=
"
+
+
N
t
t
atat
d
PAAB
1
1
)1(
!
=
"
+
+
=
N
t
t
tt
d
BIPC
C
1
1
)1(
Where:
BRt = Bill reductions in year t
Bit = Bill increases in year t
11
TCt = Tax credits in year t
INCt = Incentives paid to the participant by the sponsoring utility in year t
3
PCt = Participant costs in year t to include:
Initial capital costs, including sales tax
4
Ongoing operation and maintenance costs include fuel cost
Removal costs, less salvage value
Value of the customer's time in arranging for installation, if
significant
PACat = Participant avoided costs in year t for alternate fuel devices (costs of
devices not chosen)
Abat = Avoided bill from alternate fuel in year t
The first summation in the Bp equation should be used for conservation and load
management programs. For fuel substitution programs, both the first and second summations
should be used for Bp.
Note that in most cases, the customer bill impact terms (BRt, BIt, and AB
at
) are further
determined by costing period to reflect load impacts and/or rate schedules, which vary
substantially by time of day and season. The formulas for these variables are as follows:
! !
= =
+""#+""#=
I
i
I
i
tititititititt
OBRKDACDGKEACEGBR
1 1
):():(
AB
at
= (Use BRt formula, but with rates and costing periods appropriate for the alternate
fuel utility)
! !
= =
+"##$+"##$=
I
i
I
i
tititititititt
OBIKDACDGKEACEGBI
1 1
))1(:())1(:(
Where:
ΔEG
it
= Reduction in gross energy use in costing period i in year t
ΔDG
it
= Reduction in gross billing demand in costing period i in year t
AC:E
it
= Rate charged for energy in costing period i in year t
3
Some difference of opinion exists as to what should be called an incentive. The term can be interpreted
broadly to include almost anything. Direct rebates, interest payment subsidies, and even energy audits can be
called incentives. Operationally, it is necessary to restrict the term to include only dollar benefits such as rebates
or rate incentives (monthly bill credits). Information and services such as audits are not considered incentives
for the purposes of these tests. If the incentive is to offset a specific participant cost, as in a rebate-type
incentive, the full customer cost (before the rebate must be included in the PC
t
term
4
If money is borrowed by the customer to cover this cost, it may not be necessary to calculate the annual
mortgage and discount this amount if the present worth of the mortgage payments equals the initial cost. This
occurs when the discount rate used is equal to the interest rate of the mortgage. If the two rates differ (e.g., a
loan offered by the utility), then the stream of mortgage payments should be discounted by the discount rate
chosen.
12
AC:D
it
= Rate charged for demand in costing period i in year t
K
it
= 1 when ΔEGit or ΔDGit is positive (a reduction) in costing period i in
year t, and zero otherwise
OBR
t
= Other bill reductions or avoided bill payments (e.g.,, customer charges,
standby rates).
OBI
t
= Other bill increases (i.e. customer charges, standby rates).
I = Number of periods of participant’s participation
In load management programs such as TOU rates and air-conditioning cycling, there are
often no direct customer hardware costs. However, attempts should be made to quantify
indirect costs customers may incur that enable them to take advantage of TOU rates and
similar programs.
If no customer hardware costs are expected or estimates of indirect costs and value of service
are unavailable, it may not be possible to calculate the benefit-cost ratio and discounted
payback period.
13
Chapter 3
The Ratepayer Impact Measure Test
5
Definition
The Ratepayer Impact Measure (RIM) test measures what happens to customer bills or rates
due to changes in utility revenues and operating costs caused by the program. Rates will go
down if the change in revenues from the program is greater than the change in utility costs.
Conversely, rates or bills will go up if revenues collected after program implementation are
less than the total costs incurred by the utility in implementing the program. This test
indicates the direction and magnitude of the expected change in customer bills or rate levels.
Benefits and Costs
The benefits calculated in the RIM test are the savings from avoided supply costs. These
avoided costs include the reduction in transmission, distribution, generation, and capacity
costs for periods when load has been reduced and the increase in revenues for any periods in
which load has been increased. The avoided supply costs are a reduction in total costs or
revenue requirements and are included for both fuels for a fuel substitution program. The
increase in revenues are also included for both fuels for fuel substitution programs. Both the
reductions in supply costs and the revenue increases should be calculated using net energy
savings.
The costs for this test are the program costs incurred by the utility, and/or other entities
incurring costs and creating or administering the program, the incentives paid to the
participant, decreased revenues for any periods in which load has been decreased and
increased supply costs for any periods when load has been increased. The utility program
costs include initial and annual costs, such as the cost of equipment, operation and
maintenance, installation, program administration, and customer dropout and removal of
equipment (less salvage value). The decreases in revenues and the increases in the supply
costs should be calculated for both fuels for fuel substitution programs using net savings.
