As Tahoe temps rise, especially the overnight lows, residents are turning to air conditioning to cool off.

Barbara and Gary Cooper recently had Nixon Heating and Air Conditioning of South Lake Tahoe install their unit.

“The problem seems to be night temps are warmer and we can’t leave windows open at ground level because of animals,” said Barbara Cooper, who lives in the unincorporated area of El Dorado County. “When it is really warm we wake up and it is 60 outside.”

Another reason the couple installed the forced air unit is to combat smoky days when it’s impossible to open windows for natural ventilation.

It’s been in the last few years that the heat has started to be an issue for Becky and Roy Darrow who have lived in their Zephyr Cove home for 47 years.

“We put in a whole house fan last year and then followed up with air conditioning this year,” Becky Darrow said. “The fan works great once the sun goes down and the outside air cools down. But since our house gets full-on sun in the afternoons the fan doesn’t help at that time of day.”

The Darrows also own two office buildings in Zephyr Cove, which have had some type of cooling mechanism—air conditioners and evaporative coolers—for a number of years to contend with tenants using multiple computers and servers that create heat and need to be in a cool environment.

Tilley Plumbing & Heating of Stateline is seeing an increase in the number of Tahoe residents wanting air conditioning, like at this home on Lower Kingsbury Grade having a unit installed by Connor Wasilewski. (Photo: Aden Pillsbury)

Thermometer readings

The National Weather Service in Reno reports the high temperatures in South Lake Tahoe in 2020, 2021, 2022, 2023 and 2024 are in the top 10 for highest maximum temps, with all being more than 90 degrees.

The mercury is read at Lake Tahoe Airport.

The highs were: 91 degrees in 2020, 93 in 2021, 92 in 2022, 93 in 2023, and 92 in 2024.

July is the hottest month of late, though it can be August.

The average normal highs and lows for South Lake Tahoe in June are 72 and 38 degrees, 80.4 and 42.5 in July, and 79.7 and 41 in August.

The highest overnight temp recorded at the airport was 62 degrees, which occurred in 1988 and 1970. The overnight lows are highest in June-July-August.

In 2015, 2021 and 2023 the highest overnight temp was 60 degrees, 55 in 2020, 58 in 2022, 57 in 2024, and as of mid-August 48 degrees for 2025.

Looking at the numbers 

Anderson Heating & A/C of Carson City, the company the Darrows used, has seen a definite uptick in the number of A/C units being installed in the basin.

Rafael Hernandez, an estimator with the company, said they’ve installed about 30 air conditioners in Tahoe in the last two summers. That’s the same number Tilley Plumbing & Heating of Stateline has put in.

Both companies only work in Nevada. No HVAC company in South Lake Tahoe returned calls.

On older homes a concern is whether the existing duct and electrical systems can handle an A/C unit without upgrades because air conditioning requires more duct flow than heating.

“Since we were able to use our existing duct work the air isn’t as effective as it could be. But adding new ducts would have made the project more invasive and more expensive,” Darrow said.

Hernandez said another issue is homeowners’ associations can have rules about where the apparatus can go and how much noise it will make.

Nick Tilley, owner of the Stateline HVAC company, said people new to the area are more likely to add A/C; people who are accustomed to forced air and not opening windows at night.

This could be why real estate agents are also seeing an increase in the number of clients who want air conditioning already installed.

“People are asking about A/C when looking at homes now. Fifteen years ago A/C was a non-issue, but with climate change, and hotter temps there is an interest in A/C,” Ginger Nicolay-Davis, a broker associate with Compass Real Estate in South Lake Tahoe, said. “I think we will continue to see the demand for A/C to rise.”

Some homes she has sold had mini splits as a cooling option, which allows for a single room to be cooled instead of the entire house.

Mike Phillips with Realty World in South Lake Tahoe is seeing bigger new builds coming with A/C, while it’s mostly out-of-towners requesting it.

Houses on the market on the California side with A/C had a median price of $996,000 compared to the overall median of $726,000, according to Phillips.

It’s not just Tahoe witnessing a spike in A/C units. According the Energy Information Administration, in 2001 77 percent of U.S. households had air conditioning, while in 2020 88 percent did.

Based on how jurisdictions’ permitting systems are set up officials say it’s difficult to provide exact numbers for A/C installs.

South Lake Tahoe officials estimate of the 155 new single family permits issued in the last five years between 80 and 90 had air conditioners, while five commercial builds did. Another 20 units are likely to have been part of remodels.

“Of the 8,780 permits from 2024, filtered for permits in SLT, there are 90 for mechanical, which A/C-HVAC fall under, both residential and commercial. Of those, eight appeared to be new A/C units,” Carla Hass, EDC spokesperson, said.

Douglas County provided an assessor’s map with numbers, showing a handful of A/C or mini splits being installed at the lake since 2020.

What others say 

Despite the increase in cooling systems in the basin, neither Liberty Utilities nor NV Energy have seen a surge in electrical use. This could be because the temperatures in the basin don’t require daily use of the units, unlike places like Carson City, Reno and Placerville.

“Our engineers reviewed summertime electric load demand over the last four years. They found that although there were occasional daily spikes, potentially caused by excessive heat and the need for cooling units, the overall trend was essentially flat. These results were consistent in both North and South Lake Tahoe,” Kurt Althof, Liberty’s regional communications manager, said.

A program expert at NV Energy said, “According to U.S. Energy Information Association, A/C accounts for 9 percent of home energy use across all U.S. households, but in cooler climates like Tahoe that number is likely lower and may not be more than about 5 percent.”

NV Energy said no one on the South Shore has participated in its A/C tune-up or replacement programs from 2022 until now.

Air conditioning is not tied to any Tahoe Regional Planning Agency threshold or permit.

“The Climate Action Plan looks at the winter heat efficiency of homes and other buildings in the region as use of natural gas relates to the greenhouse gas emission inventory for the basin,” spokesperson Jeff Cowen said. “A/C uses electric power, which is produced outside the region. Climate change could continue to impact the communities and environment of the Tahoe basin and in new ways.”

TRPA’s building in Stateline had A/C when the agency purchased it.

The League to Save Lake Tahoe “encourages people to use the minimal and most energy efficient smart heating and cooling systems available, as well as incorporating passive design principles, in new construction and renovations.”

Communications Director Chris Joseph also said the nonprofit advocacy group as done this at its new office. Insulation is made from recycled denim to reduce the number of days forced air—hot or cold—is needed.

Note: A version of this story first appeared in the Tahoe Mountain News.