Frequently Asked Questions
Geothermal Energy and Its Advantages
A geothermal system is a device that utilizes heat from the ground to heat or cool a building. It consists of three main elements:
- An underground heat exchanger, which captures heat from the ground at a certain depth where the temperature is relatively constant (around 9°C in Quebec).
- A heat pump or geothermal heat pump, which concentrates the heat captured by the exchanger and transfers it to the building in heating mode or reverses the process and releases the building's heat to the ground in cooling mode.
- A heat distribution system, which circulates warm or cool air in the building, such as air ducts or radiators.
There are different types of geothermal systems based on depth, temperature, and heat exchange mode with the ground. For example, closed-loop systems circulate a heat transfer fluid in a sealed circuit, while open-loop systems pump and reinject groundwater directly. Systems can also be classified based on orientation (horizontal or vertical) or heat source (shallow or deep).
Geothermal energy offers numerous advantages over conventional heating and cooling systems, which typically rely on fossil fuels or electricity. Some of these advantages include:
- Geothermal is a renewable energy source that doesn't burn fossil fuels and produces no greenhouse gases, contributing to the fight against climate change.
- It is a clean energy source with minimal waste and pollution, avoiding the risks of radioactive leaks or nuclear waste associated with nuclear energy.
- Geothermal is an efficient energy source, utilizing the constant heat from the subsurface to reduce energy consumption and heating/cooling costs by approximately 70%.
- It is a readily available thermal energy source that can be harnessed in any geographical location, independent of weather conditions or day-night cycles, unlike solar or wind energy.
- Geothermal provides stable energy production, unaffected by fuel price fluctuations or the availability of fossil fuels.
Geothermal is therefore a green and cost-effective energy option with environmental and economic benefits compared to conventional heating and cooling systems.
As geothermal energy is a renewable source using Earth's heat for building heating and cooling, it offers various environmental benefits, such as:
- It doesn't burn fossil fuels, reducing greenhouse gas emissions and air pollution.
- It produces minimal waste, which is either reinjected into the ground or appropriately treated.
- It poses no risks of radioactive leaks or nuclear waste, unlike nuclear energy.
- It relies on abundant and sustainable natural resources unaffected by fuel price fluctuations.
- It provides constant and reliable energy, regardless of weather conditions or day-night cycles.
Geothermal is, therefore, a clean and green energy source contributing to the fight against climate change and environmental preservation
Geothermal energy offers various economic benefits, including:
- Significant return on investment.
- Substantial government subsidies to reduce geothermal costs.
- Low maintenance costs.
- Long equipment lifespan (25 years for heat pumps and 75 years for wells).
- Potential reduction in insurance costs.
- Increased property value.
The lifespan of a geothermal system depends on its main components, namely the heat pump, the underground circuit, and the distribution system. Estimates include:
- Geothermal heat pumps last around 25 years if installed by a qualified professional and regularly maintained, surpassing the average lifespan of traditional outdoor heat pumps (13 to 15 years).
- The underground circuit can operate smoothly for over 75 years, requiring minimal maintenance.
- The distribution system's lifespan depends on the existing heating type in the house, whether it's forced air, hot water, or electric baseboards. The lifespan varies based on the type and quality of materials used.
Geothermal is, therefore, an ingenious and efficient energy solution with a long lifespan and low energy consumption.
No. A geothermal heat pump is always at least two (2) times more efficient than an air-to-air heat pump (traditional outdoor heat pump). In very cold temperatures, geothermal efficiency drops to 200%, while outdoor air-to-air heat pumps fall to 100% efficiency (from -5 degrees, -12 degrees for the most efficient ones).
Yes, you can combine a geothermal system with other energy sources based on your existing heating system and energy needs. Examples include:
- Combining geothermal with electric forced-air or hot water heating, where geothermal handles most heating and cooling, and electric heating serves as a backup when needed.
- Combining geothermal with wood or pellet heating, where geothermal provides cooling and part of the heating, and wood or pellet heating adds warmth and a renewable energy source.
- Combining geothermal with solar thermal or photovoltaic panels, where geothermal covers heating and cooling, and solar panels provide hot water or electricity.
Geothermal systems are relatively low maintenance, but regular checks are recommended to ensure efficiency.
