Achievable Savings 

A Retrospective Look at the Northwest Power and Conserv

Conservation Planning Assumptions 

Council Document 2007-7 May 2007 

Executive Summary 

The Northwest Power Act of 1980, the federal law that authorized the states of Idaho, Montana, 

Oregon, and Washington to form the Northwest Power and Conservation Council, directs the 

Council and the Bonneville Power Administration to treat energy conservation -- improved 

efficiency of electricity use -- as a resource equal to electricity generation when planning to meet 

future demand for power. The Act requires Bonneville to acquire all cost-effective conservation 

first before acquiring new power from generating resources. 

The Act also directs the Council to prepare, and to review, at least every five years, a regional 

electric power plan to ensure an adequate, efficient, economical, and reliable electricity supply in 

the Pacific Northwest. The administrator of Bonneville is required by the Act to make resource 

acquisition decisions that are consistent with the Council’s power plan. Consistent with the 

Power Act, energy conservation is the highest-priority resource in the Council’s power plan. 

The Council evaluates the conservation, along with generating resources, to determine a regional 

plan for electric resource development that is consistent with the goals of the Act. To assist the 

Council in determining the cost-effectiveness of generating and conservation resources in the 

power plan, the Act establishes three criteria. A cost-effective resource or measure is one that is 

forecast by the Council to be 1) reliable, 2) available when it is needed, and 3) no more 

expensive than the least-cost alternative resource. 

From this instruction, the Council developed a methodology to identify conservation that is 

reliable, available and cost-effective. The methodology identifies the technically feasible 

potential conservation measures in the region, the cost of the measures and any timing 

constraints to their implementation. Using this methodology, the Council identifies the 

maximum rate of annual deployment of conservation measures. The methodology also produces 

an estimate of the maximum achievable potential of the measures over the 20-year planning 

horizon required by the Act. The estimates of reliable and available conservation represent what 

conservation is achievable. The estimates of what is achievable, along with estimates of the cost 

of the conservation, are then used in the Council’s planning analysis to develop five-year targets 

for the development of cost-effective conservation and other resources that meet the goals of the 

Act. 

The Council divides conservation measures into two categories with respect to availability. One 

category includes measures that can be acquired at any time, such as installing low-flow shower 

heads. These are called non-lost opportunity measures, or retrofit measures. The other category 

includes measures that can only be acquired cost effectively at a specific time, such as extra wall 

ation Council’s 
insulation in buildings that are under construction. These are called lost-opportunity measures. 

If they are not implemented at a specific time, the opportunity to implement them is lost. In its 

planning, the Council assumes that the upper limit of achievable conservation acquisition (this is 

called “penetration”) in the region is 85 percent of the technically achievable potential. But, with 

respect to time, the availability of these two types of conservation differs. For retrofit 

conservation, the Council assumes near-term annual acquisition rates that are similar to the high 

range of historic rates. However, because lost-opportunity measures have limited windows of 

availability, the Council assumes a gradual increase to the upper limit of 85 percent penetration 

for lost-opportunity measures. As a result, only about 65 percent of lost-opportunity measures 

are achievable over the 20-year planning period on average. 

There is ample empirical evidence to support retaining these long-term planning assumptions, as 

both are supported by actual experience during the last 20 years. This paper reviews 

assumptions about the amount and timing of achievable conservation from the Council’s 1983 

power plan and compares them to what happened in the years since. For example, before the end 

of 1992 -- not quite 10 years after the Council issued its first power plan -- Washington and 

Oregon, the two most populous states in the region, already had met 100 percent of the energysavings goals for new homes in the first power plan. By 2002 all four Northwest states had met 

the goals of the plan for residential conservation in new homes. Similar examples, where 

experience exceeds planning assumptions, are presented for new manufactured homes, 

appliances, lighting in new commercial buildings, new motors and other measures where data are 

available. 

Further, the Council’s assumed near-term achievable acquisition rates for non-lost-opportunity 

measures are well-supported and may be conservative when compared to what has occurred in 

practice. In the last five years the region has reduced demand for electricity through 

conservation measures at a rate of about 130-150 average megawatts per year. Retrofits, or nonlost-opportunity measures, comprise 110-120 average megawatts per year of the total. If that 

pace is maintained, it will take 12 to 14 years, not 20, to reach the 85-percent penetration rate for 

the 1,500 average megawatts of cost-effective, non-lost opportunity conservation identified in 

the Council’s Fifth Power Plan (the Council issued this plan in December 2004). 

Finally, assumptions about near-term conservation acquisition rates are more important than 

looking ahead 20 years. The 20-year timeframe stipulated in the Act for the Council’s power 

and conservation planning was more relevant in 1980 when new generating plants took up to 15 

years to site, license, and build. Today, new generating facilities and transmission system

expansions can be brought on line in three to five years. Therefore, it is more relevant today to 

predict reliably the pace at which conservation programs can be “ramped up” and maintained 

over the near-term. 

Background 

In 2007 there is a resurgent interest in the Council’s approach to integrated resource planning in 

general, and its methodology for incorporating conservation in its Northwest power plans in 

particular. There are several reasons. For the region’s public utilities, Bonneville’s pending 

proposal to serve the load growth of its preference customers at “market-based” rates rather than 

Council document 2007-7 2
embedded costs encourages them to consider their resource choices more systematically. In 

Washington State, the enactment of HB1010 and the passage of Initiative 937 (I-937) created 

additional impetus for the state’s larger utilities, public and investor-owned. HB1010 requires 

utilities to prepare resource plans to demonstrate that they have adequate resources to meet their 

load-serving obligations.1

 I-937 requires utilities to develop all conservation that is costeffective, reliable, and feasible using methodologies consistent with those used by the Council.

