Solar Power Aims for Base Load Status

[a_unique_person]

http://www.abc.net.au/news/stories/2007/10/02/2048420.htm



Two of America's biggest power utilities have unveiled plans for a multi-billion-dollar expansion of solar power supply, backing the argument that solar energy can indeed become a viable alternative to coal-fired electricity.
The company at the heart of the development is Ausra. It was started by Australian solar expert David Mills, who left this country for California earlier this year to pursue the further development of his ground-breaking work.
What makes the announcement more significant is that the utilities are confidently predicting that their solar power will soon be providing baseload electricity - that is, day and night - at prices competitive with coal.
Those associated with the project believe it could signal a paradigm shift in electricity generation.
After decades as a fringe player in the energy industry, solar power is finally taking off in the world's largest economy.
Dr Mills says solar power could potentially supply most of the world's electricity.





Not that I think it needs to, as a decentralised power system that doesn't rely on central baseload power stations could still be viable. However, that seems to be the model we are running with at the moment.

I'm guessing a gigawatt power station is going to be huge.

[Zep]

Perhaps if they started to mix-and-match generation facilities then they would not find themselves snookered investing in a method that uses finite, diminishing resources.

For example, wherever sensible, use wind, ocean waves and tides, sunlight, geothermal, hydro-electric, etc, or any mix. Australia, like California and most subtropical locations, has huge areas suitable for solar power generation. Various coasts of the world have huge tidal flows worth tapping. Geothermal is easily accessible and nearly free. Etc, etc.

What is REALLY needed is an efficient energy storage/release mechanism. Almost all generation methods now and projected suffer from the "use it now or lose it" syndrome. If this can be conquered soon, the advent of locality-suitable renewable power generation will boom.

[Dymanic]

What is REALLY needed is an efficient energy storage/release mechanism. Almost all generation methods now and projected suffer from the "use it now or lose it" syndrome.

Dr Mills says:

"There is a convenient correlation between humans' power consumption and the sun's power supply. We get up in the morning everyday, we start using energy, we go to sleep at night. And that correlation means that we can get away with a lot less storage than we might have thought."

[mhaze]

Dr Mills says:

"There is a convenient correlation between humans' power consumption and the sun's power supply. We get up in the morning everyday, we start using energy, we go to sleep at night. And that correlation means that we can get away with a lot less storage than we might have thought."

Exactly the rationale for daylight savings time.

Oops... daylight savings time didn't work out too well.

[Dymanic]

Exactly the rationale for daylight savings time.

Oops... daylight savings time didn't work out too well.
In what way?

[Soapy Sam]

What is REALLY needed is an efficient energy storage/release mechanism. Almost all generation methods now and projected suffer from the "use it now or lose it" syndrome. If this can be conquered soon, the advent of locality-suitable renewable power generation will boom.


Clockwork.

[genesplicer]

What is REALLY needed is an efficient energy storage/release mechanism. Almost all generation methods now and projected suffer from the "use it now or lose it" syndrome. If this can be conquered soon, the advent of locality-suitable renewable power generation will boom.

I've always wondered if it would be possible to build enormous capacitors to store the energy. Is there a reason that you can't build capacitors the size of school buses to store a charge and then release it to the grid? Perhaps the cost would be prohibitive or the heat loss would be too much to be worthwhile, but I don't know.

[GodMark2]

I've always wondered if it would be possible to build enormous capacitors to store the energy. Is there a reason that you can't build capacitors the size of school buses to store a charge and then release it to the grid? Perhaps the cost would be prohibitive or the heat loss would be too much to be worthwhile, but I don't know.

Short answer: We'd need something bigger than a bus. A lot bigger.

A typical energy storage system is in use across the world for computers: the UPS (interruptible power supply).

An example from Tripp Lite (http://www.tripplite.com/products/product.cfm?productID=2)

Tripp Lite's BCPERS300 standby UPS system offers surge suppression and long lasting battery support for personal computers, internetworking equipment and other sensitive electronics. Internal UPS circuits support entry level PC systems for up to 15 minutes during power failures and brownouts so that connected equipment can be shutdown without data loss.

It can power one 'entry level' (read: not very powerful, max 175W) business computer for about 15 minutes. And it's about half the size of the computer itself (8.5" x 4.25" x 5.5").

