Building Technology

Because a kilowatt saved is a penny earned.

Actually, the average cost of 1 KW of electricity in the US as of September 2009 was 12.6¢.  And while this figure doesn’t seem very large, all those cents add up when you consider that an average household consumes more than 34,000 KWH of electricity annually, including about 1200 KWH/Year to run each refrigerator and even more to run a plasma screen TV.  And when you add in the natural gas, fuel oil, kerosene, and wood used to heat houses, run hot water tanks, and operate ovens and other appliances, that’s even more energy consumed and more ways for you to begin cutting your energy costs.

In celebration of National Cut Your Energy Costs Day, which is Sunday, January 10th, FAS has provided a brief list of easy steps  you can  take  to cut your energy use, energy costs, and carbon footprint.  While this list is by no means comprehensive, use it as a starting point to think about how you can begin cutting your energy consumption  today, this month, and over this coming year.  Why not make your New Years resolution to consume less energy in your home?  And as you implement this resolution, we welcome your input into the best ways you have found to reduce your energy consumption and costs.

What you can do today:

-Set your thermostat down to 55 degrees or less at night and when you’re away from the house.

- Caulk and weatherstrip around windows and door that have gaps or where the seam is not adequately sealed.  You can also use a removable caulk to seal windows that you will use in the summer—when the weather warms up, you can just peel off the strip of caulk.

-Reduce “vampire power” in your house by unplugging appliances and electronics when not in use (especially electronics that stay in “stand by” mode such as TVs and computer).

-Visit the Home Energy Saver, an online do-it-yourself energy audit tool that offers advice on how to save energy in your home.  Find it at: http://hes.lbl.gov/hes/.

What you can do this month:

-Upgrade to an Energy Star-rated programmable thermostat if you don’t have one.  Many local utilities and governments will provide and install a free programmable thermostat or will offer a subsidy or tax credits for installing one.

-Have a blower door test done to see where your house is leaking energy.  Many utility companies and some local/municipal governments will offer free or subsidized blower door tests.

What you can do this year:

-Based on the results of your blower door test, add and/or upgrade your house’s insulation.  Insulating around your ducts, in your attic, and in the basement or crawlspace especially is both highly effective and low in cost.

-If it’s time to upgrade your HVAC system, hot water heater, major appliances, or roof, look for Energy Star certified products, which can be found at: www.energystar.gov.  Note that not all Energy Star products are equal and make sure you compare to find those products with the greatest efficiency and lowest operating cost.   Don’t forget to look for state and local tax credits!

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In his speech last Tuesday, President Obama defended the reputation of insulation, stating “See, I told you, insulation’s sexy.”  His assertion that insulation is a hot and sexy building material is based on the cost-effectiveness of insulation for both new construction and retrofits.  And when he stated that “if you saw $20 bills just sort of floating through the window up into the atmosphere, you’d try to figure out how to keep them,” he equates properly insulating a house with saving energy and money.   And we agree—without question, insulation saves energy and money.  Not only is insulation one of the least expensive and best methods of saving money on your utility bills, it also improves your house’s thermal comfort.  So while the Building Technologies Program doesn’t claim expertise at sexiness, we applaud the spirit and message of Obama’s speech.

And insulation is also a key component in the federal government’s energy efficiency strategy.  As the US seeks to reduce energy consumption from buildings in both the residential and commercial sectors, the concept of retrofitting or weatherizing existing building stock has come to the forefront of government policy.  Vice President Biden’s recent report, titled Progress Report: The Transformation to a Clean Energy Economy, backs up the message of the cost-effectiveness and job creation potential of weatherization.  According to the Progress Report, the $5 billion appropriated for the Weatherization Assistance Program (WAP) in the American Recovery and Reinvestment Act of 2009 (ARRA) will weatherize 500,000 houses by the end of 2010 and, combined with private investment, will weatherize 1 million houses by 2012.

In addition to increasing weatherization funding to $5B, ARRA has also increased the percentage of funding that can be used for training (to 20%), raised the WAP qualification cutoff from 150% of the poverty line to 200%, and increased the total per-house weatherization allotment from an average of $2500 to $6500.  This $5B is a good investment not just for the receiving families, but also in terms of job creation.  While the Progress Report fails to provide numbers on how many jobs weatherization should create, it does provide data on the expected job creation from other ARRA energy measures.

