Subversion

Our son is a carpenter/builder with a strong bias towards sustainable techniques and materials. When his ancient white van went to the scrapyard in the sky earlier this year, he got a new (to him), bigger one. In line with his business ethos, it is 100% electric. It is outside now, charging the battery. I casually asked what the capacity is: 75 kilowatt-hours (kWh) 

That's somewhat more than many electric cars (the van is made to carry a significant load), but only by 10 or 20%. It is the first time it has really hit me how big the energy capacity of electric vehicles is. In the three summer months this year, the electricity consumed by our entire house was around the same number. Even in the dead of winter, 75kWh is more than a week's supply

It's possible to use a car's batteries as a source of power for the house. In combination with PV panels on the roof, spare power generated by the panels can be stored in the car, then fed back to the house when the sun is not shining. Similarly, it's possible to take cheap electricity from the grid in the early morning, store it in the car, and and use it when electricity is expensive in late afternoon and early evening. Food for thought

So, our family are gathered and the days has passed with joy and laughter, not least at this sign