Complex sentence: The UK government has efficiency measures to cut the UK's energy use by 11% by 2020, that enable to replace 22 UK power stations while providing a major boost to the economy and living standards.
Split into simpler sentences: The UK government has implemented measures aimed at cutting the UK's energy use by 11% by 2020. If achieved, this improvement would be sufficient to replace 22 UK power stations, while possibly providing a boost to the economy and living standards.