Helsinki public energy company Helsingin Energia will recycle heat from a new data centre to help generate energy and deliver hot water for the Finnish capital city.

The recycled heat from the data centre, 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, according to Juha Sipilä, project manager at Helsingin Energia.

"What's important is that we use the resources we have efficiently, and don't waste energy," said Sipilä, who sees this project as a way to prove the technology works and pave the way for use on a larger scale.

The data center is located in an old bomb shelter and is connected to Helsingin Energia's district heating system, which works by pumping boiling water through a system of pipes to households in Helsinki.

The plan calls for the data centre to first get cold water from Helsingin Energia's system. The water then goes through the data centre 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 centre.

The ability of the heat pump to both heat and cool water is what makes it special, according to Sipilä. The pump is also very efficient, you get five times the amount of energy you put in, he said.

The data centre will go live at the end of January, and will at first measure 500 square meters, according to Pietari Päivänen, head of sales at Academica.

What Acedemica gets from this is cheap cooling power, five times cheaper than what it would pay for traditional electricity, said Sipilä.

Academica had always planned to use water to cool the data centre and lower electricity bills for customers. The idea to recycle excess energy came later. However, recycling could end up playing an important role, according to Päivänen.

"If all the data centres in Finland were to use the technology they could power a mid-size Finnish city," said Päivänen.