If Scott Morrison had wanted to demonstrate his energy agnosticism when he waved a lump of coal around in Parliament he would also have waved a lump of silicon.
Assuming each weighed one kilo, he could have explained that the coal, when burnt in a power station, would produce nearly 2.5 kilowatt-hours of electricity, about 2.5 kilos of carbon dioxide, up to seven grams each of sulphur dioxide and various oxides of nitrogen, about 50 grams of fly ash, a few micrograms of heavy metals, including mercury, and some radioactive waste.
Then, holding up his piece of silicon, he could have said: «This could make a bit over two square metres of solar cells. As most of Australia gets at least five hours of full sun a day, which is about a thousand watts per square metre, this means the silicon, at 20 per cent efficiency, would generate in one day about as much electricity as my piece of coal.»
Then he could have told Parliament that the silicon cells were guaranteed for 30 years, during which they would generate over 20,000kWh, or 10,000 times as much electricity as his piece of coal.