The idea of a wholly renewable electricity supply, using a system that spans Europe and North Africa, is gaining ground.
There is scepticism, of course, about the variability of wind and solar power, and the cost of deploying the infrastructure. But several studies in the past year have shown how a good geographic blend of sources might make this possible, and perhaps even cost-neutral – and replicable around the world. Big energy equipment vendors are forming consortiums around both the Europe-African super-grid and ‘Desertec’, the idea of a massive solar project in the Sahara desert.
One of the earliest proponents of European/North African collaboration to switch to 100 per cent renewable electricity, and the ‘super-grid’ to support it, is Gregor Czisch of Germany’s Kassel University.
Below, Czisch talks about his modelling of a transnational renewable energy system; why wind power would provide two thirds of energy in such a scenario; why renewables are better than nuclear, and how he views the reaction to his ideas, nine years later.
Your studies demonstrate the feasibility of a European electrical system supplied only by renewable sources. What are the main points of your proposal?
My proposal – derived from the results of my research – is to develop a large scale grid throughout Europe and Sahara – called super-grid – to interconnect wide spread different sites with electrical generators supplied by renewable sources, namely wind, solar, hydropower, and biomass.
In contrast with the smart grids, which represent a futuristic approach made of highly intelligent applications, the super-grid is already feasible with the technology available today, and serves to exploit in an optimal way the enormous potential of the renewable sources. [figure 1 - right]
To demonstrate this possibility, I carried out from 1997 till 2004 a technical and economical systemic study. The first preliminary publication was in 2001. I analyzed the potential and the temporal behaviour of the renewable sources in all different locations worldwide and the corresponding unitary cost of the equipment for production and transmission of renewable electricity including all costs for operation and maintenance. The data for Europe and its neighbourhood were then fed in a huge mathematical optimization to calculate the optimal distribution and dispatch of all generators and transmission systems.
The main result for the base case scenario – only allowing to use existing technologies at current market prices (around 2001) – is that the most efficient arrangement is a system where two thirds of the electrical supply are provided by wind power, which is available in all areas but with different daily and seasonal behaviours (e.g. in Northern Europe the strongest winds are in winter, while in Sahara in summer). The super-grid indeed compensates the fluctuations of electricity produced in different countries and therefore is foreseen – as a result of the optimization – to strongly interconnect the sites of production and consumption.