Solar power makes it easy to clean up all your electrical appliances. But what about the fossil-fueled heating and hot water systems in many of our homes?
Good news: You have plenty of options to replace the emissions-heavy heating systems in your home with an environmentally friendly alternative—and might even save you a bunch of money, too.
When most people talk about heat pumps, they're talking about air-source heat pumps. These electric all-in-one heating and cooling (and sometimes hot water) systems work by extracting heat from the air and moving it around. It works just like a regular air conditioner—except it can also run backward to warm up your home rather than cooling it off. Heat pumps have been around for decades, but they've made huge strides in the past 10 years and can now work efficiently even in cold climates.
There's some disagreement on the proper name for the technology, but whether you call them ground source heat pumps or geothermal heat pumps, they tap into the earth's stable temperature to provide heating and cooling for buildings.
These systems circulate fluid through underground pipes—hundreds of feet worth, even for a modest single-family home. The fluid absorbs heat from the ground in winter and releases heat sucked up from your home in summer. Geothermal heat pumps are highly efficient, environmentally friendly, and can drastically reduce energy consumption compared to traditional heating systems and even air source heat pumps.
The cost of installation is very high, and some properties just can't fit a geothermal system. But huge incentives are often available, and they're so energy efficient that they can offset the high upfront costs in less than a decade through savings on your energy bills.
Solar water heating systems utilize the sun's energy to heat water for domestic use. These systems consist of solar panels (collectors) installed on rooftops or in sunny areas. The collectors absorb sunlight and transfer the heat to water stored in a tank. Solar water heaters are highly sustainable, reduce carbon emissions, and can provide a significant portion of a household's hot water needs.
Tankless water heating, also known as on-demand or instant water heating, is an energy-efficient technology that provides hot water without the need for a storage tank.
Instead of constantly heating a large volume of water, tankless systems heat water only when needed. As a result, users receive a continuous hot water supply, eliminating the wait time associated with traditional water heaters and reducing water and energy wastage.
Another critical advantage is higher energy efficiency, as it eliminates standby heat losses. The energy savings over time can be substantial.
The cost of installation tends to be steeper than tank/storage water heaters, and you'll likely need multiple tankless units in your house if you need to use more than two water fixtures at a time (including showers, sinks, washing machines, and dishwashers).
Tankless systems are often powered by natural gas—not entirely clean but a smaller environmental impact than tank-style gas water heaters. Electric tankless water heaters are also available.
Heat pump water heaters work similarly to air source heat pumps but are specifically designed for providing hot water. They extract heat from the surrounding air and transfer it to the water in the storage tank. This all-electric tech cuts energy use by about 60% compared to a typical electric-resistance water heater.
As a side-effect, the most popular heat pump water heaters also cool and dehumidify the spaces where they're installed. This is a nice upside in a humid basement during the summer but it can make that space uncomfortable in the winter when it's already cold and dry. (Some models also have loud compressors, which can be annoying.) Many models are "hybrid" systems that can sidestep this problem by switching to a straight electric-resistance water heating mode—also useful if you need to refill the tank with hot water faster than the heat pump setting can manage.