The classic criticism of renewables is that power supply is at the mercy of nature. When the wind stops blowing and the sun stops shining generators stop generating. Thus, it would be impossible to feed a national grid with renewable energy alone – we need coal or nuclear power stations to fire up in support.
“Boo hoo” say the cynics, renewables are a waste of time.
Wrong. There is a solution.
If the wind stops blowing in the UK it will be howling off the coast of Portugal. If there is a flat calm off the coast of France, there will be lots of wave power off the coast of Scotland. There is always an abundant supply of renewable energy in the world at any given time—the challenge is making it accessible to the demand.
Enter supergrids. The idea here is to create a large-scale electricity grid across a large region like Europe or the USA that serves to supply energy from wherever it is being generated at the time, thus helping to iron out clean energy peaks and troughs across that region.
A supergrid has been proposed to link Europe, the Middle East and North Africa. This would allow electricity users to tap into geothermal electricity from Iceland, wind energy from Denmark, hydro from Norway and unleash the huge potential of solar power from the Saharan desert. And this is where the proposal really starts to gather strength.
The “TREC” international network of scientists and engineers have developed a concept called “Desertec.” In brief, this means using the technology of Concentrating Solar Power (CSP) to generate electricity in desert regions like the Sahara and transmitting the solar electricity to where it may be needed via a supergrid.
CSP works by concentrating sunlight with mirrors to create heat and then using the heat to raise steam to drive turbines and generators, just like a conventional power station. Researchers at the German Aerospace Centre (DLR) have calculated that, using CSP, less than 1% of the world's deserts could generate as much electricity as the world is now using. This sounds like a lot, but there is general agreement that the high levels of sunlight in deserts hold the key to colossal amounts of clean power.
The supergrid would be built with high-voltage direct-current (“HVDC”) transmission lines which, over long distances, transport electricity in a much more efficient way than conventional AC lines. This enables electricity to be transported thousands of miles.
So how much will it all cost? Proposals are estimating around £35 billion for the grid alone. (On the Telegraph website it claims £350 bn, this is a typo!) It’s a big number. However, when put in context, the figure is dwarfed by recent prediction by the International Energy Agency that the world needs to invest more than $22.5 trillion in energy systems over the next 30 years.
The next step for advocators is to show that this is a more worthwhile investment than its alternatives, such as developments in large scale battery power to store renewable energy.
So who’s going to pay for it? Hmmmm, this is where it gets a little more complicated.
The proposals have received applauds from Gordon Brown (although no one has asked him to get his wallet out yet) and Sarkozy (although we wonder what the French Nuclear lobby will have to say about that!). Greenpeace International has been promoting CSP for several years.
The supergrid is at its very early stages in concept. As yet, there hasn’t been enough research carried out by the critics to give them much to get their teeth into. As with anything it will come. From the outset it is hugely ambitious to engineer (although, we must confess, we do like ambitious at Green Energy Republic). Questions have been raised about the possible vulnerability to terrorist attacks, and discussion has not yet even begun on political implications between Europe and North Africa. (Europe taking resources from Africa? Now where have we heard this before…)
In all seriousness we wonder how nations will assign value to areas with highly concentrated renewable resources? Will CSP become the next oil? Supergrids will revolutionise the way renewable energy is valued and traded, and that will have to be managed very carefully to avoid political mayhem. On the positive side it has the potential to bring wealth to Saharan countries in need of an economic boost. It would certainly be interesting to see the Europe’s energy demands in the grip of Saharan nations as opposed to OPEC’s oily fingers. What if relations break down as is the case at the moment with Russia’s gas supply to Ukraine? Relying on renewables is one thing, relying on renewables from a nation Prince Philip has upset is another – “swapping” energy worldwide is going to be a delicate affair.
The debate is starting, and it’s one that needs to happen. It’s one that Green Energy Republic will be keeping an eye on. Supergrids kick start a very exciting idea - that the world could potentially be run on entirely renewable sources.
Have a read of the Desertec proposal on www.trec-uk.org.uk/index.htm and if you like it you can support the Early Day Motion 123 posted by Dr Howard Stoate MP (see http://www.trec-uk.org.uk/EDM123 ) – that should help get the debate moving.
Green Energy Republic