Weatherization’s Role in Job Creation

The ARRA cost per job created ratio is a valuable tool for determining which measures are likely to produce the most jobs at the lowest cost.  For example, while public sector investment in energy manufacturing facilities is very capital intensive and yields only one job for every $135,294 invested, renewable energy generation and advanced energy manufacturing is expected to yield one job per $92,490 invested.  By comparison, over the past several years the WAP received $250 million in public funding, directly creating 8000 jobs and weatherizing 100,000 homes annually.  This results in a job creation ratio of one job for every $31,250 of government investment—a highly efficient investment to job ratio. As the budget increases to $5B and the retrofit goal increases to 500,000 houses under the stimulus, the program can be expected to continue as one of the most efficient job creating programs in the clean energy sector.

Assuming that the current weatherization employment was scaled up directly with the additional funding, the additional funding would be expected to produce 160,000 new jobs.  However, several factors will limit weatherization job creation well below this point.

First of all, as more money is spent per house (from $2500 to $6500) houses will be retrofitted with more expensive, less labor intensive measures such as new high-SEER HVAC systems and EnergyStar rated windows.   And so while performing $6500 in retrofits will require more labor than $2500, it will not require over 250% more labor.

Second, as money spent on training and technical assistance increases from 10% to 20% of the budget, less money will go toward directly retrofitting the houses.  However, the higher training and technical assistance appropriation is essential as the nation currently lacks the qualified weatherization professionals necessary to meet the higher weatherization goals.  And without qualified retrofit professionals and specialists, weatherization money will be wasted as installation is not done properly and the program’s full energy efficiency benefits are not realized.

And finally, while the current $5B appropriation is theoretically enough to weatherize the 500,000 house goal at an average cost of $6500, additional program expenses for scaling up operations and state-level training are likely to decease the money available for weatherization wages.

Assuming a ratio of houses retrofitted per job created similar to the 2009 WAP ratio (12.5 houses/job), the program could be expected to create 48,000 jobs.  However, this number is likely to under predict the job creation potential of weatherization as additional retrofit professionals will be needed on each house in order to perform the more extensive retrofit.  Accounting for the additional workers needed to blow interior insulation and replace or repair HVAC systems, doors, and windows, a more realistic ratio would be 9 houses per job.  This yields an estimate of about 70,000 jobs created at $71,429 of government investment per job.  Even this fairly conservative job creation estimate demonstrates the relative cost effectiveness of the WAP and energy efficiency retrofits as compared with other clean energy sector investments.

And at a household level…

The WAP program metrics show that under the $2500/house program households save on average $350 annually on their utility bills, representing a 23% reduction in total utility bills.  This reduction is especially important for low-income families as this sector pays, on average, 16% of their income toward utility bills, as opposed to a national medium of 4-5%.  A key to reducing energy use is to decrease space heating and cooling needs as they together account for on average over 1/3 of a house’s energy use.  And the key to reducing heating and cooling loads?

Insulation.  See, just like President Obama told us, insulation could be a seriously sexy building material.

A few fun facts about insulation and using it in retrofits

What is referred to as insulation is a term for any material that significantly slows down or retards the flow or transfer of heat.  Insulation is measured in terms of its R-value, which is a measure of resistance to heat flow/conductivity.  This equation [DT/Q_A or, in the US, 1 hour* ft²*°F/Btu] measures only conduction, to which 25-40% of air infiltration is attributed in an average house.  The other two means of air infiltration, convection and radiation, make of the remaining 60-75% of air infiltration in a given house, but are not generally considered when looking at the insulating properties of a material. The higher the R-value, the greater the resistance of the material and the better it insulates.

Insulation is classified primarily by form and by material.  Insulation forms, for example, include rigid, semi-rigid, loose-fill, batt, flexible, reflective, and foamed in place.  And common insulation materials include mineral fiber, organic fiber, and foam glass.

While not all types of insulation are appropriate for retrofitting, many interior and exterior/sheathing insulations can be effectively applied.

