As Saudi Arabia looks to its energy transition, experts are considering how to develop geothermal energy in the kingdom. With a geography comprised of numerous volcanoes, there is considerable potential for harnessing this renewable energy resource in the country. And the benefits are numerous: Geothermal energy works constantly, has a small footprint, and can be used to produce low-carbon electricity. It does not depend on the weather like solar and wind power, which makes it more reliable. Saudi Arabia’s recent commitments to achieve net-zero emissions by 2060 and the new Saudi Green Initiative will drive more investments toward renewables and increasingly greater incorporation of geothermal energy.

Geothermal Energy Potential in Saudi Arabia

According to some reports, Saudi Arabia has set a goal of achieving 1 gigawatt of geothermal energy capacity by 2030. Many studies have looked into the potential for geothermal in Saudi Arabia and have found it to be surprisingly good in some areas. There is a lot of potential in the Harrat Rahat volcanic lava field in western Saudi Arabia, around Mecca and Medina, as well as Jazan and Al Lith on the Red Sea coast. That the volcanic harrats are not far from the demand centers for electricity and water in western Saudi Arabia also helps for accessibility.

Geothermal Energy 101

What sort of geothermal energy Saudi Arabia can or should use depends on the geology of the areas to be exploited as well as what might be economically, politically, and socially workable.

Where there are very hot rocks down deep, geothermal energy uses the heat of the Earth to turn water into steam or uses geothermal water, or geothermal brine, from deep below the Earth’s surface, to create steam. The steam turns a turbine, which generates electricity. Geothermal heat comes from the formation of the Earth and the natural radioactivity of the Earth deep down. Since its fuel source is the heat of the Earth, geothermal can continuously generate electricity in areas where the geology is appropriate.

However, geothermal energy does not always require extremely hot rocks from deep below the Earth’s surface. Saudi Arabia could also exploit lower temperature geothermal areas for binary geothermal electricity generation. In this process, the warm geothermal brine is brought up to heat working fluids, such as methanol or ammonia. When they are brought to a boil, the working fluids become steam, which turns the turbine.

Alternatively, dry steam plants use steam that flows directly from the geothermal reservoir to turn the turbine. And flash steam facilities bring high-pressured hot water from underground and convert it into steam to turn the turbine.

Other Applications for Geothermal Energy

Outside of electricity production, Saudi Arabia can use geothermal energy for heating and cooling with geothermal heat pumps. These require digging, piping, plumbing, and electricity expertise – skills that Saudi Arabia has developed over the years to advanced levels with its oil industry. In using heat pumps, Saudi Arabia could reduce the need for other sources of heating and cooling, and, in so doing, would save oil and gas resources and decrease electricity costs.

Heat pumps could be a source of cooling and heating that is far less fuel intensive than using fossil fuels. In most areas of the world, 21 to 40 feet below the surface there is a constant temperature year round of approximately 50 degrees Fahrenheit. During days that are colder than 50 degrees, the relative warmth of the Earth can be brought up via underground pipes and fans or heat exchangers connected to the basement of a building, for example. And, on hotter days, the coolness of the Earth can similarly be brought up. Heat pump systems could also be centralized and shared across buildings through district heating and cooling systems.

Saudi Arabia could also use geothermal energy for desalination. Saudi Arabia produces a huge amount of freshwater with carbon-intensive, oil- and gas-fired plants. Turning to geothermal energy to fuel some of Saudi Arabia’s desalination plants could give Saudi Arabia a cleaner way of creating freshwater.

Geothermal energy has many other direct applications. It can be used for pasteurization, drying fruits and vegetables, and heating greenhouses and aquaculture ponds, or fisheries. More widely incorporating geothermal energy will reduce the use of fossil fuels and decrease Saudi Arabia’s carbon dioxide emissions.

Overcoming Hurdles in Saudi Arabia

There are several barriers to Saudi Arabia incorporating geothermal energy, though all can be overcome. For example, lack of awareness about and acceptance of geothermal energy can be addressed through education and strategic communications. The fact that Saudi Arabia has so much oil that is inexpensive to get out of the ground also works against the development of such energy systems. The process of exploiting hot rocks deep down can involve costly drilling. However, the Saudis already have the drilling expertise with Saudi Aramco and others. Additionally, the Saudis can capitalize on the process of drilling oil wells: When a deep oil or gas well is drilled, there is likely to be a simultaneous discovery of hot water. Oil wells that have seen declines in their profitability might be repurposed for geothermal resources as is being considered in the United States. There will also need to be investment into developing infrastructure around geothermal wells. This is another area that could benefit from the expertise of Saudi Aramco as well as Saudi electricity companies and their contractors.

There are many vested interests surrounding oil and gas that could obstruct the development of geothermal energy as an alternative. To get geothermal investments off the ground, or in the ground, there may be a need for government support politically and in the form of financial incentives for Saudi and foreign companies to get involved. And as geothermal energy is a new idea for the Saudi public, there may be a sense of risk associated with such investments.

However, geothermal energy has been employed in various capacities for hundreds of years in many parts of the world. And education and training of Saudis, especially at a young age and through school curriculums, about geothermal energy and the massive potential it presents for the country will likely help raise Saudis’ comfort level. Developing geothermal facilities in the country will likely bring about more research and development about its potential and stimulate greater investment in geothermal development. This will also bring more confidence that these systems can work in the country, completing the needed virtuous circle.

Benefits of Geothermal Energy

As Saudi Arabia advances its energy transition, the kingdom could find numerous benefits in more resolutely incorporating geothermal energy in its energy mix. Saudi Arabia could repurpose oil and gas wells that have become unprofitable and even those that may be shut in as Saudi Arabia’s energy transition progresses. Further, the more electricity that is produced by geothermal energy, the less oil and gas is needed to generate that electricity. The use of shallow geothermal heat pumps could save massive amounts of energy and reduce electricity costs. Geothermal desalination and geothermal electricity production will not use any oil and gas, especially if the facilities and pipelines needed are electrified by geothermal energy. As a dependable energy source that can work 24 hours a day regardless of the weather, geothermal energy can help enhance energy diversification, reliability, resilience, and security.

Geothermal energy could also help Saudi Arabia reduce its carbon footprint as the kingdom works to adopt a circular carbon economy framework. Geothermal energy has substantially less of an environmental impact than burning fossil fuels. Geothermal systems produce a much lower level of  greenhouse gas emissions than oil and natural gas do, emitting only small amounts of sulfur dioxide and carbon dioxide. And using geothermal energy could also improve air quality.

As Saudi Arabia works to achieve its net-zero commitment for 2060 and advance the goals of the Saudi Green Initiative, it will find vast opportunity in developing its expansive geothermal resources. While there are certainly going to be difficulties involved – to build public support and the necessary infrastructure – for volcano-rich, geologically endowed Saudi Arabia, geothermal energy can open new pathways for the kingdom’s energy leadership.