RIYADH: A constant source of energy beneath the Earth’s surface is showing promise for Saudi Arabia’s cooling and desalination needs, and some experts believe it could even surpass the potential of solar and wind in some cases.

Unlike other renewables that depend on sunshine or wind, geothermal energy flows steadily underground, offering year-round baseload power. It can be tapped by drilling wells to bring heat to the surface, which is either turned into steam to turn turbines and generate electricity, or used directly for cooling and desalination.

For the Kingdom, which faces soaring demand for air conditioning and potable water, it could provide a cleaner and more resilient alternative to fossil fuels.

The King Abdullah University of Science and Technology, in partnership with KSA-headquartered TAQA Geothermal, is testing the potential of geothermal energy through a pilot project that seeks to guide national energy policies and encourage wider development of geothermal resources.

Thomas Finkbeiner, a research professor at KAUST and one of the leaders of the initiative, said the energy source could play a central role in the Kingdom’s future.

“I think it should be a major part of the effort and not just because of the sustainable energy it provides,” he told Arab News.

“Alternative solutions for district cooling and desalination would reduce domestic petroleum consumption … and decentralize the grid, which makes the grid less vulnerable and more resilient.”

Geothermal required “a multidisciplinary collaboration that will lead to new technologies in multiple fields and generate employment opportunities for young engineers and scientists,” he said.

He also highlighted its global potential.

“Absolutely it can play a major role, and unlike solar, wind and water, which are limited by geography and climate, geothermal is available everywhere and all the time … it provides baseload and complements all other renewable energies. Thus it is not a competition and a question of one or the other.”

Hurdles and perceptions

Despite these advantages, geothermal accounts for less than 0.36 percent of global electricity generation, according to a paper by the King Abdullah Petroleum Studies and Research Center. Current installed capacity worldwide is just 16 gigawatts, compared with about 2,000 GW of solar.

Finkbeiner said limited understanding and perception had contributed to the discrepancy.

“I think part of it is marketing and not scientific. The efficiency and reliability of geothermal in some cases surpasses solar and wind but these two get more attention in the news,” he said.

“Another factor is the high upfront capital expenditure resulting from drilling — in other words, economics.”

The cost of geothermal development remains one of its biggest hurdles. Exploration is expensive and construction demands major investment in drilling, infrastructure, power plants and transmission lines — factors that have deterred energy firms from venturing into the sector.

“The main challenges lie in successful drilling. This is the most expensive part of any geothermal project,” Finkbeiner said.

“Maintaining hole integrity during well construction is key … finding an aquifer with sufficient sustained flow rate is another challenge.

“However, all of these are well known and mitigated given the tremendous amount of pre-existing experience from the petroleum industry in KSA.”

On the environmental risk, he said: “Risks of minor earthquakes can never be excluded but should be minimal. Our project will not induce major pressure changes in any of the targeted aquifers.”

Saudi applications

Saudi Arabia’s geography makes cooling and desalination especially critical. About 90 percent of the Kingdom is desert and with water scarcity a pressing issue, desalination plants on the Red Sea remain vital for drinking water and agriculture.

But desalination is highly energy intensive and geothermal heat can provide a cost-effective and steady power source to drive the process.

“In the KSA it is mostly useable for district cooling and desalination, while some areas may also benefit from heating (during winter months),” Finkbeiner said.

“Another use is algae cultivation (algae as feedstock for animals). More important to temperature is the flow rate with which hot fluids come to surface — the higher the flow rate the more effective the geothermal system.”

The pilot project has already drilled a 400-meter well to measure subsurface temperatures and collect acoustic and thermal data. This is equipped with fiber optic sensors and geophones to guide future drilling campaigns.

“This information is very valuable for planning deeper geothermal wells, which is the next step in our project,” Finkbeiner said.

Economic and policy support

Experts believe geothermal could also provide new economic opportunities. Finkbeiner said that subsurface brines could hold valuable minerals such as lithium. If proven viable, this could create an additional income stream alongside clean energy production.

Preliminary assessments suggest Saudi Arabia has the potential to add 1 GW of geothermal installed capacity by 2035, contributing to its target of generating 50 percent of electricity from renewables.

However, reliable estimates of reserves will require further exploration and drilling, according to the KAPSARC paper.

Hesham Abualkhair, an economic policy expert, told Arab News that geothermal energy’s main edge was its reliability.

“Unlike solar and wind, it operates 24/7 without the need for large-scale energy storage,” he said.

“This characteristic can strengthen grid stability and reduce reliance on fossil fuel backup plants.”

For Saudi Arabia, ground source heat pumps could cut cooling demand by up to 60 percent compared with conventional air conditioning, while geothermal-powered desalination could lower costs and improve efficiency over time.

Still, Abualkhair said that geothermal was underrepresented in investor portfolios across the Middle East.

“While solar PV and wind projects attract multibillion-dollar investments backed by the Kingdom’s National Renewable Energy Program, geothermal remains at the pilot and feasibility stage,” he said.

He argued that policy measures could unlock investment, including risk-sharing funds, long-term power purchase agreements and streamlined licensing for subsurface resources, and pointed to models from Iceland, Turkey and Kenya, where government-led mapping, incentives and risk mitigation have spurred large-scale geothermal adoption.

Vision 2030

Geothermal could help Saudi Arabia achieve its Vision 2030 target of deriving half of its electricity from renewables, while ensuring grid stability, Abualkhair said.

Its 24/7 dispatchable nature would complement solar and wind, reduce reliance on fossil-fuel backup plants and support the growth of new green industries such as renewable-powered desalination and sustainable district cooling.

“Geothermal fits squarely within Vision 2030’s ambition to have 50 percent of power from renewable sources by 2030 while ensuring grid stability,” he said.

“Additionally, it can unlock new industries, enhance export potential and provide long-term, low-carbon infrastructure opportunities aligned with global ESG trends.”