Direct Use Geothermal Energy

What is Direct Geothermal Energy?

[br]Geothermal energy has been in use for more than two thousand years. However, till recently, the scale of application of this source of energy has been limited. Geothermal energy is harnessed more for direct use than as a source of electricity.Geothermal energy, in simple parlance, refers to energy that is derived from the earth’s heat. Broadly speaking, the earth is divided into three layers: the core, the mantle and the crust. The innermost part of the earth is the core, while the most of the earth is made up of the mantle. The mantle reaches temperatures of over 1000 degrees Celsius and the topmost layer of the mantle is made up of sizzling magma. The outermost layer of the earth, the crust, is very thin. At places, the magma manages to break through the thin crust, causing volcanoes. At other places, hot water can escape through the crack in the earth’s crust to form hot springs and geysers.

History of Geothermal Direct Energy

Geothermal heating has been in use for centuries. Ruins of ancient civilization have been unearthed on the Japanese archipelago and many of these sites are located near present day hot springs. In China, written records of geothermal usage dating back a couple of thousand of years have been found. The ancient Roman civilization also used geothermal energy for heating buildings and spas.

[br]Geothermal energy was not harnessed on a large scale until the beginning of the twentieth century. While Italy made progress with converting geothermal energy into electricity in the early 1900s, Iceland was the first to use this source of energy for a large scale heating service in the 1930s. The application of geothermal energy can broadly be classified into two categories, namely direct use and geothermal electricity. Under the first category, geothermal energy has a wide variety of uses, including space heating and cooling, greenhouses, heat pumps, fish farming and supply of hot water to facilities like spas and swimming pools. Within this category, space heating is the leading application of geothermal energy.

Uses of Direct Geothermal Energy

The direct utilization of geothermal energy is more popular across the globe than the use of geothermal electricity. As compared to geothermal electricity, the direct use of geothermal energy supports higher energy efficiency and involves lower investments of initial capital. Moreover, the development time is shorter in the case of the direct use of geothermal electricity.