Geothermal energy deals with harnessing the warmth of the earth's core. One of the applications of geothermal energy is heating water.
There are two types of geothermal water heating systems. One system is designed to be used in combination with a radiant water heating system. Another popular design utilizes a geothermal heat pump to heat the water. Of the two, geothermal pump heating systems are growing popular, as they are a more affordable solution as compared to radiant geothermal heating systems. The US government is promoting the use of geothermal water heating. Under the 2005 energy bill, an owner of a ground source heat system can earn up to 300$ in tax credits.
A basic geothermal closed loop system consists of thick high-strength plastic pipes buried in the ground. These pipes are filled with water or antifreeze solution. These plastic pipes are placed in a looped manner. Loops may be horizontal ranging from 100 feet to 500 feet in length or vertical loops that are 100 to 300 feet deep.
The alternative to a closed loop system is an open loop system. Here, running water from a water source such as a well is circulated through pipes. These pipes play a crucial role in taking heat from the ground and transferring it to warm the air and water in your house during winter. Geothermal energy heats water by using a system that re-uses lost heat.
Part of the heat that is generated in a closed loop heating system is used to heat water. Up to 35% of your homes’ hot water requirements can be supplied by geothermal energy. It should be noted that geothermal heat pumps are very efficient. They are said to be five times more efficient than a gas furnace in terms of fuel conversion. Geothermal energy can be used to heat water to up to 105 degrees Fahrenheit. This means that geothermal water heating is usually supplemented with a traditional form of water heating.
The advantage of harnessing geothermal energy for water heating is that it is free, clean, and renewable. Geothermal water heating systems are ideal due to their low consumption of energy and low maintenance costs. Desuperheaters are devices that harness geothermal energy for on-demand tankless water heaters. This device utilizes excess heat in summer that is wasted by being expelled into the ground. This device, however, is not as effective in winter and will need to be supplemented by a storage water heater. Around 70% of the energy used in a geothermal heat pump water heating system is renewable. The consistent warmth of the earth's core is what makes this possible.