The Regulation on Indoor Heating and Air-conditioning Systems (RITE), promulaged by the Royal Decree 1027/2007 of 20 July 2007, came into force on 29 February 2008 after revision. The Regulation forms the basic legislative framework laying down the energy efficiency and safety requirements to be met by heating and cooling systems in buildings, with a view to meeting comfort and hygiene demands, during their design and sizing, construction, maintenance and use. It also specifies compliance procedures. The approval of this Regulation implies an advance in the transposing of the Directive 2002/91/EC on the energy performance of buildings, setting minimum energy efficiency requirements to be met by thermal systems in new and existing buildings and a procedure for the periodic inspection of boilers and air conditioning systems. The more stringent energy efficiency requirements laid down in RITE 2007 are: - Improved energy performance of heating and cooling equipment, and of equipment designed to transport fluids. - Improved insulation of heat transport equipment, pipes and fluids. - Better regulation and control to maintain the design conditions envisaged in air-conditioned premises. - Use of available renewable energy sources, particularly solar energy and biomass. - Incorporation of subsystems for heat recovery and utilisation of residual energy. - Mandatory metering systems for consumption for collective systems. - Gradual elimination of more polluting solid fuels. - Gradual elimination of less efficient generating equipment. This Regulation also forms one of the development programmes within the Energy Saving and Efficiency Plan, and will also help to achieve the objectives laid down by the Renewable Energy Promotion Plan, by encouraging greater use of solar thermal energy, particularly in the production of domestic hot water.