The bank was created in 1948 after the Second World War as part of the Marshall Plan for the reconstruction of Europe. The KfW Förderbank (KfW promotional bank) is today its largest business unit, committed to housing and environmental protection. KfW introduced the Efficiency House Standard in 2009, to identify levels of energy efficiency in houses and provide loans or grants accordingly. Its activities devoted to bringing down CO2 emissions align with a strategy designed by the Federal Ministry of Economics and Technology (BMWi) in 2010, following the decision to speed up the pace of nuclear energy phase-out. This strategy outlined the directions to be privileged in the following years to achieve the desired level of energy efficiency. Among others, it asked to significantly raise the efficiency standards for buildings, to increase funds available for building improvement, and to implement tools to help ensure that new buildings gradually comply with the futureEuropean standards for nearly zero energy buildings. The KfW created promotional programmes targeting private buyers and homeowners, landlords and housing companies, to support refurbishment of older residential buildings with grants or loans. The German government announced in its “Energy Concept” strategy that it aims at reducing CO2 emissions by 80% in 2050 (the base year is 1990). Between 1990 and 2010, annual CO2 emissions have fallen at an average annual growth rate of -1.1%. This rate is not large enough to reach the 80% reduction goal; emissions should decrease at a rate of 3.4% per year from now on. The most important sector contributing to CO2 emissions is the production and distribution of energy and water (42% of total emissions), and the second-most important one is that of private households (22%). The government has thus decided that efforts must be focused on two pillars: increased energy efficiency in existing buildings, and a larger share of renewable electricity. In order to ensure a reduction of energy consumption in existing buildings, it has decided to promote their rehabilitation, and has committed to carrying out thermal retrofits on 2% of the building stock each year. The realization of these goals is precisely what KfW's promotional programs are targeting. The bank has set six levels of promotional incentives for energy efficiency refurbishment activities, expressed as Efficiency House Standards 55, 70, 85, 100, 115, and “Monument”. These numbers represent the energy consumption of the housing unit as a percentage of the maximum primary energy requirement specified by the Energy Conservation Ordinance (EnEV). The lower the rating, the greater the energy efficiency.