Part 3 I'm pleased to say that what with the relatively warm 2011 and our conservation efforts we had the lowest consumption of electricity and gas at home of any year yet, a bit over 1,500kWh ('units') of electricity and under 4,000kWh of gas. (A typical UK household is nearer 3,300kWh 'leccy and 18,000kWh gas.) With our solar PV exports we were just carbon-negative for power by my calculations.…