Will Mathis, Bloomberg
Four decades after it supplied its last coal to the Netherlands, a shuttered mine near the German border is feeding low-emission air conditioning to homes nearby. The cooling system collects some of the millions of gallons of water held in flooded mine shafts about 200 meters (650 feet) below the surface and pumps it through a network of underground pipes. The cold water flows through a neighborhood of 400 homes and a handful of nearby businesses, keeping them cool during the summer. In the winter, warmer water from deeper in the mine is used to heat the same buildings.
The efficiency and low power requirements of the system in Heerlen, developed by Mijnwater BV, means it consumes 65% less energy than traditional heating and cooling, according to the company. Such networks, known as district cooling—or heating—systems, are on the rise as towns and cities look for ways to cut emissions. They point the way to solving one of climate change’s biggest challenges: As Earth warms and summer temperatures break records, demand rises for air conditioning, boosting energy consumption and the climate-warming emissions that come with it. Demand for power to cool homes and businesses is likely to more than double by 2050 and account for about 13% of the world’s electricity consumption, according to BloombergNEF. It’s a dangerous feedback loop that threatens to accelerate global warming. “As human beings, we can’t keep installing air conditioning systems that aren’t efficient for this demand,” says Olivier Racle, director of district heating and cooling for the French utility Engie SA.