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Ariz. Team Seeks Fossil-Fuel Cost Parity, Using Solar Energy Concentrators
autospa writes "A University of Arizona engineering team led by Roger Angel has designed a new type of solar concentrator that uses half the area of solar (PV) cells used by other optical devices and delivers a light output/concentration that is over 1000 times more concentrated before it even hits the cells. This comes as a result of a broader goal to make solar energy cost competitive with fossil fuels (target = 1$/W) without the 'need for government subsidization.'"
It's hard to count all the ways our oil economy is supported and subsidized by the government. And we haven't even started cleaning up the mess yet.
without the “need for government subsidization.”
ALL sources of energy receive subsidy. some examples : Oil (how much did all those wars cost?), coal(damage to public health=hidden subsidy), nuclear(research since the forties)
Yes, I'm left. You have a problem with that?
I pay about $0.10/kWh. (1000 W per Hour)
“Common sense is not so common.” — Voltaire
I always suspected that PV technology was just missing a glowing crystal ball.
To the stars, Merlin!
If you are using concentrators for solar power you really ought to consider a thermal cycle like a brayton turbine or a sterling engine, rather than solar cells. Thermal cycles tend to have higher conversion efficiencies, the equipment is more reliable, and their power output is more easily converted to grid voltage ( AC as opposed to DC ). Solar cells also tend to see reduced lifetimes when used with very concentrated light. The advantage with cells is pretty much that they don't need concentrators to work, since they don't rely on a high temperature. They can also be used in places where space/weight is an issue, such as on sailboats, rooftops or sattelites. Thus if you are already using a bulky concentrator to get the light intensity up, you may as well use a sterling engine.
If only somebody would invent some sort of device that could store electricity for later use.
Then I could finally ditch the diesel generator I have to drag around to keep my mp3 player running!
Yeah, those subsidies clearly don't exist. That's why at one point Obama claimed he was going to cut $36.5 billion in them.
... ATTACK!
... And when we get the energy ...
... GET DRUNK!
Who ever claims that solar is for everyone despite a minority of kooks? Anyone sensible knows that you need to store excess generated energy in batteries for later or to have a backup generator for when night comes. What you are doing is the classic strawman.
And then you'd have the fun and moral satisfaction of purchasing a new set of heavy duty batteries every year or two. Mind you that would be a very large set, to account for the possibility of many short cloudy winter days in a row.
That's somewhat of a misnomer. The subsidies are mostly tricks to get the oil industry to invest in areas that are not profitable for them and they wouldn't otherwise be at.
In more plain terms, if the subsidies didn't exist, oil companies would not miss them, they simply would not be doing some of the things they are now at the request of the government. Eliminating those subsidies would have no real noticeable effect on price or profit.
And yet despite claims that they wouldn't miss them, they continue to lobby and fight against their removal.
Look into the efficiency of a battery sometime. Unless you buy really expensive ones you lose about half of the energy putting it into and getting it back out. More losses if you are putting in AC and needing AC back out. And the really good (from an efficiency pov) lithium-ion batteries don't suffer many charge discharge cycles before hitting the 50% capacity point generally considered as replacement time. We currently have zero methods to store electricity that are cheap enough and effective enough for use on the grid. All electricity is generated as needed, with vast arrays of 'peaking power' generation capacity that largely sits idle. Believe me, if there were a good way to store electricity the industry would be using it already.
Worse, while electricity can be sent large distances, it is best to generate close to the point of use because of the line losses. So even if we were willing (and shot enough enviromentalists) to cover our deserts with solar arrays we would lose most of the power heating the lines getting it to where the customers are. Same for wind, it mostly occurs in areas where there aren't many people... or more accurately windmills near populated areas attracts more environmentalists.
Democrat delenda est
If electricity is cheap in the daytime and scarce/expensive at night, the market will figure it out.
Maybe that means people have incentive to charge their cars at work. Maybe it means entrepreneurs buy excess electricity on the spot market during the daytime, use it to pump water uphill, and use the potential energy of that water to generate more expensive electricity at night. (Is that process lossy? Sure! But the market will only reward it if it provides a net benefit, so it's all good. Same for battery / ultracapacitor / other technologies -- if they're a good fit for the problem, someone will make money using them; if not, they won't).
Which sort of makes my point for me. If the power source needs a diesel backup that's going to be used often enough (ie some/most of the winter?), then it's not it's not as viable a source of renewable energy as that same diesel running on synthetic fuel would be. Unfortunately, there is not (yet) a viable large scale production capacity for synthetic fuel. Equally unfortunate is that people and research funding bodies have this solar pathology tattooed on their brains.
1) Solar panels produce direct current, not alternating current. Direct current is almost impossible to transmit across any meaningful length of electric cable.
