Guardian: The majority of the UK’s least energy-efficient homes could be brought up to near-average green standards for less than £3,000, a new analysis claims today. The Energy Saving Trust says the cost of upgrading such properties may be less than many consumers think, while also revealing that the numbers of energy-inefficient homes in both the private and rented sectors has decreased. The Trust found that in 2008, the most recent year for which data is available, 17% of English …