### State-Level Energy Efficiency Analysis : Goals, Methods, and Lessons Learned

Maggie Eldridge, R. Neal Elliott, and Max Neubauer, American Council for an Energy-Efficient Economy

ABSTRACT

The past few years have seen a resurgence of interest in state-level energy efficiency

studies. These studies have been undertaken fo r a range of reasons and have had a variety of scopes and approaches—some more effective than others. In the interest of sharing lessons learned and developing effective strategies for st ate-level analyses, this paper will first review recent studies done by others to examine themes in approaches and scope, a nd then look at recent

studies that the authors have been involved with and explore their goals, approaches and effectiveness. Based on these experiences, the au thors will present their recommendations on: guidance on identifying the goal/goals for the study; what are the appropriate scopes and methods to meet different goals; and what other pr oject elements are critical to an effective study release. In addition, the authors di scuss some of the data and analyt ical challenges that are faced by state-level energy efficiency assessments and how the analysis results are most effectively presented to a state-level policy audience.



### Introduction

An energy efficiency potential st udy is a tool to help states advance smart energy policies and programs by providing critical data resources th at inform decision makers. These studies are typically a first step taken by stat es interested in building the cas e for efficiency policies. A study could support a number of state needs for designi ng efficiency policies and programs, such as setting energy savings goals, inco rporating energy efficiency in to the integrated resource planning (IRP) process, or determ ining funding levels for efficiency programs and policies. The Environmental Protection Agency’s (EPA) Guide for Conducting Energy Efficiency Potential

Studies (see EPA 2007) is an excelle nt resource for parties inte rested in advancing energy efficiency in their own stat e, region, or program area. In recent years, there has been a resurgence of in terest in state-level energy efficiency studies. In 2007, ACEEE completed en ergy efficiency potential analys es for the states of Texas, Florida, and Michigan (Elliott et al. 2007a&b; La itner & Kushler 2007). Similar studies were recently completed for Utah (Gel ler et al. 2007), California (I tron et al. 2007), North Carolina (GDS 2006) and others. Following the publicati on of the Florida and Te xas studies, several

additional states contacted ACEEE re questing a similar study for thei r own state. In response to this surge in interest, ACEEE launched its State Clean Energy Resource Project (SCERP) in the fall of 2007, with the goal of completing about four state studies each year for the next 3 years. In 2008, ACEEE completed a study for Maryland (Eld ridge et al. 2008) an d plans to complete studies for Ohio, Virginia, and Pennsylvania by the end of 2008 or early 2009. Based on these experiences, and past experien ce dating to the late 1980s, ACEEE has gained some important insights into how to effectively plan, undertake and use these state potential studies. We will attempt to share these lessons learned in hopes of increasing the effectiveness of future efforts.

8- 63 2008 ACEEE Summer Study on Energy Efficiency in BuildingsThe numerous energy efficiency potential studi es that have been conducted over the past decades have played an important role in motivat ing and shaping energy policies at both the state and national level. In this paper, we will first the review the elements of an efficiency potential analysis and examine the approach of several r ecent efficiency studies. Then, we explore how experiences with these studies have lead ACEEE to identify and provide insights on the following elements of a successf ul and effective analysis:

• Clearly identify goals that th e study is intended to achieve

• Match the level of analysis to goals

• Engage stakeholders early in the analysis process

• Match analysis to available data

• Plan for and implement an effective media strategy

• Plan and budget for analysis follow-up



### Elements of a Potential Analysis

While energy efficiency potential analyses have been prepared for decades, there has been some inconsistency in how the studies have been conducted and how terms are defined. Our meta-analysis of efficiency potential stud ies (Nadel, Elliott and Shipley 2004), and recent updates in 2006 and 2008 (report forthcoming) rev ealed these differences in term definitions. These reviews did find, however, that a comm on approach was generally used. Our recent studies, however, have found that th is “traditional appro ach” is not always the most effective for

some purposes.

Traditional Approach

In the traditional approach of energy effici ency potential studies, there are three broad categories of efficiency potential: technical, economic, and achievable. These are generally characterized by the following definitions:

• The technical potential represents an ideal scenario which sums all energy efficiency

measures that are feasible given technology limitations. The technical potential bears no consideration of technology costs.