2

 

Because I-937 specifically references the Council’s methodology there is heightened interest in 

understanding how the Council assesses achievable conservation potential. The purpose of this 

paper is to provide an overview of the Council’s methodology and an assessment of whether its 

current planning assumptions regarding “achievable” savings are supported by evidence. 

The Council’s Conservation Planning Methodology 

The Northwest Power Act establishes three criteria for resources included in the Council’s power 

plans: resources must be 1) reliable; 2) available within the time they are needed, and 3) 

available at an estimated incremental system cost no greater than that of the least-cost similarly 

reliable and available alternative.3 Beginning with its first power plan in 1983, the Council 

interpreted these requirements to mean that conservation resources included in the plans must be: 

• technically feasible (reliable) 

• economically feasible (lower cost) 

• achievable (available) 

The first step in the Council’s methodology is to identify all of the technically feasible potential 

conservation savings in the region. This involves the review of a wide array of commercially 

available technologies and practices for which there is documented evidence of electricity 

savings. This step also involves determining the number of potential applications in the region 

for each of these technologies or practices. For example, electricity savings from higher 

efficiency water heaters are only “technically feasible” in homes that have, or are forecast to 

have, electric water heaters. Similarly, increasing attic insulation in homes can only produce 

electricity savings in electrically heated homes that do not already have fully insulated attics. 

The second step in the Council’s process is to determine the total resource cost of the energy 

savings from all of those measures that are technically feasible. This process requires the 

comparison of the all of the costs of a measure with all of its benefits, regardless of who pays 

those costs or receives the benefits. In the case of a more efficient clothes washer, cost includes 

the difference (if any) in retail price between the Energy Star model and the “standard

efficiency” model, plus any utility program administrative and marketing cost. On the other side

of the equation, benefits include the energy (kilowatt-hour) and capacity (kilowatt) savings, 

 

1

http://www.cted.wa.gov/DesktopModules/CTEDPublications/CTEDPublicationsView.aspx?tabID=0&ItemID=403

9&MId=863&wversion=Staging 2 Energy Independence Act. RCW 19.285.040(1)(a) (http://apps.leg.wa.gov/RCW/default.aspx?cite=19.285.040) 3

 See Section 839a(4)(A)(i) and (ii) of the Northwest Power Planning and Conservation Act. 

(http://www.nwcouncil.org/library/poweract/3_definitions.htm or 

http://www.nwcouncil.org/LIBRARY/poweract/poweract.pdf) 

Council document 2007-7 3
water and wastewater treatment savings, and savings on detergent costs.4

 While not all of these 

costs and benefits are either paid by or accrue to the region’s power system, they are included in 

the evaluation because ultimately they are paid by or benefit the region’s consumers. 

Once the net cost (present value of all cost minus the present value of all benefits) of each of the 

conservation technologies or practices is determined, the technologies are ranked by cost in two 

“supply curves” that depict the amount of conservation resource potential available in the region. 

One “supply curve” represents all of the retrofit or “non-lost opportunity” resources. The other 

represents all of the “lost-opportunity” conservation resources.5

 The Council divides 

conservation resources into these two categories because their patterns of potential deployment 

are different. Non-lost opportunity conservation resources can be captured at any time. Lostopportunity resources are only available during specific periods. For example, savings from

improved wall insulation in new buildings are only available when the building is constructed. 

Savings from most appliances are available only as appliance stock turns over. If the savings 

from these lost-opportunity resources are not acquired within this limited window of opportunity, 

they are treated as lost and no longer available to be deployed. 

The third step in the Council’s process is to establish any timing constraints on the availability of

the conservation contained in these supply curves. These constraints are needed in the Council’s 

portfolio modeling process. The portfolio model selects the quantity and timing of all resource 

development. Because significant quantities of conservation are available at costs below most 

forecasts of future market prices, the portfolio model will “dispatch” all of the low-cost 

conservation immediately unless the pace of conservation deployment is constrained. 

Thus the Council establishes two types of constraints on the amount of available conservation. 

The first is on the rate of annual deployment. This constraint represents the upper limit of annual 

conservation resource development. In the Council’s Fifth Northwest Power Plan, non-lost 

opportunity resource development was limited to 120 average megawatts per year. On the other 

hand, lost-opportunity resources are more difficult to capture because of the limited window of 

opportunity. So lost-opportunity deployment was based on penetration rates of 15 percent 

achievable in 2005 and increasing to 85 percent achievable over 12 years. 

The second constraint is the maximum achievable potential over the 20-year period covered by 

the Council’s power plans. In the case of non-lost opportunity resources, the Council set an 

upper limit of 85 percent of the technically feasible and cost-effective savings. Because lostopportunity resources are phased in to an upper limit of 85 percent market penetration over 12 

years, the cumulative 20-year penetration of lost-opportunity conservation equates to 65 percent 

of the technically feasible and cost-effective savings. 

 

Figures 1 and 2 show the conservation supply curves for lost-opportunity and non-lostopportunity resources used in the Council’s Fifth Power Plan. 

 

4

 More energy efficiency clothes washers use less water and hence require less detergent. 5

 Lost-opportunity resources are those that can only be technically or economically captured during a limited

window of opportunity, such as when a building is built or industrial process is upgraded. 

