heating needs of the entire country (Wood, 1985). In Denmark in 1985, district
heating systems supplied 42% of space heating, with heat being transmitted
20 km or more in hot pressurized water. In West Germany in 1985,
4 million dwellings received 7 kW per dwelling from district heating. Two
thirds of the heat supplied was from power stations. In Vasteras, Sweden in
1985, 98% of the city’s heat was supplied from power stations.
147Heat pumps are roughly four times as efficient as a standard electrical barfire.
Some heat pumps available in the UK already have a coefficient of peformance
bigger than 4.0 [ ]. Indeed there is a government subsidy for
water-source heat pumps that applies only to pumps with a coefficient of
peformance better than 4.4 [ ].
Commercial ground-source heat pumps are available with a coefficient of
performance of 5.4 for cooling and 4.9 for heating [ ].
153Air-source heat pumps with a coefficient of performance of 4.9... According
to HPTCJ (2007), heat pumps with a coefficient of performance of 6.6 have
been available in Japan since 2006. The performance of heat pumps in Japan
improved from 3 to 6 within a decade thanks to government regulations.
HPTCJ (2007) describe an air-source-heat-pump water-heater called Eco Cute
with a coefficient of performance of 4.9. The Eco Cute came on the market
in 2001. www.ecosystem-japan.com.
Further reading on heat pumps: European Heat Pump Network