• Economic potential represents the fraction of the techni cal potential that is cost-effective, which can be evaluated in several ways. So me options include the Total Resource Cost (TRC) test or, from the consumer’s perspectiv e, such as a participant’s cost of saved energy (CSE).

• Finally, the achievable potential represents a fraction of th e economic potential that is attainable given actual program infrastructure and both societal and market limitations.

Recent Studies

ACEEE recently reviewed seven state and region al potential studies in addition to those we reviewed for our 2004 meta-analysis (Nad el, Elliott and Shipley 2004): California (Itron 2006), New England (Dunksy Energy Consultin g 2005), New Mexico (GDS 2005), North Carolina (GDS 2006), Québec (Optimal Energy 2004) , Utah (SWEEP 2007) , and Vermont (GDS

8- 64 2008 ACEEE Summer Study on Energy Efficiency in Buildings2007). The New Mexico study focused solely on an alyzing potential savings from natural gas energy-efficiency programs, while the California, New England, and Utah studies incorporated both electricity and natural gas into their analyses . Most of these studie s were conducted at the behest of state governm ents (New Mexico, North Carolina, Utah, and Vermont); the rest were commissioned by non-governmental organizatio ns (California, New England, Quebec). The scope, detail, and duration of these studi es vary significantly. Four of the studies analyze the technical, economic, and achievable potential across all sectors of the economy, whereas three of the studies focus solely on achie vable potential. Five of the studies aggregate achievable potential across all sectors, which is th e estimate that policymakers consider to be the most important when analyzing st ate efficiency potential. The definition of "achievable potential" varies among studies, which necessitates a rigorous perusal of the methodologies. For ex ample, the North Caro lina and Vermont GDS

studies refer to the "Achievable Cost-Effective Po tential," which they define as the "realistic penetration of energy efficient measures that ar e cost-effective [...] and would be adopted given aggressive funding [...]" The GDS New Mexico study refers to ach ievable potential as

"Maximum Achievable Cost-Effective Potential" and defines it as "the potential for maximum penetration of energy efficient measures that ar e cost-effective [...] and would be adopted given unlimited funding [...]"Optimal Energy’s study of New England similarly refers to achievable potential as "the potential for maximum market penetration of en ergy efficient measures that are cost-effective [...] and that would be adopt ed through a concerted, sustained campaign [...]"Achievable potential savings for electricity across all sectors in these studies ranges from 0.6% (Itron 2006) to 4% (Op timal Energy 2004) per year beyond normal reference case improvements (see Figure 1). The Utah study (SW EEP 2007) takes a slightly different approach, modeling several policy scenarios and estima ting the energy and economic impacts of the policies, and estimates about 1.7% savings per year. This is si milar to the policy scenario approach used in ACEEE’s recent state studies , which is discussed in the next section. The majority of the studies utilize the Total Resource Cost (TRC) test to determine costeffectiveness when estimating economic and achi evable potential savings. Two studies, North Carolina and Quebec, rely on a levelized cost of conserved energy (CCE) as the metric for measuring cost-effectiveness. ACEEE’s recent stat e studies use this same approach, with costeffectiveness defined as having a CCE less than the end user’s retail cost of energy. The Vermont study uses a societal cost test, which quantifies the benef its, such as reduced emissions, and costs to society as a whole as opposed to just util ities and ratepayers. All of the study results show net positive benefits for the measured efficiency potential. Table 1 shows the results of several electricity efficiency potential studies from the past eight years, most of which follow the traditiona l approach outlined above. The recent ACEEE studies and the SWEEP 2007 study followed a slightly different “policy scenario” approach for estimating achievable potential, as is discusse d in the next section. Th is figure incorporates results from the 2004 meta-analysis by ACEEE (see Nadel, Elliott and Shipley 2004), a few studies completed in 2005 and late 2004, and a recent update in 2008. The meta-reviews also examined natural gas studies, though we present electricity study results he re only. The average study identified an electricity savings tech nical potential of 2.3%, 1.8% economic, and 1.5% achievable, averaged annually ov er the study time period. Studies that did not include one or more of a type of potential were not incorporated into the average annual percent savings for that specific type of potential.

