01 May 1993
On the one hand heat pumping is a mature and proven technology, with readily available equipment, offering in many cases a cost-effective way to save energy and benefit the environment. On the other hand, heat pumps still offer tantalising development potential. The possibilities to improve efficiency, to raise output temperatures and to reduce costs are far from exhausted. Equally important is the development of integrated energy systems that incorporate heat pumps. In particular, the combination of heat pumps with thermal storage systems can offer major economic and energy efficiency benefits. Thirty-two participants from seven countries addressed all these development challenges at this workshop, focusing on advanced combinations of heat pumps and thermal storage. Particular attention was paid to the results from the trendsetting Japanese Super Heat Pump Energy Accumulation System (SHPEAS) Programme, concluded March 1993. The ambitious targets of this nine year programme included a near doubling of the COPs that were customary in the early eighties, combining heat pumps with chemical heat stores which had yet to be developed, and high temperature/high efficiency systems. Presentations from outside Japan covered the combination of heat pumps with seasonal aquifer storage, and innovative adsorption systems. Some highlights from the presentations were:
· The super heat pump programme met all of its main targets
· Heat pumps combined with ice or water thermal storage are a cost effective way to achieve electric load levelling.
· Seasonal thermal storage in aquifers is technically mature, and in many cases economic.
· The SWEAT system, a modular adsorption heat pump/heat storage unit, can significantly reduce heating and cooling costs.
· Adsorption developments in France have resulted in output temperatures of 220°C in pilot plants
In conclusion the workshop participants discussed the state of the art, the technical and commercial potential, and the possibilities to enhance market penetration of heat pumps with thermal storage. The best potential was identified in the commercial sector, when both heating and cooling is required. In general, cost reduction is the main challenge.