In 2010, a group of HVAC and water-heating equipment manufacturers and energy and environmental advocates, with the encouragement of the U.S. Department of Energy (DOE) and Senate Energy and Natural Resources committee, reached a consensus on energy efficiency that included the development of regional efficiency standards for heating, cooling and water-heating equipment. While this hasn’t yet become law, major portions of the consensus are being implemented through a DOE rulemaking process. The resulting DOE standard starts to go into effect in May, 2013 for non-weatherized furnaces, and in January, 2015 for weatherized furnaces, air conditioners, and heat pumps.
With energy efficiency standards looming on the horizon, and more legislation on the table, it’s increasingly important for the entire HVAC industry to begin evaluating and exploring technologies which help ease the transition, and subsequent air-conditioning and heat pump equipment upgrades.
Defining the Standards
The regional efficiency standards divide the U.S. into three regions: South, Southwest, and North.
In the South and Southwest, the standards establish a minimum cooling efficiency requirement of 14 SEER for central air conditioners. Heating efficiency minimums increase only slightly, to 80% AFUE. The region includes states with fewer than 5,000 heating degree days (HDD), a population-weight calculation based on outside air temperatures and the heating requirements of a building.
The South includes states south of the Mason-Dixon line, such as Maryland, the District of Columbia, Delaware, Virginia, North Carolina, South Carolina, Tennessee, Kentucky, Alabama, Arkansas, Mississippi, Georgia, Louisiana, Florida, Oklahoma, Texas, and Hawaii. The Southwest region includes California, Nevada, New Mexico, and Arizona.
The North region (more than 5,000 HDD), includes states from Alaska and Washington, down to Kansas and Missouri, and back up the eastern seaboard from Pennsylvania and New Jersey to Maine. Here, a minimum AFUE of 90% or more for non-weatherized gas furnaces will go into effect. Cooling efficiency minimums remain unchanged at 13 SEER.
Nationwide efficiency standards will also be implemented for heat pumps and oil furnaces.
Today’s Technologies: Tomorrow’s Efficiencies
With traditional single speed compressors, increasing SEER or HSPF ratings requires the cooling or heating equipment to have more heat exchanger coil surface area and the ability to handle higher evaporator temperatures — meaning a larger cabinet and more refrigerant. This adds cost to the efficiency upgrade, especially when today’s systems can already be quite large and costly.
A compressor using variable speed technology significantly reduces energy use by constantly matching the output required to maintain a homeowner’s set point with little or no cycling on and off. In fact, adding variable speed technology to a new residential air-conditioning system can produce an increase of 4 to 5 SEER points compared to a traditional fixed-speed system. Adding variable speed compressors to dedicated outdoor air systems can result in 20 to 40% savings, depending on the local climate.
When variable speed drive (VSD) compressors are paired with microchannel heat exchangers (MCHE), manufacturers are able to increase efficiency without increasing equipment size, and achieve an overall 30% SEER improvement. Microchannel heat exchangers can reduce system footprint by 40%, don’t require the addition of more refrigerant to the system, and help to lower evaporator temperatures.
In humid climates like the Southeast and North, a VSD compressor and MCHE solution in air-conditioning systems provides maximum moisture removal. In the dry Southwest, systems benefit from the technologies’ higher cooling efficiency. All homeowners, regardless of region, benefit from the optimal indoor comfort, thanks to a VSD compressor’s ability to regulate indoor temperatures to a minimum variation of +/- 0.3 F, and noise reduction that a variable speed air-conditioning system would provide.
In the north, VSD compressors and micro channel heat exchangers reduce the need for back-up resistance heat by boosting heat pump capacity and increasing HSPF by 15% and higher.
Beyond the Standards
These technologies do more than help meet the DOE’s regional efficiency standards and any forthcoming legislation. They are also smart grid-ready, which is of increasing focus, especially in areas such as California. Variable speed air-conditioning systems offer:
- improved load control capabilities during utilities’ peak days while minimizing the impact on a home’s comfort
- increased air-conditioning equipment efficiency as the system is unloaded on these peak days
- adapting the load to momentary transient conditions on the utility grid, which reduces the need for costly reserve generation capacities
- variable speed compressors offer improved power factors compared to traditional fixed-speed systems, which reduce transformer load and power grid losses.
Turning Standards into Law
In April 2011, the Senate Energy and Natural Resources committee introduced, with strong bi-partisan support, the consensus agreements as S.398 or Implementation of National Consensus Appliance Agreements Act (INCAAA).
S.398 also includes other provisions, including legislation that would enable states to incrementally raise equipment efficiency standards — above basic equipment standards — for new construction through building energy codes, as well as some revisions to products.
Today, given the current stalled political environment, S.398 hasn’t yet passed the Senate; however, the bill could advance U.S. building energy efficiency policy while avoiding a controversial regulatory rulemaking process.
- The bill recognizes the climate differences that exist in three major U.S. regions, and proposes appropriate equipment standards for each. This helps to avert the implementation of individual state and local standards, which would be difficult and costly for the industry to meet.
- The bill also acknowledges that newer, highly efficient equipment can more easily be installed into new building construction where space and power venting (for condensing furnaces and water heaters) can be made available, and where mortgage financing makes the higher, up-front cost more affordable. Conversely, in the replacement equipment market, installation space can be constrained and mortgage financing isn’t often available, making the replacement of old equipment with new high efficiency equipment more costly up front.
Once enacted, it’s estimated that INCAAA would save 1.2 quadrillion BTUH of energy annually by 2030, and save consumers more than $50 billion in energy costs, according to the American Council for an Energy-Efficiency Economy (ACEEE). This is in addition to reducing brownouts and blackouts and environmental benefits like reducing carbon dioxide (CO2) emissions.
Despite bipartisan political support, the bill doesn’t carry the endorsement of the entire HVAC industry. Organizations such as Air Conditioning Contractors of America (ACCA) and Heating, Air-conditioning & Refrigeration Distributors International (HARDI) have opposed the standards, citing relevant concerns for the industry, specifically contractors and distributors, such as:
- Consumers’ reluctance over initial costs of higher efficiency equipment
- The ability of the DOE to effectively enforce the standards, including the possibility it would create excessive paperwork for small business owners who do successfully comply
- Cost undercutting of bids by contractors who choose to operate against the standards
- Product stocking issues that could result for equipment distributors with cross-regional coverage, as well as unused, uninstalled inventory that can’t be installed under the new standards.
An organization of natural gas companies has also filed suit against the DOE with the attempt to block the implementation of requirements for higher efficiency condensing gas furnaces in the north.
It’s difficult to argue against the concept of energy efficiency. It reduces the country’s dependence on foreign oil sources and, therefore, improves national security. It reduces the industry’s environmental impact, minimizes the need for the construction of additional power plants to accommodate the nation’s growing energy demand and, ultimately, saves homeowners money on utility bills. As a country, we’ve come a long way in how we value energy. And, as an industry we’ve made vast improvements in the efficiency of equipment. However, energy requirements continue to grow, so we must continue to deploy technologies that will offset those energy needs. It’s important that the industry work together to collaborate on an approach that makes sense, and that avoids the piece-meal approach that would result if each state and locality specifies its own efficiency regulations.
Dan Schillinger is business development manager, variable speed equipment, for Danfoss. Robert Wilkins is Danfoss’ vice president, public affairs.For the ACCA viewpoint on Regional Efficiency Standards, visit bit.ly/accaregionalstandardsCB
For the HARDI viewpoint on Regional Efficiency Standards, visit bit.ly/hardiregionalstandardsCB