Surveying the retrofit case studies from the DOE Building America program, the most popular forms of insulation for retrofitting or weatherizing buildings include blown interior and rigid exterior insulations—specifically blown cellulose and polyisocyanurate rigid insulation/board.  Additional types of insulation utilized include fiberglass bat, sprayed polyurethane foam, spray and rigid foams, and rigid insulation integral to both house wraps and siding.  In all cases, the needs of the particular climate must be taken into account, but some form of insulation is almost always the most cost effective retrofit solution.  For example, in Pasadena, “if you have 300 square feet of glass and you replace it, you go from R-1 to R-3 [which is the typical R value for new windows].  For a fraction of the cost, you can take the 2,000-square-feet of ceiling surface area and increase it from R-6 or R-10 to R-38 at the place where it really matters, in the attic.”  (quote courtesty of Andrew Durben at HartmanBalkwin )

The chart below breaks down the cost savings and types of insulation used in six Building America retrofit cases.

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Over the opening days of the Copenhagen Climate Negotiations, which began this Monday, each country has been asked to consider how it can contribute to the 25-40% carbon emission reductions climate scientists believe to be necessary to keep climate change below the 2C mark.  Key issues at stake for the 170 nations represented include commitments to national and international carbon reduction emissions, financing of clean technologies and carbon emission reductions, and technology transfer to non-industrialized nations.   Leading up to the Copenhagen climate summit, deforestation has been primary focus of discussion as deforestation accounts for one-fifth of global carbon emissions and halting deforestation involves large financial investment, but no fundamental consumer behavior changes.  And with a Reducing Emissions from Deforestation and Degradation (REDD) agreement, developed nations would pay developing countries to not cut down their rainforests by treating the standing forest as a valuable commodity.  Such an agreement, if properly financed and implemented, will be necessary to meet global carbon emissions goals and avoid the numerous ecosystem and climate hazards associated with deforestation.

However, in order to meet national greenhouse gas abatement goals and make the economic and structural changes necessary to avoid or mitigate large-scale climate change consequences, industrialized countries must reduce both their total energy consumption and energy intensity.

Consuming 40% of all energy in the US and Europe and 30-40% worldwide, the building sector is one of the least energy efficient sectors and one in which efficiency investment has been generally highly fragmented, relying n the US on individual owners to finance energy efficiency new construction and retrofits.  Yet for many countries, especially the US and the European nations, cutting buildings sector consumption is not only essential to meeting these goals, but is also one of the most cost effective energy saving measures available (see the table from McKinsey, below). Furthermore, analysis by the World Business Council for Sustainable Development (WBCSD) indicates that market-driven reform can reduce building energy use by 60% by 2050, but will require a concerted and immediate effort on the part of industry, government, code and standard making bodies, and labor in order to achieve.

Graph demonstrating the cost effectiveness of buildings energy efficiency (McKinsey)

Looking at energy use in the residential sector as a case study, according to the 2005 Residential Energy Consumption Survey 59% of houses in the US were built before 1980 and in the vast majority of cases have not been substantively renovated or retrofitted. These hugely inefficient houses feature little or no insulation in the attics, walls, and foundations, inefficient HVAC systems, leaky ducts, poor air sealing, outdated windows and doors, and are often expensive to operate due to high energy waste rates, especially during peak heating and cooling periods.

US households spend on average just over $1800 annually on house energy consumption, with over 40% of that energy consumed in maintaining thermal comfort through space heating and air conditioning. However, energy consumption reductions of up to 50% have been proved cost effective in both the retrofit and new housing market by focusing on insulating and air sealing to reduce heating and cooling costs.  In the retrofit market, the efficacy of energy efficiency retrofits in decreasing annual operating costs of a building through energy savings is supported by analysis of the DOE Weatherization Assistance Program.  Independent reports conclude that for every $1 spent to weatherize a house (up to $5000 under the current program), the occupants save $1.67 in utility costs, a savings achieved through measures such as adding insulation, air sealing, installing airtight doors and windows, and occasionally upgrading HVAC equipment and ducts.

