Computers can get hot. Even personal computers have little fans that whir quietly, blowing the heat away. Large computers generate even more heat. Although some might see this as a problem, in a cold country this can be an opportunity.
Deep in the bedrock below Uspenski Cathedral is a computer hall. It is cooled by district cooling and the heat the computers generate goes on to warm buildings in Helsinki. The heat created by the full hall will be enough to keep 500 single family houses warm and toasty throughout Finland’s cold winters.
“We monitor the overall energy efficiency of our computer hall and we intend to make this the most eco-efficient computer hall in the world,” says Jarmo Tuovinen, CEO of the IT firm Academica. “Just the district cooling and recovery of waste heat gives us an enormous advantage over others.”
Academica and Helsingin Energia have teamed up on this project. Most computer halls have an efficiency factor of 1.5 to 2. This number measures the ratio of total energy consumption and the amount of energy used for actual computing. The most efficient halls have a ratio under 1.5, but the hall under the cathedral is rated about 1. Helsinki is lucky because it already has the infrastructure for district heating in place, and much more could be done.
“We have a ready-made district cooling and heating network under the city centre, and plenty of underground premises,” explains Helsingin Energia’s Juha Sipilä. “There are many computer halls in the capital area that could be relocated under central Helsinki. Eco-efficient computer halls could really save significant amounts of primary energy and at the same time recover wasted heat for recycling. It is perfectly feasible that a quite considerable proportion of the heating in the capital city could be produced from thermal energy generated by computer halls.”
Text: DAVID J. CORD, HELSINKI TIMES