2) Converting DC to AC is possible, however there are efficiency losses and thermal losses - these come out of your "profit"
3) At some point you are going to need to replace your solar panels - they only last 15-25 years. You need to set money aside for this, unless you plan on shutting down your plant at the end of 15 years.
4) Energy companies do not buy electricity at the same price at which they sell it to you. Often there is a HUGE discrepancy. Ahh, monopolies.
5) The obvious one - the sun doesn't shine 8 hours a day so your 1MW system will probably deliver 300kW every hour on average.
6) To provide power at night you will need some means of storing energy. Batteries work, but they need maintenance and they do wear out over time. Less profit.
Oh - suddenly it's not so profitable anymore.
Seven puppies were harmed during the making of this post.
Direct current is almost impossible to transmit across any meaningful length of electric cable.
Humorously, you have it exactly wrong. The longer the cable, the (relatively) cheaper the cost of HVDC conversion gear vs the rest of the project.
The power delivered by a AC line is based on the RMS voltage. However you have to insulate to peak, which is somewhat more. Insulation is a pretty major design constraint, as arcs to the ground or towers is kind of a waste of power...
As a very rough guess on a medium length line you can push about 1/4 to 1/3 more power for the same cost if you switch to DC.
The power levels I'm talking about are a couple GWs, distances of dozens of miles, costs vaguely around gigadollars. Capital costs of about a buck a watt per 50 miles, lets say. You can see the motivation of placing plants nearby cities, rather than in the middle of nowhere.
You can do long distance AC, and they used to, it just costs a heck of a lot more.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
I just assumed you were posting from the UK.
They do? Your right, because they can explore other areas of business and develop techniques to deal with it in the future without a large loss. However, that doesn't mean they would continue to do so if they were removed.
I didn't say there wasn't a benefit for them. I said the benefit wouldn't effect their profit or prices if it was removed. Instead, they would just go back to what's normally profitable until such time prices are high enough for them to get into those areas on their own.
Hmm? I thought the whole reason we use AC (thanks to Edison winning the argument with Tesla) was because there is less loss over long distances when compared to DC. Edison wanted One Big Plant generating power, and Tesla wanted many small, local plants. I guess I will have to re-read this - I apologize, I'm a biologist not a physicist.
Seven puppies were harmed during the making of this post.
We have an energy surplus at night, due to things like nuclear facilities that run at the same output no matter the demand. Really, we need to expand our power system to handle larger peak energy during the day, when everyone is running their air conditioners. Expanding into more nuclear is politically difficult. Gas and Coal are polluting. Solar would help us during the day, when power usage is highest.
So no, no one energy source can be our only generation point. But solar could definitely help when it is needed most.
The ______ Agenda
"We in the West are pretty clean for the most part - it's getting India, China and other developing countries to clean up..."
What the hell are you smoking? Or more aptly, what planet are you living on?
A person living in China is responsible for 17% as much greenhouse-gas emissions as is a person living in the United States.
A person living in India is responsible for 8% as much greenhouse-gas emissions as a person living in the United States.
http://en.wikipedia.org/wiki/List_of_countries_by_greenhouse_gas_emissions_per_capita
and that's not even accounting for the fact that much of the most polluting parts of the Chinese and Indian economies are devoted to supplying the West with goods.
Where are we going and why are we in a handbasket?
Back in the original AC vs DC battle it was damn near impossible to raise DC voltages and damn difficult to lower them without wasting a large part.
With AC a simple power transformer could raise the voltage on the lines. In the old days AC had a massive transmission line voltage advantage. These days it has the RMS disadvantage.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
Hmm? I thought the whole reason we use AC (thanks to Edison winning the argument with Tesla) was because there is less loss over long distances when compared to DC. Edison wanted One Big Plant generating power, and Tesla wanted many small, local plants. I guess I will have to re-read this - I apologize, I'm a biologist not a physicist.
You mean the argument that Edison *lost* - he was the big proponent of DC, while Tesla and Westinghouse were behind AC.
Don't tell me to get a life. I had one once. It sucked.
Wow, umm no.\\
Go back and check your history. Edison LOST that argument with Tesla. Tesla wanted AC because it was better for running motors and was more efficient for long distance transmission. Edision wanted DC because its arguably safer.
Repeal the 17th Amendment TODAY! Also Please Read http://www.gnu.org/philosophy/right-to-read.html
What the hell are you smoking? Or more aptly, what planet are you living on?
I think it's more a question of what he's NOT smoking. Only hippies and potheads would look at GHG output as a measurement of how "clean" a country is. Not to mention the foolishness of comparing per-capita emissions between two nations of such wildly different industrial capability. It's like claiming that the homeless guy who keeps shitting in the middle of the street is more "clean" than me because he doesn't have a car.