How the Results can be Expressed
The results of this test can be presented in several forms: the lifecycle revenue impact (cents
or dollars) per kWh, kW, therm, or customer; annual or first-year revenue impacts (cents or
dollars per kWh, kW, therms, or customer); benefit-cost ratio; and net present value. The
primary units of measurement are the lifecycle revenue impact, expressed as the change in
rates (cents per kWh for electric energy, dollars per kW for electric capacity, cents per therm
for natural gas) and the net present value. Secondary test results are the lifecycle revenue
5
The Ratepayer Impact Measure Test has previously been described under what was called the
"Non-Participant Test." The Non-Participant Test has also been called the "Impact on Rate Levels Test."
14
impact per customer, first-year and annual revenue impacts, and the benefit-cost ratio.
LRI
RIM
values for programs affecting electricity and gas should be calculated for each fuel
individually (cents per kWh or dollars per kW and cents per therm) and on a combined gas
and electric basis (cents per customer).
The lifecycle revenue impact (LRI) is the one-time change in rates or the bill change over the
life of the program needed to bring total revenues in line with revenue requirements over the
life of the program. The rate increase or decrease is expected to be put into effect in the first
year of the program. Any successive rate changes such as for cost escalation are made from
there. The first-year revenue impact (FRI) is the change in rates in the first year of the
program or the bill change needed to get total revenues to match revenue requirements only
for that year. The annual revenue impact (ARI) is the series of differences between revenues
and revenue requirements in each year of the program. This series shows the cumulative rate
change or bill change in a year needed to match revenues to revenue requirements. Thus, the
ARIRIM for year six per kWh is the estimate of the difference between present rates and the
rate that would be in effect in year six due to the program. For results expressed as lifecycle,
annual, or first-year revenue impacts, negative results indicate favorable effects on the bills
of ratepayers or reductions in rates. Positive test result values indicate adverse bill impacts or
rate increases.
Net present value (NPV
RIM
) gives the discounted dollar net benefit of the program from the
perspective of rate levels or bills over some specified time period. A net present value above
zero indicates that the program will benefit (lower) rates and bills.
The benefit-cost ratio (BCR RIM) is the ratio of the total benefits of a program to the total
costs discounted over some specified time period. A benefit-cost ratio above one indicates
that the program will lower rates and bills.
Strengths of the Ratepayer Impact Measure (RIM)
Test
In contrast to most supply options, demand-side management programs cause a direct shift in
revenues. Under many conditions, revenues lost from DSM programs have to be made up by
ratepayers. The RIM test is the only test that reflects this revenue shift along with the other
costs and benefits associated with the program.
An additional strength of the RIM test is that the test can be used for all demand-side
management programs (conservation, load management, fuel substitution, and load building).
This makes the RIM test particularly useful for comparing impacts among demand-side
management options.
Some of the units of measurement for the RIM test are of greater value than others,
depending upon the purpose or type of evaluation. The lifecycle revenue impact per customer
is the most useful unit of measurement when comparing the merits of programs with highly
variable scopes (e.g.,, funding levels) and when analyzing a wide range of programs that
15
include both electric and natural gas impacts. Benefit-cost ratios can also be very useful for
program design evaluations to identify the most attractive programs or program elements.
If comparisons are being made between a program or group of conservation/load
management programs and a specific resource project, lifecycle cost per unit of energy and
annual and first-year net costs per unit of energy are the most useful way to express test
results. Of course, this requires developing lifecycle, annual, and first-year revenue impact
estimates for the supply-side project.
Weaknesses of the Ratepayer Impact Measure (RIM)
Test
Results of the RIM test are probably less certain than those of other tests because the test is
sensitive to the differences between long-term projections of marginal costs and long-term
projections of rates, two cost streams that are difficult to quantify with certainty.
RIM test results are also sensitive to assumptions regarding the financing of program costs.
Sensitivity analyses and interactive analyses that capture feedback effects between system
changes, rate design options, and alternative means of financing generation and non-
generation options can help overcome these limitations. However, these types of analyses
may be difficult to implement.
An additional caution must be exercised in using the RIM test to evaluate a fuel substitution
program with multiple end use efficiency options. For example, under conditions where
marginal costs are less than average costs, a program that promotes an inefficient appliance
may give a more favorable test result than a program that promotes an efficient appliance.
Though the results of the RIM test accurately reflect rate impacts, the implications for long-
term conservation efforts need to be considered.
Formulae: The formulae for the lifecycle revenue impact (LRI RIM)' net present value
(NPV RIM), benefit-cost ratio (BCR RIM)' the first-year revenue impacts and annual
revenue impacts are presented below:
LRIRIM = (CRIM - BRIM) / E
FRIRIM = (CRIM - BRIM) / E for t = I
ARIRIMt = FRIRIM for t = I
= (CRIMt - BRIMt )/Et for t=2, ………….., N
NPVRIM = BRIM-CRIM
BCRRIM` = BRIM/CRIM where:
LRIRIM = Lifecycle revenue impact of the program per unit of energy (kWh or therm)
or demand (kW) (the one-time change in rates) or per customer (the change
in customer bills over the life of the program). (Note: An appropriate
choice of kWh, therm, kW, and customer should be made)
16
FRIRIM = First-year revenue impact of the program per unit of energy, demand, or
per customer.
