Geothermal heating in Spain

Geothermal heating in Spain is becoming more widespread. The climate lends itself to Geothermal heating amazingly well and with the advance in technology. Geothermal heating in Spain is now a very viable solution.

How Geothermal Works

Your own backyard has the potential to be an energy source for heating and cooling systems. Outdoor air temperatures fluctuate throughout the year with the changing seasons. In contrast, ground temperatures about four to six feet below the Earth's surface remain relatively moderate and constant all year. That's because the Earth absorbs 47% of all the heat energy that reaches it's surface from the sun. A geothermal system circulates a water-based solution through a buried loop system to take advantage of these constant temperatures.

A single piece of equipment has the ability to heat and cool your home, while providing some or all of your home's hot water as well. Geothermal systems can save you 30% to 70% on your monthly utility bills and heat your pool.

Heating Cycle

During the heating cycle, the fluid circulates through the loop extracting heat from the ground. The heat energy is transferred to the geothermal unit. The unit compresses the extracted heat to a high temperature and delivers it to your home through a normal duct system or radiant heat system.

Cooling Cycle

For cooling, the process is simply reversed. Because the earth is much cooler than the air temperatures on a hot day, the geothermal system removes heat from the home and deposits it into the ground. The fluid is cooled by the ground temperatures and returned to the unit for cooling your home.

Geothermal Heating in Spain Systems

"Mining" the Earth for Heat
Home owners usually rely on two familiar systems to heat homes or buildings: fuel-powered furnaces or boilers (which burn gas, oil, or propane) and electric-powered air-source heat pumps or baseboard radiant heat. However, these traditional systems present two drawbacks. First, even highly efficient models pollute the environment because fuel must be burned to produce heat. Second, energy prices are rising. Accordingly, people want cost-effective long-term heating and cooling options. Geothermal systems are one such option: they are being installed in homes, businesses, and schools across the country.

What is a "geothermal" system? It takes advantage of the Earth’s ability to store vast amounts of heat in the soil ("geo" means earth and "thermal" refers to heat). This heat energy is maintained at a constant temperature (50°F to 70°F depending on latitude) in the soil and near-surface rocks. Spain is absolutely ideal for this system.

Geothermal heating systems, also called ground-source heat pumps, "capture" this steady supply of heat energy and "move" it from the Earth and through a home or building. Basically, once installed, a home or building owner will use much less energy, save money each month, and reduce the amount of pollution produced by fossil fuel systems. Geothermal systems represent a proven option. In addition, they utilize a renewable energy source—the Earth’s naturally-occuring heat energy.

What’s Wrong With Good, Old-Fashioned Combustion?

traditional heating systems rely on combustion (the burning of fuel) either on site or at the power plant. Fuel-powered heating units, such as gas and boiler systems, burn fuel at the site to produce heat energy. Electric-powered heating and cooling systems do not require combustion at the site of the furnace; instead, it occurs at power plants. In 1998, approximately 80% of U.S. electricity was produced by burning fossil fuels. Only nuclear, wind, and hydroelectric plants do not burn fossil fuels.

The problem with combustion systems is that the by-products they produce contain harmful emissions. These emissions degrade air quality and contribute to other environmental problems including acid rain and the greenhouse effect. For the health of individuals and communities throughout the world, it makes sense to develop heating and cooling technologies that reduce or eliminate fossil fuel combustion.

How Ground Source Heat Pumps Work

Typical ground-source heat pumps transfer heat using a network of tubes, called "closed loops." Basically, the loops are filled with either water, refrigerant or an anti-freeze solution. They run through the ground in the vicinity of a building and the liquid absorbs the Earth’s heat energy. Then, this warmed liquid is pumped back through the system into the building. This process provides heat to the building space. Once the fluid passes through the building and transfers its energy, it flows through the loop system back to the Earth and the process repeats itself.

In the summertime, these systems "reverse" into cooling mode. Technically, the system does not "run backwards." Instead, a series of valves enables the system to switch the "hot" side and the "cold" side. The heat from the building is transferred to the liquid in the loop and this liquid is pumped back into the ground. When the ground source heat pump is in cooling mode, it usually has an excess of warmed liquid in the system. This liquid can heat water for the building and basically eliminate the use of the hot water heater during the summer months.

Saving Energy

Ground-source heat pumps can use 25%-70% less electricity than conventional electric heating and cooling systems. First, in winter heating mode, a ground-source heat pump uses energy from the Earth to provide heat, whereas air-source heat pump try to extract the last bits of heat energy out of cold winter air. Because of the long, cold Wisconsin winters, air-source heat pumps are not effective or efficient.

Second, ground-source heat pumps are more energy efficient than conventional electric heaters because they maximize the thermodynamic advantage of a heat transfer fluid. This benefit enables the ground source heat pump to produce more heat energy output than electric energy input. Conventional electric heaters on the other hand don’t quite produce as much heat output as electric input. (Under some conditions, a ground source heat pump cannot meet the required heating needs. In these cases, supplemental heat must be provided from another source–usually conventional electric units.)

Third, during the summer, the ground source heat pump "reverses" into cooling mode. This fact makes the ground-source heat pump more energy efficient for cooling than a traditional air conditioner.

Finally, when a desuperheater is installed, energy from the ground source heat pump can be transferred to the hot water tank. As a result, building occupants receive "free" hot water in the summer and very low-cost hot water in the winter.

Most of a ground-source heat pump’s electrical energy requirement (70% to 80%) is consumed by the compressor and pump that combine to move heat energy to or from the ground, through the loop system, and into or out of a building. The remaining 20% to 30% of the electricity is used for fan(s) and controls to distribute the conditioned air throughout the building.

Saving Money

Since these systems use from 25% to 50% less energy than conventional systems, users will spend less on their monthly energy bills. In fact, many homeowners could spend from 35€ to 70€ less per month, meaning that most ground source systems will "pay for themselves" in 2 to 10 years.

Ground-source heat pumps can be retrofitted in existing homes that have traditional forced-air systems. In most cases, the heat pump can be connected to the existing ductwork while the loop system is installed outside in the ground adjacent to the home. [Back]