Heat pump use in Scotland – an evidence review

Heat pumps are an efficient way of producing heat from electricity; they operate by capturing the latent heat in the air, ground or water and using it for heating.

Heat pumps are expected to play a significant role in decarbonising heat in Scotland; the Climate Change Committee has described them as a ‘low-regrets’ option, and they feature prominently in Scotland’s Draft Heat in Buildings Strategy.

However, heat pump efficiency can vary across the heating season and in different buildings, meaning the costs and impacts on wider energy systems depend on the context.

This desk-based review looks at evidence on how heat pumps currently, or are likely to, perform in practice in Scottish buildings. The research identifies best practice relevant to Scotland and gaps in the available evidence.

The scope of the research was for both domestic and non-domestic buildings. However, the majority of the relevant datasets relate to domestic settings.

Key findings

• Poor heat pump performance is most likely to arise due to poor design and specification. This means appropriate design and installation are the most important considerations to ensuring heat pumps perform well in Scotland.
• Heat pumps are a mature heating technology used in several European countries, including countries with colder winters than Scotland. The review found no evidence to suggest that heat pumps could not operate effectively or efficiently in Scotland. 
• The review suggests there is occupant satisfaction with heat pumps.
• There is evidence that heat pump performance could be maximised by building confidence in heat pump technology among consumers and the supply chain. 
• Where running costs were monitored, heat pumps were cheaper to run than previous electric, oil or LPG heating systems and are a key outcome for occupant satisfaction.