ARIRIM = Stream of cumulative annual revenue impacts of the program per unit of
energy, demand, or per customer. (Note: The terms in the ARI formula are
not discounted; thus they are the nominal cumulative revenue impacts.
Discounted cumulative revenue impacts may be calculated and submitted if
they are indicated as such. Note also that the sum of the discounted stream
of cumulative revenue impacts does not equal the LRI RIM')
NPVRIM = Net present value levels
BCRRIM = Benefit-cost ratio for rate levels
BRIM = Benefits to rate levels or customer bills
CRIM = Costs to rate levels or customer bills
E = Discounted stream of system energy sales (kWh or therms) or demand sales
(kW) or first-year customers. (See Appendix D for a description of the
derivation and use of this term in the LRIRIM test.)
The B
RIM
and C
RIM
terms are further defined as follows:
!!
=
"
=
"
+
+
+
+
N
t
t
at
N
t
t
t
RIM
d
UAC
d
RGUAC
B
t
1
1
1
1
)1()1(
!!
=
"
=
"
+
+
+
+++
N
t
t
at
N
t
t
tttt
RIM
d
RL
d
INCPRCRLUIC
C
1
1
1
1
)1()1(
!
=
"
+
=
N
t
t
t
d
E
E
1
1
)1(
Where:
UACt = Utility avoided supply costs in year t
UICt = Utility increased supply costs in year t
RGt = Revenue gain from increased sales in year t
RLt = Revenue loss from reduced sales in year t
PRCt = Program Administrator program costs in year t
Et = System sales in kWh, kW or therms in year t or first year customers
UACat = Utility avoided supply costs for the alternate fuel in year t
Rlat = Revenue loss from avoided bill payments for alternate fuel in year t (i.e.,
device not chosen in a fuel substitution program)
17
For fuel substitution programs, the first term in the B RIM and C RIM equations represents
the sponsoring utility (electric or gas), and the second term represents the alternate utility.
The RIM test should be calculated separately for electric and gas and combined electric and
gas.
The utility avoided cost terms (UAC
t
, UIC
t
, and UAC
at
) are further determined by costing
period to reflect time-variant costs of supply:
):():(
1 1
ititit
I
i
I
i
itititt
KDMCDNKEMCENUCA !!"+!!"=
# #
= =
UAC
at
= (Use UACt formula, but with marginal costs and costing periods appropriate
for the alternate fuel utility.)
! !
= =
"##$+"##$
I
i
I
i
itititititt
KDMCDNKEMCENUIC
1 1
))1(:())1(:(
Where:
[Only terms not previously defined are included here.]
ΔENit = Reduction in net energy use in costing period i in year t
ΔDNit = Reduction in net demand in costing period i in year t
MC:Eit = Marginal cost of energy in costing period i in year t
MC:Dit = Marginal cost of demand in costing period i in year t
The revenue impact terms (RG
t
, RL
t
, and RL
at
) are parallel to the bill impact terms in the
Participant Test. The terms are calculated exactly the same way with the exception that the
net impacts are used rather than gross impacts. If a net-to-gross ratio is used to differentiate
gross savings from net savings, the revenue terms and the participant's bill terms will be
related as follows:
RGt = BIt * (net-to-gross ratio)
RLt = BRt * (net-to-gross ratio)
Rlat = Abat * (net-to-gross ratio)
18
Chapter 4
Total Resource Cost Test
6
Definition
The Total Resource Cost Test measures the net costs of a demand-side management program
as a resource option based on the total costs of the program, including both the participants'
and the utility's costs.
The test is applicable to conservation, load management, and fuel substitution programs. For
fuel substitution programs, the test measures the net effect of the impacts from the fuel not
chosen versus the impacts from the fuel that is chosen as a result of the program. TRC test
results for fuel substitution programs should be viewed as a measure of the economic
efficiency implications of the total energy supply system (gas and electric).
A variant on the TRC test is the Societal Test. The Societal Test differs from the TRC test in
that it includes the effects of externalities (e.g.,, environmental, national security), excludes
tax credit benefits, and uses a different (societal) discount rate.
Benefits and Costs: This test represents the combination of the effects of a program on both
the customers participating and those not participating in a program. In a sense, it is the
summation of the benefit and cost terms in the Participant and the Ratepayer Impact Measure
tests, where the revenue (bill) change and the incentive terms intuitively cancel (except for
the differences in net and gross savings).
The benefits calculated in the Total Resource Cost Test are the avoided supply costs, the
reduction in transmission, distribution, generation, and capacity costs valued at marginal cost
for the periods when there is a load reduction. The avoided supply costs should be calculated
using net program savings, savings net of changes in energy use that would have happened in
the absence of the program. For fuel substitution programs, benefits include the avoided
device costs and avoided supply costs for the energy, using equipment not chosen by the
program participant.
The costs in this test are the program costs paid by both the utility and the participants plus
the increase in supply costs for the periods in which load is increased. Thus all equipment
costs, installation, operation and maintenance, cost of removal (less salvage value), and
administration costs, no matter who pays for them, are included in this test. Any tax credits
are considered a reduction to costs in this test. For fuel substitution programs, the costs also
include the increase in supply costs for the utility providing the fuel that is chosen as a result
of the program.