8- 65 2008 ACEEE Summer Study on Energy Efficiency in BuildingsTable 1. Meta-Analysis of Electricity En ergy Efficiency Potential Study Results

Total Efficiency Potential over Study Time Period (%) Average Annual Efficiency Potential (%)

Region of Study Technical Economic Achievable Study Time

Period (years) Technical Economic Achievable

U.S. (2000) NA NA 24% 20 NA NA 1.2%

Mass. (RLW 2001) NA 24% NA 5 NA 4.8% NA Calif. (Xenergy/EF 2002) 18% 13% 10% 10 1.8% 1.3% 1.0% Southwest (SWEEP 2002) NA NA 33% 17 NA NA 1.9% NY (NSERDA/OE 2003) 36% 27% NA 20 1.8% 1.4% NA Oreg. (2003) 31% NA NA 10 3.1% NA NA Puget (2003) 35% 19% 11% 20 1.8% 1.0% 0.6%

Vermont (2003) NA NA 31% 10 NA NA 3.1% Quebec (Optimal 2004) NA NA 32% 8 NA NA 4.0%

NJ (Kema 2004) 23% 17% 11% 16 1.4% 1.1% 0.7%

Conn. (GDS 2004) 24% 13% NA 10 2.4% 1.3% NA New England (Optimal 2005) NA NA 23% 10 NA NA 2.3% Northwest (NW Council 2005) 25% 17% 13% 20 1.3% 0.9% 0.6%

Georgia (ICF 2005) 29% 20% 9% 10 2.9% 2.0% 0.9%

Wisc. (ECW 2005) NA NA 4% 5 NA NA 0.7%

Calif. (Itron 2006) 21% 17% 8% 13 1.6% 1.3% 0.6% North Carolina (GDS 2006) 33% 20% 14% 10 3.3% 2.0% 1.4%

Florida (ACEEE 2007) NA 25% 20% 15 NA 1.7% 1.3%

Texas (ACEEE 2007) NA 30% 18% 15 NA 2.0% 1.2%

Utah (SWEEP 2007) NA NA 26% 15 NA NA 1.7%

Vermont (GDS 2007) 35% 22% 19% 10 3.5% 2.2% 1.9%

Average NA NA NA NA 2.3% 1.8% 1.5%

As noted in Nadel, Elliott and Shipley (2004 ), the technical poten tial is a somewhat problematic construct because it is intended to capture all the efficien cy opportunities available without consideration of the cost of implemen ting the efficiency improvements. In reality, analysts may restrict their assessments to measur es they think will likely be cost-effective, and

therefore blends the traditional definition of econo mic and technical potential. As a result, the actual estimate is only a partial estimate of the technical potential, and is not particularly meaningful in a policy context. ACEEE’s recent studies for Texas, Flor ida and Maryland have not included an assessment of technical potentia l but rather focus specifically on the economic, or cost-effective, potential. In addition, rath er than an assessment of “achievable” potential,

which is defined in a number of different ways among study authors, we now estimate the impacts of what we term a “policy scenario.” In the next section we suggest this alternative approach as an effective means of informing policymakers at the state and regional levels.

8- 66 2008 ACEEE Summer Study on Energy Efficiency in BuildingsAlternative Approach

Recently, ACEEE has taken an alternative appr oach to the traditional energy efficiency potential studies, one which has been successful for our recent energy efficiency studies for Florida, Texas, and Maryland. Keeping in mind that the audience for these state analyses, including policy makers and state advocates, is not familiar with the traditional language of efficiency potential studies, th is framework moves away from th e terms described above toward what we hope is a more transparen t discussion to a lay audience. First, we substitute the term “efficiency resource assessment” for “economic potential.” This construct puts demand-side energy efficiency in the sa me framework as supply side

