I note this morning that 2,000 wind turbines are to be installed in the southern North Sea by the Irish company Airtricity and ABB, the Swedish based engineering group, which will provide 10 Gigawatts (10,000 Megawatts) of power, sufficient it is thought to supply 8 million homes. This is part of the provision of a European supergrid, linking wind farms from the Baltic Sea, the North Sea, The Irish Sea and the Mediterranean. The great advantage of this system is that essentially the wind will always be blowing somewhere, and it is proposed this will lead to constancy of supply, which is a problem with a conventional wind farm: i.e. either you put up with a very up-and-down supply - which would be no good for most electrical devices such as computers and televisions - or you store the electricity in some way, e.g. by charging batteries of some kind or more nebulously, but as some think, in the form of hydrogen produced from that electricity by the electrolysis of water.
This sounds like a fantastic idea in principle. However, if I understand the proposal correctly, providing 10 Gigawatts (GW) of full capacity wind energy by 2000 turbines means that the capacity of each is: 10 x 10*9/2000 = 5 x 10 *6, or 5 Megawatts (MW). I know that turbines rated at 2 MW exist, but I thought that 5 MW was still on the drawing board, but I guess it will take some time to approve the plan and so the technology might well have moved on by then. O.K.
Now in terms of an actual generating capacity, since turbines don't run at full capacity most of the time, if ever, we need to multiply that figure by the "capacity factor", which is reckoned on considerable Danish and German experience at a maximum of 0.2. In other words we would get 0.2 x 10 GW = 2 GW in total from the 2000 turbine farm. So each home would get 2GW/8 million = 250 watts per unit. Now this is a useful amount, and using energy efficient light bulbs it could certainly light most houses, but it couldn't boil a standard electric kettle (about 2 kW) , but it could boil a lower capacity one if you simply waited about 8 times longer.
The annual electricity consumption of a typical U.K. house is about 3500 kWh/year or about 10 kWh/day. So at 0.25 kW (250 watts), this might supply 0.25 x 24 = 6 kWh/day or 2,200 kWh/year. If we work on more energy efficient devices too, then we are not far off our requirements. I am hopeful that this might work in fact, at least for the purpose of providing a domestic supply.
The 2000 turbines are to be installed in the southern part of the North Sea between Britain, Germany and the Netherlands. The companies involved have emphasised that the construction of the power grid itself will enable free access of electricity trade between European countries, which has always been a hurdle. A cable linking the grids over 1,000 km would stretch the length of an average weather front, and so would collect wind power from each farm contained in the network, to provide a constant level of power for those countries that are linked up to the grid, and get around the "on-off" aspect intrinsic to a single farm, i.e. the peaks and troughs are averaged out to a near constant baseline value.
I think this sounds promising. However, we still need to address the problem of how to substitute for cheap oil, and the cheap fuel that we get from it, in short order. The "super-grid" does not help here, and nor is it intended to. Certainly it would help delay the problem of "Peak Gas" (which much European electricity is made from) the date of which has been revised down to about 2030 from the 2100 I heard originally.
The success of the scheme depends on it getting regulatory support and financial backing from a bank (the European Investment Bank, say) and appropriate industrial partners. I wish it well.