Buildings in Albertslund have been heated by district heating since mid-1960’s. The present day heating sources are cinerated garbage/waste as well as cogenerated straw, wood pellets and natural gas bought from two big heating plants in the Copenhagen area and distributed to dwellings and businesses within Albertslund.
Since spring 2015 a part of the heating supply in the city is being delivered from a server company named Jaynet A/S, hosting other companies with cloud solutions and physical serverrack. The company used to skip all the excess heating to open air as a huge energy loss, but from May 2015 one GWh energy a year is being sold to the municipal non-profit district heating company ‘Albertslund Varmeværk’ (Albertslund Heatingplant) and distributed via the existing pipe networks without a few further investments than a oversized heat pump.
This heat pump transforms cooling from a number of server rooms to 75 degrees Celsius hot water, put to the main flow in the district heating pipes as well as heats the building itself. In fact it is a fairly simple, technical system, however challenging the world of taxes, tariffs and pricing.
This is nevertheless a win-win situation. Though the electricity costs for the heat pump are higher than the cost running traditional cooling of a server room, selling the heat provides a plus and a benefit for the server company. At the same time the heating company buys one KWh of heat cheaper than from the huge heating plants in Copenhagen. In this way both partners split up the advantage of regained heat.
Payback time for the whole setup is reduced to 8-9 years with the present day buyingcosts for heat pumps. In the future costs are expected to fall, which could make investments and setups like these even more interesting.
The development of the setup has been a lucky public/private cooperation done on local basis. The communication has hereby been short, personal and constructive. The nonformal Danish approach tends to reduce barriers. All parties in this process were driven by enthusiasm as well.
The impact of reusing heat is less CO2 emission from heating plants. The introduction of low temperature district heating (LTDH) in Albertslund welcomes these heat pump-solutions, due to the fairly low temperature, heat pumps usually deliver on the output-side. Albertslund has taken a step forward into a new energyfuture.
Source: State of Green