The green energy revolution arrives now

 I went to Israel a few months back. One of the reasons for my trip was to investigate the Arava Power Company. Arava operates a solar farm in the Negev desert. As you can imagine, the Negev has great conditions for solar; the cost for the local utility is less than the wholesale price of the electricity from other sources. Here is their demonstration plant.

And here is the next phase of the project.

Pretty impressive, no? What, no, you say? It isn’t impressive? I guess I can see why you’d say that, considering as it is just an empty field. I have two answers for you. The first is that Arava finally started work on the new project, with the first panels installed in October; serious work got underway jointly with ET Solar and EDF this month.

So the project is underway. But that answer isn’t interesting. The interesting answer is why the company has had so much pushback against its plans to build utility-scale solar in an environment where it should be cheaper than the alternatives.

The simple answer: from the utility’s point of view, solar power is not cheap. The reason is intermittancy. Not just intermittancy in the sense of the sun not shining at night, but intermittancy in the sense that passing clouds (and even the Negev has passing clouds) can cause output to drop 95% in a matter of minutes. That means that the utility needs to keep gas plants ready — and on days with the risk of clouds those plants will need to be spun up and burning fuel in order to start generating quickly.

The Israeli government has been abetting the utilities, holding up permits and unpredictably altering the feed-in tariff for solar. Arava officials told me that the government also weirdly decided to raise the land rent (land in Israel is state-owned) on solar farms. (The link is worth clicking; it corroborates what the Arava people told me.) Solar in Israel is moving, but not that fast.

But now from California comes news that could change everything. 

Cheap storage would, of course, utterly transform the economics of renewable energy. Intermittancy would no longer be that important. Even at a small scale, it would be worth it: no more worries about passing clouds. And on a large scale, of course, cheap storage would no longer matter that the sun doesn’t shine at night.

So what happened in California? It wasn’t a technical breakthrough; those are always being announced. Nope, it was that storage won bids put out by Southern California Edison for new capacity in the wake of the decision to close the San Onofre nuclear plants.

That is big news! If storage really has become competitive with peaker plants, then the door is open to an entirely new energy landscape ... as long as storage continues to fall in price. Keep an eye out.

Comments

[David Allen]

Do you know (and/or can you say) whether the type of storage will be chemical batteries or something mechanical?

[Noel Maurer]

Sure! Most of 'em are lithium-ion batteries. (RES, for example, delivers systems that can supply 19.8 MW and store 7.8 MW-hours.)

But there are also the Ice Bears! These things basically use energy to freeze giant ice cubes on rooftops. The ice is then used to chill interior spaces the next day. How cool is that? :-)

[David Miller]

Professor Maurer,

A 95% output drop does not pass the sniff test for the 40 MW solar facility ET Solar and EDF are building. See Figures 5 and 6 of this paper by Sandia National Labs:

http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=6744495&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D6744495

A 40 MW facility in Puerto Rico would almost never have output drops of more than 40% within minutes. In San Diego, the result would have an even lower probability of occurrence. My guess is that the Negev is not so different.

A 95% drop is more reasonable for a small residential solar array, but the output drop from a small array is unlikely to cause voltage problems on the grid. In contrast, multi-MW solar facilities exhibit significant benefits from geographic diversity. This is all the more true as as central inverters get replaced by string inverters and microinverters for utility-scale solar.

Lest you think this is propaganda from the pro-solar lobby, I speak representing an energy storage company that benefits from solar's problems. My company, http://www.greensmithenergy.com , builds software controls for energy storage, including storage devices designed for solar ramp rate control. We are also the technology partner for one of the winners of the SCE storage procurement. The energy storage hype cycle continues to pick up speed!

David Miller
The Energy Business and Geopolitics, Fall 2012

[Noel Maurer]

Thank you, David! I wish I got more comments like this.

The 95% figure, not surprisingly, was passed to me by an official of the Israel Electric Corporation. I need to do more due diligence ...

I hope it's not a storage hype cycle! As you know, good cheap storage really does change everything. Your company looks fascinating, by the way. Congratulations!

[David Miller]

Thank you! And I should not be so flippant in my comments. I too am excited for the wide-scale deployment of energy storage!

[Doug Muir]

Here in Germany, some interesting options for storing windpower are being explored. One is using windpower to pump water. This is site-specific, so it has limited applications, but it lets windpower be stored indefinitely as potential energy.

Another is useing windpower to crack hydrogen out of water. The hydrogen can then be used to turn turbines at off-peak, or it can be injected directly into natural gas lines. It turns out that spiking natural gas with a few percent by volume of H2 works great -- and some natural gas is saved, thereby slightly but noticeably reducing reliance on expensive (and mostly Russian) gas imports, and you also cut your greenhouse emissions by a little.

The good news: There are already several hydrogen-producing windmills, including a 2 MW pilot project that's putting H2 into natural gas lines in the former East Germany. And it looks like this will be a money-making proposition.

The less good news: efficiency is not high; we're talking maybe 25% on a good day. Also, scaling up will be a challenge. Burning H2 directly requires expensive specialized equipment. Putting it into the gas lines is much cheaper and simpler, but it only works up to a point. That's because once the proportion of H2 exceeds 10% or so, normal equipment can no longer handle the mix -- hydrogen starts to leak out of the system, ignition and combustion temperatures change, and so forth.

Doug M.

[David Allen]

Yes, very cool. (groan.)

[Chris Williams]

Doug, I can see that there's no point in re-plumbing domestic gas appliances to handle pure H2, or more than 10% 'spiked'. Are there many industrial users of gas who could invest in an alternative H2 system to sit alongside their natural gas system?

[Doug Muir]

Chris, that's a good question and I don't know the answer. My tentative guess, though, would be that H2 from windpower is never going to be that big -- when you convert windpower to hydrogen, you're throwing away ~3/4 of the energy. That only makes sense if it was waste energy to begin with.

Which can certainly happen! For instance, if the wind is blowing hard all over the country, the sun is shining brightly at the same time, and/or you're at an off-peak time when demand is low. But it shouldn't happen *too* often, or you're not going to make much money off that particular windpower site.

So, since the hydrogen thing is going to be a relatively minor by-product, building industrial infrastructure around it is probably not in the cards. But using it to reduce natural gas consumption by a few percent? Hey, that's money you're not mailing to Vladimir Putin. Win-win.

Doug M.