The main goal of this Task is to investigate new or advanced solutions for storing heat in systems providing heating or cooling for low energy buildings.

The first objective is to contribute to the development of advanced storage solutions in thermal solar systems for buildings that lead to high solar fraction up to 100% in a typical 45N latitude climate. The second objective is to propose advanced storage solutions for other heating or cooling technologies than solar, for example heat pumps or fossil boilers in order to reduce cycling and thus to reduce pollutant emissions due to partial combustion.

The ambition of the Task is not to develop new storage systems independent of a system application. The focus is on the integration of advanced storage concepts in a thermal system (solar, heat pump or boiler) for low energy housing. This provides both a framework and a goal to develop new technologies.

The Subtasks are:

• Subtask A: Evaluation and Dissemination (Subtask Leader in 2006: Switzerland)
• Subtask B: Chemical and Sorption (Subtask Leader: Chris Bales, Sweden)
• Subtask C: Phase Change Materials (Subtask Leader: Wolfgang Streicher, Austria)
• Subtask D: Water (Subtask Leader: Harald Drueck, Germany)

The teams within Subtasks B, C and D are asked to set up a TRNSYS model of their system based on experimental work in order for Subtask A to compare all the options in terms of heat and cold storage for a reference case of a single family house in four climates.