But what is the conversion efficiency of the new solar panels they're describing? I.e., if 100 watts of light hits it, how many watts of electricity comes out?
I guess, though, if you can manufacture it cheaply enough to spam it over every man-made surface in a city, you could overcome some inefficiency... But the article still left me confused as to whether the described technology is more efficient, less, or the same, as what we have now.
The absolute efficiency isn't very important. To quote Earth: The Sequel again, "At just 10% efficiency-- that is, if only 10 percent of that solar energy were converted to electricity-- no more than a square of land 100 miles on a side would be needed to produce enough electricity to power the entire United States." (The thin-film CIGS type tech described in this article is typically a little less than 10% efficient, so pretty good.)
The key statistic is being able to calculate when solar is cost competitive with coal, because once you hit that point it will start showing up everywhere. Of course this depends on where you live, because different regions of the country A) receive differing amounts of sunlight B) pay differing rates for the amount of electricity generated. If you're talking about an area like LA where there is a lot of sunlight and electricity costs a lot, solar is already probably cheaper than coal. In Fairbanks, AK on the other hand it will take a bit longer.
Another key to getting solar to be cheaper than coal is implementing real-time pricing. To quote again,
"Though solar power is generally judged on the basis of whether it can beat the retail price of coal-generated electricity, the comparison is in some ways misleading. The true value of solar power lies in the fact that it is most productive when the weather is sunny and hot-- precisely when consumer demand forces a utility to operate at full throttle. According to PG&E, peak demand is growing 25 percent faster than overall electricity needs, but the last quarter of capacity is needed less than ten percent of the time. 'Peak shaving' with electricity produced by rooftop solar panels relieves that pressure on utilities, damping the prime driver to build new gas-fired plants. It also reduces costs. Utilities "turn on" power plants in order of their variable cost, often called "dispatch cost," starting with the least expensive plant to operate and moving to the most expensive as demand rises. Solar installations produce electricity at virtually no extra cost at just the same time when units with very high variable costs are called upon to run. By displacing these high-variable-cost units, solar units can provide tremendous savings for the utility and the consumer-- and the atmosphere."
"To date, however, most owners of solar photovoltaic systems owners do not get the discount they deserve on their electric bills. Typically, utilities charge customers using a weighted average of the cost of generating electricity over the course of a day. Some jurisdictions are now experimenting with a different rate structure-- 'real time pricing'-- charging customers hour by hour for the true cost of the electricity they use, and thus allowing them to reap the full value of avoiding the cost of peak power on the grid."
"Given all that, almost everyone in the industry agrees that when the price per peak watt falls to $1 and the storage problem is solved, solar-generated electricity will compete with coal-fired electricity virtually everywhere." (p. 19)
Efficiency is important - it's what lets you put the panels some place other than a giant solar farm in the middle of no where.
Consider house-top installations. If each only produces 100 watts, the cost of the inverter and utility hookup will make it untenable even if the panels are free. (Inverter cost/watt goes down pretty fast with capacity and most of the hookup cost is independent of the capacity.)
There's also a huge psychological boost in being able to be energy neutral.
Of course efficiency is important. 10% is horrible by today's standards. They are up to 20%, which would save you half of the panels cutting your costs in half. The cost (or revenue) of an installation is directly connected to the efficiency of your solar-technology. If you only have a fixed space to build it in, and your panels are twice as efficient, you make twice as much power and twice as much energy.
Price isn't proportional to efficiency. Making a solar panel that's 10% efficient instead of 20% efficient might require only 1/20th as much silicon. Also, the current limiting factor is the cost of manufacturing, not the cost of land. That's why companies are racing to build a new generation of low-efficiency low-cost photovoltaics.
When did doubling the size of my roof become cheaper than a solar system?
Silicon isn't the only cost. As I wrote, inefficient technology makes small systems uneconomic.
FWIW, the systems with the highest efficiency right now actually have less silicon than typical rooftop systems.
