The UK government has set a target to generate 10% of the UK's electricity from renewable energy sources by 2010. The Energy White Paper (2003) sets out the Government's aspiration to double that figure to 20% by 2020. It has additionally signed up to the legally binding Kyoto Protocol, which requires a reduction of greenhouse gas emissions by 12.5% of 1990 levels by 2008–12 and a reduction of CO2 emissions by 20% of 1990 levels by 2010. Regional and local authorities are required to contribute to the delivery of these national targets. The East Riding has an above-average potential to generate renewable electricity for Local Authorities in the region due its large wind energy potential. The East Riding of Yorkshire is set a target of 41 MW by 2010, and a target for 2021 of 148 MW for installed grid-connected renewable energy. There are operational wind farms at Lissett in Holderness and Out Newton to the north of the Humber estuary. There are single turbines at the Waste Water Treatment Works at Saltend and at Loftsome Bridge Water Treatment Works near Barmby on the Marsh. In addition, a number of other wind developments have either been given or are applying for permission. By late February 2009 there was existing developed capacity or planning approval for 140 MW of renewable energy from wind farm developments. The overall renewable energy target for 2010 and 2021 has therefore already been exceeded by wind energy proposals alone, assuming some of these schemes will be operational by 2010. The East Riding has also exceeded 148 MW, when other renewable energy types such as biomass are included in the calculation. The Humber estuary is to be used for trials of a tidal stream generator. If successful, it will be used to develop larger models which could be deployed in a 100-unit "renewable power station" capable of powering 70,000 homes.