Kicking Oil Addiction: Europe Looks At Sahara Sun

Turn the Sahara desert into one giant solar/wind farm....

Substitute the Sahara with a good portion of the Southwestern US, and voila, clean energy for Americans.

Construction costs alone would be high, and that's before you build all that transmission infrastructure. You know, the infrastructure that already is known to be deficient, and the new construction of which is fought by the NIMBYs (who force California to get electricity from outside the state). Did you forget about that? None of that is free (and some of the materials used are not clean).

No, the southwestern USA is not the answer to the US's problems today.

For those who didn't do their homework earlier:

http://www.phyast.pitt.edu/~blc/book/chapter14....

Amanda,

The material to which I just posted a link (a chapter in a book by Cohen, who is in the nuclear community) is dated but is definitely worth your reading.

Also what you need to know is that the transmission infrastructure is commonly a thing that is overlooked by many proponents of alternative energy and this needs to be addressed. Note that construction of transmission facilities involves Evil Industry and there is significant anti-transmission-line activism wherever any substantial project is proposed.

For the record, while I don't find wind farms (or solar farms) to be "majestic" as Evil Bird Killer [tm] wind fan Chris WWW does, I don't find them eyesores; they interest me when they are found where otherwise we would face monotony. (This is true for offshore facilities as well as desert or Plains facilities; this is also true for oil rigs, not just wind towers or solar collection and distribution arrays.)

By all means, support some research into even off-grid things like solar cells on roofs in the Southwest to help meet air conditioning costs, as well as basic R&D on boosting efficiency of the collection devices (and of wind turbines), but don't neglect the transmission facilities to get the solar (and wind) onto the grid and realize that it's impractical to expect to exploit the Southwest solar regime and send the power over snazzy ultra-high-voltage DC lines to the rest of the country, especially at nighttime.

Also, for those of you who know your history, the Congo Lake concept (much larger than the Qattara Depression) makes more sense than using the Sahara insofar as reliable, clean, cheap electricity is concerned.

Amanda, FYI.


http://envirovaluation.org/index.php/2008/07/01...

DLS: The material to which I just posted a link (a chapter in a book by Cohen, who is in the nuclear community) is dated but is definitely worth your reading.

Boy, I'll say it's dated -- it was written in 1990, for goodness sake! The data presented are two decades old!!

However, you are correct about the need for transmission lines, and that probably is something many proponents of wind and solar (mostly solar thermal) don't appreciate. In order for those types of renewables, an extensive, integrated transmission network is required. And yes, transmission lines are expensive, and in some cases controversial. IMO, they should be controversial. They shouldn't be strung willy nilly just anywhere. Then again, everything is controversial to somebody somewhere.

So, how expensive are transmission lines? Well, this article discusses a major transmission project just approved in Texas (I see you are already aware of it). It will cost an estimated $4.93 billion and will be able to deliver up to 18.5 GW of power to population centers all around the state. That works out to about $267 thousand per GW. By comparison, a pair of proposed nuclear plants in Florida (with a capacity of 2.2 Gw) are expected to cost $17 billion, of which $3 billion is transmission lines. Thats $1.15 billion per GW. Big difference.

Furthermore, this study by the DOE estimates that converting 20% of the national grid to wind by 2030 (including the necessary transmission network) would cost rate-payers about $0.50/mo per household more than now. They also mention this: Construction and grid integration of large-scale nuclear and coal plants in the 1960s and 1970s entailed installing companion high-voltage interstate transmission lines, which were needed to deliver the new generation to loads. Even the natural gas plants of the 1990s, although requiring less new electric transmission, relied on expansion of the interstate gas transportation network. Significant expansion of the transmission grid will be required under any future electric industry scenario. Expanded transmission will increase reliability, reduce costly congestion and line losses, and supply access to low-cost remote resources, including renewables.

Any expansion of solar thermal is likely to be similar in terms of transmission requirements. You mentioned HVDC transmission. If very long distance transmission is contemplated, that would certainly be the way to go -- because it's cheaper than HVAC at longer distances. According to this analysis, the break-even distance is around 500-800 km (300-500 mi).

One more thing, DLS... you mention that solar doesn't work after dark. While that's true for solar PV, most of the new solar thermal plants being proposed or constructed include some form of heat storage (usually molten salt), allowing them to operate well after dark. One company, Ausra (www.ausra.com) claims it has a storage method that can store heat for up to 16 hours. I guess we'll see soon.

I should also mention that one of the very appealing aspects of solar power is that it's most efficient during the time of day when power demand is highest. Currently you have to either overbuild baseload capacity so that it can handle peak loads or (more commonly) fire up a "peaker" plant to handle peak load. Peaker plants are usually gas or diesel driven, because they are about the only ones that can be fired up quickly. They are also the most expensive. So when comparing costs, those are the ones that should be compared to solar. Nonetheless, many in the solar industry are reasonably confident they can get their costs down far enough that they will be able to compete with coal within a decade -- assuming enough of them get a chance to be deployed in the mean time. And that will require a certain amount of support (e.g., extending the investment tax credit).

You mentioned that many supporters of renewable energy don't consider transmission issues. I'd say that's true. But as I stated in my previous comment, those issues aren't entirely unique to renewable energy. It's also my impression that many of those that don't support renewable energy, or prefer nuclear to other technologies, do so because they think the other technologires are way too expensive, or not ready for prime time. The fact is, they aren't expensive when compared to nuclear. They are already fairly comparable now, and the costs are trending down rather than dramatically up, as is the case with nuclear.