Yes, it is entirely possible to install a geothermal system in an existing residence. This is known as a geothermal retrofit, becoming increasingly common as homeowners seek to reduce their carbon footprint and energy costs.
Geothermal can be adapted to most regions, but a feasibility assessment is essential. Factors such as soil type, groundwater presence, available space, and your home's energy needs determine the geothermal system options.
Yes, geothermal is suitable for both small and large homes, providing comfort and efficiency regardless of size.
No. We install deep vertical loops and can work in confined spaces. Permanent column wells can serve a very large building with just one well.
Installing a geothermal system in an existing residence can take between 3 and 5 days, depending on factors such as soil type, system type, house size, system size and complexity, site conditions, geothermal loop type, and equipment availability. It involves drilling, landscaping, piping, and distribution system adjustments or installations.
To find out more, visit the Hydro Québec-website: Geothermal systems.
Here are some of the main components and equipment commonly used in geothermal systems:
- Geothermal sensors: Geothermal sensors, such as pipe loops, are buried in the ground to extract geothermal heat. There are different types of sensors, including horizontal sensors (buried horizontally), vertical sensors (drilled deep), and groundwater sensors.
- Geothermal heat pump: The geothermal heat pump is the heart of the system. It uses heat extracted from the ground to heat a fluid, usually a refrigerant, which is then compressed to increase its temperature. The produced heat is transferred into the building to heat it.
- Heat exchanger: A heat exchanger is used to transfer heat between the geothermal fluid and the building's heating or cooling system. It can be a coil of pipes inside a water tank or an air-to-water heat exchanger.
- Distribution system: The heating or cooling distribution system can vary depending on the application. It can be air ducts for distributing heat in a forced-air heating system, radiant floor heating for radiant heating, or hot water radiators.
- Control system: A control system is used to monitor and regulate the operation of the geothermal heat pump and the distribution system. It helps maintain a comfortable temperature in the building while maximizing energy efficiency.
This involves drilling holes in the ground, 3 to 6 inches in diameter and a depth ranging from 150 to 600 feet on average. A looped pipe is inserted to allow the circulation of a non-toxic heat transfer fluid (which transfers heat) connected to the geothermal heat pump in your basement.
Geothermal works can potentially disturb the terrain, but they are designed to minimize damage and leave the site in an acceptable condition after installation. The impact on the terrain largely depends on the method of installing geothermal loops, the system's size, and site characteristics.
The initial installation costs of a geothermal system depend on several factors, such as house size, soil type, chosen system type, and drilling depth. Multiple government incentives are in place in Québec to make geothermal energy accessible to a larger audience.
The time needed to recover the initial investment in a geothermal system depends on various factors, such as system cost, energy savings achieved, available financial assistance, the type of heating replaced, and energy costs. There is no one-size-fits-all answer, but the average payback period for geothermal systems in Québec is estimated to be a few years to a decade. This period may be shorter if the system replaces oil or propane heating, or longer if it replaces electric heating. It's also essential to consider that the lifespan of a geothermal system exceeds that of a conventional system, increasing long-term profitability. Geothermal is, therefore, a profitable investment that requires a long-term perspective.
Numerous provincial and federal government incentives are in place to make geothermal energy more affordable for residents of Québec. These include LogisVert, Chauffez vert, the RénoVert tax credit, the ÉcoPerformance program, the RénoClimat program, and Maisons Plus Vertes.
LogisVert is an assistance program established by Hydro-Québec to encourage homeowners to carry out energy improvement work in their homes. The LogisVert program will provide grants for the purchase and installation of energy-efficient equipment and appliances, such as heat pumps, heat storage units, solar thermal sensors, induction stoves, heat pump dryers, etc. The LogisVert program will be launched in the summer of 2023 and will replace existing grant programs. Eligible renovations carried out since January 2023 will be eligible for LogisVert program grants. For more information, please visit: https://www.hydroquebec.com/residential/energy-wise/financial-assistance/logisvert.html.
Contact us directly to discuss your needs, schedule an evaluation, and obtain personalized information about geothermal energy for your project.
Additional information is available at the following sites:Hydro-Québec and Canadian GeoExchange Coalition (CGC).
Vous avez d’autres questions ou préoccupations? N’hésitez pas à communiquer avec nous ou à consulter nos pages relatives à notre modèle d’affaires ou à la géothermie.