Council document 2007-7 4
Figure 1 - Annual Lost-Opportunity Achievable Potential Supply Curve

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$0 $10 $20 $30 $40 $50 $60 $70 $80 $90 $100 $110 $120

Levelized Cost (2004$/MWH)

Achievable Potential (a

M

W)

2005 (aMW/yr)

2007 (aMW/yr)

2009 (aMW/yr)

20011 (aMW/yr)

20013 (aMW/yr)

2015 - 2024 (aMW/yr)

As shown in Figure 1, the Council’s planning methodology anticipates that the share of lostopportunity resources that is achievable at a given cost increases over time. For example, at up 

to a levelized cost of $60 per megawatt-hour, only 10 average megawatts of the lost-opportunity 

resources are considered achievable in 2005. However, for the years 2015 and beyond, just over 

60 average megawatts of savings are available each year at this same levelized cost. 

Figure 2 shows the total achievable potential of non-lost opportunity resources. 

Figure 2 - Non-Lost Opporunity Achievable Potential (aMW)

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Levelized Cost (2004$/MWH)

Achievable Potential (aM

W)

Figure 3 shows the expected value and annual deployment rate of those resources from 2005 

through 2024 as well as the annual deployment rate of lost-opportunity resources over this same

time period. As can be seen from Figure 3, the maximum amount of non-lost opportunity 

resource development remains constant at 120 average megawatts per year until 2015 and then 

declines significantly. This is a result of the fact that by 2015 all of the lower cost (<$50 /MWH) 

non-lost opportunity resources have been acquired and only in futures where prices are higher 

Council document 2007-7 5
are the more costly conservation resources developed. A total of about 1,600 average megawatts 

of non-lost opportunity conservation is deployed over 20 years. But most of it, about 1,400 

average megawatts, is deployed in the first 12 years. Figure 3 also shows that the amount of lostopportunity resources developed annually increases over time until it reaches a “steady state” of 

around 70 average megawatts per year. That level represents 85 percent of the annual technical 

and cost-effective lost-opportunity potential. However, in the first 10 years, the Council assumes 

a gradual ramp up of achievable lost-opportunity conservation. In fact, over the first 10 years, 

the achievable penetration rate is only about 50 percent on average for lost-opportunity 

measures. 

Figure 3 - Annual Level of Conservation Acquisitions in Council's 5th Plan

 (Mean level of development across 750 futures)

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2005 2007 2009 2011 2013 2015 2017 2019 2021 2023 2025

Year

Annual Acquisitions (aM

W)

Non Lost Opportunity Resources

Lost Opportubnity

The first two filters in the Council’s screening process, technical feasibility and cost, involve less

“subjective” assessments than does the application of the “achievability” filter. Therefore, it is 

important to understand the basis of the Council’s constraint on achievable conservation. The 

Council established the 85-percent upper limit in its first power plan in 1983 and has used this 

limit in all subsequent plans. The limit is based on the actual achievements in the Hood River 

Conservation Project sponsored by the Bonneville Power Administration and operated by 

PacifiCorp (then called Pacific Power and Light Company). The Hood River Conservation 

Project made weatherization measures available to all Hood River County residents with electric 

heat at no cost over a period of two years. In this project 85 percent of technically feasible 

weatherization measures in the electrically heated residences were installed within a period of 

two years.6

 

While the Hood River project set one mark for how much conservation is achievable, the 

Council also adopted the 85-percent value because, in its judgment, the region had access to 

 

6

 “Cooperation and Community Conservation,” report on Hood River Conservation Project, 1987, by Oak Ridge 

National Laboratory for Bonneville Power Administration and Pacific Power & Light. 

Council document 2007-7 6
multiple “tools” that could be used to achieve this goal. First, the region had 20 years to achieve 

the 85 percent goal.7

 Second, Bonneville and utilities can offer significant financial incentives to 

encourage consumers to adopt energy-efficient technologies and practices called for in the 

Council’s power plans. Indeed, by definition, Bonneville and utilities can offer to pay up to the 

full incremental cost of all cost-effective energy-efficient technologies or practices to encourage 

consumers to install them. In the Council’s judgment, it seems realistic to assume that the 

combined ability to offer the more energy-efficient technologies and practices at no additional 

cost to consumers over a 20-year period would result in an 85-percent market penetration of 

those measures. Finally, in addition to offering financial incentives, that Bonneville and utilities 

had the ability to work at both the state and federal level to enact standards and improve codes 

that would require the use of more energy-efficient technologies and practices by law. 

In addition to the Hood River project, the Council is aware of only one other empirical test of 

comparable scale that addresses the question of how much of the technically and economically 

feasible conservation potential in the region is actually “achievable.” 

1983 Power Plan Achievable Conservation Potential: Goals and Actual Achievements 

The 1983 Plan included a range of future load growth forecasts and resource scenarios to meet 

them. In the “high forecast” case, the 1983 Plan targeted over 4,900 average-megawatts of 

conservation savings by 2002. In the “low forecast” case, the plan’s target was less than 700 

average-megawatts. According the Council’s recent analysis, by the end of 2002 the region had 

acquired just over 2,300 average-megawatts of savings. It is not possible to directly compare 

this value with the “achievable potential” in the 1983 Plan, for two reasons. First, the “actual” 

load growth experienced between 1983 and 2002 does not correspond with any of the 1983 

Plan’s four forecasts. Thus, the amount of potentially achievable “lost-opportunity” resources 

that could have been developed does not match the 1983 Plan’s resource assessment. Second, 

Bonneville and utility conservation acquisition programs did not operate in a sustained manner 

over this period. In fact, during the mid 1980s and late 1990s Bonneville and utility conservation 

programs were significantly curtailed. Therefore, any comparison between the 1983 Plan’s 

conservation goals, which were forecast to be achieved over 20 years, and the actual results 

would be misleading. 