In the new homes market, Habitat for Humanity affiliates across the country have succeeded in building affordable housing units that are up to 50% more energy efficient to operate (achieving HERS scores in the low to mid-50s), feature materials with low embodied energy, and are cost-effective, saving the families hundreds of dollars per year in operating costs. (To see case studies on high performance Habitat building, see upcoming FAS report titled “Habitat for Humanity High Performance Building Guide”.)

The US Federal Government has begun to address the need for improved energy efficiency in the building sector through legislation in areas such as:  investments in weatherization (the American Recovery and Reinvestment Act of 2009), commercial and residential energy efficiency tax credits (among others, the Energy Improvement and Extension Act of 2008), federally backed energy efficient mortgages, and setting energy use goals and standards for federal buildings (the Energy Policy Act of 2005 and Executive Order 13423 of 2009).  However, all current US energy legislation will save only a fraction of President Obama’s recently announced target of 17% energy savings by 2020.  My comparison, the European Commission has just tentatively approved an “Energy Performance of Buildings Directive,” which mandates that all new construction be “near zero energy”; this directive is estimated to have the potential to reduce the EU’s greenhouse gas emissions by 70% of their energy savings target of 20% by 2020.

In order to fulfill any promises that are made at Copenhagen over the coming days and weeks, the US will need to set an ambitious buildings energy efficiency target akin to that approved by the European Commission.  This target must be supported by both public and private action and investment, including:  government legislation, incentives, and workforce training; private sector financial investment and the development of a strong, competitive, energy efficiency market; technological innovation both from industry and the national labs; and the rapid development and deployment of high performing building energy codes and standards.

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You can meet up with friends, go shopping for high fashion clothing, browse through a fanciful New York City, and build your dream house.  You can also participate in your company’s annual conference, practice patient care in an O.R., and attend a lecture by a Harvard professor.  All in the Second Life virtual world.  And recently added to that list of activities to do in Second Life is: learn how to inspect a home built from structural insulated panels (SIPs), an advanced, energy efficient building system.

But why construct a building inspector training module in Second Life?

Both the American Clean Energy and Security Act of 2009 and in the American Recovery and Reinvestment Act of 2009 set aside billions for energy efficiency and energy savings programs and green industries.  A key aspect of these bills is the creation of “green” jobs and training workers to fill these positions, with a strong emphasis on existing home weatherization and retrofits.  After all, the building sector in the United States currently use more energy and more electricity than any other sector, and much of this energy is lost to inefficient structures with a leaky thermal envelope and poor (or no)  insulation.  Substantively reducing energy demand therefore requires a combination of constructing more energy efficient, sustainable new buildings and performing deep retrofits on existing buildings.  Doing so will save money at both the household and national levels and will decrease our nation’s carbon emissions from energy.

The federal government has appropriated money to advance the state of energy efficient housing technologies and subsidize retrofits and new construction projects.  However, neither retrofits nor new construction can take place without a well-trained workforce of architects, engineers, building professionals, tradesmen, and code officials who know how to design, built, and inspect energy efficient structures.  At present, many industry professionals have no experience with or training in how to properly utilize advanced building technologies and materials and this lack of training and experience has proven to be a huge barrier to their adoption.  And so in order to transition the building industry into a more efficient and sustainable sector, tools and programs must be rapidly developed to train industry professionals in energy efficiency theories and practical applications.

In order to train workers effectively within a short period of time, the tools must be virtually based to eliminate geographical restrictions, they must be interactive and engaging to enable learning, and they must be able to simulate scenarios and situations in the real world, promote collaboration between students and instructors, and provide the means by which to learn through problem solving and independent exploration.  And at the present time, one of the only tools available that fulfills all of these requirements is virtual world technology.

To assess the utility of virtual worlds to building industry training, the Federation of American Scientists Building Technologies Program has created a pilot training module for building inspectors that utilizes the Second Life virtual world and web-based tools.  This module educates building inspectors about how to inspect houses constructed with structural insulated panels (SIPs).  In this interactive virtual environment, building inspectors can investigate structural and architectural details, interact with animated models, click on details to obtain descriptions, CAD Images, and drawings of the detail, watch a presentation, and take a self-assessment of knowledge gained.  Through these features, users learn about the importance of energy efficiency and how to achieve a tight building envelope, constructability and code compliance issues commonly found in SIP construction, and information about SIPs themselves.

