From solar, wind, and geothermal energy to bioelectricity, hydropower, and energy storage, renewable energy technologies are a recurring topic on our blog. As you may know, renewable energy is derived from natural sources that we are not likely to run out of. These replenishable power sources include wind, moving water, heat from the earth, sunlight, ocean waves, and even organic waste.
Even though renewable energy is often thought of as a new technology, we have been leveraging Mother Nature’s power for heating, lighting, transportation, and more for a long time. Geothermal energy, in particular, has been harnessed by humans for years to perform household purposes like cooking and heating. Recently, advanced technology has allowed us to utilize geothermal electricity more effectively and its popularity has slowly gained traction in various regions around the world.
In the United States, we use and produce a mix of different energy sources. In 2017, renewable energy accounted for 12.7% of primary energy production, and in 2019, the consumption of produced renewable energy grew for a fourth year in the United States, reaching 11% of total U.S. energy consumption. Geothermal energy is a key renewable energy source throughout the world, especially for the United States, which holds the highest worldwide installed geothermal capacity at 3.8 GW.
However, electricity isn’t the only way we can use geothermal. As mentioned previously, before using it to generate electricity, humans used geothermal for direct heat, bathing, cooking, and heating buildings. While geothermal direct heat is still used today in production, agriculture, and for buildings, only a diminutive portion of its potential has been unlocked.
Geothermal heating and cooling systems, referred to as Ground Source Heat Pumps (GSHP), provide heating and cooling by exchanging heat with the ground. These systems take advantage of the temperature of the ground remaining relatively constant throughout the year, ranging from 45o to 75oF.
There are a handful of options to consider when it comes to selecting a GSHP system. One consideration is choosing from closed- or open-loop designs. A large part of GSHPs in the U.S. use ground heat exchangers to circulate fluid through a closed-loop design. In a closed-loop design, pipes are usually made from plastic tubing and are buried either horizontally or vertically. However, the design of a ground heat exchange system can vary significantly based on certain factors, such as soil conditions, the climate, land availability, and accessibility to water (whether it be groundwater or surface water).
On average, heating accounts for roughly 35-50% of annual energy bills in the colder states of the country, being the single largest energy expenditure in most American households. We spend $73 billion each year on space heating alone! Similarly, home air conditioning costs homeowners over $29 billion annually and accounts for just about 6% of all electricity produced in the U.S. Combined, home heating and cooling contribute to roughly 441 million tons of carbon dioxide each year, not accounting for how heating and cooling residential and commercial buildings contribute about 11% of total carbon dioxide emissions in the U.S.
Luckily, consumers today have a lot of choices when it comes to heating and cooling systems. One viable and sustainable option may be right below their feet. Home geothermal systems create zero carbon emissions and use resources below the Earth to help use 75% less energy than traditional heating and cooling systems. As such, utilizing geothermal to heat your home is one of the easiest ways to reduce your eco-footprint. If you’re curious about other ways to minimize your impact on the environment, remember to stay tuned to the Kiwi Energy blog.