However, it is possible to compare many of the 1983 Plan’s specific estimates of achievable 

potential with what actually occurred. In particular, the 1983 Plan contained a detailed forecast 

of achievable conservation potential for residential and commercial buildings, appliances, and 

equipment.8

 

7

 The Council also viewed its 85-percent goal as having limited risk because its power plans are updated every five 

years. If progress toward the goal is slow, then adjustments to the timing of the development of other resources can 

be made. 8

 1983 Northwest Power and Conservation and Electric Power Plan, Volume II, Appendix K. Northwest Power 

Planning Council. Portland, OR. 

Council document 2007-7 7
Residential Sector 

The 1983 Plan estimated achievable conservation potential for new and existing space heating, 

appliances, lighting, and water heating. With respect to new space heating, the Plan called upon 

the region to adopt energy codes that were equivalent to the Council’s Model Conservation 

Standards (MCS). The MCS represented a 40-percent savings over the construction practices 

and codes of 1983. Table 1 below compares the “prescriptive requirements” of 1983 Model 

Conservation Standards with the 1992 energy code requirements in Oregon and Washington. 

The table shows that by 1992 energy code requirements in Oregon and Washington were nearly 

identical to the Council’s 1983 MCS. These energy code requirements were adopted in Oregon 

in 1992 and in Washington in 1991, less than 10 years after the Council established the MCS. 

. 

Table 1 

1983 Plan Model Conservation Standards 

versus

 1992 Oregon and Washington Energy Code Requirements 

Component MCS - 

Zone 1 

MCS - 

Zone 2 

MCS - 

Zone 3 

WA 

Code - 

Zone 1 

WA 

Code - 

Zone 2 

OR Code 

All Zones 

Ceiling/Attic R-38 R-38 R-38 R-38 R-38 R-38

Wall R-19 R-25 R-25 R-19 R-19 R-21

Floor R-30 R-30 R-30 R-30 R-30 R-25

Window U-0.37 U-0.37 U-0.37 U-0.40 U-0.35 U-0.40

Door R-5 R-5 R-5 R-5 R-5 R-5 

Slab R-10 R-12 R-15 R-10 R-10 R-15

The Council’s 1983 Plan anticipated that it would take until 2002 for the region to achieve 85 

percent of MCS savings potential. Table 2 shows the estimated regional (all four states) average 

electric space heating requirements, normalized to kilowatt-hours per square foot, for new homes 

built under various “vintages” of energy codes. This table shows that by 1992 the entire region 

had already achieved that goal (85 percent of 40 percent is 34 percent) and that by 2006 the 

region had slightly exceeded the Council’s original MCS efficiency levels.

Table 2 

Regional Average Annual Space Heating Use of New Single Family Homes 

Constructed Between 1983 and 2006 

Vintage Annual Use 

(kWh/SF/yr.)

Percent 

of 1983 

Use 

Improvement 

over 1983 

1983 6.3 100% 0% 

1986 5.5 88% 12% 

1989 5.4 86% 14% 

1992 4.0 64% 36% 

Current Practice - 2006 3.7 59% 41% 

Council document 2007-7 8
Further evidence of the pace of efficiency improvement in new homes is shown in Table 3. This

table shows the average heat loss rate derived from field audits of a random sample of homes 

across the region collected as part of a regional heat pump performance evaluation. As can be 

seen from Table 3, the average heat loss rate of the homes in the 2001 vintage is 35 percent 

lower than for the homes built in 1983, clearly reflecting the improvements in energy codes and 

construction practices across the region. For site-built homes, regulation via state energy codes 

was critical to achieving high rates of market penetration. Furthermore, improvements in the 

state’s energy codes and federal standards remain an excellent tool for capturing further energy 

efficiency savings. 

Table 3 - Average Heat Loss Rate for New Single Family Homes 

Built Between 1980 - 2003

Vintage Heat Loss Rate 

(BTU/hr/sq.ft. floor 

area 

Improvement over 

1983 Code/Practice 

1980-1984 0.260 0% 

1985-1988 0.247 5% 

1989-1991 0.194 25% 

1992-1999 0.182 30% 

2000-2003 0.170 35% 

Manufactured housing provides an example of similar achievable penetration rates, but without 

reliance on the regulatory approach used to achieve the savings from site built housing. The 

1983 Plan assumed that the MCS did not apply to new manufactured homes because federal law 

pre-empted the state regulation of energy efficiency aspects of these homes. Consequently, no 

savings from this market segment was included in that Plan’s forecast of achievable potential. 

However, beginning in the mid-1980s the region’s manufactured housing industry began 

working with Bonneville and the state energy offices to develop options for improving the 

efficiency of these homes -- over 80 percent of which use electric space heating. Early in 1992, 

just as the new “MCS equivalent” energy codes for site-built homes were adopted, all of the 

region’s manufactured home builders agreed to build all of their new electrically heated homes to 

MCS levels. From 1992 through mid-1995, all new electrically heated manufactured homes 

generated savings that were not envisioned as “achievable” in the 1983 Plan. 