While not a fully functional pilot, initial feedback indicates that virtual worlds are indeed valuable training tools, especially when coupled with an independent web-based learning module.  By combining classroom learning with field-based learning scenarios, virtual world training improves comprehension of classroom material and shortens the in-field learning curve, thereby speeding up the training process.  And due to its web-based nature, virtual world training can allow students to be trained in areas of the country where there are few trainers or certified professionals.  As such, FAS recommends further development of virtual training modules as a solution to the need to train workers for a more energy efficient building sector.

To read the Building Technology Program’s report to Lawrence Berkeley National Lab on the training, click here.  To visit the building inspector training module in Second Life, teleport to: 142, 18, 27.

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In the ongoing efforts to reduce our nation’s carbon output by improving the energy efficiency of our built environment, a new old idea is shaping up to be a key player: cool roofs.  Used throughout the Mediterranean and tropical climates worldwide, the solar reflectance value (albedo) of a white or light-colored roof has been long understood—the more sunlight the roof reflects, the less the building absorbs and the easier it is to keep the building cool.

A recent report by Hashem Akbari, Surabi Menon and Art Rosenfeld titled, “Global Cooling: Effect of Urban Albedo on Global Temperature”, quantifies cool roofs’ potential impact on improving energy efficiency and slowing climate change.  The report notes that painting 100 feet² of black roof a lighter color offsets the extra heating caused by 1 metric ton of CO₂ in the atmosphere.  Scaled up to the national level, converting dark-colored roofs and pavements in urban areas around the world to lighter colors would offset the extra heating caused by 44 billion metric tons of CO₂in the atmosphere, effectively offsetting over 6 years of the U.S.’s CO₂ equivalent greenhouse gas output and saving the country over $1 billion per year in energy costs.

Clearly, cool roofs are a big deal.  But from a building technology perspective, just painting the roof a lighter color isn’t enough, since the lighter color only solves half of the cool roof equation.  Calculating the coolness of a roof requires measuring both solar reflectance (the fraction of solar energy reflected by the roof) and thermal emittance (the measure of a roof’s ability to radiate absorbed heat as infrared light); the most useful method available for calculating roof coolness is the solar reflective index (SRI).  This index utilizes both factors to generate a 1-100 SRI rating, where 100 indicates a roof with perfect solar reflectance and thermal emittance.  The higher the SRI, the cooler a roof will be, even in full sunlight on a hot day.

Much like the HERS index for whole house energy efficiency, this rating index is essential to meeting the goal of retrofitting and constructing new buildings with cool roofs.  Without a scientifically sound method to rate the cooling properties of various roofing materials, consumers cannot make educated decisions and the maximum cooling benefits cannot be harnessed.

And while many current cool roof materials apply the latest and most advanced technologies, from spray polyurethane foam systems to brightly-colored tiles that reflect infrared energy, our historic understanding of the relationship between color and solar reflectance retains its preeminent importance.  Lighter roofing materials keep buildings cooler than darker materials, yielding more energy efficient structures that have a lower carbon footprint and are less expensive to operate.

Resources on Cool Roofs:

Hashem Akbari, Surabi Menon and Arthur Rosenfeld, “Global Cooling: Effect of Urban Albedo on Global Temperature”, 2008.  http://repositories.cdlib.org/lbnl/LBNL-63490/

Energy Information Administration, “Emissions of Greenhouse Gases Report”, December 2008.  http://www.eia.doe.gov/oiaf/1605/ggrpt/

The Lawrence Berkeley National Laboratory (LBNL) Cool Roofing Materials Database. http://eetd.lbl.gov/coolroof/

The Cool Roof Rating Council (CRRC).  http://www.coolroofs.org/

Celeste Allen Novak and Sarah Van Mantgem, “What’s So Cool About Cool Roofs”, GreenSource, March 2009.  http://continuingeducation.construction.com/article.php?L=68&C=488&P=1

The DOE Cool Roof Calculator provides an estimate of cooling and heating savings for small to medium size facilities that purchase electricity with a demand charge and an alternative version for larger facilities. http://www.ornl.gov/sci/roofs%2Bwalls/facts/CoolCalcEnergy.htm

The EPA Cool Roof Calculator allows the designer to input specific details about a building, including heating and cooling systems as well as location and the cost of energy. http://www.roofcalc.com/RoofCalcBuildingInput.aspx

A PDF version of this document is available here.

