The recycled heat from the data center, being built by IT and telecom services company Academica, could add about 1 percent to the total energy generated by Helsingin Energia's system in the summer.

The plan calls for the data center to first get cold water from Helsingin Energia's system. The water then goes through the data center to cool down the equipment. Next, the now warmer water flows to a pump that heats the water and sends it into the district heating system. The pump also cools the water and sends it back to the data center.

The data center will go live at the end of January, and will at first measure 500 square meters.
Academica had always planned to use water to cool the data center and lower electricity bills for customers. The idea to recycle excess energy came later. However, recycling could end up playing an important role.
(This story summarized from ITworld and full story can be reached their web pages)