So to power a city full of computers (and nothing else) we'd need half as much size as the computers themselves take. And that doesn't even try to run a refrigerator(1,000 watts) or heater(1,500 watts), just a lowly 175W computer (not even it's monitor). Or three typical light bulbs (60 watts each).

We'd need a BIG capacitor (or battery) for that sort of load.

[genesplicer]

So, if energy storage moves along the lines of data storage, we may have something feasible in the near future. Think about hard drives and flash drives and how they compare to 20 years ago. Then think about where batteries were 20 years ago. We are making progress. Maybe in 50 years we'll have to problem beat...

[GodMark2]

So, if energy storage moves along the lines of data storage, we may have something feasible in the near future. Think about hard drives and flash drives and how they compare to 20 years ago. Then think about where batteries were 20 years ago. We are making progress. Maybe in 50 years we'll have to problem beat...

We are making progress in energy storage, but nowhere near what the progress in data storage has been. After all, electronic data storage is about half a century old, whereas rechargeable battery storage has been around for a century and a half. Capacitors for two and a half. Most of the improvement in almost any technology is in the first century. We are making improvements in energy storage, but don't expect it to be like data storage has been for the last decade. (For that matter, don't expect data storage to increase in the next decade like it did in the last.)

[tracer]

For energy storage, I'd bet my money on an electrolysis/fuel-cell combination. Store the energy as molecular hydrogen!

[Graham Jackman]

I've always wondered if it would be possible to build enormous capacitors to store the energy. Is there a reason that you can't build capacitors the size of school buses to store a charge and then release it to the grid? Perhaps the cost would be prohibitive or the heat loss would be too much to be worthwhile, but I don't know.

The problem with capacitors is that half the energy used to charge them is dissipated as heat in the internal resistance. Secondly, the voltage falls as you remove their charge, which is much less convenient than a battery.

[mhaze]

Why don't factories making solar cells power themselves just with solar cells?

[Zep]

Clockwork.:D

[Michael Redman]

I think transmission is a bigger problem than storage. You can charge all the batteries you want at your solar station out in the unpopulated desert (i.e. Australia), but what good will they do you there?

Efficient transmission could also deal with the day/night problem, as we could build a world-wide grid to move energy around from the day side to the dark. Orbital solar would be even better, but, again, transmission is a huge problem.

[Schneibster]

Actually, a company in Texas called EEStor has a contract to make ultracapacitors with a storage density of 1 MJ/kg. This is impressive, since Li-ion has a density of only 0.5 MJ/kg. Their contractee is ZENN Motors, who propose to make electric cars with them. EEStor was funded in April by Kleiner, Perkins, Caulfield, and Byers. Prominent KPCB clients include Google, Amazon, Sun, AOL, Compaq, Genentech, Netscape, and many others that are household names today. The president of EEStore comes out of hard drive manufacturing, where he probably learned a great deal about depositing thin films onto various surfaces; this is essential technology for supercapacitors. Maxwell is also working on supercapacitors of a different design, and has ones that will outperform most lead-acid batteries already available and shipping, although their cost compared to lead-acid batteries is prohibitive so far.

[Dan O.]

For mobil applications, the energy density is most important. For fixed applications, it the conversion efficiency that maters. This Energy-Density (http://en.wikipedia.org/wiki/Energy_density#Energy_density_in_energy_storage_an d_in_fuel) chart gives some usefull numbers for comparison.

My guess is that we will soon see supercapasitors and motorized wheel-hub assemblies as light weight hybrid retrofits for older cars.

For base energy storage, pumping water to a higher elevation seams to be much more efficient than I had thought. The energy density is lousy but doesn't matter.

[Schneibster]

Well, at a certain point real estate starts to matter. I have to say, though, that storage of gravitic potential energy in the form of water has its attractions.

[steve s]

For base energy storage, pumping water to a higher elevation seams to be much more efficient than I had thought. The energy density is lousy but doesn't matter.


I have to say, though, that storage of gravitic potential energy in the form of water has its attractions.


Until your hilltop reservoir collapses. (http://www.semissourian.com/story/1131499.html):eek:

http://www.semissourian.com/photos/10/47/66/1047663-L.jpg

Steve S.