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The FAS Building Technologies program has just released a policy analysis titled “Implementing Energy Efficiency in Building Codes Based on the American Clean Energy and Security Act of 2009″, written by FAS intern Amit Talapatra.  Link to the full PDF of the paper here.  

The purpose of this analysis is to provide better understanding of the implications of Section 201 of the American Clean Energy and Security Act of 2009, also known as the Waxman-Markey Climate Bill. This analysis examines specific provisions of the bill and investigates ways for the Department of Energy and private code-development organizations to implement these policies using existing tools and methods available to them. The topics covered here include: ways to meet new energy efficiency targets, methods for defining cost-effectiveness, procedures to assure state compliance and issues that may arise if private organizations do not meet the requirements of the bill. For each of these topics, this analysis focuses on the relevant language in the bill, determines what questions stakeholders are interested in and answers these by taking both technical and policy factors into consideration.

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The Building Technologies Program has just released a new report titled “Adaptations of Cementitious Structural Insulated Panels for Multistory Construction“.  Written for the Charles Pankow Foundation, this document explores the procedures for designing and constructing cementitious structural insulated panels (CSIPs) elements in multi-story buildings.  While the International Residential Code currently covers SIPs for buildings of two stories or less, no code has been written and very little testing has been performed on utilizing SIPs, especially CSIPs in multistory (3+stories) construction.

Both in practice and in code, SIPs are primarily targeted toward single-story, residential construction.  However, FAS believes that SIPs have strong potential to play a wider role in both the commercial and residential sectors of the building industry.  One barrier toward the adoption of this advanced technology system is the lack of available information for architects and engineers on the properties of CSIPS and on methods to adopt in applying CSIPS to multistory buildings.

This report seeks to fill that information gap by providing material, data and appendixes in such a manner and in sufficient detail that a knowledgeable engineer can replicate and apply the design and construction methods and principles described herein.  In addition, the first chapter serves as a detailed overview of history, materials, fabrication methods and current uses and markets related to SIPs in general and CSIPs in particular.

A PDF copy of the full report is available here.

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One year ago today, an earthquake struck the Sichuan Province in China. The earthquake was the 19th deadliest of all time. Early surveys indicate that over 170,000 square miles were affected at a level of “slightly damaging”, and over 1200 square miles on the level of “devastating”. As of May 7^th,, 2009, there are 68,712 dead and more than 17,923 missing. With such excessive damage, rebuilding has been required on a massive scale.

In late April of 2009, media outlets reported that families displaced by the Sichuan Earthquake housed in Temporary Housing Units (THUs) were experiencing health related problems due to the buildings. There is speculation that formaldehyde is the culprit. While FAS has no direct evidence to support or discredit this claim, the work we did on air quality in emergency housing built after Hurricane Katrina makes it possible to make some informed guesses about what is happening in China.

To this end, we’ve put together an article looking at the potential indoor air quality problems in China, with proposed solutions moving forward. The paper can be found here.

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Construction continues on FAS’s demonstration house in Houston, Texas. Trusses have been put up, and the envelope is almost finished. We’ve gotten more pictures as well, and we’re posting them on FAS’s flickr account, which can be found here.

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When it comes to solving the nation’s energy crisis utility bills hardly seem like much of a big deal.  But improving access to the information in the billing records of the nation’s gas and electric utilities could provide powerful tools to increase the efficiency of energy use in the US.  This is particularly true in residential and commercial buildings that consume 70% of US electricity and are responsible for 40% of all US greenhouse gas emissions.

Unfortunately, utility bill information is stored in a huge number of idiosyncratic formats and is not accessible to individuals and organizations that could use it.  This complex, un-standardized landscape means that anyone interested in comparing their energy use with national averages, or understanding how their building is performing in terms of energy consumption, has to do an enormous amount of work sorting through confusing bill information.  The small investment it would take to get these billing records into standardized formats, and making them easily available to anyone with permission to use them, would pay large dividends, for example by helping individual consumers make better decisions when they are purchasing and operating buildings, and by helping officials managing public programs designed to encourage building energy efficiency make better management decisions.

