In the days of Queen Victoria they said, truthfully "the sun never sets on the British Empire".

But it does set on Australia, every single day. Even the green power engineers in Parliament must have noticed that the sun also sets on all those solar panels that their mandates and subsidies have plastered onto Australian roofs.

Solar energy is most intense on the equator but weakens towards the poles. It disappears when the sun sets or cloud obscures the sun. For just six hours or so per day during summer, in a clear tropical desert area, solar energy is reasonably reliable and collectible, although always very dilute. But at times of peak demand, about 6.30pm in winter, solar panels contribute nothing to electricity supply.

Billions have been spent on researching ways to store massive amounts of solar energy to cover the eighteen hours per day of low or zero solar supply.

Many things will work in the lab, even a big bank of car batteries. But once real engineers take over from green dreamers, academics and climate alarmists, most of their fanciful energy storage schemes become horrendously expensive or impractical.

But nature has provided us with the answer and some decade soon an academic will re-discover that the solar energy of yesteryear is stored in concentrated form in prodigious quantities as COAL.

So abundant, reliable and cheap is this stored sunshine, that even green Europe is rediscovering it. Seventeen coal-fired power stations are being built or modernised in Germany, the solar panel capital of the world. China, the world's biggest exporter of solar panels, is building 363 coal-fired plants for itself.

Green energy policies have destroyed the reliability and economics of power in Europe for zero benefits for the climate or the environment - reliable low cost energy is being forced out by unreliable high cost energy. Australia should have learned from Europe's solar subsidy stupidity. Subsidised solar panels may be good for harvesting votes, but they are not sensible for generating grid power. Only proper power stations will keep the lights on 24/7.

Those who wish to use solar panels should be free to do so providing they accept all the costs and benefits of their decision.