6
This test was previously called the All Ratepayers Test
19
How the Results Can be Expressed
The results of the Total Resource Cost Test can be expressed in several forms: as a net
present value, a benefit-cost ratio, or as a levelized cost. The net present value is the primary
unit of measurement for this test. Secondary means of expressing TRC test results are a
benefit-cost ratio and levelized costs. The Societal Test expressed in terms of net present
value, a benefit-cost ratio, or levelized costs is also considered a secondary means of
expressing results. Levelized costs as a unit of measurement are inapplicable for fuel
substitution programs, since these programs represent the net change of alternative fuels
which are measured in different physical units (e.g.,, kWh or therms). Levelized costs are
also not applicable for load building programs.
Net present value (NPVTRC) is the discounted value of the net benefits to this test over a
specified period of time. NPVTRC is a measure of the change in the total resource costs due
to the program. A net present value above zero indicates that the program is a less expensive
resource than the supply option upon which the marginal costs are based.
The benefit-cost ratio (BCRTRC) is the ratio of the discounted total benefits of the program
to the discounted total costs over some specified time period. It gives an indication of the rate
of return of this program to the utility and its ratepayers. A benefit-cost ratio above one
indicates that the program is beneficial to the utility and its ratepayers on a total resource cost
basis.
The levelized cost is a measure of the total costs of the program in a form that is sometimes
used to estimate costs of utility-owned supply additions. It presents the total costs of the
program to the utility and its ratepayers on a per kilowatt, per kilowatt hour, or per therm
basis levelized over the life of the program.
The Societal Test is structurally similar to the Total Resource Cost Test. It goes beyond the
TRC test in that it attempts to quantify the change in the total resource costs to society as a
whole rather than to only the service territory (the utility and its ratepayers). In taking
society's perspective, the Societal Test utilizes essentially the same input variables as the
TRC Test, but they are defined with a broader societal point of view. More specifically, the
Societal Test differs from the TRC Test in at least one of five ways. First, the Societal Test
may use higher marginal costs than the TRC test if a utility faces marginal costs that are
lower than other utilities in the state or than its out-of-state suppliers. Marginal costs used in
the Societal Test would reflect the cost to society of the more expensive alternative
resources. Second, tax credits are treated as a transfer payment in the Societal Test, and thus
are left out. Third, in the case of capital expenditures, interest payments are considered a
transfer payment since society actually expends the resources in the first year. Therefore,
capital costs enter the calculations in the year in which they occur. Fourth, a societal discount
rate should be used
7.
Finally, Marginal costs used in the Societal Test would also contain
externality costs of power generation not captured by the market system. An illustrative and
7 Many economists have pointed out that use of a market discount rate in social cost-benefit analysis
undervalues the interests of future generations. Yet if a market discount rate is not used, comparisons with
alternative investments are difficult to make
.
20
by no means exhaustive list of ‘externalities and their components’ is given below (Refer to
the Limitations section for elaboration.) These values are also referred to as ‘adders’
designed to capture or internalize such externalities. The list of potential adders would
include for example:
1. The benefit of avoided environmental damage: The CPUC policy specifies two ‘adders’
to internalize environmental externalities, one for electricity use and one for natural gas
use. Both are statewide average values. These adders are intended to help distinguish
between cost-effective and non cost-effective energy-efficiency programs. They apply to
an average supply mix and would not be useful in distinguishing among competing
supply options. The CPUC electricity environmental adder is intended to account for the
environmental damage from air pollutant emissions from power plants. The CPUC-
adopted adder is intended to cover the human and material damage from sulfur oxides
(SOX), nitrogen oxides (NOX), volatile organic compounds (VOC, sometimes called
reactive organic gases or ROG), particulate matter at or below 10 micron diameter
(PM10), and carbon. The adder for natural gas is intended to account for air pollutant
emissions from the direct combustion of the gas. In the CPUC policy guidance, the
adders are included in the tabulation of the benefits of energy efficiency programs. They
represent reduced environmental damage from displaced electricity generation and
avoided gas combustion. The environmental damage is the result of the net change in
pollutant emissions in the air basins, or regions, in which there is an impact. This change
is the result of direct changes in powerplant or natural gas combustion emission resulting
from the efficiency measures, and changes in emissions from other sources, that result
from those direct changes in emissions.
2. The benefit of avoided transmission and distribution costs – energy efficiency measures
that reduce the growth in peak demand would decrease the required rate of expansion to
the transmission and distribution network, eliminating costs of constructing and
maintaining new or upgraded lines.
3. The benefit of avoided generation costs – energy efficiency measures reduce
consumption and hence avoid the need for generation. This would include avoided
energy costs, capacity costs and T&D line
4. The benefit of increased system reliability: The reductions in demand and peak loads
from customers opting for self generation, provide reliability benefits to the distribution
system in the forms of:
a. Avoided costs of supply disruptions
b. Benefits to the economy of damage and control costs avoided by customers and
industries in the digital economy that need greater than 99.9 level of reliable
electricity service from the central grid
c. Marginally decreased System Operator’s costs to maintain a percentage reserve of
electricity supply above the instantaneous demand
d. Benefits to customers and the public of avoiding blackouts.
