includes the line 'And it will only be 45 per cent efficient, in an age when power stations can reach 95 per cent efficiency'.
This is a coal-fired power station, so 45% efficiency in converting thermal to electrical energy is I think extremely good.
95% thermal efficiency implies, by the Carnot equation, that the heater is twenty times hotter in Kelvin than the heatsink and that there are no other thermal losses in the system. With a heatsink laid on an infinite icefield at zero centigrade, the heater has only to be hot enough to boil tungsten. I was unaware that gas-cored fission reactors were either in production, or this enthusiastically endorsed by Greenpeace.