What is the single most pressing issue in the debate about decarbonising heat?

The simplest questions are usually the best. By many measures, heating accounts for around half our total energy use. The cost of that energy has gone up significantly in recent years. Less than 5% of our heating is from renewable sources.

We all know the problem, how to get the first two of these measures down and the third one up. So here's where the simple question comes. What is the one thing we should focus on?

It would be tempting to use this opportunity to lobby on the political environment and support mechanisms or to wax lyrically on new technologies but I don't believe that either of these important areas are the one big thing. So what is it? I believe it’s Behaviour. 

Let me explain. The reason why we don't insulate our homes or set our thermostats and time clocks correctly is behavioural or to put in bluntly, we can't be bothered.  The reason why district heating is so hard to get going in the UK is because we all want our own boilers in the corner of our house. The reason that biomethane struggles to make inroads is that we don't regard organic waste as a valuable fuel and just throw it away. The reason we don't install new technology such as heat pumps is because the old ways are easier. 

We don't need more engineers and lobbyists taking part in the heat debate we need behavioural economists, anthropologists, psychologists and sociologists to work out how to get us off our backsides and actually do something.