22 May 2002
Heat pumps offer the possibility of reducing energy consumption significantly, mainly in the building sector, but also in industry. The second law of thermodynamics shows the advantages: While a condensing boiler can reach a primary energy ratio (PER) of at best 105 % (i.e. the boiler efficiency ?B; the theoretical maximum would be 110 %, based on the lower calorific value), heat pumps achieve 200 % and more. Presently about 130 million heat pumps with a thermal output of 1300 TWh/a are in operation world-wide, reducing CO2 emission by about 0.13 Gt/a. The potential for reducing CO2 emissions assuming a 30 % share in the building sector using technology presently available is about 6 % of the total world-wide CO2 emission of 22 Gt/a. With future technologies up to 16 % seem possible. Therefore, heat pumps are one of the key technologies for energy conservation and reducing CO2 emissions.