In several hundred houses in Fredericia, the Christmas mood was challenged when the power suddenly disappeared on Christmas Eve.
On Christmas Eve, the temperature was low, which meant that the heat pumps in the neighbourhoods worked at full speed. At the same time, everyone prepared Christmas dinner – in Denmark ducks and pork roasts. It overloaded the electric grid to an extend that the power disappeared. 335 homes were without power.
When to use heat pumps and when district heating?
The municipalities must take action and be better at making heating plans, says professor of energy planning at Aalborg University, Brian Vad Mathiesen. We need some strategic heating plans, so you know where using a heat pump is the right solution and where it’is appropriate to use district heating, he says. Brian Vad Mathiesen bluntly says – that you should only be allowed to have a heat pump if you have no neighbours.
If you have neighbours, you should consider heating your house with district heating instead so that many heat pumps do not overload the electricity grid at the same time. – Otherwise, we risk that we have to over-invest in the electricity grid and that in the short term, we get the type of interruptions that we had over Christmas, says Brian Vad Mathiesen.
Heat pumps overturned the load
Trefor – the local utility company believes that 57 new heat pumps knocked out the power grid in the specific case. And we will see more of that in the future, predicts the electricity supply director in Trefor, Per Sørensen. – If the number of electric cars and heat pumps increases faster than we expect, it is a big challenge we face in the future.
The underground cables are not geared at all to high electricity consumption, and therefore Trefor expects to spend six billion kroner over the next 20 years. We must strengthen the network, establish new cables, and strengthen the plant to meet the demand that comes, says Per Sørensen.
Investment of DKK 41 billion awaits
Trefor is far from the only electricity company to start the excavators. The Climate Partnership for Energy and Supply, which brings together energy companies and interest groups, estimates that DKK 41 billion will be spent over the next 8-9 years. Otherwise, the grid cannot keep up with the same pace we buy electric cars and heat pumps.