Research library
HVAC and energy statistics
Heating, cooling, home energy and indoor air data for 2026. Every number links to the group that published it and carries its date.
25research pages
3,711primary-source citations
233charts from the original sources
October 2026last updated, refreshed monthly
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HVAC energy consumption
How much energy heating and cooling use in homes and buildings, by end use, fuel and climate.
Read all 129 statistics- Space heating and air conditioning together took 52% of a U.S. household's annual energy in 2020, more than every other use combined.
- Air conditioning used 254 billion kWh in 2020, about 19% of the electricity used in U.S. homes.
- Households in very cold and cold climates used 54.0 million Btu for space heating in 2020, about 4.7 times the 11.5 million Btu used in hot-humid climates.
- ERCOT peaked at 91.1 GW on July 22, 2026, 6.5% above its previous record, in what EIA describes as the hottest U.S. summer on record.
Energy
How much energy homes and countries use, what it costs and what saves it.
- Energy consumptionHow much energy countries and households use, by sector and fuel.World energy supply passed 600 exajoules (EJ) in 2025, up 1.7% on 2024
- Energy povertyHow many households struggle to pay for energy, in the US and in Europe.43.56 million of 132.54 million US households reported at least one form of energy insecurity in 2024.
- Energy StarCertified products, savings, shipments and what the ENERGY STAR program has delivered.ENERGY STAR and its partners have helped American families and businesses avoid more than $500 billion in energy costs since 1992.
- Geothermal energyGround-source heat pump shipments, geothermal capacity, costs and payback.Indonesia now leads the world in geothermal power capacity at 2,744 MW, just ahead of the United States at 2,725 MW.
- Home energy efficiencyWhat efficiency upgrades save, who claims the tax credits and how homes score.About 24.9 million US homes were poorly insulated or not insulated at all in 2020.
- Natural gasSupply, prices, home use and emissions of natural gas, and how many homes heat with it.U.S. natural gas consumption averaged a record 92.0 billion cubic feet per day (Bcf/d) in 2025.
- PropaneHomes that use propane, how much they use, prices, supply and safety.The 2020 Residential Energy Consumption Survey counted 5.21 million US homes that use propane as their main heating fuel.
- Smart home energy savingsSavings from smart home devices other than thermostats, and how many homes use them.Lighting used 244 TWh of electricity in 2020, about 14% of all U.S. electricity use.
- Smart thermostat energy savingsWhat measured studies say smart thermostats save, and how many homes have one.Google Nest reports average savings of 12% on heating and 15% on cooling across its US studies and Seasonal Savings trials.
Heating & cooling
Heat pumps, furnaces, air conditioning, heat waves and the facts of the trade.
- Air conditioningHow many homes have air conditioning, what cooling costs and how fast demand is growing.Global electricity demand for space cooling has grown 50% since 2015, to around 2,900 TWh, more than the total electricity demand of the European Union.
- FurnaceFurnace shipments, efficiency, age and lifespan, replacement and safety.US makers shipped 4,008,894 gas warm air furnaces in 2021, the high point of the 2006 to 2025 series.
- Heat pumpSales, adoption by country, efficiency, cost and how heat pumps do in cold weather.US heat pump sales in 2025 were around 12% higher than sales of fossil fuel heating systems.
- Heat waveHow often heat waves hit, how long they last and what they do to the grid and the economy.The US summer of 2026 averaged 74.4°F, the warmest June to August in 132 years, beating the records set in 1936 and 2021 by 0.4°F.
- HeatingHow homes are heated: fuels, equipment, heating degree days and costs.Utility gas was the main heating fuel in 61,887,114 of 132,737,146 occupied U.S. homes in 2024.
- HVAC factsSourced facts and surprising numbers about heating, cooling and the people who install them.U.S. patent 808,897, "Apparatus for Treating Air," was issued to the Buffalo Forge Company on January 2, 1906, with Willis Carrier's drawing filed alongside it.
Health & safety
Mold, carbon monoxide, heat deaths, indoor air and space heater fires.
- Carbon monoxide poisoningPoisonings, deaths and ER visits from carbon monoxide, and which appliances cause them.An estimated 274 people died from CO tied to consumer products in 2022, more than in any year since the coding change of 1999.
- Heat related deathsDeaths and illness from heat, who is most at risk and why air conditioning matters.The US reported 2,391 heat-related deaths in 2024.
- Indoor air qualityIndoor pollutants, time spent indoors, health effects and what filters and fresh air do.Americans spend about 90 percent of their time indoors, where some pollutant levels are often 2 to 5 times higher than outdoors.
- MoldHow common mold is, what it does to health and what damp homes cost to fix.Dampness affects 10 to 50% of indoor environments in Europe, North America, Australia, India and Japan.
- Space heaterFires, injuries and running cost of space heaters, and who relies on them.Space heaters and heating stoves caused 30% of home heating fires in the U.S. but 73% of the deaths.
Buildings
Replacement, insulation, retrofits and green buildings.
- Building electrification retrofitRetrofit costs, gas rules, building emissions and what electric heat does to the grid.Homes and businesses caused 31% of U.S. greenhouse gas emissions in 2022 when electricity use is counted.
- Green buildingGreen certifications, market share, cost premiums and the value of efficient buildings.Buildings are responsible for 39% of global energy related carbon emissions: 28% from operations and 11% from materials and construction.
- InsulationR-values, how many homes are under-insulated and what insulation saves.About 26.8 million US homes, one in five, were poorly insulated or not insulated at all in 2024.
- Residential HVAC replacementHow old systems get, what a replacement costs and when owners repair instead of replace.Central air conditioner and air-source heat pump shipments fell 20.0 percent in 2025, to 7,749,529 units from 9,681,770 in 2024 ().
Method
How these pages are sourced
- 01
Primary sources only
Each number comes from the agency, lab or research team that produced it. Pages that repeat other people's data are not cited.
- 02
Every link opened
We load each source and confirm the number and its date on the page before the stat goes in. Stats that fail are dropped.
- 03
Updated monthly
We check the sources every month and replace old figures. The updated date moves only when the content changes.
HVAC Load
Size the job from the real load
HVAC Load works out the heating and cooling load, the tons and the duct sizes on your iPhone.