21
5. Non-energy benefits: Non-energy benefits might include a range of program-specific
benefits such as saved water in energy-efficient washing machines or self generation
units, reduced waste streams from an energy-efficient industrial process, etc.
6. Non-energy benefits for low income programs: The low income programs are social
programs which have a separate list of benefits included in what is known as the ‘low
income public purpose test’. This test and the sepcific benefits associated with this test
are outside the scope of this manual.
7. Benefits of fuel diversity include considerations of the risks of supply disruption, the
effects of price volatility, and the avoided costs of risk exposure and risk management.
Strengths of the Total Resource Cost Test
The primary strength of the Total Resource Cost (TRC) test is its scope. The test includes
total costs (participant plus program administrator) and also has the potential for capturing
total benefits (avoided supply costs plus, in the case of the societal test variation,
externalities). To the extent supply-side project evaluations also include total costs of
generation and/or transmission, the TRC test provides a useful basis for comparing demand-
and supply-side options.
Since this test treats incentives paid to participants and revenue shifts as transfer payments
(from all ratepayers to participants through increased revenue requirements), the test results
are unaffected by the uncertainties of projected average rates, thus reducing the uncertainty
of the test results. Average rates and assumptions associated with how other options are
financed (analogous to the issue of incentives for DSM programs) are also excluded from
most supply-side cost determinations, again making the TRC test useful for comparing
demand-side and supply-side options.
Weakness of the Total Resource Cost Test
The treatment of revenue shifts and incentive payments as transfer payments, identified
previously as a strength, can also be considered a weakness of the TRC test. While it is true
that most supply-side cost analyses do not include such financial issues, it can be argued that
DSM programs should include these effects since, in contrast to most supply options, DSM
programs do result in lost revenues.
In addition, the costs of the DSM "resource" in the TRC test are based on the total costs of
the program, including costs incurred by the participant. Supply-side resource options are
typically based only on the costs incurred by the power suppliers.
Finally, the TRC test cannot be applied meaningfully to load building programs, thereby
limiting the ability to use this test to compare the full range of demand-side management
options.
Formulas
22
The formulas for the net present value (NPV
TRC
)' the benefit-cost ratio (BCR
TRC
and
levelized costs are presented below:
NPVTRC = BTRC - CTRC
BCRTRC = BTRC /CTRC
LCTRC = LCRC / IMP
Where:
NPVTRC = Net present value of total costs of the resource
BCRTRC = Benefit-cost ratio of total costs of the resource
LCTRC = Levelized cost per unit of the total cost of the resource (cents per kWh for
conservation programs; dollars per kW for load management programs)
BTRC = Benefits of the program
CTRC = Costs of the program
LCRC = Total resource costs used for levelizing
IMP = Total discounted load impacts of the program
PCN = Net Participant Costs
The B
TRC
C
TRC
LCRC, and IMP terms are further defined as follows:
! !
= =
""
+
+
+
+
+
=
N
t
N
t
t
atat
t
tt
d
PACUAC
d
TCUAC
BTRC
1 1
11
)1()1(
!
=
"
+
++
=
N
t
t
ttt
d
UICPCNPRC
CTRC
1
1
)1(
!
=
"
+
"+
=
N
t
t
ttt
d
TCPCNPRC
LCRC
1
1
)1(
1
1 1
)1(
) ( )(
!
= =
+
"
#
$
%
&
'
=((=
) )
t
n
t
n
i
itit
d
periodpeakIwhereDNorENIMP
[All terms have been defined in previous chapters.]
The first summation in the BTRC equation should be used for conservation and load
management programs. For fuel substitution programs, both the first and second summations
should be used.
23
Chapter 5
Program Administrator Cost Test
Definition
The Program Administrator Cost Test measures the net costs of a demand-side management
program as a resource option based on the costs incurred by the program administrator
(including incentive costs) and excluding any net costs incurred by the participant. The
benefits are similar to the TRC benefits. Costs are defined more narrowly.
Benefits and Costs
The benefits for the Program Administrator Cost Test are the avoided supply costs of energy
and demand, the reduction in transmission, distribution, generation, and capacity valued at
marginal costs for the periods when there is a load reduction. The avoided supply costs
should be calculated using net program savings, savings net of changes in energy use that
would have happened in the absence of the program. For fuel substitution programs, benefits
include the avoided supply costs for the energy-using equipment not chosen by the program
participant only in the case of a combination utility where the utility provides both fuels.
The costs for the Program Administrator Cost Test are the program costs incurred by the
administrator, the incentives paid to the customers, and the increased supply costs for the
periods in which load is increased. Administrator program costs include initial and annual
costs, such as the cost of utility equipment, operation and maintenance, installation, program
administration, and customer dropout and removal of equipment (less salvage value). For
fuel substitution programs, costs include the increased supply costs for the energy-using
equipment chosen by the program participant only in the case of a combination utility, as
above.
