30 October 2014
Annex 38 was concerned with solar and heat pump system for space heating and domestic hot water. A total of 55 experts from eleven countries attended some or all of its eight meetings over the period 2010 – 2013.
The main results are as follows:
• A survey of the market in 2010 was responded to by more than 80 companies.
• Four generic categories of SHP systems have been proposed and used throughout the Annex period, and taken over by several other teams in research projects.
• An energy flow chart solution was developed and used by all 32 Annex projects.
• Definitions of all performance indicators (from COP to SPF+) are now available and form a basis for a future EU standard.
• A simulation framework was developed from previous IEA work and proved to be a great tool for comparing SHP systems
• Laboratory testing procedures for any SHP system have been developed and used and described.
• 32 systems in the field were monitored by several teams, and 20 have been reported with a common reporting format.
• Not surprisingly, a high variance of SPFs was observed and the reasons why explained. The management of the store is one of the important ones, together with the overall control strategy and the temperatures of heat distribution systems.
• Validated models are now available for many SHP configurations.
• A comparison of different configurations with the same framework was produced and shows what solar heating can contribute (or not) to heat pump systems
• The final report from the project, in the form of a handbook, is of high scientific and technical quality and will soon be sent to the publisher. Publication date is planned for autumn 2014.
• An economic analysis model to enable systems to be compared has been developed, and will be included in the handbook as Chapter 8.
• S + HP systems are now considered as “standard technologies”, although there is still some work to be done to arrive at optimum high performing solutions.
– All categories of systems can deliver SPFs of 5.0 or more if solar energy is also used, provided that careful designs and control strategies are applied.