Clean energy advocates think we can use the batteries in an electrified road transport system to balance the supply of intermittent renewable electricity with the demand for electricity, including electrified heat and transport. They are wrong. It can work to a small extent, but it barely touches the sides of the problem.

Labour's energy and climate-change proposals in their 2019 manifesto are vastly more expensive than they recognise - probably £1bn by 2030 and £1.5-2bn ASAP in the 2030s. This spending would reduce carbon emissions by less than 50% by 2030. One unintended consequence is that, despite so much infrastructure spending, electricity supply would occasionally be insufficient to meet the radically increased demand.

Efforts to encourage renewable electricity and renewable transport do not have much effect on the overall levels of renewable energy. It is the levels of renewable heat that most strongly influence the overall delivery of renewable energy.