In this test, revenue shifts are viewed as a transfer payment between participants and all
ratepayers. Though a shift in revenue affects rates, it does not affect revenue requirements,
which are defined as the difference between the net marginal energy and capacity costs
avoided and program costs. Thus, if NPVpa > 0 and NPVRIM < 0, the administrator’s
overall total costs will decrease, although rates may increase because the sales base over
which revenue requirements are spread has decreased.
How the Results Can be Expressed
The results of this test can be expressed either as a net present value, benefit-cost ratio, or
levelized costs. The net present value is the primary test, and the benefit-cost ratio and
levelized cost are the secondary tests.
24
Net present value (NPVpa) is the benefit of the program minus the administrator's costs,
discounted over some specified period of time. A net present value above zero indicates that
this demand-side program would decrease costs to the administrator and the utility.
The benefit-cost ratio (BCRpa) is the ratio of the total discounted benefits of a program to the
total discounted costs for a specified time period. A benefit-cost ratio above one indicates
that the program would benefit the combined administrator and utility's total cost situation.
The levelized cost is a measure of the costs of the program to the administrator in a form that
is sometimes used to estimate costs of utility-owned supply additions. It presents the costs of
the program to the administrator and the utility on per kilowatt, per kilowatt-hour, or per
therm basis levelized over the life of the program.
Strengths of the Program Administrator Cost Test
As with the Total Resource Cost test, the Program Administrator Cost test treats revenue
shifts as transfer payments, meaning that test results are not complicated by the uncertainties
associated with long-term rate projections and associated rate design assumptions. In contrast
to the Total Resource Cost test, the Program Administrator Test includes only the portion of
the participant's equipment costs that is paid for by the administrator in the form of an
incentive. Therefore, for purposes of comparison, costs in the Program Administrator Cost
Test are defined similarly to those supply-side projects which also do not include direct
customer costs.
Weaknesses of the Program Administrator Cost
Test
By defining device costs exclusively in terms of costs incurred by the administrator, the
Program Administrator Cost test results reflect only a portion of the full costs of the resource.
The Program Administrator Cost Test shares two limitations noted previously for the Total
Resource Cost test: (1) by treating revenue shifts as transfer payments, the rate impacts are
not captured, and (2) the test cannot be used to evaluate load building programs.
Formulas
The formulas for the net present value, the benefit-cost ratio and levelized cost are presented
below:
NPVpa = Bpa - Cpa
BCRpa = Bpa/Cpa
LCpa = LCpa/IMP
Where:
NPVpa Net present value of Program Administrator costs
BCRpa Benefit-cost ratio of Program Administrator costs
25
LCpa Levelized cost per unit of Program Administrator cost of the resource
Bpa Benefits of the program
Cpa Costs of the program
LCpc Total Program Administrator costs used for levelizing
!!
+
"
=
"
+
+
+
=
N
t
t
at
N
t
t
t
pa
d
UAC
d
UAC
B
1
1
1
1
)1()1(
!
=
"
+
++
=
N
t
t
ttt
pa
d
UICINCPRC
C
1
1
)1(
!
=
"
+
+
=
N
t
t
tt
d
INCPRC
LCpc
1
1
)1(
[All variables are defined in previous chapters.]
The first summation in the Bpa equation should be used for conservation and load
management programs. For fuel substitution programs, both the first and second summations
should be used.
26
Appendix A
Inputs to Equations and
Documentation
A comprehensive review of procedures and sources for developing inputs is beyond the
scope of this manual. It would also be inappropriate to attempt a complete standardization of
techniques and procedures for developing inputs for such parameters as load impacts,
marginal costs, or average rates. Nevertheless, a series of guidelines can help to establish
acceptable procedures and improve the chances of obtaining reasonable levels of consistent
and meaningful cost-effectiveness results. The following "rules" should be viewed as
appropriate guidelines for developing the primary inputs for the cost-effectiveness equations
contained in this manual:
1. In the past, Marginal costs for electricity were based on production cost model
simulations that clearly identify key assumptions and characteristics of the existing
generation system as well as the timing and nature of any generation additions and/or
power purchase agreements in the future. With a deregulated market for wholesale
electricity, marginal costs for electric generation energy should be based on forecast
market prices, which are derived from recent transactions in California energy markets.
Such transactions could include spot market purchases as well as longer term bilateral
contracts and the marginal costs should be estimated based on components for energy as
well as demand and/or capacity costs as is typical for these contracts.
2. In the case of submittals in conjunction with a utility rate proceeding, average rates used
in DSM program cost-effectiveness evaluations should be based on proposed rates.
Otherwise, average rates should be based on current rate schedules. Evaluations based on
alternative rate designs are encouraged.
3. Time-differentiated inputs for electric marginal energy and capacity costs, average
energy rates, and demand charges, and electric load impacts should be used for (a) load
management programs, (b) any conservation program that involves a financial incentive
to the customer, and (c) any Fuel Substitution or Load Building program. Costing periods
used should include, at a minimum, summer and winter, on-, and off-peak; further
disaggregation is encouraged.
