The main objective of this Task is to assist in a strong and sustainable market development of large solar district heating and cooling systems. The systems can include seasonal storages and/or heat pumps/chillers.

This objective will be achieved by optimising system configurations and components - using a systematic approach:

• at the system level: using the best relative sizes and combinations of solar thermal, heat pump, seasonal storage and others, control strategies - taking into account the local framework conditions
• at the component level: improve costs, performance and lifetime

The main focus is on the system level: How to match the actual system configuration to the actual needs and local conditions including the surrounding regional energy system (free electricity market). Or in other words: For the given conditions of load and energy prices, which system type and size to choose to have a competitive heat price and a large solar fraction.

It is important that the systems are installed and controlled/operated properly in order to perform well. To secure that, guidelines and standards have to be updated and developed and recognised performance guarantee procedures established.

To push the market development, a strong effort will be done in promoting the benefits of the technologies and results from the Task to the decisions makers in the sectors of district heating and cooling and process heating and cooling. The issue of financing the “upfront investment in 25 years of heat production” will be dealt with - and models for services of Energy Service Companies (ESCo’s) will be proposed and sought tried out.

The scope of the Task covers large-scale solar thermal systems – pre-heat systems as well as any combination with storages, heat pumps, CHP-units, boilers, etc. for the supply of block and district heating & cooling.

Any type of solar collector is in principle possible:

• liquid based
• air based
• flat plate (glazed / un-glazed)
• evacuated tubes (direct / heat pipe)
• concentrating (tracking / stationary)

Concerning heat pumps the main focus will be on heat pumps driven by electricity. However during the course of the Task it might be become relevant to consider also thermally driven heat pumps.

Concerning thermal driven cooling machines (chillers) no restrictions in scope.

Concerning storages the main focus will be on seasonal storages.