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Divided French reactions to 1,000 km of solar roads

Journalist Olivier Daniélo is not happy about French Environmental Minister Royal’s plans for a megameter of PV. Today, we review his collection of French and other voices and analyses.

Few issues draw as much attention as alleged “breakthroughs” with renewables. The public wants a tech fix and cannot be faulted for lacking the technical expertise to realize that we already have it; German experts have come up with a slew of scenarios for 2050 for a high share of renewable energy, and none of them require anything we don’t have today. Journalists need breakthrough stories for clicks, and reporting that today’s solar panels and wind turbines are going to get the job done isn’t sexy somehow. The downside is the misimpression this skewed focus leaves that the tech we have is insufficient. It ain’t.

I have already listed the reasons why solar roads are bad, so I will only repeat my bumper sticker slogan here: put solar on stuff, not stuff on solar. But why does Ségolène Royal not get it? Granted, she is a lawyer by training, so she may not understand the physics of PV herself – but she is also surrounded by France’s top thinkers. How do such an obviously bad idea get through as national policy?

Over at DD Magazine, Daniélo (his Twitter account) has written a scathing piece on his country’s plans for solar roads. He collects various voices who say it’s a bad idea, including Stanford’s Mark Jacobson, who says “this seems like a very inefficient use of scarce funds,” and French expert Yannick Règnier of CLER (Network for the Energy Transition), who also calls the plan “a bad idea.” The problem is partly the cost. According to French road construction giant Colas quoted in Daniélo’s article, French solar roads will cost around six euros per watt, roughly 6 times the cost of normal solar panels.

They will also produce far less electricity. French engineer Nicolas Ott says that the energy payback from boring old crystalline solar panels – the ones that silently produce increasingly competitive electricity without emissions from your otherwise unused rooftop, yawn – is around 7.5 to 1, meaning that the panels produce 7.5 times more energy than is used to manufacture them. In contrast, the Wattway system, as it is called, as an energy payback of 1.6 to 1.

The post on Danièlo’s personal blog is even more interesting. He quotes another French expert saying essentially that Ott’s calculation is generous. His anonymous expert believes the panels could be energy losers in practice; more energy might be needed to make them than they ever produce.

It is still hard to calculate the cost of the electricity from these numbers, but one French expert I spoke with, who wishes to remain anonymous, says that Colas is likely to get the contract to build these solar roads, so it will not protest to loudly – and this is where we begin to find an answer to why France is pursuing such a bad idea. There’s something in it for practically everyone who should oppose it.

As Daniélo points out, Colas received a “climate solution trophy” at COP21 for Wattway. He also quotes a number of statements indicating that the project is partly an attempt to give business to struggling French PV firm Photowatt. The only reason why other companies might also receive contracts, Daniélo explains, is because Photowatt currently only has a production capacity of 90 MW annually, which may not be enough for the project.

We still lack a lot of details, but Daniélo does some basic math to produce some ballpark figures: 1,000 kilometers of roads with 3.5 meters of panels side to side and 130 watts per square meter would produce 455 MW of installed capacity over the next five years – ironically, exactly the output of Photowatt during that timeframe. But given the lack of thinking in other aspects of the project, I doubt anyone did the math on this – it’s probably coincidence. But the number also allows Daniélo to calculate the cost, roughly: “2.7 billion euros for 445 MW with a capacity factor less than 10 percent.”

It’s an absolutely dreadful outcome, he points out, adding that it only seems competitive compared to the new nuclear reactor being built at Flamanville, which may have skewed French leaders’ thinking.

Above, we focus solely on the reasons why this is bad PV. We haven’t even gotten to the reason why these will also be bad roads. Daniélo cites a slew of French road experts expressing their skepticism. Or, if you don’t speak French, you can just visit my old post on this matter and click on the video linked to.

The only way out of this dilemma – and the project must be stopped, for the PV sector will have hell to pay the more Wattway goes forward – is to start depicting our conventional solar panels and wind turbines for the fantastic breakthroughs they are. PV is getting so cheap that we are now talking about “storage parity.” And modern wind turbines are now taller than medieval cathedrals. Even though they have dozens of tons of metal (the equivalent of dozens of 18-wheelers) at the top, wind turbines withstand bad weather even better than conventional thermal plants on the ground. And if you think they are loud, you should try to record them. This technology isn’t boring; it’s magical.

If you speak French and would like to hear Royal’s enthusiastic presentation of the project, listen to this radio show.

(Craig Morris / @PPchef)