Table 4 shows the annual penetration rate achieved for “MCS-level” efficiency manufactured 

homes between 1988 and 2005. Two periods shown in this table are noteworthy. The first 

period of interest is the period between 1988 and 1994, which indicates the rapid increase in 

market penetration of these more efficient homes. This period demonstrates that with a 

concerted effort and program design, the region achieved almost 90 percent of the technically 

feasible and cost-effective potential of this lost-opportunity resource without regulation. It is 

also worthy of note that this far exceeds the pace of market share increase assumed over 12 years 

as the upper limit of achievability for lost-opportunity resources used in the Council’s Fifth 

Power Plan. 

Council document 2007-7 9
Table 4 - Model Conservation Standard Equivalent Manufactured Home Shipments 

and Market Share 1988 - 2006 

Year SGC/NC 

Shipments 

Total Shipments SGC/NC 

Market Share

1988 29 9,049 0% 

1989 135 9,967 1% 

1990 684 11,875 6% 

1991 2,081 11,815 18% 

1992 11,000 13,784 80% 

1993 15,094 17,535 86% 

1994 18,356 20,512 89% 

1995 15,710 19,641 80% 

1996 11,503 17,125 67% 

1997 9,231 17,301 53% 

1998 7,677 17,996 43% 

1999 5,366 14,620 37% 

2000 3,475 9,564 36% 

2001 3,828 7,437 51% 

2002 4,887 8,029 61% 

2003 4,669 7,384 63% 

2004 4,654 7,601 61% 

2005 4,754 7,834 61% 

The second period of note is between 1996 and 2002 when the region’s manufacturers first 

abandoned the production of energy-efficient homes and then returned to building these homes 

after discovering that the market did not want the less-efficient products they were trying to sell. 

While not specifically germane to the issue of “achievable potential,” this market trend clearly 

demonstrates that even without regulation, higher levels of efficiency for manufactured housing 

sold in this region has become the market norm. 

The 1983 Plan anticipated that by 2002 the region would have weatherized approximately 1.27 

million existing electrically heated homes. Unfortunately, data collection processes that permit a 

direct comparison with this forecast were not in place during the period prior to 1991. However, 

current utility residential weatherization programs continue to produce savings, so it is clear that 

not all homes in the region have been fully weatherized. It is also clear that the pace of 

residential weatherization has slowed considerably since the early 1980’s. For example, less 

than 7 average megawatts of residential weatherization savings were reported by the utilities 

participating in Bonneville’s Conservation and Renewable Resources Rate Discount Program for 

the fiscal years 2001 through 2006. In comparison, Bonneville reported over 50 average 

megawatts of residential savings from 1991 through 1996, primarily from residential 

weatherization measures. While this may or may not be an indication of whether the 85 percent 

market saturation rate of technically and economically feasible measures has been reached, it 

does appear that this market is reaching saturation. 

Council document 2007-7 10
Residential appliances offer another window into the viability of achievable conservation 

assumptions. Data on the energy savings from major residential appliances, water heating and 

lighting are available. The 1983 Plan assumed that by 2003 average residential water heating use 

could be reduced by about 12 percent from roughly 5,150 kilowatt-hours per home per year to 

4,530 kilowatt-hours per home per year. Three measures were identified to achieve this: 1) 

increased tank insulation; 2) lower-flow showerheads, and 3) lower the water tank temperature 

(from 140 degrees Fahrenheit to 130). As of 1991 the minimum federal standard for electric 

water heaters required that the average 50 gallon tank use less than 4,220 kilowatt-hours per 

year. This surpasses the Council’s forecast of achievable potential with just one of these three 

measures (tank insulation) in less than ten years. In 1994 federal standards mandated that 

showerheads not exceed flow rates of 2.5 gallons per minute and that temperature on all water 

heaters be set at the factory at 120 degrees Fahrenheit for safety reasons. The 1994 federal 

standard was below the 2.75 gallons per minute showerhead flow rate assumed to be achievable 

in the 1983 Plan. In combination with the mandated lower water temperature, the achievable 

energy savings from residential water heating were nearly 50 percent higher than anticipated in 

the 1983 Plan.9

 Furthermore, the Council’s 20-year target for improving water heating 

efficiency by 12 percent was exceeded in just ten years. 

In 1983 the Council forecast that the achievable potential savings between the average electricity 

consumption of a new refrigerator and the most efficient model on the market would result in a 

savings of 515 kilowatt-hours per year. For freezers, the savings potential was just 35 kilowatthours per year. The Council did not break out its specific assumptions for clothes washers and 

dishwashers, but it did indicate that between these two appliances it anticipated that an annual 

savings of 340 kilowatt-hours should be achievable by 2002. Figures 4 and 5 show the “salesweighted average” energy use of each of these appliances by year of purchase. As can be seen 

from these figures, the actual efficiency improvements for both refrigerators and freezers not 

only exceeded the forecast of achievable potential in the 1983 Plan, but they were achieved far 

early than forecast. Figures 4 and 5 are based on data reported by the Association of Home

Appliance Manufacturers (AHAM), the appliance manufacturing industry trade association. 

 

9

 In 2004, the federal minimum standard for a typical 50 gallon electric water heater resulted in electricity use of 

4,060 kilowatt-hours per year.

