The History of HVAC and Energy Efficiency

30% Complete

"So how did all this start? And why are there these large and bright yellow energy star efficiency stickers all over the appliances in my house?"



Heating and cooling equipment utilize a lot of energy in order to operate, in fact, when compared to all the other appliances and products in your home that consume energy, heating and cooling equipment make up the majority of a utility bill at around 48% according to the Energy Information Administration.

What was once considered a luxury, the HVAC system is now an essential part of every home, business, hospital, laboratory, data center, resturaunt, grocerie store, and has influenced almost every modern structure & industry in some way. It's true, without HVAC so many of the modern inventions or advancements in technologies that we use in our everyday lives simply wouldn't be if the HVAC field was never invented, and at this point it's hard to imagine what life would be like today without HVAC's influence.

It's also true that without HVAC, advancements in areas such as health and medicine, food, transportation, entertainment, and technologies such as the internet and printing silicon chips that make up processors in computers and cell phones simply wouldn't be where they are today, or exist at all.







1902 - The Beginning or Air Conditioning

Willis Carrier The coolest inventor in the world (no pun intended) Willis Carrier invented the first modern electrical air conditioning unit while working at the Buffalo Forge Company in 1902. Mr.Carrier was an engineer tasked with solving a humidity problem that was causing magazine pages to wrinkle at the Sackett-Wilhelms Lithography and Publishing company in Brooklyn, and in 1902 through a series of experiments, Mr.Carrier designed the first electrical air conditioning system, which he dubbed his "Apparatus for Treating Air". From there the invention took off, exploding into the standard it has become today, with an air conditioning system located in an estimated 87% of all US households.

Today, the Carrier Corporation is still very alive and one of largest manufacturers of HVAC equipment in the world, and you may have even noticed the Carrier name on your own HVAC equipment, or perhaps your neighbors.



The 1970's - War, Oil, The Energy Crisis, and the D.O.E

The US Department of Energy Seal During the 1970s air conditioning use soared, most new homes were being constructed with central air conditioning systems, yet unfortunately it is during this time period that oil production began to decline as the United States entered the energy crisis of 1973 which had sparked as a result of the Yom Kippur War in Israel on October 6th, 1973.

You may have heard stories of this moment in time - President Richard Nixon was in office, and efforts to reduce oil consumption led to a national maximum speed limit of 55 mph imposed via the Emergency Highway Energy Conservation Act.

And, even gasoline purchases were being regulated and the ability for drivers to fill up their gas tanks at gas stations was governed by odd-even rationing, which meant people were only allowed to fill their gas tanks on certain days of the week depending the last digit on their vehicle's license plate - If the last digit was an odd number, then drivers could get gas on an odd day of the month, and even numbered license plates could only fill up on even days of the month.

It is during this time that more than 2 million barrels of oil were being used per day rather than created, and it is during this time we see the nation begin to desperately focus on energy conservation methods in hopes of conserving oil.

With pressure stemming from the first oil crisis of the 1973 and the stock market crash of 1973-1974, President Ford enacts the Energy Policy and Conservation Act of 1975 (EPCA), which established a federal program consisting of test procedures, and energy targets for consumer vehicles and appliances, with the focus being on vehicles and oil conservation. It is during this time that the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) develops the efficiency standards we still use today for HVAC equipment, including the EER, SEER, HSPF, and AFUE, which are defined in the EPCA.

However, the EPCA's suggested "energy targets" for appliances are just that - Suggested and voluntary energy targets, as at this point no entity or legislation exists to enforce these suggested energy targets, and they are simply established in text books and on legal documents as definitions.

In 1977 President Jimmy Carter decides to consolidate several of the leading energy comissions in a single indentity in hopes of developing a solution to the nations energy problem, and organizations such as: The Federal Energy Administration, The Energy Research and Development Administration, The Federal Power Comission, and dozens of other energy conservation organizations are combined into a sole identity as Jimmy Carter signs into the law, The Department of Energy Organization Act, and on October 1, 1977 the US Department of Energy is born.

The DOEOA of 1977 not only establishes the DOE as an entity, but declares that The Department of Energy is to be responsible for enforcing regulations in everything from the US Navy nuclear weapons program and nuclear reactor research and production regulations, to energy conservation and energy related research in deomestic energy production.



1978-1979 - Regulating Indoor Temperature

A Locked Thermostat In 1978 the National Energy Policy and Conservation Act (NEPCA) was passed by congress and signed by President Carter. This act (NEPCA) focused on vehicle and appliance energy efficiency once again, and this time, specifically directed the DOE to begin establishing and enforcing energy conservation standards for household appliances and charged the FTC (Federal Trade Commision) with issuing appliance energy efficiency labeling rules.

