Go Green… Go Geothermal

As the seasons change and winter approaches, it’s time to reevaluate the heating system you use in your home. Energy costs tend to increase in the winter, but with geothermal heating systems, you can save your money and the environment.

What are Geothermal Heat Pumps?

Throughout the year, we experience many variations of temperature — from highs well above 100 degrees Fahrenheit to below zero chills– but geothermal heating takes advantage of the almost constant temperature that the earth remains only a few feet below its surface. Geothermal pumps “exchange” temperatures between your home and the earth below it. This heats your home during the winter and cools it in the summer. This is because the ground temperature is warmer than the atmosphere’s air in the winter and cooler in the summer. A ground heat exchanger is then responsible for absorbing excess heat in a home during the summer and acting as a heat source in colder months.

Closed-Loop Systems

There are many different types of geothermal heating pump systems. The climate, soil type, and area of land on your property are important conditions to take into consideration when selecting the right pump for your home. Most systems are referred to as closed-loop systems. They work by circulating water or sometimes a water-glycol solution through a closed loop. This loop is usually made with some type of plastic tubing that is embedded in the ground or submerged in water. Heat is then transferred between a refrigerant in the pump and an antifreeze solution in the closed-loop system – this process is made possible by a heat exchanger. An example of a closed-loop system is a horizontal system, which requires pipes to be installed in trenches that are only four to six feet deep. This is a cost-effective option most commonly used for new construction residential installations where a sufficient area of land is available. There are also vertical systems, which consist of pipes connected underground in holes that are 100–400 feet deep, minimizing land disturbance. These systems are often used for large commercial buildings and schools, however, they can also be used for properties where the soil is too shallow for trenching. Pond/lake systems exchange heat using water. This is only possible if the body of water meets a minimum requirement for volume and depth. If these requirements are met, a pipe can be run underground from the building to the water.

Geothermal is Getting Trendy

While geothermal pumps have been in use for decades now, the United States is just catching on to the trend. Geothermal has been adopted by much of Asia and areas of Europe too. In Norway, for example, sixty percent of buildings utilize geothermal. In recent years, geothermal heat pump sales have skyrocketed. In Europe alone, there was a thirty-seven percent increase in sales of pumps from 2021 to 2022. In the United States, heat pump sales are now surpassing gas furnace sales for the first time in decades.

Benefits of Geothermal

Cost-Effective

Although the installation price of a geothermal system can be quite unappealing to the average homeowner, the additional costs when compared to installing the common air-source system can be returned in energy savings in only five to ten years. Geothermal heating systems are estimated to have a lifetime of twenty-four years for their inside components and over fifty years for their ground loops. Further, geothermal heat pumps move heat rather than relying on combustion, which gas furnaces or water heaters do. This means they can reduce energy costs by fifty percent. The Inflation Reduction Act (IRA) has also created tax credits, grants, and rebates (partial refunds) that drive down upfront costs substantially. With the IRA, household geothermal project costs can be cut by up to fifty percent, saving as much as $15,000 for higher-cost installations. The IRA can help commercial buildings reduce upfront costs by thirty to fifty percent.

Network Systems can Improve Communities

Geothermal heating systems are especially effective in network systems that, through shared piping, can connect multiple buildings. They use energy from the ground, wastewater, ponds, and other sources. Network systems can achieve more than five hundred percent efficiency. This means that for every unit of energy that goes into the system, five times that amount is produced. Furthermore, these larger systems require infrastructure that can create local jobs and bring energy costs down for all residents.

Climate Conscious

Geothermal heating systems produce zero direct emissions, although when taking into consideration how their materials are produced, they do not have a net-zero release of emissions. In a study where appliance emissions across three Midwest utility territories were compared, it was discovered that geothermal heat pumps produce significantly fewer emissions. They produce about eighty-five percent fewer emissions than a gas furnace and ninety percent fewer emissions than a propane furnace.

Recap

Geothermal heating pumps “exchange” temperatures between a building and the earth below it. This creates a system that heats a home during the winter and cools it in the summer. The majority of systems are closed-loop, in which a solution is circulated through a piping system. Horizontal, vertical, and pond/lake systems are all variations of the closed-loop system that can be used depending on the climate, soil type, and area of land on a property. While other parts of the world have used geothermal for decades, the United States has only caught on recently, with sales of geothermal pumps outgrowing those of gas furnaces. This is because the benefits of geothermal are now finally being recognized. Geothermal is cost-effective and can reduce energy costs by fifty percent. Larger networks of geothermal can also supply a community with jobs and lower energy costs for residents in a community. Finally, geothermal does not directly emit any pollutants to the environment. Overall, geothermal is a great way to preserve the climate and a worthy investment for homeowners who are looking to save on energy costs in the long run.

References

Energy Saver

Clean Energy 101