Note also that there is no one "cost of silicon" - silicon prices vary widely. Many of the low-silicon cost/efficiency systems actually use more silicon than some of the high-cost/high-efficiency systems.
If its really inneficient, its like, whats the point? Its easier from a manufacturing standpoint to make something cheaper than more efficient. The efficiency often lies with the underlying physics and often hits a hard theoretical limit that can't be passed because it violates thermodynamics, or something like that. If you came up with an amazing system that was horribly expensive to produce but waaay more efficient than everybody else, you'd still get rich because some large technology company would buy it and figure out how to use scale and other techniques to bring the price down. Just like plasma TVs. They cost an order of magnitude less than they did 7 years ago, but their picture quality hasn't changed by an order of magnitude. (its hard to measure picture quality in quantitative terms, but you get the point).
I'm all for alternative energy, but if the only chance of it becoming cost competitive with coal is to artificially jack up the price of the current system through caps, I doubt Congress will pass it through. Even if they do, once it shows up in the consumers bills, there will be hell to pay.
The best approach is to increase the efficiency through science and let the technology naturally be adopted like every other innovation that wins in the marketplace. I'm still for the cap, but if that is the linchpin for adoption to take hold widespread, something must be wrong with the product.
The point of a cap is that it places a legally binding limit on the total amount of CO2 that can be released into the atmosphere. Alternative energy achieving price parity with coal is just the natural result of internalizing the negative externality of our currently broken system.
My point was more along the reactive lines to a price increase of energy. Regardless of the positive environmental result, which I applaud, if middle America sees it's utility bill increase by a significant percentage, whoever has their name attached to the legislation that caused it is at serious risk of being voted out.
Note also that an increase in the price of energy causes prices across the board for every manufactured item to increase. Classic inflation, 1970s style. This is not the best economic environment to cause inflation in.
The specific technology mentioned in this article requires Indium. To quote Earth: The Sequel, "In July 2006 International estimated that the global indium supply was enough for just 4 gigawatts of CIGS. Scarcity has already affected the semiconductor's price, which in 2007 was triple what it had been in 2002."
To put the 4 gigawatts figure in perspective, "Industry research firm Clean Edge predicts that revenues in the solar photovoltaic industry will grow to $50 billion a year by 2015, reaching a total installed base of 75 gigawatts, a tenfold increase from today. But that would supply just .5 percent of the total amount of electricity needed for 2015. A more rapid expansion will almost certainly require the second-generation photovoltaic technologies now emerging from labs into the commercial market."
Wikipedia suggests the problem may be solvable in the long run, but economics are pretty uncertain for the time being:
One idea that I've heard mentioned a few times is to use a percentage of the stored energy in electric cars to help power the grid overnight. The car owners would have to be compensated, but as battery technology improves (it has its own Moore's Law equivilant but the period of doubling is much longer), say, 20% of the energy stored in cars would end up being a very significant amount.
There is a problem with the idea though. Part of the reason why electric cars are attractive is that you can charge them overnight in such a way that it levels out the power demand, which makes power generation cost less. Not to mention many commute patterns mean that cars are not at home during the peak hours of electricity generation.
The existing plants prove that concentrated solar power is practical, but costs must decrease. Electricity from solar thermal plants currently costs between US$0.13 per kilowatt hour (kWh) and US$0.17 per kWh, depending on the location of the plant and the amount of sunshine it receives. Conventional power plants generate electricity for between US$0.05 and US$0.15 per kilowatt hour (not including any carbon taxes or cap and trade related costs) but in most places it's below US$0.10 (wind power generally costs around US$0.08 per kWh).
I wonder how long it's going to take solar-thermal to gain traction. The economics seem a lot better than just plain photo-voltaic solar that's been pushed for years. And certain types of solar-thermal have an energy reservoir, so you can have peak load + base load capabilities, unlike wind power.
