Colin R McInnes (Letters, 16
November) is to be congratulated for reminding us of the importance of Watts and Joules when thinking about power and energy.
In my opinion there should be two meters located at the gate of every wind farm, whether of hundreds or just a handful of turbines.
One would show the instantaneous power (in kW) being generated by the wind at that moment and the other the energy produced over past 24 hours (in kJ or kilowatt-hours).
This would allow the observer to calculate, for example, the number of kettles the installation would boil and thus have a better informed opinion for the costs and benefits.