resources. The same metrics of cost-effectiv eness apply, though it helps to frame energy efficiency as a resource similar to the manner in which utilities assess the potential for new generation or transmission resources. EPA’s guide for potential studies de scribes this type of analysis as requiring mid-level detail and time to complete (EPA 2007). We discuss in the next section the range of analysis levels of detail. Second, we perform a policy scenario asse ssment by modeling a specific suite of efficiency policies that can be implemented at th e state-level. These typically include building energy codes, appliance efficiency standards, combined heat and power (CHP) initiatives, and energy efficiency resource standards (EERS) , among others. The policy assessment draws upon the overall efficiency resource assessment for data on costs and savings potential for policies. Again, by framing the analysis from the state polic ymaker’s standpoint, we offer actions that are understandable and can be readily implemented. In addition to the energy impacts of the policy scenario assessment, our state studies also ex amine the macro-economic impacts, i.e. jobs, consumer energy bill savings, wages, and GSP, using a input-output model called DEEPER (see Laitner et al. 2007). These resu lts are highly effective for informing state policymakers’

discussions of benefits to th e state from energy efficiency. This alternative approach provides effective framing for policymakers, a key audience for many efficiency studies. In addition, this approach offers flexibility to use different levels of analysis, depending on the needs of a state’s specific request. We discuss later how to identify the appropriate level of analysis.



### Identifying the Goals of an EE Potential Study

The first steps in undertaking an efficiency potential study are to identify the following: why has the study been requested (or what the goals are), who is your audience, and what is the scope of the analysis.

It is crucial to first have a clear understa nding of why the study is being undertaken. In other words, what is the ultimate goal? Is the study to support legislation and/or regulatory hearings? Is it to establish energy savings targets or levels of funding for efficiency investments? Is it to develop specific efficiency programs? Once the need is defined, the next thing to be considered is: has there already been an efficiency potential study done for the state or region? If so, does the existing study meet the need driving the request? Only if these last

two answers are no should a st ate or region pursue its own energy efficiency potential assessment. Then, understanding why the study is be ing undertaken will be the key driving force behind the level of analysis needed, whic h is discussed in the next section.

8- 67 2008 ACEEE Summer Study on Energy Efficiency in BuildingsNext, who is the audience for the study? Who are the players that can use the critical data provided in a potential study to help make the goal happen? Typical audiences for efficiency potential studies are policymakers, state ag encies, advocacy organizations, and program implementers. Understanding who your audience is will help drive the focus and framing of the analysis. Engaging key stakeholders, which is di scussed shortly, is an important part of this

process. Finally, what is the scope? This includes th e sectors and fuel types analyzed, analysis time period, and the necessary information on costs and benefits. Scope is largely dependent on the region and the specific needs of the state requesting the study. Recently, our studies have focused primarily on electricity and peak demand in the residential, co mmercial, and industrial sectors, though we have also received requests for natural gas and oil savings, onsite renewable energy, and transportation. Many policy makers and consumers do not differentiate between different energy markets and type s of energy the way most ener gy experts do, so a restrictive

focus can create confusion for a broader audience.



### Levels of Analyses

There is no one size fits all for state-level e fficiency assessments—they can vary in their level of detail and complexity of the analysis. ACEEE has found th at assessments fall into three broad categories: high-level, pol icy scoping; policy planning and analysis; and detail program planning and targeting. The EPA efficiency potential study primer (EPA 2007) very similarly captures these levels of analyses, from low deta il to high, as: building the case for efficiency; identifying alternatives to s upply-side investments; and detailed planning and program design; these are captured as a continuum graphically (see Figure 1). Understanding the goals for a potential study is crucial to inform the level of analysis, and can help deter spending more time and money than is needed or investing in a study that does not provide the level of detail needed.

High-Level Policy Scoping

These analyses draw upon publicly available data and past program experiences to provide a first-order indi cation of the magnitude of the energy efficiency resource available in a state at the sector level (e.g., residential, commercial and indus trial). These studies can be completed fairly quickly and cost in th e range of $25,000 to $50,000. These studies are appropriate to beginning a discussion of the role of energy efficiency resources in a state’s energy policy portfolio.

