Geothermal Energy

GEOTHERMAL ENERGY

RENEWABLE & ALTERNATIVE
ENERGY SOURCES

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Photo by Viktor Hava

Introduction

Geothermal energy provides the opportunity to produce large amounts of clean, secure and sustainable electricity and heat for residential and industrial buildings as well as for district heating systems 24/7. By using geothermal systems, we can reduce greenhouse gas emission not only in urban areas but also globally.

Description

Basically, geothermal energy is heat that is generated within the Earth. This type of renewable energy source is available only in certain location, but usually in abundance. In order to be able to use this heat, we need a transfer medium which is usually water. Depending on the temperature of this medium, we can produce energy for heating buildings, electricity or use it in thermal baths.

Cities with appropriate underground reservoirs of steam or hot water can exploit this special renewable energy source efficiently and reduce their energy dependency. Geographical conditions, the existing databases and know-how can guarantee a high level of utilisation of this alternative energy source.

Geothermal energy has a great potential in reducing greenhouse gas emissions while contributing to the realisation of the energy objectives set at EU-level. Therefore, higher utilisation of geothermal energy is promoted by different strategic policies such as the European Green Deal or the new REPowerEU Plan. The role of geothermal energy in energy diversification and green transition of district heating systems to replace fossil fuels in urban areas is crucial.

The value of geothermal gradient which is the rate at which temperature increases with depth in the Earth’s crust, helps us to make a decision on the suitability of a geothermal system. The potential capacity of the system also depends on the expected water temperature and water flow.

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Main Features

  • Geothermal wells
  • Pipelines
  • Heat exchanger
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Photo by Viktor Hava

Advantages and challenges

+ Properly planned and operated geothermal systems have negligible environmental impacts.

+ Geothermal systems are very reliable and can deliver energy independently from changing weather conditions.

+ With geothermal energy, we can replace a great amount of natural gas, contribute to energy price stability and energy security.

+ As geothermal energy is amongst the greenest alternatives, cities and energy companies might require grants to finance investment costs.

–  Geothermal energy is not available or exploitable economically everywhere.

–  Geothermal investments have high drilling risks and costs which hinder the spread of this alternative energy.

–  Installing a geothermal system requires a long planning phase and has high investment costs.