[robinson]

Nobody expects the hilltop reservoir collapse!

[Schneibster]

Until your hilltop reservoir collapses. (http://www.semissourian.com/story/1131499.html):eek:

http://www.semissourian.com/photos/10/47/66/1047663-L.jpg

Steve S.Any way you store energy, there's a potential for something bad to happen if it's released without control. Choose your poison. At least water spilling doesn't create a chemical hazard.

[robinson]

Reading up on the solar power plants being built, they store heat and produce power 24/7

I was curious about the cost, that usually being the bottom line in these matters. From what scant information available online, it seems that solar power is the next gold rush. Large scale plants, connected to current grids, have the potential to make money, and not 20 to 30 years later, but right now.

Cynical opinion has been that if you could patent sunshine, solar power would be everywhere, just like oil and gas. It isn't for sure yet, but it looks like it is possible to sell sunshine using these large scale solar power collectors. And make a profit.

Not only is it cleaner than oil, coal or nuclear, there are two huge factors that make this a profitable enterprise. No fuel cost, and very small labor cost.

[Michael Redman]

Someone else is thinking of investing in solar: http://www.msnbc.msn.com/id/21253268/

[Dan O.]

That flimsy space junk will be an easy target for a ground based solar array.

[robinson]

I was thinking that space junk would make a really really bad ass weapon. Beam that solar energy down on the enemy, game over man, game over.

[robinson]

Of course that is probably what they are really doing. Building a huge space based solar powered death ray.






















Hey, somebody has to do it. How can you have an evil empire without a giant death ray?

[Dan O.]

Look closer. This is nothing more than a hugh array of mirrors to catch military spending and redirect it into private hands. The illuminated hands have probably already been chosen.

[luddite]

Just peeked into this thread. Energy storage is actually a lot more advanced than most people know about. It isn't used because meeting peak load is a lot cheaper with coal. I actually calculated the cost compared to using natural gas for peaking and it turned out favourable, at least for some kinds of storage.

As far as I know, the cheapest storage is hydroelectric reservoirs that aren't running at full capacity. That's the case for most of Quebec and Manitoba. Beyond that, pumped hydro comes out cheapest, but it requires good geographic conditions. But coming up close behind are two others. The first is compressed gas storage, but that requires specific geological conditions. The other, available anywhere and scalable from zero to hundreds of megawatts (though the target market for the manufacturer is upwards of 10 kW, I believe, and they've never done anything larger than 30 MW) is the flow battery.

http://www.vrbpower.com/technology/index.html

The exciting thing to me about the vanadium redox flow battery is that both sides of the battery contain the same material: vanadium in dilute sulfuric acid. Consequently, they do not suffer from "poisoning" across the membrane which eventually renders all other batteries useless and leaves a toxic and useless mess to deal with. The electrolyte in a flow battery is essentially useful forever.

In jurisdictions that value wind and want to balance or "firm" it up, VRB Power Systems can be quite competitive. They have installed batteries on wind farms in Japan, England and Ireland. The product is also used for grid support or to reduce the necessity of expensive transmission upgrades in the United States and South Africa. It is being aggressively marketed for remote area support to increase the use of wind over diesel alternatives, with sales in Australia.

There are also other emerging storage technologies. There's a small community in Alberta that stores heat in underground reservoirs. There are flywheels and capacitors.

But I suspect that the biggest storage gains will be made through human manipulation of the time of energy use. In a well-insulated home, for example, it's not necessary to heat or cool at any particular time of the day. My washing machine now has a 3-hour delay button. I can only imagine that machines of the future will be set to optimize the washing time from utility signals.

[TjW]

<snippage by TjW>
But I suspect that the biggest storage gains will be made through human manipulation of the time of energy use. In a well-insulated home, for example, it's not necessary to heat or cool at any particular time of the day. My washing machine now has a 3-hour delay button. I can only imagine that machines of the future will be set to optimize the washing time from utility signals.

Oh, that advanced technology stuff. My mom lived for awhile in Santa Fe, in a house about two hundred years old. It had adobe walls about thirty inches thick. It seemed to have a heat delay of about ten hours. In the summer, it would stay cool inside all day, then start to gently warm up around dusk.