The deeper you drill, the warmer it gets.
According to a recent published research from the Geothermal Energy Association (GEA), the market for geothermal energy is exploding globally. Due to climate change and the internationally defined restrictions on CO2 emissions, the need for clean energy sources is rising all over the world. Geothermal energy has proven to be the ultimate solution, tapping into the earth’s natural heat. The principle is beautiful and simple. You drill two deep holes in the ground and pump up hot water. The heat is used, and the water that has cooled down then gets pumped back into the earth. The deeper you, drill the hotter it gets. In the Netherlands, the temperature at 1500 meters depth is around 50-60℃. But drill to 5500 meters and it soon reaches a temperature of 175℃. Every 100 meters, the temperature goes up by around 3℃.
Worldwide, the renewable energy revolution is causing a shift in which countries are energy suppliers. East Africa, Kenya and Ethiopia are already building power plants larger than 100 megawatts. Countries such as Chile, Argentina, Colombia and Honduras have a huge potential below their feet. According to the GEA, Chile started to set up about 50 geothermal projects. Indonesia is expanding its capacity to 4400 megawatts.
Iceland in particular, known as the Saudi Arabia of geothermal energy, has been leading the pack for years. In the city of Reykjavík, 99% of households and many industrial companies use geothermal heat. There is not a single household in all of Iceland that still uses boilers or water heaters that run on natural gas or oil. And that has also come to the attention of the Chinese. A month ago, the Iceland GeoSurvey and the China Geological Survey signed a cooperation agreement.
Even though the Netherlands is a low-lying country, geothermal heat is located deep down, which makes the drilling and additional installations expensive. By comparison: drill down 1500 m on Java and Sumatra and the water is already 200℃. There is still a lot we don’t know about what goes on below the earth’s surface, so in the coming years, explorations below the Dutch soil will need to tell us more.
“We want to know which cities we could run on geothermal energy,” says project manager Eveline Rosendaal of Energy Management Netherlands (EBN). At the end of this month, EBN will launch a proposal to kick the use of geothermal energy in the Netherlands into a higher gear.
This post is also available in: Dutch