Is there anybody who isn’t squabbling over solar power? Beijing does not like European subsidies while Brussels has already queried China’s solar cell pricing and brought a case against Canada. Washington has levied anti-dumping tariffs against Beijing. Enough. All the subsidies in the world have not produced a viable industry. But technology might be about to do so.

Solar power has been an investment black hole. In five years, the combined market capitalisation of the biggest groups has shrunk by about nine-tenths. And that includes survivor bias, since many companies have already flamed out. If there was something to get wrong, the industry has done it – from overcapacity to reliance on government subsidies in an age of austerity. Yet the cost per watt of installing solar facilities has also fallen by four-fifths over those five years, according to Bernstein. Now roughly $1.23, the cost could fall below $1 next year, the firm estimates. That would make it potentially cheaper than gas in the sunnier parts of China, the market with the biggest potential. It will still be 50 per cent more pricey than coal, from which China takes most of its energy but which it wants to reduce. Solar power could help without relying on subsidies.

Getting the economics of solar power to a point where it makes sense is one thing. Picking a winner among those still standing is another given the value destruction. Net debt is often equivalent to more than half of solar-panel makers’ total capital. Suntech, the world’s biggest solar panel manufacturer, risks being delisted in New York. Thinking that the industry can stand without subsidies in the near future is a mistake. However, it will not be the trade battles currently under way that make it work, but the technology. This is getting interesting, but it would take a very brave investor to jump in just yet.