8- 68 2008 ACEEE Summer Study on Energy Efficiency in BuildingsFigure 2. Considerations for Determining the Appropriate Level of Analysis

Source: EPA 2007

Policy and Planning Analysis

These assessments have a greater level of de tail, providing a more de tailed desegregation of energy efficiency resources and the policie s and programs that could be implemented to realize the efficiency potentia l. These studies—ACEEE’s study of Maryland (Eldridge et al. 2008) is a good example—take five to six m onths to complete and can cost between $100,000 and $150,000 depending on scope. These assessments are appropriate for informing state-level policy development.

Detailed Program Planning and Targeting

These highly detailed analyses are intended to inform the design and implementation of individual energy efficiency programs. Key sector and m easure opportunities are assessed, detailed suggestions are made on specific prog ram approaches, and key market allies are

identified. These assessments are intended fo r program administrators and may not be comprehensive, focusing only on key markets th at have been already identified for program development. These analyses can be very time consuming, depending upon the amount of original field data collection th at is undertaken (e.g., equipment saturation surveys), and because the scope varies so much their cost can range from $100,000 to well over $500,000.



### Stakeholder Engagement

One of the frequently overlooked elements of state-level potential studies is stakeholder engagement prior to the start of the data collec tion and analysis. While this may not seem an analytical task, it is critical to developing an effective assessment. Clearly, understanding what policies are politically te nable among the key stakeholders is important. In addition, one should

consider what data sources are credible among the various stakeh olders. We have encountered

this latter issue with reference forecasts of en ergy consumption and energy prices., For example, the electricity and capacity forecast released by the Florida Reliabili ty Coordinating Council (FRCC), which is a regional organization of the No rth American Electric Reliability Corporation

8- 69 2008 ACEEE Summer Study on Energy Efficiency in Buildings(NERC), was deemed more favorable among in-state players, particularly the utilities, than the Florida Public Service Commission’s (FPSC) publis hed forecast. Choosing an accepted forecast can confer credibility to the analysis with these audiences. One less intuitive aspect of the process is using in-state experts. While this would seem to confer credibility to the assessment, we have found that this frequently creates unanticipated political complications. Most in -state subject matter experts are also involved with state-level programs and policies, and their involvement with the team can create unanticipated credibility problems. For example, in one study our renewa ble expert was represen ting the industry in a state proceeding causing some groups to discount the analysis because it was perceived as being prepared by an “advocate.” Havi ng national-level experts can conf er a level of independence to the study that can increa se its effectiveness.



### Data Limitations and Recommendations

One of the biggest challenges ACEEE has faced in undertaking efficiency potential studies has been the availability of consistent data and forecasts for states. This problem is common in most states we have analyzed, and results from a combination of factors. The movement in the 1990s toward utility restructur ing not only resulted in the suspension of most energy efficiency utility programs, but also led to termination of many energy data collection and market surveying activities. This problem is not unique to states. Budge t cuts over the past

decade have resulted in the termin ation of important data sources by federal agencies such as DOE’s Energy Information Administration and the U.S. Census Bureau. While collection of original survey data is always an option, this increases the time and budget significantly, and may not be warranted fo r a policy-focused study. Although there is some regional data availa ble from public utility commissions and nonprofit energy efficiency organizat ions, often, especially for the commercial sector, we need to use regional data from EIA to derive estimates fo r data not available at the state level. Even regional data from EIA, however, is badly out of date. For example, although EIA’s Commercial Building Consumption Survey (CBE CS) was updated in 2003 (EIA 2005), it has not examined electricity consumption at the end-us e level since its 1995 vers ion (EIA 1997). There is also very little detailed state-level energy data for the indus trial sector. This lack of data is a particular problem because of the variation in the nature of the efficiency resource among different, individual industries within a state. As a result, ACEEE has been forced to rely upon national energy intens ity and state and regional economic in formation (see Eldridge et al. 2008 for a discussion of this approach). A key recommendation to states is that, if they are serious about realizing the benefits of energy efficiency resources, the states and u tilities must be focused and strategic about identifying data needs and following through on colle ction of these data resources. They should work together to develop and implement a coordi nated plan for collecting this information in order to effectively design and evaluate the performance of efficiency programs. To accomplish this task, a state agency such as the public utilit y commission or state energy office should be designated as the energy data coordinato r for the state. While some utilities are resuming the collection of some of this data, it is important that the collection is comprehensive and consistent across the state. This entity should cons ider developing data resources including the following:

8- 70 2008 ACEEE Summer Study on Energy Efficiency in Buildings• A consensus statewide electricity and peak de mand reference forecast on which to base the current and future efficiency targets.

