The problem with wind power isstorage and the problem with storage is line loss. We have forgotten that the legacy grid systemovercame both by overbuilding in the first place. It is naturally difficult to plug potentiallyintermittent energy into a power plant system that simply cannot shift loadseasily.
So we come back to a presentlyartificial allocation system that simply cannot optimize wind at all.
The real solution is about tohappen. We now have thin superconductingcable and the cost will drop quickly until it is possible to drain all the powerinto a super grid that is able to actually allocate efficiently and withnegligible line loss. All of a sudden wewill go from a national grid that uses possibly less than half of the energyproduced to one that is able to use nearly ninety percent of it.
However it is built out, and theprocess is only beginning and is not unlike the build out of the fiber opticrevolution in the early eighties that in twenty years went to overbuilt status.
During that same time period, windpower will continue on a tear as will geothermal power become hot at they bothnaturally supplant coal and nuclear with a superior product in terms of longterm impact.
Without line losses to worryabout, pumped storage comes into its own using superconducting motors to drivepumps. It becomes possible to hugelyincrease the throughput of Niagara, if one is able to pump water back up into Lake Erie .
Of course the generators therewill soon be replaced with superconducting generators increasing output byperhaps as much as thirty percent.
This shows us just how much flexibilitysuperconducting systems are bringing to the power business.
Wind power: Even worse than you thought
But your 'leccy bill will keep going up to buy more of it
By Lewis Page
A new analysis of wind energy supplied to the UK National Grid inrecent years has shown that wind farms produce significantly less electricitythan had been thought, and that they cause more problems for the Grid than hadbeen believed.
The report (28-page PDF/944 KB) was commissioned by conservationcharity the John Muir Trust and carried out by consulting engineer StuartYoung. It measured electricity actually metered as being delivered to theNational Grid.
In general it tends to be assumed that a wind farm will generate anaverage of 30 per cent of its maximum capacity over time. However the new studyshows that this is actually untrue, with the turbines measured by the Gridturning in performances which were significantly worse:
Average output from wind was 27.18% of metered capacity in 2009, 21.14%in 2010, and 24.08% between November 2008 and December 2010 inclusive.
In general, then, one should assume that a wind farm will generate nomore than 25 per cent of maximum capacity over time (and indeed this seems set to get worse as new super-large turbines come intoservice). Even over a year this will be up or down by a few per cent, makingplanning more difficult.
It gets worse, too, as wind power frequently drops to almost nothing.It tends to do this quite often just when demand is at its early-evening peak:
At each of the four highest peak demands of 2010 wind output was lowbeing respectively 4.72%, 5.51%, 2.59% and 2.51% of capacity at peak demand.
And unfortunately the average capacity over time is pulled upsignificantly by brief windy periods. Wind output is actually below 20 per centof maximum most of the time; it is below 10 per cent fully one-third of thetime. Wind power needs a lot of thermal backup running most of the time to keepthe lights on, but it also needs that backup to go away rapidly whenever thewind blows hard, or it won't deliver even 25 per cent of capacity.
Quite often windy periods come when demand is low, as in the middle ofthe night. Wind power nonetheless forces its way onto the grid, as wind-farmoperators make most of their money not from selling electricity but fromselling the renewables obligation certificates (ROCs) which they obtain forputting power onto the grid. Companies supplying power to end users in the UK
Thus when wind farmers have a lot of power they will actually pay toget it onto the grid if necessary in order to obtain the lucrative ROCs whichprovide most of their revenue, forcing all non-renewable providers out of themarket. If the wind is blowing hard and demand is low, there may nonetheless bejust too much wind electricity for the grid to use, and this may happen quiteoften:
The incidence of high wind and low demand can occur at any time ofyear. As connected wind capacity increases there will come a point when no morethermal plant can be constrained off to accommodate wind power. In theillustrated 30GW connected wind capacity model [as planned for by the UK
Want to know why your 'leccy bill is climbing, and will keep onclimbing no matter what happens to coal and gas prices? Yes - it's wind farms
Or, in other words, there is little point building more wind turbinesabove a certain point: after that stage, not only will they miss out on revenueby often being at low output when demand is high, but they will also miss outby producing unsaleable surplus electricity at times of low demand. Theeconomic case for wind – already unsupportable without the ROC scheme – willbecome even worse, and wind will require still more government support (italready often needs large amounts above and beyond ROCs).
The idea that pumped storage will be able to compensate for absent wind– meaning that there will be no need for full thermal capacity able to meetpeak demand – is also exposed as unsound. The UK UK
The John Muir analysis goes on:
The nature of wind output has been obscured by reliance on"average output" figures. Analysis of hard data from National Gridshows that wind behaves in a quite different manner from that suggested bystudy of average output derived from the Renewable Obligation Certificates(ROCs) record, or from wind speed records which in themselves are averaged. Itis clear from this analysis that wind cannot be relied upon to provide anysignificant level of generation at any defined time in the future. There is anurgent need to re-evaluate the implications of reliance on wind for anysignificant proportion of our energy requirement.
Unfortunately given all this, the ROC scheme is on an escalator: theamount of ROCs an end-use 'leccy supplier must obtain will rise to 15.4 percent of megawatt-hours supplied in 2014, up from 10.4 per cent last year. Theeffect of this is to provide the large extra funds a wind farm needs to competewith thermal generation, by driving up electricity prices for the user: The ROCscheme is a stealth tax which appears neither on the electricity bill nor theTreasury accounts.
High electricity prices worsen the case for electric transport,electric heating and electric industry, so there are reasons to dislikewindfarms even from a carbon-emissions point of view. There would be littlepoint going to partially-wind electricity if the effect is to drive people moreand more into using fossil fuels wherever possible.
But that's the way we're headed. ®
Bootnote
You can look up all the current National Grid power figures here: archives since 2008are here (registration required).
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