Energy World was a demonstration project of 51 low-energy houses constructed in the Shenley Lodge area of Milton Keynes, United Kingdom. The project was promoted by the Milton Keynes Development Corporation and culminated in a public exhibition in August and October 1986 that attracted international interest. It was a significant landmark in the design and construction of low-energy housing, and in the development of energy efficiency evaluation tools. It has had a long-term impact on Government policy and within the national house-building industry, insofar as the progressive 'tightening up' of the energy section of the Building Regulations has largely been founded on this pioneering work. The houses were designed to be at least 30% more efficient than the Building Regulations then in force. The architecture and technologies used was very varied, and included designs from Canada (the first R-2000 house in the UK), Denmark, Finland, Germany, and Sweden. Although it was later removed, the exhibition also featured a wind turbine, then an uncommon sight. As of 2004 the houses were continuing to sell for 3% above the price of other housing in the area . Energy World was one of several low-energy projects built in the Milton Keynes area. These included trials on a number of individual houses and the construction of 177 houses in the 1970s Pennyland project. Following the success of Energy World, 1,200 dwellings were built to the same (or better) energy standard in the rest of Shenley Lodge (known as 'the Energy Park'), and the same standard was subsequently applied Citywide. The concept of the Energy Park was extended into non-residential buildings built across Watling Street in Knowlhill where a number of low energy office buildings have been constructed including the two phases of the headquarters buildings of the National Energy Foundation. Home energy efficiency rating schemes Another area where Energy World continues to have an impact derives from the Milton Keynes Energy Cost Index (MKECI) , which was used to calculate the energy efficiency of the Energy World houses. Based on the results and feedback from Energy World, this was to evolve into the UK's first national energy efficiency rating scheme for buildings, with the launch in 1990 of the National Home Energy Rating scheme (NHER) . This, in turn, gave rise to the introduction in 1995 of the Standard Assessment Procedure (SAP) rating system used in the national Building Regulations and in home Energy