A year passes and as appliance standards are being debated in the political arena the result is nothing but failure, and none of the major and needed solutions President Carter was looking to gain out of the DOEOA are coming together. No major changes are officially enforced or seen in the HVAC field until June 20th, 1979 when we see the first regulations of indoor temperature in the United States - Enacted as an emergency conservation effort through the Carter Administration as the United States enters the next major oil shock crisis of 1979, President Carter proclaims a national energy supply shortage and establishes temperature restrictions in non-residential buildings (with some exceptions, such as Hospitals and other temperature sensitive industries) in efforts to conserve oil. Through this emergency act, all non-residential building temperatures (with regards to the industry exceptions) are to be maintained no lower than 78 degrees during the summer, and no higher than 65 degrees during the winter.

Although this regulation didn't apply to American households, the Carter Administration was asking all Americans to voluntarily raise their home thermostats during summer and lower them during the winter in efforts to combat the oil supply shortage. The Energy Department had estimated that 200,000 to 400,000 barrels of oil a day would be saved through the combined efforts of these temperature restrictions, and the Department of Energy was assigned to task this enforcement with fines of $5,000 to $10,000 a day to non-residential structures that didn't comply.

This is a notable time in history because it's the first time we see the nation reacting to energy conservation through an emergency act that regulated HVAC operation.



1987-1992 - Regulating Minimum Efficiency Standards

A 10 SEER Heat Pump Carters regulations on controlling indoor building temperature actually lasted from 1979 until 1981, when President Ronald Reagan came into office. The Reagan administration greatly opposed controlling building temperatures or setting appliance standards required by the NEPCA of 1978 and proposed a "No-Standard" standard, and then proposed shutting down the DOE completely, which ultimately resulted in nothing.

The Reagan-Led DOE had come to a crawling stand still when it came to enforcing or researching the topics legally outlined by the NEPCA by embracing a "No-Standard" Standard. Since the DOE had failed to abide by the NEPCA, states began to try and regulate energy efficiency in household appliances in their own way, making it very difficult for manufacturers to mass produce products that could be sold from state to state - This "red tape" formed from states trying to mandate and regulate their own efficiency laws led to many manufacturers coming together and sueing the DOE for failing to come up with a solution which the NEPCA of 1978 had legally instructed them to do. This suit ended up turning into a long legal battle that lead to little progress in terms of HVAC efficiency until the late 1980s after the suit was over and a Court of appeals ruled against the DOE and the Reagan Administration.

It wasn't until 1987, after the DOE was sued, that we finally start to see the enforcement of appliance efficiency standards on the federal level, which the DOE was tasked to establish and enforce so many years ago with the NEPCA of 1978 under the Carter Administration. Finally, after over a decade since the first Energy Policy and Conservation Act of 1975 when efficiency ratings were established and energy targets were suggested, it was time enforce a minimum efficiency rating that all manufacturers of HVAC equipment had to meet as they produced HVAC equipment off the assembly line, and in 1987 Congress declared The National Appliance Energy Conservation Act (NAECA) that set the minimum efficiency standards for 12 appliances, including central air conditioning systems, heat pumps and furnaces, and scheduled these minimum efficiency standards to go in effect between 1990-1993 depending on residency type and equipment type. The table below shows the minimum efficiency ratings declared in 1987:



Minimum US Federal Efficiency Standards Enacted by NAECA of 1987

Equipment Type Minimum Efficiency Effective Date
Residential Central Air Conditioners (Split Systems) 10 SEER 1/1/1992
Residential Heat Pumps (Split Systems) 10 SEER / 6.8 HSPF 1/1/1992
Residential Central Air Conditioners (Packaged Systems) 9.7 SEER 1/1/1993
Residential Heat Pumps (Packaged Systems) 9.7 SEER / 6.6 HSPF 1/1/1993
Residential Furnaces 78% AFUE 1/1/1992
Mobile Home Furnaces 75% AFUE 9/1/1990

6 years later in 1993 we finally see the complete enforcement of the NAECA of 1987 come into full swing across the nation and within the field of HVAC, 18 years after the first Energy Policy and Conservation Act of 1975. It is at this point that we begin to see the big yellow Energy Star/Energy Guide labels (see below) begin to emerge on appliances clearly stating and comparing the efficiency standards and savings the product provides.

Regulating minimum energy efficiency ratings at which air conditioning and heating equipment had to meet was a great solution to everything the nation had been through, including President Carter's desparate emergency building temperature control program, and allowed regulations to extend into every structure in America - Both residential and non-residential, including the medical industry as well as every other industry exempt from Carter's emergency building temperature control program. From now on, no matter what industry you were operating under, if you bought a new air conditioner, heat pump, or furnace on or after 1993, it had to meet up to the minium efficiency levels defined by the NAECA.



