Figures compiled by the BP Energy Review show that solar power provides less than 1 per cent of the world’s electricity and barely 0.3 per cent of all its energy. Most of this, thanks to the subsidies available in the climate-change-obsessed EU, comes from Europe.

But, despite all the billions poured into this “solar boom”, not its least startling feature is the regularity with which the companies investing in it go bust. One of the first, in 2011, despite being given more than half a billion dollars by President Obama, was a US firm Solyndra.

This was followed in 2013 by the collapse of Solar Trust of America, given a $2.1 billion loan guarantee by the Obama administration to build the largest solar farm in the world in California. Last March, the collapse of Europe’s largest solar company, Abengoa, after building two billion-dollar solar farms in the US, was the largest bankruptcy in Spanish history. Another giant US firm, Sun Edison, last year valued at $10 billion, has seen its shares fall from $33.44 last July to barely a cent.