How Aquifer Thermal Energy Storage (ATES) is catching on in Japan

13 januari 2017

Japan’s energy system is under pressure. With little to no fossil fuel reserves it is heavily reliant on fossil fuel imports. This puts a heavy burden on the national budget and makes the country vulnerable to rising oil prices. The Japanese government is currently looking for solutions that reduce energy demand and increase renewable energy production. A Dutch renewable heating and cooling technology called Aquifer Thermal Energy Storage (ATES) might become part of this solution.

How does an ATES system work?
The ATES system uses underground aquifers to store thermal energy across the seasons. Naturally cool groundwater (+/- 10°C) is pumped up through a well and used directly for cooling. The resulting warm groundwater is injected in a second well in the same aquifer where it forms a warm bubble. During colder days the flow is reversed and the warm water can be used again for heating. The ATES system is very energy efficient reducing the primary energy use for heating by 60% compared to a conventional gas fired boiler. The primary energy demand for cooling is decreased by about 85% compared to conventional cooling systems.

IF Technology introduced the ATES system in the Netherlands almost 30 years ago. By now it has become the standard in the commercial building sector. As a result, the Netherlands has become the largest market for ATES systems in the world. Until now the benefits of the ATES system have gone mostly unnoticed by the rest of the world. But that seems to be changing. In Japan's search for energy efficient technologies they came across the ATES technology and it caught their interest. KEPCO, one of Japanese electric power companies decided to build a pilot project in Takasago and we are helping them realise it.

The first Japanese ATES system
An ATES system requires a suitable aquifer to function. The project location was made up from volcanic deposits and ocean sediments. Even though these layers form suitable aquifers, the structure is quite different from that commonly found in the Netherlands. This created some challenges at first. A drilling company from abroad with experience in this type of formation was asked to perform the drilling. Our Japanese partners did a great job with adapting to the challenges and assisting the drilling crew. The two wells have now been drilled, screens were installed and the wells are producing flow above expectation.

We are proud that the two ATES wells have been completed and resulted in a valuable learning experience. Due to the success of the first project we got an immediate go for the second demo project situated in the middle of Osaka city near the central station.

The value of ATES systems
Even though the ATES system is a success in the Netherlands we feel that the technology is underutilized on an international level. This is why we are very pleased with Japan seeing the value of ATES systems to reduce their dependence on fossil fuels. We hope that other countries will take an interest as well. We are always open to questions, ideas or requests so feel free to contact us if this technology sparks your interest.