2000-2006 - Raising Minimum Efficiency Standards

An energy star sticker rated at 13 SEER The year 2000 was the next big milestone for HVAC efficiency. After 6 years of analysis, the Clinton Administration proposed and approved raising the current minimum SEER rating from a SEER rating of 10, to a SEER rating to 13 across the board for all air conditioning and heat pump equipment, however, the deadline for HVAC manufacturers to meet this new standard was declared to come into effect in 2006, which was outside of President Clinton's term. As President Clinton's term came to an end in January of 2001, the newly appointed Bush Administration came into office and proposed to cut more than $200 million from federal renewable energy and efficiency research programs, and only a single month after coming into office the Bush Administration proposed to lower the 13 SEER minimum standard approved by the Clinton Administration down to a minimum of 12 SEER, which would reduce HVAC energy efficiency by 13% if enacted.

Debates and legal battles went on for years concerning exactly what to do next with HVAC efficiency (13 SEER vs 12 SEER, Clinton Administration vs Bush Administration), but in the end, the originally proposed minimum SEER rating elevation standard of 13 SEER by the Clinton Administration was enacted during President Bush's term in 2006, with notable and supporting arguments made by the EPA (Environmental Protection Agency) and the ASE (Alliance to Save Energy) stating that it is in fact illegal according to the National Appliance Energy Conservation Act (NAECA) of 1987 to enact a new standard that would reduce or roll back an energy efficiency standard which had already been previously established - The nation had already gone through this episode before with President Reagan and established laws so it could never happen again.

Once again, the minimum SEER efficiency rating you could achieve when you purchased new central air conditioning / heat pump equipment was changed, and this time the bar was raised to 13 SEER across the entire United States. Once again, no matter where you were located or what industry you were apart of in the US, if you bought a new air conditioner or heat pump the minimum SEER efficiency level you could purchase was rated at a minimum of 13 SEER, however, no ammendments to furnace AFUE efficiency ratings were made at this time.

The energy savings from this one act alone increased the energy efficiency of air conditioners and heat pumps by 30%, and eliminated the need to build as many as 140 more electrical power plants by the year 2020.



2015-Today - Efficiency Standards Based on Location

From 2006-2011 efficiency standards remained the same at a minimum of 13 SEER for air conditioners and 78% AFUE for furnaces, but it was at this point the Department of Energy began to really focus on optimizing efficiency standards and noticed that HVAC equipment varies depending on where one is located. Some parts of the US had more HVAC equipment than others, some areas made more use of heating equipment and some areas made more use of cooling equipment. Energy savings and consumption also varied depending on ones location due to the way HVAC equipment was operated. A new approach to energy efficiency and conservation was needed, one that would focus on the individual differences of climate and usage across the nation - It was time to start optimizing efficiency levels based on location and once again re-write the rules in a more efficient manner that capitalized on various gaps formed from the differences in climate per region of the United States.

This regional approach to energy efficiency all started around 2011 when the DOE began to revise their HVAC energy conservation rules from a "one-size-fits-all" approach to the current regional approach that began to take into consideration the climate differences across the US. The older "one-size-fits-all" approach to energy efficiency simply couldn't apply to the HVAC energy conservation any longer, and in April of 2014 the DOE confirmed that as of Jan 1, 2015, efficiency standards were going to vary depending on the region of the United States the HVAC equipment was located within and the United States was split into 3 regions, including: the North, the South, and the Southwest, each with it's own HVAC efficiency standards as listed below:


Department of Energy HVAC Efficiency Zones

Northern Region States Southern Region States Southwestern Region States
Alaska New York Alabama Arizona
Colorado North Dakota Arkansas California
Connecticut Ohio District of Columbia Nevada
Idaho Oregon Delaware New Mexico
Illinois Pennsylvania Flordia
Indiana Rhode Island Georgia
Iowa South Dakota Hawaii
Kansas Utah Kentucky
Maine Vermont Louisiana
Massachusetts Washington Maryland
Michigan West Virginia Mississippi
Minnesota Wisconsin North Carolina
Missouri Wyoming Oklahoma
Montana South Carolina
Nebraska Tennessee
New Hampshire Texas
New Jersey Virginia


Zones Split A/C Packaged A/C Split Heat Pumps Packaged Heat Pumps Gas Furnaces (Weatherized) Gas Furnaces (Non-Weatherized) Oil Furnaces (Non-Weatherized)
North 13 SEER 14 SEER 14 SEER
8.2 HSPF
14 SEER
8 HSPF
14 SEER
81% AFUE
90% AFUE 83% AFUE
Southern 14 SEER 14 SEER 14 SEER
8.2 HSPF
14 SEER
8 HSPF
14 SEER
81% AFUE
80% AFUE 83% AFUE
Southwestern 14 SEER / 12.2 EER < 45,000 BTU/H

14 SEER / 11.7 EER ≥ 45,000 BTU/H
14 SEER / 11 EER 14 SEER
8.2 HSPF
14 SEER
8 HSPF
14 SEER
81% AFUE
80% AFUE 83% AFUE



"Alright.. Well, thanks for the history lesson, but what do all these efficiency ratings actually mean? And, how do they apply to my own HVAC equipment?"

Right! So, now that we know the history and todays current standards, let's go ahead and discuss what these efficiency ratings actually mean, and what types of HVAC equipment they apply to.