Sorry, but of course their numbers look good. Take away all their outer areas and the populations who basically are barely powered by anything and you get more reasonable. Look at their air quality in their major cities. Check their rivers and the like.
Per capita and they are broke too, but I don't think its a fair number to evaluate the earning power of those with modern jobs.
* Winners compare their achievements to their goals, losers compare theirs to that of others.
With the technology of the time, sure. Modern semiconductors have made high voltage DC-DC conversion pretty darn efficient though:
"For long-distance transmission, HVDC systems may be less expensive and suffer lower electrical losses" -- http://en.wikipedia.org/wiki/Hvdc
Also, brushless DC motors have also made AC pointless (to an extent).
DRM 'manages access' in the same way that a prison 'manages freedom'
Come to think of it, why not use a bimetallic strip to move the panels? Have it set up to face east when the strip is cold, and as it heats up and starts to bend, use it to push the face of the panels to follow the sun.
They sentenced me to twenty years of boredom
Edision wanted DC because its arguably safer.
Edison wanted DC because it was what he had started working with, and he wanted to keep using it.
The ironic thing though is that high voltage DC is actually kind of dangerous to work with, more so than similar AC voltages. This is because of the way inductance and capacitances behave as the frequency increases. As the frequency increases a capacitance starts to look more like a short, while an inductance starts to look more like an open. At DC (IE, at 0 Hz), it is the opposite. In DC, an inductance will resist changes in current. This makes it harder to build DC overcurrent protection devices, as in the event of a short the inductance inherent in the wiring can cause a voltage spike which can maintain an arc. In alternating current the zero crossing (every 8.3 ms at 60 Hz) inhibits this. Lack of a zero crossing can also make it harder to "let go" if you come in contact with a live wire.
At transmission-type voltages, though, like what you'd use to get power across the country it's kind of a moot point as you don't really want to get between either of them and ground.
Saying "I'll probably get modded down for this" in a post is the best way to get it modded up.
It's difficult to argue though, that the tax payer should subsidize exploratory ventures for companies which make some of the largest profits on the planet. In short, they could afford these ventures on their own with no help from the taxpayer. It is to their benefit to keep the taxpayer addicted to oil as long as possible. About the only karmic result of all this is that the oil industry will eventually have to expand into other energy sources or face extinction.
As a taxpayer, I say the sooner the better. Total dependency on an energy source that we do not and cannot control is borderline insanity.
That said, I happen to agree that some government incentives for alternate fuels is absolutely necessary. Sometimes they do 'hit the jackpot' so to speak, and if such ventures into solar prove to be a feasible alternative fuel, then I would consider that money well spent.
There's really two parts to answer this.
First, it's not really all that difficult when you understand the pork barrel spending. 70% or more of the subsidies is designed to keep the oil companies in an area in which a congress person would benefit from. Some of it happens to do with keeping jobs, others is keeping revenue from well leases and so on. I completely understand what you are saying though, but if you approach it already knowing that the oil companies don't need it, you can start to see who does.
The second part, It is not only a karmic results, it's what some of the subsidies are designed to do. The oil industry already has the distribution network there, the processing capabilities and expertise, it's just a matter of jobs being kept to get them to transition close to how it is now, verses off shoring everything. There is a large push (concealed within some of the subsidies) to get oil companies into alternative energy sources sooner then later. Perhaps much sooner then karma alone could accomplish.
Yes, I agree. The problem is, currently, we don't have a comparable replacement. What this and other stories seem to glance past, (maybe it's just the commentators), is that when we inflate energy costs and alternatives not otherwise become viable, it crashes our economy. Sure, there was a lost more to it, but we can't discount the impact that high prices for energy played into it. It sucked the free money away from everyone.
I agree too. Except I think we need more of an investment into the raw sciences to make it happen then into an industry. Either way, something happening overnight will not come out well. It will take 20 or more years to replace the majority of oil dependent embedded infrastructure as soon as something is figured out.Cars, machinery, HVAC systems, all need to see the end of a useful life instead of expecting people to just throw them out for the next big thing.
It's like claiming that the homeless guy who keeps shitting in the middle of the street is more "clean" than me because he doesn't have a car.
By just about any metric besides "which one looks grosser" that homeless guy is almost certainly cleaner than you. You drive a car that introduces pollutants of various kinds into the environment, and which involves all sorts of dirty processes to extract fuel for, not to mention the initial construction. Your home is mostly likely powered in part by coal, which introduces plenty of nasty stuff including radioactive ash into our atmosphere. Each year, you probably produce a mountain of trash that would dwarf that homeless guy's little steaming pile, and when you take a dump, your convenient indoor plumbing dirties up a gallon+ of water that is more drinkable than that in much of the world.
Just because you don't see it festering in the middle of the street doesn't mean you aren't shitting all over the place yourself.