The "tipping point" will arrive when the capital cost of solar power falls below $1 (51p) per watt, roughly the cost of carbon power. We are not there yet. The best options today vary from $3 to $4 per watt - down from $100 in the late 1970s.
Who wants to bet, that when solar power becomes as cheap or cheaper than fossil, oil prices will magically plummet with some half-assed explanation as to why. Sort of like the reasons prices are increasing now, just in reverse (except no one will care)
Yes, oil prices will decline, but there's a real, sensible reason! (not "some half-assed explanation" like you say)
It's basic economics. Cheap solar power (a substitute for oil) will reduce demand for oil ... so the market price of oil will decline if the supply of oil is the same. But oil isn't traded on a free market, so it's a bit more complicated.
Concentrated Solar Thermal is more than 90% efficient. Ausra has a 175Mw base-load plant in construction. A number of Gigawatt plants will be made within a few years.
In China, there are 30 million solar hot water systems capturing the energy of 40 large nuclear plants and is growing at 20% per year. South Africa has mandated all buildings have to have solar hot water by 2010.
My company will install thousands of solar hot water systems without change and we will get the carbon credit and charge for the 'free' energy captured from the sun.
The first thing the author's name makes me think of:
"A sonnet by Byron might score high on the vertical but only average on the horizontal. A Shakespearean sonnet, on the other hand, would score high both horizontally and vertically, yielding a massive total area, thereby revealing the poem to be truly great. As you proceed through the poetry in this book, practice this rating method. As your ability to evaluate poems in this matter grows, so will, so will your enjoyment and understanding of poetry."
24 comments
[ 73.5 ms ] story [ 1470 ms ] threadI guess, though, if you can manufacture it cheaply enough to spam it over every man-made surface in a city, you could overcome some inefficiency... But the article still left me confused as to whether the described technology is more efficient, less, or the same, as what we have now.
The key statistic is being able to calculate when solar is cost competitive with coal, because once you hit that point it will start showing up everywhere. Of course this depends on where you live, because different regions of the country A) receive differing amounts of sunlight B) pay differing rates for the amount of electricity generated. If you're talking about an area like LA where there is a lot of sunlight and electricity costs a lot, solar is already probably cheaper than coal. In Fairbanks, AK on the other hand it will take a bit longer.
Another key to getting solar to be cheaper than coal is implementing real-time pricing. To quote again,
"Though solar power is generally judged on the basis of whether it can beat the retail price of coal-generated electricity, the comparison is in some ways misleading. The true value of solar power lies in the fact that it is most productive when the weather is sunny and hot-- precisely when consumer demand forces a utility to operate at full throttle. According to PG&E, peak demand is growing 25 percent faster than overall electricity needs, but the last quarter of capacity is needed less than ten percent of the time. 'Peak shaving' with electricity produced by rooftop solar panels relieves that pressure on utilities, damping the prime driver to build new gas-fired plants. It also reduces costs. Utilities "turn on" power plants in order of their variable cost, often called "dispatch cost," starting with the least expensive plant to operate and moving to the most expensive as demand rises. Solar installations produce electricity at virtually no extra cost at just the same time when units with very high variable costs are called upon to run. By displacing these high-variable-cost units, solar units can provide tremendous savings for the utility and the consumer-- and the atmosphere."
"To date, however, most owners of solar photovoltaic systems owners do not get the discount they deserve on their electric bills. Typically, utilities charge customers using a weighted average of the cost of generating electricity over the course of a day. Some jurisdictions are now experimenting with a different rate structure-- 'real time pricing'-- charging customers hour by hour for the true cost of the electricity they use, and thus allowing them to reap the full value of avoiding the cost of peak power on the grid."
"Given all that, almost everyone in the industry agrees that when the price per peak watt falls to $1 and the storage problem is solved, solar-generated electricity will compete with coal-fired electricity virtually everywhere." (p. 19)
Consider house-top installations. If each only produces 100 watts, the cost of the inverter and utility hookup will make it untenable even if the panels are free. (Inverter cost/watt goes down pretty fast with capacity and most of the hookup cost is independent of the capacity.)
