Since 2006, the U.S. Environmental Protection Agency (EPA) has operated WaterSense® in partnership with manufacturers, utilities, and consumer groups. Similar to EPA's ENERGY STAR® role for energy-efficient products, WaterSense® employs a labeling system to identify water-efficient products, homes, and services. As of 2015, the WaterSense® program can claim credit for a total savings of 1.5 trillion gallons of water and $32.6 billion in consumer water and energy bills. Savings are tracked in the National Water Savings (NWS) model that combines innovative analyses with methodologies established in the energy sector. Merging life-cycle cost and national impact analysis models, the NWS model estimates savings from a bottom-up accounting method for individual products. The model extends those savings to the national level by employing parameters such as frequency of product use by number of people and building type, product lifetime, stock accounting, and market saturation. The NWS model tracks the water and consumer monetary savings of WaterSense-labeled products for residential and commercial water use both indoors and out.

This paper presents estimates of the key impacts of Federal energy and water conservation standards adopted from 1987 through 2012. The standards for consumer products and commercial and industrial equipment include those set by legislation as well as standards adopted by DOE through rulemaking. In 2012, the standards saved an estimated 3.6 quads of primary energy, which is equivalent to 3% of total U.S. energy consumption. The savings in operating costs for households and businesses totaled $51.4 billion. The average household saved $347 in operating costs as a result of residential and plumbing product standards. The estimated reduction in CO2 emissions associated with the standards in 2012 was 198 million metric tons, which is equivalent to 3% of total U.S. CO2 emissions. The estimated cumulative energy savings over the period 1990-2070 amount to 179 quads. Accounting for the increased upfront costs of more-efficient products and the operating cost (energy and water) savings over the products’ lifetime, the standards have a past and projected cumulative net present value (NPV) of consumer benefit of between $1,104 billion and $1,390 billion, using 7 percent and 3 percent discount rates, respectively. The water conservation standards, together with energy conservation standards that also save water, reduced water use by 1.8 trillion gallons in 2012, and will achieve cumulative water savings by 2040 of 54 trillion gallons. The estimated consumer savings in 2012 from reduced water use amounted to $13 billon.

Lawrence Berkeley National Laboratory (LBNL) has developed a mathematical model to quantify the water and monetary savings attributable to the United States Environmental Protection Agency’s (EPA’s) WaterSense labeling program for commercial and institutional products. The National Water Savings–Commercial/Institutional (NWS-CI) model is a spreadsheet tool with which the EPA can evaluate the success of its program for encouraging buyers in the commercial and institutional (CI) sectors to purchase more water-efficient products. WaterSense has begun by focusing on three water-using products commonly used in the CI sectors: flushometer valve toilets, urinals, and pre-rinse spray valves. To estimate the savings attributable to WaterSense for each of the three products, LBNL applies an accounting method to national product shipments and lifetimes to estimate the shipments of each product.

New single-family home construction represents a significant and important market for the introduction of energy-efficient gas-fired space heating and water-heating equipment. In the new construction market, the choice of furnace and water-heater type is primarily driven by first cost considerations and the availability of power vent and condensing water heaters. Few analysis have been performed to assess the economic impacts of the different combinations of space and water-heating equipment. Thus, equipment is often installed without taking into consideration the potential economic and energy savings of installing space and water-heating equipment combinations. In this study, we use a life-cycle cost analysis that accounts for uncertainty and variability of the analysis inputs to assess the economic benefits of gas furnace and water-heater design combinations. This study accounts not only for the equipment cost but also for the cost of installing, maintaining, repairing, and operating the equipment over its lifetime. Overall, this study, which is focused on US single-family new construction households that install gas furnaces and storage water heaters, finds that installing a condensing or power-vent water heater together with condensing furnace is the most cost-effective option for the majority of these houses. Furthermore, the findings suggest that the new construction residential market could be a target market for the large-scale introduction of a combination of condensing or power-vent water heaters with condensing furnaces.

In 2001, the U.S. Department of Energy (DOE) initiated a rulemaking process to consider whether to amend the existing energy efficiency standards for furnaces and boilers. A key factor in DOE's consideration of new standards is the economic impacts on consumers of possible revisions to energy-efficiency standards. Determining cost-effectiveness requires an appropriate comparison of the additional first cost of energy efficiency design options with the savings in operating costs. DOE's preferred approach involves comparing the total life-cycle cost (LCC) of owning and operating a more efficient appliance with the LCC for a baseline design. This study describes the method used to conduct the LCC analysis and presents the estimated change in LCC associated with more energy-efficient equipment. The results indicate that efficiency improvement relative to the baseline design can reduce the LCC in each of the product classes considered.

In 1975 the U.S. federal government established its role in improving appliance and lighting energy efficiency by setting voluntary labeling and efficiency guidelines for residential appliances and lighting products under the Energy Policy and Conservation Act (EPCA, P.L. 94-163). In 1987 EPCA and subsequent legislation was amended and updated by the National Appliance Energy Conservation Act (NAECA, P.L. 100-12). NAECA superceded requirements established by some individual states and set the first national energy efficiency standards for home appliances. A schedule for regular updates, currently specified to 2012, was also established. NAECA standards now influence appliances and equipment comprising about 80% of the source energy in the U.S. residential sector.