Geoffrey Lean notes that:
Within two decades Denmark could get all of its electricity from renewable sources
And then goes on to tell us how it\’s all amazing and to do with the wind.
Then at the end we see the kicker:
More fundamentally, the wind – as critics often point out – does not blow all the time. That is not too much of a problem when there is not much wind power, but it becomes really serious when you are as dependent as Denmark, whose turbines can go from generating 3,100 megawatts (the same as three big power stations) to absolutely nothing in just a few hours.
The problem was solved by linking up with Norway, which has plenty of hydroelectric power – which, unlike the wind, can be stored. When the gales are blowing in Denmark, it supplies electricity to Norway, which turns off the generators in its dams. When the wind drops, the Norwegians let more water flow, to help their Danish neighbours.
Such a system, experts increasingly say, may allow Britain – which has more suitable winds than Denmark – greatly to expand its offshore wind capabilities, too.
The kicker being of course that there ain\’t enough hydro power in the whole of Europe to power the UK (note well that Norway and Denmark are both about 5 million people each). Which means that we cannot rely upon such a system.
We would need back up generation of some other kind. And for back up generation it really has to be natural gas turbines as these are the only things you can turn on and off fast enough.
We could, it is true, go for wave or tidal power. But if we installed enough of that to provide the power we would need when the wind wasn\’t blowing (and it would have to be enough to power peak demand, for we have indeed seen that those frosty winter days when demand is at its peak are those when the entire country is bereft of wind) then we wouldn\’t need to install the windmills at all.
Which leads to, either a double generation system, gas and wind, or no wind at all. Which really isn\’t quite the same as the wondrous stories we\’re told about what wind can do for us.