DESERTEC-Australia thinks solar energy, particularly CSP, is a feasible and affordable source for Australia’s future energy needs. All we need to do is spend a few billion on transmission lines to the desert. Plausible enough. But their long-term plans are just a teeny little bit more ambitious, if you read on.

There’s been a lot of speculation that Europe could get much of its electricity from solar power in the Sahara, with some long-distance power lines across the Mediterranean. Ambitious, but plausible, given the proximity. Heck, it’s only 13 kilometres across the Strait of Gibraltar. Australia has similarly attractive solar resources. But where in the heck would we send them. Well, how about where we currently send our coal… – yep, Asia, and, particularly China! Yep, if you read on far enough, they’re proposing a variety of different cable routes all the way to Singapore or even directly to China. The projected price tag for this engineering masterpiece? 500 billion dollars.

The most appealing thing about this idea is that the technology exists, in principle. High-voltage direct-current transmission is already used to send electricity surprisingly long distances with acceptable levels of line loss. Undersea electricity cables are also becoming more and more routine. This cable, between the Netherlands and Norway, runs 780 kilometres under the North Sea. Scale it up in length by roughly a factor of 10, and multiply the capacity by a couple of orders of magnitude, and you’re there! Easy…

As a sort-of engineer whose Dad spent time working on the Snowy Mountains scheme in his youth, this kind of thing has its appeal. But I can’t see how it can be viable. Aside from the gargantuan scale of the project – which can’t be easily split up into digestible chunks – this would be centralization of infrastructure on such a scale that the arguments about reliability and security of supply actually start to make sense. Not to mention that you’d have to wonder how the economics of the proposal compares to building CSP plants in China’s desert areas. They may have poorer solar insolation, but the construction costs should be lower and the transmission line infrastructure required would be a tad less ambitious.

But it’s a heck of a thought experiment, if nothing else.