Theresa May’s delay in giving final approval to Hinkley also gives us a chance to look more holistically at future energy policy. With around 4.5 million UK households suffering from fuel poverty and over 30% of greenhouse gas emissions attributable to heat, even with 100% renewable electricity we would still need to do a lot more to cut greenhouse gas emissions from the heat sector to meet climate targets. In Aberdeen councillors have just unanimously agreed to an £11m investment to expand the City’s district heating network — offering 350 more homes the chance to save on their energy bills. Aberdeen Heat and Power (AHP) has grown substantially since it began in 2002 and currently provides heat for 2,361 flats in 33 multi-story blocks, two sheltered housing blocks and 13 public buildings. District heating networks can be fed with heat from a range of sources from gas-fired and biomass-fired Combined Heat and Power (CHP) stations which also generate electricity, to deep boreholes which extract geothermal heat from underground. In Glasgow heat is being captured from trapped water in old flooded coal mines via heat pumps. In Lerwick Shetland Heat and Power is hoping to extend its heat network by installing a 2MW heat pump made by Star Renewables in Glasgow to abstract heat from Lerwick Harbour. In the London Borough of Newham there are plans to harness the energy from ‘fatbergs’, the bus-size balls of grease which cost Thames Water an estimated £1 million a month to remove from its sewers. Despite enthusiastic support for energy storage technology both sides of the political spectrum –including The Telegraph right – the government is yet to be convinced we can cope with a high percentage of intermittent renewables. This is where CHP-district heating networks could be crucial. In Germany, for instance, as wind and solar PV take on a greater proportion of total electricity production, CHP plants are expected to take on the role of providing more flexible electricity generation. At the moment CHP plants focus on meeting the demand for heat. Electricity production is seen as a useful by-product. But in future the focus will switch to providing electricity when the output from wind and solar is low. On the other hand district heating systems could absorb large quantities of surplus electricity by using heat pumps to heat water which can be stored for use later.