A Japanese onsen with water cascading down a wooden structure into a natural spring.

Japan is about to close 100 coal plants – here’s what to replace them with

In 2018, coal-fired power accounted for 32% of Japan’s total power generation, followed by natural gas-fired power generation at 38%. Japan has 140 coal power plants and around 110 of them are seen as inefficient. The Japanese Government now urges the closure or suspension of about 100 of these by 2030 in the face of international pressure for a transition to greener alternatives, according to Nikkei’s Asian Review.

For many countries coal power plants fill the need for a stable and reliable baseload energy. Although the increasing additions of renewable energy sources such as wind power and solar power are changing the energy mix, these renewable alternatives alone can’t seem to replace coal entirely. The reason behind this is the natural intermittency of wind and solar power, the fact that they vary with the weather. To replace the stable coal generated electricity the grid owners need a sustainable and dispatchable baseload, something that works 24/7, independent of the weather conditions.

One such energy source is Geothermal Heat Power, utilizing the stored heat in the earth in geologically active areas of the world. In Japan, there is a power output equivalent to 23 gigawatts (GW) lying beneath the surface in the form of geothermal energy, the world’s third-largest store, according to the International Renewable Energy Association (IRENA). This can be compared to the world’s total installed capacity of geothermal power of 13.9 gigawatts (GW) in 2019.

We believe that distributed geothermal heat power utilizing low-temperature resources is the missing piece of the renewable energy puzzle and has the chance to revolutionize the Japanese energy system. By focusing on resources at lower temperature the potential of places that can harness geothermal heat power increases widely and enables it to become a distributed baseload for communities all over Japan.

According to IRENA, more than half of Japan’s geothermal resources are located around national parks or near the country’s 27,000 thermal springs. For centuries, communal baths and hot springs, onsen, have been an important part of the Japanese culture. However, many landowners in rural Japan have struggled to find a commercial use for their land as the spa business has been in decline for several years. Through Climeon’s small and discrete power systems, these spa owners now have the possibility to add a new income stream, without harming the spa or the nature, while at the same time contributing to the country’s green energy transition by providing a renewable baseload that can replace coal.

See Climeon’s first geothermal power plant in connection to a Japanese Onsen here.