In the future, detailed information about patterns of consumption may make sense when there’s widespread use of “smart meters” that keep track of energy use minute by minute, and possibly appliance by appliance.  But major gains are possible simply by reporting energy use for each month.  Here are some examples:

• Legislation could require that billing records and benchmarking data be disclosed to potential buyers at time of sale.  Labels providing data on a building’s energy use have been developed in Europe and are being considered in California and other parts of the US.  Most labels being considered include both calculated energy demand (called “asset rating”) and measured energy consumption (called an “operational rating”).   The US Environmental Protection Agency has developed a tool called a portfolio manager that lets building owners compare the energy performance of their buildings with the performance of similar buildings in similar climates.  At present nothing similar is available for residential buildings. The burden on the user would be greatly reduced if billing data can be uploaded automatically, using standardized formats.
• If billing records for a building are available online with suitable permissions, a utility, or a third party like Google could provide a service where a consumer could go on line, identify themselves with an appropriate password, and get access to the building’s history of energy use by month – preferably several years of data.  This could then be automatically compared with energy use from similar structures in similar climates, and estimates of the reductions likely to result from cost-effective retrofits.  Consumers might well be motivated to take action.  Benchmarking tools for this purpose have already been developed by the Environmental Protection Agency.
• Good building energy audits involve entering data about a structure into a computer model that estimates a building’s energy use and also computes the savings that would result from different retrofit measures that could be taken (adding insulation, replacing windows, etc.)   Unfortunately these models are often wrong since the outcome depends on the skill and experience of the person using them.  Accuracy can be improved if the models include an analysis of the actual energy consumption of the structure.  Monthly consumption data, made available to building auditors by permission of the building owner, can be used to track the sources of inaccuracy in the data input and, and algorithms could be developed over time that would suggest corrections to the user.   Improved models will lead directly to retrofits that show better performance and are more cost-effective.   The cost of doing this would be greatly reduced if auditors could access consumption data directly over the internet using appropriate network security tools.  In the future most auditors are likely to be using wireless, handheld units at the building site to collect data and perform the energy use estimates.  These could also have direct access to the data.  The software for these tools would need to be adjusted for each utility if each company keeps data in a different format – at a significant increase in cost.
• Utility data available online could also be used to strengthen project management for retrofit programs.  The performance of individual auditing and contractor teams could be continuously measured and compared based on the actual impact their work had on energy use in the buildings they serviced.   The persistence of savings could be measured over a period of years and the actual performance of different approaches to retrofits compared in ways that could lead to continuous improvement of the programs.  This, of course, would require collecting and maintaining data on the kinds of measures undertaken and  the cost of the installations in a standardized format.
• Energy use data collected in a consistent form would also permit continuous analysis of progress, or lack of progress, of city, state, and national programs to improve energy efficiency.  It could be used, for example, to compare programs in different cities, and track the impact of different policy interventions in considerable detail.  While care would need to be taken to ensure that identifiable personal information is not released, statistical agencies have considerable experience in analyzing data scheduled for publication to ensure that this doesn’t happen – and they have a good track record of success.  The novelty in this new system, of course, would be that the data would be gathered online.  Careful design of network security would needed.
• The introduction of “smart grid” technology will open more opportunities for collecting detailed information about building performance.  The new systems will let building owners and utilities adjust consumption to avoid system peaks and provide information useful for understanding the consumption of specific equipment in the buildings that can, among other things, be used to understand the impact of any retrofit measures undertaken in the building — with statistically significant samples.   The smart grid will require standardized approaches to measuring and reporting consumption data.

Taken together, the benefits of a consistent national format for the energy consumption of individual utility customers would be considerable.  The benefits would include much improved management and accountability for retrofit program funds, and more energy savings per dollar invested.  While some utilities may complain about the cost of converting existing data formats to a new format, the overall costs would be small compared with the savings that could be achieved.

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