There's also a huge psychological boost in being able to be energy neutral.
Silicon isn't the only cost. As I wrote, inefficient technology makes small systems uneconomic.
FWIW, the systems with the highest efficiency right now actually have less silicon than typical rooftop systems.
Note also that there is no one "cost of silicon" - silicon prices vary widely. Many of the low-silicon cost/efficiency systems actually use more silicon than some of the high-cost/high-efficiency systems.
The best approach is to increase the efficiency through science and let the technology naturally be adopted like every other innovation that wins in the marketplace. I'm still for the cap, but if that is the linchpin for adoption to take hold widespread, something must be wrong with the product.
Note also that an increase in the price of energy causes prices across the board for every manufactured item to increase. Classic inflation, 1970s style. This is not the best economic environment to cause inflation in.
To put the 4 gigawatts figure in perspective, "Industry research firm Clean Edge predicts that revenues in the solar photovoltaic industry will grow to $50 billion a year by 2015, reaching a total installed base of 75 gigawatts, a tenfold increase from today. But that would supply just .5 percent of the total amount of electricity needed for 2015. A more rapid expansion will almost certainly require the second-generation photovoltaic technologies now emerging from labs into the commercial market."
Wikipedia suggests the problem may be solvable in the long run, but economics are pretty uncertain for the time being:
http://en.wikipedia.org/wiki/Indium
There is a problem with the idea though. Part of the reason why electric cars are attractive is that you can charge them overnight in such a way that it levels out the power demand, which makes power generation cost less. Not to mention many commute patterns mean that cars are not at home during the peak hours of electricity generation.
The existing plants prove that concentrated solar power is practical, but costs must decrease. Electricity from solar thermal plants currently costs between US$0.13 per kilowatt hour (kWh) and US$0.17 per kWh, depending on the location of the plant and the amount of sunshine it receives. Conventional power plants generate electricity for between US$0.05 and US$0.15 per kilowatt hour (not including any carbon taxes or cap and trade related costs) but in most places it's below US$0.10 (wind power generally costs around US$0.08 per kWh).
I wonder how long it's going to take solar-thermal to gain traction. The economics seem a lot better than just plain photo-voltaic solar that's been pushed for years. And certain types of solar-thermal have an energy reservoir, so you can have peak load + base load capabilities, unlike wind power.
Nanosolar is "the first solar manufacturer capable of profitably selling solar panels at as little as $.99/Watt" (http://www.nanosolar.com/blog3/2007/12/18/nanosolar-ships-fi...)
edit: after the post, I remembered that the cost of a solar panel is only about half the total cost of solar power.
They've also claimed that they were going to build a factory capable of producing 430 MW of panels annually by the end of 2007, which hasn't happened.
I'll be their biggest fan if they succeed, but so far, they're making big claims, soaking up VC funds, and shipping little product.
It's basic economics. Cheap solar power (a substitute for oil) will reduce demand for oil ... so the market price of oil will decline if the supply of oil is the same. But oil isn't traded on a free market, so it's a bit more complicated.
In China, there are 30 million solar hot water systems capturing the energy of 40 large nuclear plants and is growing at 20% per year. South Africa has mandated all buildings have to have solar hot water by 2010.
My company will install thousands of solar hot water systems without change and we will get the carbon credit and charge for the 'free' energy captured from the sun.
"A sonnet by Byron might score high on the vertical but only average on the horizontal. A Shakespearean sonnet, on the other hand, would score high both horizontally and vertically, yielding a massive total area, thereby revealing the poem to be truly great. As you proceed through the poetry in this book, practice this rating method. As your ability to evaluate poems in this matter grows, so will, so will your enjoyment and understanding of poetry."
I don't hear enough rip!