4. When program participation includes customers with different rate schedules, the average
rate inputs should represent an average weighted by the estimated mix of participation or
impacts. For General Rate Case proceedings it is likely that each major rate class within
each program will be considered as program elements requiring separate cost-
effectiveness analyses for each measure and each rate class within each program.
27
5. Program administration cost estimates used in program cost-effectiveness analyses
should exclude costs associated with the measurement and evaluation of program impacts
unless the costs are a necessary component to administer the program.
6. For DSM programs or program elements that reduce electricity and natural gas
consumption, costs and benefits from both fuels should be included.
7. The development and treatment of load impact estimates should distinguish between
gross (i.e., impacts expected from the installation of a particular device, measure,
appliance) and net (impacts adjusted to account for what would have happened anyway,
and therefore not attributable to the program). Load impacts for the Participants test
should be based on gross, whereas for all other tests the use of net is appropriate. Gross
and net program impact considerations should be applied to all types of demand-side
management programs, although in some instances there may be no difference between
gross and net.
8. The use of sensitivity analysis, i.e. the calculation of cost-effectiveness test results using
alternative input assumptions, is encouraged, particularly for the following programs:
new programs, programs for which authorization to substantially change direction is
being sought (e.g.,, termination, significant expansion), major programs which show
marginal cost-effectiveness and/or particular sensitivity to highly uncertain input(s).
The use of many of these guidelines is illustrated with examples of program cost
effectiveness contained in Appendix B.
28
Appendix B
Summary of Equations and Glossary of
Symbols
Basic Equations
Participant Test
NPVP = BP - CP
NPVavp = (BP - CP) / P
BCRP = BP/CP
DPP = min j such that Bj > Cj
Ratepayer Impact Measure Test
LRIRIM = (CRIM - BRIM) / E
FRIRIM = (CRIM - BRIM) / E for t = 1
ARIRIMt = FRIRIM for t = 1
= (CRIMt- BRIMt )/Et for t=2,... ,N
NPVRIM = BRIM — CRIM
BCRRIM = BRIM /CRIM
Total Resource Cost Test
NPVTRC = BTRC - CTRC
BCRTRC = BTRC / CTRC
LCTRC = LCRC / IMP
Program Administrator Cost Test
NPVpa = Bpa - Cpa
BCRpa = Bpa / Cpa
LCpa = LCpa / IMP
29
Benefits and Costs
Participant Test
! !
= =
""
+
+
+
+
++
=
N
t
N
t
t
atat
t
ttt
d
PACAB
d
INCTCBR
Bp
1 1
11
)1()1(
!
=
"
+
+
N
t
t
tt
d
BIPC
Cp
1
1
)1(
Ratepayer Impact Measure Test
! !
= =
""
+
+
+
+
=
N
t
N
t
t
at
t
tt
RIM
d
UAC
d
RGUAC
B
1 1
11
)1()1(
!!
=
"
=
"
+
+
+
+++
=
N
t
t
at
N
t
t
tttt
RIM
d
RL
d
INCPRCRLUIC
C
1
1
1
1
)1()1(
!
=
"
+
=
N
t
t
t
d
E
E
1
1
)1(
Total Resource Cost Test
! !
= =
""
+
+
+
+
+
=
N
t
N
t
t
atat
t
tt
TRC
d
PACUAC
d
TCUAC
B
1 1
11
)1()1(
!
=
"
+
++
=
N
t
t
ttt
TRC
d
UICPCNPRC
C
1
1
)1(
!
=
"
+
"+
=
N
t
t
ttt
TRC
d
TCPCNPRC
L
1
1
)1(
30
1
1 1
)1(
) ( )(
!
= =
+
"
#
$
%
&
'
=((=
) )
t
n
t
n
i
itit
d
periodpeakIwhereDNorENIMP
Program Administrator Cost Test
! !
= =
""
+
+
+
=
N
t
N
t
t
at
t
t
pa
d
UAC
d
UAC
B
1 1
11
)1(
)1(
!
=
"
+
++
=
N
t
t
ttt
pa
d
UICINCPRC
C
1
1
)1(
!
=
"
+
+
=
N
t
t
tt
d
INCPRC
LCPA
1
1
)1(
Glossary of Symbols
Abat = Avoided bill reductions on bill from alternate fuel in year t
AC:Dit = Rate charged for demand in costing period i in year t
AC:Eit = Rate charged for energy in costing period i in year t
ARIRIM = Stream of cumulative annual revenue impacts of the program per unit of
energy, demand, or per customer. Note that the terms in the ARI formula
are not discounted, thus they are the nominal cumulative revenue impacts.