• Appliance saturation surveys (similar coordi nated surveys conducted by each utility, or perhaps a single survey with each utility on the stakeholder list and the study designed to provide utility-specific breakdowns).

• New construction baseline surveys (e.g., a st atewide survey with utility-specific information). These should include building si ze and key features suggestive of energy efficiency.

• End-use load-shape studies to help identify the contribution of each major sectoral enduse to peak electrical demand. Power cost s are particularly high during peak demand periods, and understanding and reducing the majo r loads at times of peak demand can be very cost-effective.

• Measurement and verification studies using common methodologies and reporting formats to provide data on program costs and savings.

• Avoided costs to utilities.

By having a single entity with the responsib ility and resources to collect and analyze energy data, states will be able to verify that its policies are achieving their goals, and future analysts will have the necessary data to identify energy effi ciency opportunities and design programs to realize these energy efficiency reso urces. While having good data and forecasts will not save energy by itself, it represents an important enabling infrastructure.



### Effective Media Release Strategy

As important as the analysis of energy efficiency potential is, it will have limited value if the target audiences are not awar e of it. Policymakers get much of their information from general media channels, so media coverage is an important element of the project. ACEEE has learned from experience that most analytical or ganizations do not have th e internal expertise to manage the successful release of a report. For example, ACEEE used an in-state media consultant to support the released of its Flor ida, which proved very effective because the consultant understood how to frame the message so that it responded to local issues and was able to effectively bring the story to the attention of local media leaders. We have used media consultants who have state-specific expertise to support the release of tw o of our recent studies (Florida and Maryland), and achieved much greater earned media coverage than in states where we handled the release or relied upon a local partner organization. Media professionals are called “professionals” for a reason —they focus all of their effort s on planning the study’s release, including framing of messaging, coordination of the press ev ent and follow-on reporting, and placement of op-eds.



### Follow-Up with State

Once a study has been released and the target audiences become aware of it, the authors must then be prepared to respond to the questi ons and requests for additional information. An effective stakeholder engagement process can re duce this somewhat by identifying key issues and responding to them in the report. Howeve r, the study will spark questions that cannot be anticipated. Many efforts underestimate the time and resource requirements, which can

8- 71 2008 ACEEE Summer Study on Energy Efficiency in Buildingscompromise the effectiveness of the effort or cr eate stress for analysis staff. Planning for the required staff time and structuring th e analysis in ways that can a llow the exploration of different scenarios can make this phase of the project much more manageable.



### Conclusions

ACEEE’s recent studies have yielded both si gnificant successes and challenges. In Florida, our study provided a timely framework that was embraced by Governor Charlie Crist who was seeking to address el ectricity supply and global warm ing concerns, and the study showed that energy efficiency represented a least-cost resource that could address these challenges while creating new “gre en-collar” jobs. Among the challe nges, we note especially the potential politics associated with collaborating with in-state play ers, the data limitations, and the transparency of our study results to policymakers. Likewise, our study for the state of Ma ryland provided analytical support for policymakers and aided passage of significant energy efficiency legislation in the state. Again, stakeholder engagement was critical to the proc ess, and could have benefited from even more

time than we allowed. Based on these experiences and others, we have identified several elements, as outlined in this paper, which are crucial to a successful report and dissemination of results. While the focus of preparing a study is fre quently on the analysis and prepar ation of the report, these other project aspects are at least as important: stakeh older engagement, releas e strategy, and follow-up with policymakers. These non-analytical elemen ts can determine how effective and useful a report proves to be to policy makers.



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