Emerging Energy-Saaving Technologies and Practices for the Buildings Sector

Steven Nadel, Leo Rainer, Michael Shepard, Margaret Suozzo and Jennifer Thorne

December, 1998

Executive Summary

In 1992, the American Council for an Energy-Efficient Economy (ACEEE), the Davis Energy Group (DEG), and E Source prepared a study on Emerging Technologies to Improve Energy Efficiency in the Residential and Commercial Sectors. This study, published in 1993, profiled and analyzed more than 100 energy saving technologies that had been recently commercialized or were expected to be commercialized over the next decade. It brought many technologies to the attention of utilities, government agencies (e.g. DOE and EPA), and other energy-efficiency professionals, and has contributed in a substantial way to existing market transformation initiatives.

The current report, sponsored by the Association of State Energy Research and Technology Transfer Institutions (ASERTTI), updates and expands this earlier work. This study aims to:

• Identify new research and demonstration projects that could help advance high-priority emerging technologies;

• Identify potential new targets for market transformation activities;

• Provide a common foundation of information on emerging technologies to a wide array of state and federal agencies, utilities, utility R&D organizations, and public-interest organizations in order to help further joint activities among these agencies and organizations; and

• Offer new insights into the technology development and commercialization process by comparing 1993 expectations with 1998 realities.

Scope

The project scope includes measures used in and on residential and commercial buildings. Industrial and agricultural options are not considered here. Technologies (e.g., a new air conditioner) and practices (e.g., improved air conditioner installation procedures) as well as more efficient or renewable energy sources or fuel-switching measures that save energy on a primary basis are included.

For purposes of this study, "emerging technologies and practices" are defined as those that are either: (i) not yet commercialized but are likely to be commercialized and cost-effective to a significant proportion of end-users (on a life-cycle cost basis) by 2005; or (ii) commercialized, but currently have penetrated no more than 2 percent of the appropriate market. Measures with only long-term potential as well as measures that have already shown significant acceptance in the market are excluded from analysis.

Approach

The project team used an eight-step approach to analyze measures considered in this study. First, lists of measures that fall within the project scope were compiled. Second, these measures were divided into preliminary high, medium, and low potential lists based on prior analyses on measure cost-effectiveness and potential savings. Third, limited research was conducted on medium potential measures to determine whether these should be moved to either the high or low potential lists or remain on the medium potential list. Fourth, nearly 80 measures were selected for more detailed research, including all high and medium potential measures as well as a few lower potential measures that were of particular interest to the project sponsors. Fifth, more detailed research was conducted on the selected measures and the results compiled into written summaries and numerical database entries. Sixth, data on the selected measures were examined and more refined criteria developed to distinguish high priority measures from medium-high and medium- low priority measures. Seventh, the results of this study were compared to the previous 1993 Emerging Technologies study in order to examine trends and lessons learned. And finally, all of the data were compiled into this written report and a companion database.

Caveats and Limitations to the Analysis

When interpreting the results of this analysis, a few caveats should be considered:

Data for emerging technologies are often imprecise. Since many of the technologies and practices covered in this report either have not yet been commercialized and are just niche products, estimates of items such as measure cost, savings, and commercialization date are generally imprecise. The project team has chosen to round figures for the cost of saved energy and savings potential ratings to one significant digit as finer distinctions would be meaningless.

Data quality varies considerably among measures. Data reported should be viewed as the midpoint of a range, with endpoints between 10 and 50 percent higher and lower than the midpoint, where the size of the range varies with the quality of the data available. In some cases data were obtained from several sources and there was general agreement between sources as to specific data values. In other cases, data were based on only preliminary estimates obtained from only one source, often a source with a vested interest in promoting the product. A data quality indicator is included with each measure to aid in interpreting the data.

Costs and savings will vary with application. The analyses described in this report are for "typical" applications; savings and costs are likely to be different for buildings that differ significantly from the average. This is particularly true when examining heating and cooling measures.

Each measure was examined independently without regard to the other measures. As a result, there is extensive overlap in the savings estimates between measures and thus the savings from different measures listed in this report are not additive.

Only applications of these measures in the buildings sector were examined. Many of the measures are also suitable in other sectors such as the industrial sector. In some cases, savings, cost-effectiveness and likelihood of success are greater in these other sectors than in the buildings sector. Thus, some of the measures rated "low priority" in this study may have higher priority if applications in other sectors are considered.

Results

Savings and cost of saved energy for all of the individual technologies examined for this report are summarized in Table E-1. This study identified a total of 12 high-priority and 21 medium-priority emerging technologies and practices. Taken together, these measures have enormous potential to reduce energy use in the U.S. Savings opportunities appear to be most pronounced in three areas: HVAC, lighting, and integrated new building design. However, potential savings are also substantial in other end-uses including appliances, water heating, on-site power production, and building shell.

Of the 12 high-priority technologies and practices, 9 are primarily residential and 3 are principally commercial sector measures. All but 4 of the 12 have already been commercialized, but are currently difficult to find, and commercialization is anticipated for the remaining 4 measures over the next few years. Of the 21 medium-priority measures identified, 12 are residential technologies, 8 are primarily commercial sector technologies, and 1 applies equally to both sectors. Again, most of these measures have been commercialized but, as with the high-priority measures, some of these could benefit from additional research and development.

Recommended next steps for these high- and medium-priority technologies are outlined in Table E-2. For most measures, several follow-up steps are recommended. In particular, most of these measures can benefit from additional tests/demonstrations and from increased education/training/promotion activity. Some measures can also benefit from additional research and development, from financial incentives, and/or from new/revised codes and standards.

Comparison to the 1993 Emerging Technologies Study

Many of the measures examined in the 1993 report were reexamined in this new study. Of the more than 60 measures from the 1993 study considered in the initial screening, 21 measures made the final list of measures in the current report. For these measures we compared our 1998 findings with our 1993 expectations. We found in multiple cases that energy savings estimates are lower in 1998 and that commercialization dates have been delayed, which indicates that projections of energy savings and commercialization date have a tendency to be optimistic for technologies that are not yet commercialized. New information about costs and savings, limited feasible applications, and more conservative assumptions about these parameters (where information was sparse) resulted in a reduction in the priority for several of these measures (e.g., from a high-priority measure in 1993 to a medium- priority measure in 1998). In addition, several of the top priority measures from the 1993 study are not included in this study because they now occupy more than a 2 percent market share, have an expected commercialization date beyond 2005, offer small energy savings, or have a high cost of saved energy.

Recommendations

Based on the research described in this report, the following actions are recommended:

• Begin pursuing the next steps to advance the high-priority measures as well as many of the medium-priority measures.

• Continue to track and evaluate the success of efforts to advance these technologies, so that approaches for advancing emerging technologies can continue to be refined.

• Conduct an emerging technologies assessment for the industrial and agricultural sectors. Given the large amounts of energy that are used in the industrial and agricultural sectors, a study examining emerging technologies for these sectors is likely to be rewarding. A major focus of this study should be on process energy use.

• Reexamine emerging technologies for the residential and commercial sectors in approximately three years. New technologies are in a constant state of flux. The status of many of the technologies listed here may change over this period of time and up-to-date information on costs, savings, and current status should be collected.