Council document 2007-7 11
Figure 4 - Average Energy Use of New Refrigerators

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1983198419851986198719881989199019911992199319941995199619971998199920002001200220032004

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Efficiency by 2002

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Efficiency

1983 Plan Base Use

Figure 5 - Average Energy Use of New Freezers

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1983 Plan Achievable 

Efficiency by 2002

Actual 2002 Efficiency

1983 Plan Base Use

Figures 6 and 7 show AHAM’s sales-weighted average energy use for dishwashers and clothes 

washers for each year between 1983 and 2004. Also shown are the 1983 Plan’s implied 

achievable potential savings for new dishwashers and clothes washers. As was the case with 

refrigerators and freezers, it appears that the 1983 Plan’s forecast of achievable savings for 

dishwashers proved to be overly conservative. On the other hand, the Council’s assessment of 

Council document 2007-7 12
achievable efficiency improvements in clothes washer efficiency roughly correspond to the 

actual improvement in this appliance’s energy use in 2002. However, it should be noted that by 

2004, just two years later, the sales weighted average energy use of new clothes washers was 

almost half that anticipated in 1983 for machines sold in 2002. 

Figure 6 - Average Energy Use of New Dishwashers

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1983198419851986198719881989199019911992199319941995199619971998199920002001200220032004

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Efficiency by 2002

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1983 Plan Base Use

Figure 7 - Average Energy Use of New Clothes Washers

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Efficiency by 2002

Actual 2002 Efficiency

1983 Plan Base Use

Council document 2007-7 13
The 1983 Plan also anticipated efficiency improvements in residential lighting. That plan 

assumed that by 2002 the average home would use approximately 170 kilowatt-hours per year 

less for lighting than it did in 1983. While the 1983 Plan assumed that linear fluorescent lighting 

technologies could be employed to achieve these savings, it appears that compact fluorescent 

lamps (CFLs) are actually being used to achieve most of these savings. Based on surveys done 

for the Northwest Energy Efficiency Alliance, it appears that on average homes in the region had 

two to three CFLs installed by the end of 200210. Based on the Council’s current savings 

assumptions, this would translate into between 70 and 105 kilowatt-hours per home per year of 

savings. These savings are approximately half those anticipated as being achievable in 1983. 

Commercial Sector 

The data we have for new commercial buildings tell a similar story; today’s energy codes far 

exceed the achievable penetration rates identified by the Council twenty years ago. In the 1983 

Plan (as is the case in the Fifth Power Plan) the largest portion of the commercial sector’s 

achievable conservation potential was forecast to come from improvements in lighting. Lighting 

was estimated to make up about 45 percent of commercial sector electric use in 1983. Lighting 

power density, as measured by watts per square foot, is one metric that can be used to gauge the 

progress in lighting efficiency over time. Table 5 compares the lighting power densities for four 

major building types forecast to be achievable in the Council’s 1983 Plan through adoption of its 

Model Conservation Standards for New Commercial Buildings with the current requirements of 

the commercial energy codes in the region. Table 5 shows that for office buildings and schools, 

current code requirements far exceed the levels of efficiency forecast to be achievable in 1983. 

For retail stores and warehouses, the 1983 Plan’s assessment of achievable efficiency levels 

appears to be very near current code requirements. Offices, schools, retail stores, and 

warehouses make up about 60 percent of total commercial sector building floor space. 

In addition to lower lighting power densities, the 1983 MCS also made recommendations on 

several lighting-control measures that have largely been adopted -- or exceeded in local codes 

throughout the region. The 1983 MCS included switchable lighting circuits that would allow 

manual or automatic control to turn off half the lighting circuits in spaces over 400 square feet. 

Current energy codes in all four states have adopted similar or superior provisions. The 1983 

MCS called for automatic controls on outdoor lighting to turn lights off during daylight hours. 

That measure has been adopted in all local codes in the region. The 1983 MCS also required 

lighting circuits be designed to accept manual or automatic day lighting controls for areas within 

12 feet of windows in office and school spaces. That measure is in code in Washington. In 

addition, current energy codes go much farther in lighting controls than was anticipated in the 

1983 MCS. For example, occupancy sensors are required in Oregon and Washington on certain 

classroom, office and conference spaces. Automatic night-time control of interior lighting is 

required in all four states for all but the smallest buildings.

 

10 ECONorthwest, Market Progress Evaluation Report, No. 1 (E02-101), prepared for NEEA June 20, 2002. 

 

Council document 2007-7 14
Table 5 

Commercial Building Maximum Lighting Power Densities in 1983 Commercial Model Conservation 

Standards and Current Regional Energy Code Requirements 

Lighting Power Density (watts/sq.ft.) 

Building Type 1983 Commercial 

MCS 

OR 2004 WA 2004 ID & MT Seattle 2004

Office buildings 1.5 1.0 1.0 1.0 1.0 

Retail Stores 1.5 Varies

1.5+ 

Varies

1.5+ 

Varies 1.5+ Varies 1.5+ 

Schools 2.0 1.1 1.35 1.2 1.2 

Warehouses 0.7 0.5 0.8 0.8 0.5 

 

Lighting improvements for existing commercial buildings show similar trends of exceeding 1983 

estimates of conservation potential. Two extensive surveys have been conducted to assess the 

energy-related characteristics of existing commercial buildings in the region. The first was 

carried out in 1987, about five years after the 1983 Plan was adopted. The second was 

completed in 2002. Table 6 shows the average lighting power density of the sample of existing 

buildings in 1987 and these same buildings in 2001. During this time period lighting power 

density was reduced by 20 percent across all buildings and from 13 to 21 percent in office and 

retail buildings. The 1983 Plan did not estimate lighting conservation potential specifically for 

existing commercial buildings. But overall electric conservation potential was identified as 

about 28 percent of electric use in 1982. By 1987, utility programs had already started to take a 

bite out of the conservation potential identified in 1983. Lighting represented about 45 percent 

of electricity use in commercial buildings in 1983. So a 20-percent reduction in existing lighting 

power density in the 14 years between 1987 and 2001 represents at least a 10-percent reduction 

in overall electric use for older buildings. Because lighting represents 45 percent of all 

commercial uses of electricity, the 25-percent reduction in lighting power density shown in Table 

6 for existing buildings translates into 11 - 12 percent overall building efficiency improvement. 

