Summers are famously humid in upstate New York, but life at Maioli's home has become more comfortable since the couple installed a new heating and air-conditioning system, one that is still not widely known in the US. USA
“My wife is very happy because in the summer we can keep it as cold as we want,” usually 69 or 70 F, said Joe Maioli, in Ontario, New York. In 2021, the couple installed a ground source or geothermal heat pump.
The units you see that look like box fans outside of homes and businesses are the most common air source heat pumps. They squeeze energy from outside air to generate heat and absorb excess heat inside and push it out when they cool. Geothermal heat pumps use underground temperatures, instead of outside air.
There is now a big push for people to consider ground source heat pumps because they use much less electricity than other methods of heating and cooling. “Ground-source heat pumps consume 30 percent less electricity on average than air-source heat pumps over the course of the heating season,” said Michael Waite, senior manager of the American Council for Buildings program. an Energy Efficient Economy.
“Cooling the house for a month costs maybe $10 in electricity, and this is the most efficient way to do it,” Maioli said. During the coldest winter month, her highest heating bill was around $70, she said.
To install ground fountain systems, contractors bring in heavy equipment and drill to bury a loop of coiled tubing several hundred feet deep in your yard. The water that flows through the circuit takes advantage of the underground temperature, a fairly stable 55 F.
Inside, often in the basement, a unit contains refrigerant, a liquid that can easily absorb a large amount of heat. In summer, the water in the circuit sheds heat on the ground. In winter, it extracts heat from the ground with astonishing efficiency and brings it indoors.
“We really feel like we're on the right side of a megatrend,” said Tim Litton, director of marketing communications for WaterFurnace, a geothermal manufacturer in Fort Wayne, Indiana.
With most popular air-source heat pumps, Litton said, the exterior parts can freeze in winter. The system then has to draw heat from inside to defrost them. There is also dirt, animals and debris.
The WaterFurnace systems can be placed in patios as small as 15 by 15 feet, he said. But drilling rigs can't go where houses are close together.
There is “a lot of demand for geothermal right now,” said Mark Schultz, president of Earth River Geothermal in Maryland, and the interest in reducing carbon emissions is a big motivator for customers. “They have electric vehicles at the driveway and solar panels on the roof,” he said of the sites he is bidding on.
In the Midwest, Litton sees a wide range of buyers. “We run across the political spectrum, whether you're a progressive environmentalist or a fiscal conservative,” she said. “It's good in these divisive times to have something to agree on,” she said.
The sticker prices for the ground source are higher than traditional systems. But in a stamp of approval for their efficiency, last year's Inflation Reduction Act gives them a big incentive, with a 30% tax credit. So a customer buying a $30,000 system would end up paying $21,000. If someone doesn't owe enough tax in one year to benefit from that, they can carry it over to the next year. There is also no dollar limit on the credit, unlike air source units, which are capped at $2,000.
Some states are offering credits on top of that. In South Carolina, residents get another 25% credit, which means a homeowner could end up with 55% off the initial cost. Some utility companies also offer incentives. South Carolina customers who have the Blue Ridge Electric Co-op as their utility can get up to $1,600 per ton for the system they install. A 5-ton heat pump installed in a 2,000-square-foot home, for example, would recoup $8,000 from the utility.
People who live in places with cold winters and hot summers get the most savings. Still, the leaders of three interviewed companies mentioned the initial cost as a barrier.
Corey Roberts lives on Long Island, New York, and installed a geothermal system made by Dandelion Energy last July. I was renovating and needed a new heater and air conditioner. He was also interested in sustainability. He chose Dandelion after comparing costs with a natural gas system.
“I can tell you that the house is cooler than ever and the heating is the most constant we've had since we've lived here. We are very happy,” Roberts said.
The initial cost was $63,500, much more than the $27,000 natural gas option. But after the 30% federal tax credit plus a $5,000 state tax credit for geothermal energy plus a rebate from his power company, it was about $32,000.
“Dandelion was only a $5,000 difference from a conventional system. If you think about how long it takes to recoup costs in savings, it's pretty fast,” Roberts said.
The new system has attracted interest from friends and neighbors.
“We have a lot of people on the street asking us how it works and we say it's like magic. The water moves around a pipe in the ground and voilà, here we are heating and cooling. It's amazing,” she said.
Born out of a Google innovation lab in 2017, Dandelion designs, installs, and maintains its own systems in New York, Connecticut, and Massachusetts. CEO Michael Sachse said the inspiration for the company was to find an affordable way to control the temperature in the home without contributing to climate change.
“There are three main ways that people can reduce their carbon emissions: change what you drive, how much you fly, and how you heat and cool your home,” Sachse said. "Particularly if you're in a place where the winters are cold, the way you heat your home will have a huge impact."
Dandelion is currently working on a partnership with Lennar Corp, one of the largest homebuilders in the country, and thinks that in the future, new homes will be built with geothermal instead of natural gas. He said that Dandelion is currently identifying a community "where we can work on 100 or 200 homes at a time."
Litton also sees growth for the WaterFurnace. Residential geothermal heat pumps currently make up just 1% of the US heating and cooling market but make up 20% of the European market, due to a long history of higher fossil fuel prices and more incentives.
In addition to the cost and disruption to the yard, there can be permitting delays, in part because some jurisdictions are not accustomed to geothermal.
Another challenge is invisibility.
“You probably went through several geothermal facilities today and you don't even know it because it's all underground,” Litton said.