The Advantages of a Closed Loop Geothermal System

Emily Fazio
·4 min read

You're considering geothermal energy for your home? So lucky. Geothermal heating and cooling is a great way to lean into sustainable energy, and a long-term cost-effective solution that'll benefit your home and family and increase property value. Whether you adopt a vertical system or a horizontal configuration, geothermal energy systems harness the Earth's natural heat to promote energy savings and reduce your carbon footprint.

With minimal environmental impact and consistent performance regardless of weather conditions, geothermal technology ensures reliable comfort year-round. Plus, government incentives and rebates may offset installation costs, making it an even more attractive investment. All that said,

What Are Closed Loop Geothermal Systems?

"Closed loop geothermal (CLG) systems are geothermal systems that don’t exchange water with the external environment, but instead run water through a 'closed loop,' or a 'closed circuit,'" explains Kathy Hannun, Founder & President, Dandelion Energy. "The system’s underground pipes are charged with water during installation, and then sealed so that the same water circulates through those underground loops indefinitely."

Comparatively, What are Open Loop Systems?

Open loop systems refer to another type of geothermal system where water is pumped out of the ground, run, through the geothermal heat pump, and then dumped back into a nearby body of water (like a pond) or approved drainage ditch.

Advantages of a Closed Loop Geothermal System

  • Fewer maintenance requirements. They require minimal maintenance because there are fewer components exposed to external elements.

  • Reduced levels of debris and risk of contamination. The systems are lower maintenance than open loop systems because groundwater can contain debris or mineral content that can clog or contaminate the indoor heat pump.

  • Less affected by fluctuations in the groundwater levels. The systems simply aren't as vulnerable to changes in groundwater levels or flows.

  • Flexibility in installation. These systems can be installed in a variety of locations, including areas where access to groundwater is limited or the groundwater source is poor. This flexibility can make them a more practical option for a wider range of applications.

  • Higher efficiency ratings. Closed loop systems are often more efficient because they are less susceptible to fluctuations in groundwater temperature and other external factors. This can result in lower energy consumption and higher overall performance.

  • Longer lifespan. The piping system is typically buried underground, protecting it from exposure to the elements and minimizing wear and tear. As a result, closed-loop systems often have a longer lifespan than open-loop systems, providing more reliable heating and cooling over time.

Related: Can a Geothermal System Really Heat and Cool a Home? Plus, How to Calculate Cost Savings

How to Choose Between an Open- and Closed-Loop System

Not sure what's going to work best for your property? When choosing between a closed-loop or open-loop geothermal system, consider factors such as access to groundwater, environmental impact, space availability, long-term costs, climate suitability, and regulatory requirements to ensure the most suitable and sustainable option for your home.

Access to Groundwater

  • If you have access to an ample supply of clean groundwater through a well or nearby water source, an open-loop system may be feasible.

  • If access to groundwater is limited or if water quality is poor, a closed-loop system is likely a better option.

Environmental Considerations

  • If you're concerned about water conservation and minimizing environmental impact, a closed-loop system is generally more sustainable as it doesn't require continuous water usage.

  • If you live in an area where groundwater resources are scarce or where water usage is regulated, a closed-loop system may be the only viable choice.

Related: What Are Vampire Devices?

Soil Composition and Space Availability

  • Closed-loop systems require sufficient space for burying the piping system underground. If space for a horizontal system is limited, vertical loops that run 100-400 feet deep may be your only option to make the most of your footprint. If you have limited space or soil conditions that aren't suitable for burying pipes, an open-loop system might be more practical.

  • Conversely, if you have ample space and suitable soil conditions, a closed-loop system can be installed effectively.

Energy Efficiency and Long-Term Costs

  • Closed-loop systems often have more additional costs due to installation requirements, but they typically offer better long-term energy costs and lower maintenance costs.

  • Open-loop systems may have lower initial costs but can be less energy-efficient and may incur higher maintenance expenses over time, particularly if water quality issues arise.

Climate and Heating/Cooling Needs

  • Closed-loop systems can provide consistent heating and cooling regardless of external weather conditions, making them suitable for various climates.

  • Open-loop systems do not handle extreme temperature fluctuations as well; they work better with a consistent temperature.

Regulatory and Permitting Considerations

  • Check local regulations and permitting requirements regarding the installation and operation of geothermal systems, as these may influence your choice between closed-loop and open-loop options.