Table 6 - Change in Lighting Power Density for Existing (Pre-1987) Buildings Between 1987 and 2001 

 Lighting Power Density 

(watts/sq.ft.) 

Reduction in Lighting Power Density (%) 

Audit/Survey Date All 

Buildings 

Offices Retail All 

Buildings 

Offices Retail 

As found in 1987 1.5 1.6 1.9 

As found in 2001 1.2 1.4 1.5 20% 13% 21% 

Another gauge of lighting improvement is to look at the huge technological improvement in 

lighting efficacy, particularly fluorescent lighting, which accounts for about two thirds of 

commercial lighting. At the time of the 1983 Plan, improvements in lighting were available 

through improved fixture design, reduced lighting levels, and conversion from incandescent 

lighting to fluorescent or other high-efficiency lighting. Only modest improvements, on the 

order of 10 percent, were available in the efficacy of fluorescent light sources themselves -- the 

lamps and ballasts. But since 1983, improvement in the efficacy of fluorescent light sources has 

Council document 2007-7 15
doubled. Figure 8 shows fluorescent source efficacy, as measured by lumens of light output per 

watt of electric input. Source efficacy for fluorescent lighting, the ability to turn electricity into 

light, increased from 47 to 94 lumens per watt over the twenty years from 1982 to 2002. In 

1987, typical office lighting power density was about 2.0 watts per square foot11. By combining 

the 50-percent improvement in fluorescent source efficacy with additional improvements in 

fixture design, reduced lighting levels, and conversion from incandescent lighting to fluorescent 

lighting and other high-efficacy sources, it is clear why new office lighting designs can get to 0.7 

watts per square foot, about one-third of what they were in 1983 and well below what was 

thought possible at the time. 

Figure 8 - Typical Fluorescent Source Efficacy

0

10

20

30

40

50

60

70

80

90

100

1980 1985 1990 1995 2000 2005

Year

Efficacy i

n L

u

m

e

n

s p

er W

att

In addition to improvements in lighting efficiency, the 1983 Plan forecast achievable savings 

from increases in the efficiency of heating, ventilating and air conditioning (HVAC) equipment. 

Table 7 compares the 1983 Plan’s expected minimum efficiency requirements for cooling 

equipment efficiency levels with the minimums have been required by code in all states in the 

region since 2001. What is clear is that current minimum efficiency requirements far exceed 

those envisioned as achievable in 1983. The minimum efficiency requirements (SEER) for 

cooling equipment under 65,000 Btu/hr in all Northwest states is 66 percent above that expected 

in the 1983. Similarly, for larger equipment the minimum efficiency requirement is 22 percent 

above that anticipated for 2002 in the 1983 commercial MCS. 

 

11 PNNonRes Phase II Results, Table 10c 

Council document 2007-7 16
Table 7 - Commercial HVAC Equipment Efficiency Specifications

Capacity Under 65,000 Btu/hr Capacity 65,000 Btu/hr and 

Larger 

 

System Type 

1983 Achievable 

SEER12

Current Code 

Minimum SEER 

1983 Achievable 

EER13

Current Code 

Minimum EER

Air Cooled 7.8 13.0 8.2 11.0 

Irrigation Sector 

In 1982 total irrigated acreage in the region was roughly 8.9 million acres and irrigation

electricity use that year was 695 average megawatts or 655 kilowatt-hours per acre per year. In 

2002 the irrigated acreage in the region was virtually unchanged from 1982 while electricity used 

for irrigation had dropped to 595 average megawatts or 579 kilowatt-hours per acre per year. 

The 1983 Plan assumed that if all achievable efficiency measures (e.g., reduced pressure, center 

pivot sprinkler systems) and practices (e.g., irrigation water scheduling) were implemented by 

2002, electricity use for irrigation would drop to 596 kilowatt-hours per acre per year. Actual 

irrigation efficiency gains, therefore, slightly exceeded those forecast in the 1983 Plan. 

Industrial Sector 

Energy efficiency progress is difficult to measure on a broad scale in the industrial sector. 

Confounding issues include the changing mix of industries, products, and feedstocks, the general 

lack of applicable codes and standards, and the ability to substitute fuel and electricity in some

processes. In 1983 the Council’s forecast of achievable conservation potential was equivalent to 

about 6 percent of non-DSI industrial electric loads. Incremental improvements in minimum 

efficiency levels for electric motors alone have yielded a good share of that potential over the last 

twenty years. Motors comprise something on the order of 60 percent of industrial energy use. 

Minimum efficiency standards now in place are a 3 to 10 percent improvement over 1983 

efficiency levels for motor sizes covered by federal standards. 

Further, motor efficiency is a small part of what has been accomplished in the industrial sector. 