Discounted cumulative revenue impacts may be calculated and submitted if
they are indicated as such. Note also that the sum of the discounted
stream of cumulative revenue impacts does not equal the LRIRIM*
BCRp = Benefit-cost ratio to participants
BCRRIM = Benefit-cost ratio for rate levels
BCRTRC = Benefit-cost ratio of total costs of the resource
BCRpa = Benefit-cost ratio of program administrator and utility costs
BIt = Bill increases in year t
Bj = Cumulative benefits to participants in year j
Bp = Benefit to participants
BRIM = Benefits to rate levels or customer bills
BRt = Bill reductions in year t
BTRC = Benefits of the program
Bpa = Benefits of the program
Cj = Cumulative costs to participants in year i
31
Cp = Costs to participants
CRIM = Costs to rate levels or customer bills
CTRC = Costs of the program
Cpa = Costs of the program
D = discount rate
ΔDgit = Reduction in gross billing demand in costing period i in year t
ΔDnit = Reduction in net demand in costing period i in year t
DPp = Discounted payback in years
E = Discounted stream of system energy sales-(kWh or therms) or demand
sales (kW) or first-year customers
ΔEgit = Reduction in gross energy use in costing period i in year t
ΔEnit = Reduction in net energy use in costing period i in year t
Et = System sales in kWh, kW or therms in year t or first year customers
FRIRIM = First-year revenue impact of the program per unit of energy, demand, or
per customer.
IMP = Total discounted load impacts of the program
INCt = Incentives paid to the participant by the sponsoring utility in year t First
year in which cumulative benefits are > cumulative costs.
Kit = 1 when ΔEGit or ΔDGit is positive (a reduction) in costing period i in year
t, and zero otherwise
LCRC = Total resource costs used for levelizing
LCTRC = Levelized cost per unit of the total cost of the resource
LCPA = Total Program Administrator costs used for levelizing
Lcpa = Levelized cost per unit of program administrator cost of the resource
LRIRIM = Lifecycle revenue impact of the program per unit of energy (kWh or therm)
or demand (kW)-the one-time change in rates-or per customer-the change
in customer bills over the life of the program.
MC:Dit = Marginal cost of demand in costing period i in year t
MC:Eit = Marginal cost of energy in costing period i in year t
NPVavp = Net present value to the average participant
NPVP = Net present value to all participants
NPVRIM = Net present value levels
NPVTRC = Net present value of total costs of the resource
NPVpa = Net present value of program administrator costs
OBIt = Other bill increases (i.e., customer charges, standby rates)
OBRt = Other bill reductions or avoided bill payments (e.g., customer charges,
standby rates).
P = Number of program participants
PACat = Participant avoided costs in year t for alternate fuel devices
32
PCt = Participant costs in year t to include:
Initial capital costs, including sales tax
Ongoing operation and maintenance costs
Removal costs, less salvage value
Value of the customer's time in arranging for installation, if significant
PRCt = Program Administrator program costs in year t
PCN = Net Participant Costs
RGt = Revenue gain from increased sales in year t
RLat = Revenue loss from avoided bill payments for alternate fuel in year t
(i.e., device not chosen in a fuel substitution program)
RLt = Revenue loss from reduced sales in year t
TCt = Tax credits in year t
UACat = Utility avoided supply costs for the alternate fuel in year t
UACt = Utility avoided supply costs in year t
PAt = Program Administrator costs in year t
UICt = Utility increased supply costs in year t
33
Appendix C.
Derivation of Rim Lifecycle Revenue
Impact Formula
Most of the formulas in the manual are either self-explanatory or are explained in the text.
This appendix provides additional explanation for a few specific areas where the algebra was
considered to be too cumbersome to include in the text.
Rate Impact Measure
The Ratepayer Impact Measure lifecycle revenue impact test (LRIRIM) is assumed to be the
one-time increase or decrease in rates that will re-equate the present valued stream of
revenues and stream of revenue requirements over the life of the program.
Rates are designed to equate long-term revenues with long-term costs or revenue
requirements. The implementation of a demand-side program can disrupt this equality by
changing one of the assumptions upon which it is based: the sales forecast. Demand-side
programs by definition change sales. This expected difference between the long-term
revenues and revenue requirements is calculated in the NPVRIM The amount which present
valued revenues are below present valued revenue requirements equals NPVRIM
The LRIRIM is the change in rates that creates a change in the revenue stream that, when
present valued, equals the NPVRIM* If the utility raises (or lowers) its rates in the base year
by the amount of the LRIRIM' revenues over the term of the program will again equal
revenue requirements. (The other assumed changes in rates, implied in the escalation of the
rate values, are considered to remain in effect.)
Thus, the formula for the LRIRIM is derived from the following equality where the present
value change in revenues due to the rate increase or decrease is set equal to the NPVRIM or
the revenue change caused by the program.
!
=
"
+
#
="
N
t
t
tRIM
RIM
d
ELRI
NPV
1
1
)1(
Since the LRI
RIM
term does not have a time subscript, it can be removed from the summation,
and the formula is then:
!
=
"
+
#="
N
t
t
t
RIMRIM
d
E
LRINPV
1
1
)1(
34
Rearranging terms, we then get:
!
=
"
+
"=
N
t
t
t
RIMRIM
d
E
NPVLRI
1
1
)1(
Thus,
!
=
"
+
=
N
t
t
t
d
E
E
1
1
)1(