As far as "ready for primetime" goes, wind obviously is. Solar thermal is quickly getting there. Maybe not in this country, but elsewhere. Solar PVs are. They are just more expensive at present. But I suspect that is about to change. There have been too many encouraging developments to discount it. Besides, "rooftop" (end user) PVs only have to compete with retail electricity prices (peak retail at that), not wholesale.

"Boy, I'll say it's dated"

Yes, it is dated. However, wind and solar still aren't replacements for nuclear or hydro (the two cleanest energy supplies) or fossil fuel plants because they are intermittent. Also, sometimes dated materials, when they address concepts which aren't rapidly dated, are better than up-to-date tech-cluttered and jargon-cluttered materials.

What matters more here than the latest nuclear designs (which I've addressed elsewhere) and which deal with what's largely dated material to which I posted the latest link, is that independent of any shrieking by environmentalists and activists, there has been slow, quiet progress, substantial progress, as this less-dated report may reveal to you, with wind power. It's an awfully glowing report, I'd say.

http://www1.eere.energy.gov/windandhydro/pdfs/4...

* * *

"I should also mention that one of the very appealing aspects of solar power is that it's most efficient during the time of day when power demand is highest. "

Yes, peak load. And that's particularly useful in the Sunbelt on hot summer days. I'm enamored of the true "green roof" concept -- I've lived in the East in the world's greatest deciduous forest for several years now and it's made me something of a naturalist. (I'm attuned to many details -- the end of spring and introduction of summer represented by the wildflowers everywhere is in full force and now summer has truly arrived, because the "Yellow and Black Attack" of black-eyed Susans throughout eastern NortH America is now in full force. Summer is here.) I'm tickled by the idea of true "green roofs" that feature deciduous trees or fruit or vegetable gardens on the roofs of buildings in urban areas (other plants the young might be tempted to grow are illegal to grow, sadly, even if they are delightfully fragrant as well as offering other benefits). But an alternative that I have mentioned before would be roofs filled with solar panels, to provide a small but meaningful amount of "off-grid" power to the buildings mounting these panels.

(How to grow plants safely on roofs, including trees? Use plenty of perlite! It's good for growing plants in addition to being light weight and a good insulator as well.)

"heat storage (usually molten salt)"

It's suggested for some kinds of nuclear reactors because of its heat capacity and why not try it for solar as well? It's the compliment to Chemical #1 I'd be amused to learn about being put on terrorist territory -- the compliment being, of course, NaK. You likely already know about its heat capacity if not the air and water reactivity and other many hazards it (accidentally or intentionally) can present to people and things. Less snazzy stuff still works, sodium only as a liquid metal alternative.

"'rooftop' (end user) PVs"

Off-grid. Not a substitute year-round for fuel cells someday (with vehicles as well as with buildings), but solar is intriguing these days.

"[transmission] issues aren't entirely unique to renewable energy"

Acknowledged and understood.

I had a note come my way from a friend in Upstate New York, where people he knew who never would think of engaging in silly or embarrassing activism had changed their mind and are actively (as in being activists) opposed to this:


http://www.nyri.us/

DLS: However, wind and solar still aren't replacements for nuclear or hydro (the two cleanest energy supplies) or fossil fuel plants because they are intermittent.

That's where a wide area interconnected transmission grid comes in. I linked to a DOE study in my previous comment. You should read it. They talk about how the intermittency of wind isn't very intermittent when it's distributed widely enough. In other words, it's not calm everywhere all at once. Thus, a distributed grid with a large input from wind can act as a baseload source as well as one totally powered by any combination of coal, hydro, and/or nuclear. By the way, the Europeans are coming to that conclusion as well.

Likewise, it's not cloudy everywhere all at once either -- especially in the deserts of the Southwest. If you're interested in learning how a solar-based distributed network might perform, this is a good source.

I don' t know what you've heard, but the molten salts used in solar thermal plants are usually (I say "usually" because I can't conclusively say "exclusively") Na or K compounds. Usually nitrates. Okay sure, potassium nitrate could be used to make black powder or "fertlizer bombs". But the compounds by themselves aren't explosive. And I doubt a terrorist would go to the trouble of knocking over a solar power plant when they can get the stuff far more easily by other means. The compounds are also non-toxic. They are corrosive however, especially at the high heats they operate in. So yeah, you have to be careful. Then again, you have to be careful about a lot of things. Nuclear is a very good example. So I really don't know where you're going with your argument. I'm not even sure you're arguing! Lol! But your comments do strongly remind me of others I've encountered that consider renewables like wind, solar, etc., as somehow inadequate. And to be honest, I thought they were too -- until I started to study them more closely. What they are are different than fossil fuels. So if you apply the same sort of thinking to them that are currently applied to fossil fuel sources, of course they're going to look inadequate -- and therefore prohibitively expensive. They require different thinking -- different thinking with regard to infrastructure requirements, different thinking with regard to regulatory policy. Different thinking with regard to financing.

And you're right, many of the necessary shifts in thinking (and consequent practice) are already happening. They are happening because states, either individually or in various aggregates, are acting on their own because there isn't any coherent policy on the federal level. At some point, however, and as the EU is learning, there will have to be a coherent, broader based (which means a federal level -- or even North American level) policy to tie everything together. Otherwise, inefficiency, fragmentation, and internecine court battles are the inevitable result. And that doesn't help anyone.

By the way, I grew up in the northeast. I was a Connecticut yankee. You might say that was both literally and figuratively true -- I worshipped the Yankees when I was a kid. Lol!

One more thing, DLS: why are your friend's friends opposed to NYRI?