There are many industrial plants and processes that have far exceeded a 6-percent efficiency 

improvement by improving their processes and facilities. These include documented 

improvements of 20 to 30 percent in cold-storage facilities, savings of 15 to 30 percent in 

compressed air systems for many plants across different industries, lighting improvements of 

about 50 percent in manufacturing spaces with high ceilings, and many industry-specific process 

changes in the range of 20-percent improvement. In addition, NEEA has operated several 

successful industrial market transformation projects. For example, the NEEA and Siemens 

project on silicon crystal-growing facilities reduced electric power consumption for producing 

 

12 SEER = Seasonal Energy Efficiency Ratio. This is the annual ratio of electricity used per unit of cooling energy

provided. A SEER of 6.826 equals an annual coefficient of performance of 2.0 (6,826 Btu of cooling for each 

kilowatt-hour -- 3413 Btu -- of electricity use) 13 EER = Energy Efficiency Ratio. This is the instantaneous ratio of electricity used per unit of cooling energy

provided. 

Council document 2007-7 17
silicon crystals by 50 percent14. Savings from this project occurred in an industry that barely 

existed in 1983. 

Summary and Conclusions 

There is ample empirical evidence to support retaining the Council’s assumptions for achievable 

conservation potential. Both the 85-percent achievable potential for non-lost opportunity 

resources and the approximately 65-percent achievable potential for lost-opportunity resources 

over a 20-year period are supported by experience of the last 20 years. Further, the Council’s 

assumed near-term achievable acquisition rates are well-supported and may be conservative 

when compared to what has occurred in practice. 

In its 1983 Plan the Council forecast that significant improvements in the energy efficiency of a 

wide array of residential and commercial appliances, equipment and buildings could achieve an 

85-percent market share by 2002. With some exceptions, nearly all of the actual improvements 

in residential appliances and water heating have far exceeded the 1983 Plan’s expectations. In its 

1983 Plan the Council called upon the states in the region to improve residential energy codes by 

approximately 40 percent and commercial energy codes by 10 percent. Before the end of 1992 

the two most populous states in the region, representing over 80 percent of new home

construction and nearly 85 percent of new commercial floor space, had met the savings goals. 

By 2002 all of the states in the region had met the Council’s original residential MCS and 

exceeded its original commercial MCS by at least 10 percent. 

The 1983 Plan forecast that a 43-percent efficiency improvement in new residential refrigerators 

was achievable by 2002. This level of efficiency gain was not only achieved 10 years early 

(1992), but by 2002 new refrigerators used only 55 percent of the energy they did in 1983, even 

though they were both larger and more of them were frost-free. Freezer and dishwasher 

efficiency improvements also far exceed the 1983 Plan’s assessment of achievable potential. 

Freezers met the first Plan’s efficiency target in 1984, and by 2002 these appliances were using 

45 percent less energy that was viewed as “achievable” in 1983. Dishwashers in 2002 used 32 

percent less energy than they did in 1983, far exceeding the first Plan’s goal of a 24-percent 

savings. 

A few conservation measures included in the 1983 Plan, such as residential heat pump water 

heaters, have not yet realized the anticipated penetration. However, savings from measures not 

envisioned in the 1983 Plan, such as those from low-flow showerheads and energy-efficient new 

manufactured housing, more than offset the unrealized savings. 

While the Council staff believes there is ample empirical evidence to support existing 

assumptions of 20-year achievable penetration rates, it is important to note that the 20-year 

forecast window for achievable conservation is less important today than it was in 1983 when 

 

14 Market Progress Evaluation Report, Silicon Crystal Growing Facilities, No. 2, Report #E01-090, prepared by

Research Into Action, Inc., for NEEA, November 2001. 

Council document 2007-7 18
generating resource lead times were long15. New generating facilities and transmission system

expansions now can be brought on line in three to five years. Therefore, the need to accurately 

predict the achievable market penetration rate of an energy efficiency measure 20 years into the 

future is greatly reduced. Much more relevant to present-day resource planning decisions is 

what is achievable in the near term. The pace at which conservation programs can be “ramped 

up” and maintained over the near-term period is critical and of more practical importance than 

20-year forecasts. There is solid evidence, presented here, that near-term achievable 

conservation rates have been higher than the Council’s planning assumptions for both lostopportunity and non-lost opportunity measures. 

The historic effect of codes and standards in comparison to the Council’s 1983 Model 

Conservation Standards reveals that in most cases, Council forecasts of 20-year achievable 

potential for lost-opportunity measures were met or exceeded in 10 years or less. In fact, several 

exceed 100-percent penetration in ten years, far exceeding the Council’s near-term assumption of 

approximately 50-percent penetration in 10 years for lost-opportunity measures. 

There is also ample evidence from utility programs that indicate conservation acquisition 

programs for non-lost opportunity measures can be scaled up rapidly. Figure 9 shows annual 

regional utility program conservation savings from 1980 through 2005. Program savings have 

more than doubled in just one or two years. These increases were driven almost entirely by 

acceleration of programs for non-lost opportunity measures. In the last five years the region has 

maintained acquisition levels of 130-150 average megawatts per year. Retrofit conservation 

comprises 110-120 average megawatts per year of that total. If that pace were maintained, it 

would take 12 to 14 years, not 20, to reach the 85-percent penetration rate for the 1,500 average 

megawatts of cost-effective non-lost opportunity conservation identified in the Fifth Power Plan. 

Figure 9 - Annual Utility Program Conservation Savings

1980 - 2005

0

20

40

60

80

100

120

140

160

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

Year

Savings (aM

W)

 

15 The rationale for selecting a 20-year perspective for realistically achievable conservation in the 1983 Plan

stemmed from the fact that at that time it took as much as 15 years to construct major central-station generating

facilities. Therefore, both load forecasts and resources plans had to predict when construction should start far in 

advance of actual need. 

Council document 2007-7 19
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