Increasing energy system flexibility and efficiency by using heat pumps in CHP stations

The project concludes that heat pumps are profitable in many cases and also increase the flexibility of the systems. Heat pumps require a usable heat source which make the systems more complex than traditional heat production units. Heat pumps are relevant in with many different heat sources and the project shows that utilization of industrial surplus heat is particularly interesting from an economic perspective. Further it is concluded that the surplus levy is not an obstacle in this regard.

The heat production price of heat pumps depend on many factors, but in the cases described, the heat pumps are economically viable with relatively short payback periods. This is partly due to low electricity prices in 2012 and 2013 and a reduced energy tax on electricity. This mean that heat pumps will provide the base load with a high number of yearly operating hours.

During colder periods the heat pumps will often be operated in in combination with other heat production units making efficient co-production essential. Daily or seasonal storages will provide greater flexibility regarding heat source, electricity price and heat demand. Though the current electricity market does not provide incentives for regulating services.

There have not been challenges regarding operation and maintenance, but it must however be considered that the heat pumps have not yet been operated for many years of their life expectancy.