10 ms·

Solar PV rapidly becoming the cheapest option to generate electricity

125 points by ph0rque 15y ago

00joe 15y ago
sunelec.com, PV Panels $1.28 Peak watt, Inverter $0.5 watt, Rails and Cables $0.27 watt. In my area I expect to save .18 cents per year per peak watt. Prices have been falling at 1-2 cents a week since june. http://pvinsights.com/ http://pvinsights.com/
droithomme 15y ago
This is true for deep space satellites and locations where running a power line is cost prohibitive, such as weather monitoring stations in Antarctica.
- CapitalistCartr 15y ago
  It's also true in parts of Florida. In rural areas, PV can be cheaper than paying the power company to run out their lines. I expect, in five years, it'll be worth my while to put them on my house, in the middle of the city.
pingswept 15y ago
I've found Travis Bradford's book Solar Revolution to give a good overview of the solar industry, with the same numerate feel as this article: http://www.prometheus.org/research/solarrev http://www.prometheus.org/research/solarrev The best rebuttal I've heard (to renewables generally, not PV specifically) is the second to last chapter of Matt Ridley's The Rational Optimist: http://www.rationaloptimist.com/books/rational-optimist-how-prosperity-evolves http://www.rationaloptimist.com/books/rational-optimist-how-... (Sorry I can't link directly to the content, but so far as I know, it's not available online in either case.)
- Lost_BiomedE 15y ago
  Thanks. I will have to get 'The Rational Optimist'. Matt Ridley's book 'Nature via Nurture' impacted me a lot when it first came out. The online course 'Physics for Future Presidents' taught me a lot about how to evaluate energy sources. I would recommend it to anyone interested in learning the physics concepts behind many hotly debated areas, whom currently has little knowledge or exposure in this area.
- schiffern 15y ago
  As far as Matt Ridley's writing, can you speak to whether these are the same arguments: http://online.wsj.com/article/SB10001424052748703421204576327410322365714.html http://online.wsj.com/article/SB1000142405274870342120457632... ? Summarized, Ridley argues here that the "renewable/non-renewable" distinction is quantitative (not qualitative), and that renewable energy harvesting devices are built from non-renewable materials.
  - pingswept 15y ago
    Some of the arguments in that article are repeated in the book, but it's not the main thrust of the chapter I was referring to. I'm afraid I gave the book to my brother after I read it, so I can't give you an authoritative summary of the arguments in the book. As best as I can recall, the argument was renewables generally have such low power density (W/m^2) and high energy cost ($/J) that they are unlikely to be an effective solution to climate change, should climate change be as severe as we fear it might be. (Ridley is not a climate change denier, but he does think scientists' worst fears are exaggerated. Here's an audio interview with Ridley that might cover some of the same stuff in the book: http://www.econtalk.org/archives/2010/10/ridley_on_trade.html http://www.econtalk.org/archives/2010/10/ridley_on_trade.htm...
marze 15y ago
It is surprising how little attention has been created by this huge PV panel price decrease, from $4.00 a watt to $1.25 in three years. Solyndra is an early casualty, since their business model depended on PV panel prices to fall much more slowly. The economics of home based solar electricity depends on three numbers, the panel price, the local retail electric rate, and the interest rate of the loan for the system. Right now, in much of the US, you can see that a PV system makes sense for new construction. A simple example: $12500 : 4500 W PV system w/no storage (grid backed up) 4% interest rate, payment of $60/month $0.11 per kwh avoided cost, the system generates about $70 of electricity/month In a nutshell, this is grid parity, right now in 2011. And the owner of such a system does not need to worry about utilities increasing their rates over the years.
- brc 15y ago
  Does your example include a FIT (feed in tariff) provided by government at a much higher rate than grid power, or are you doing a calculations at grid power? A lot of places have a high FIT value currently, but this is subject to political whims and any incoming government might find it easy to gain votes by trimming the FIT, as has already happened in many places around the world. Another huge problem with these calculations is the very small fraction of people who stay in one house for more than 10 years. Essentially you have to stay in the house for the entire payback period or you've lost out. Personally I think the solar price will have to drop to the point where it is much lower than grid (with no subsidies), rather than just about equal. At that point, takeup will be much higher.
  - compman775 15y ago
    Why would you have lost out? Couldn't you sell the house for more than you could have if you hadn't had solar panels installed?
  - marze 15y ago
    No, just avoided cost. Unless your utility drops the rates significantly, the savings are locked in. As far as moving goes, studies show that solar systems increase the value of a house by approximately the cost of the system. Of course, if solar system prices fall as expected, this premium would likely drop also. And the economics are the same for a system where the cost is rolled into a loan during a home loan refinance, an option available to many people now.
ars 15y ago
Too many assumptions. The biggest of course is that that "22%" number will continue despite the fact that "the learning rate has been exceptionally high". Another assumption is that natural gas prices will stay the same, when actually they are going down right now. Not an assumption but rather an omission: He uses a 25 year payback period for solar, but does not include opportunity cost of that money (i.e. how much that money would have brought in interest) over 25 years. Once you include that (and you should) it doesn't look as good. And in any case 25 years is far too long. 10 years is the standard for evaluating payback periods. 6% over 25 years is 4.5 time the base value. So the solar power actually costs 4.5 times as much as he assumes. Even assuming just 3% would give you 2.1 times your cost. Edit: These calculations are a bit off since they assume paying for the standard power all at once at the end, but actually you make payments throughout.
- biot 15y ago
  He says that $700 worth of solar cells would produce 4000kWh of electricity per year which is what the average family consumes. Over the course of 25 years ("a lifetime of household electricity") had you purchased that from the grid, it would have cost $25,000. Ignoring maintenance, you get $25,000 worth of electricity for an initial one-time investment of $700. Though that's production cost, and excludes installation, maintenance, etc. so likely multiples of that at retail. I think you misread the 25 years as being a payback period.
  - anamax 15y ago
    > Ignoring maintenance, you get $25,000 worth of electricity for an initial one-time investment of $700. Though that's production cost, and excludes installation, maintenance, etc. so likely multiples of that at retail. Something is wrong here. Installation is maybe $3k. The typical retail markup is 2x. So, let's call it $5k. 25 years of 4,000kWH is 100,000kWH. $25K means $0.25/kWH, which seems high.
    - guimarin 15y ago
      in south san jose, we pay an average of $.42/kWH in the summer. and it only goes down to about $.31 in the winter.
rmason 15y ago
He's making way too many assumptions. In 1894 a writer said that at then current rates of population expansion in fifty years the streets of London would be buried in horse manure. http://www.thefreemanonline.org/columns/our-economic-past-the-great-horse-manure-crisis-of-1894/ http://www.thefreemanonline.org/columns/our-economic-past-th... Course he didn't foresee the advent of the automobile. Breakthoughs like the horseless carriage come out of nowhere. Something like Thorium could end up generating ultra cheap electricity and in fifty years solar might end up being thought of as a quaint technology like buggy whips. Our goal for the US should be energy independence, not a slavic devotion to a specific technology.
- marze 15y ago
  Since solar is less than 1% of US electricity generation, it is unclear why you interpret this to be "a slavic devotion to a specific technology". Solar is the ultimate option of energy independence, since as the OP discusses, 30 lbs of sand turned into solar cells will power a house for three decades or more.
  - temphn 15y ago
    But it's hard to store energy and to transmit it across long distances. This is the fundamental problem with solar and wind. You can put one of China's new thorium [1] or pebble bed [2] reactors anywhere on the face of the earth, and the wattage per surface area ratio relative to solar will be a great deal less. Solar will likely be some part of the answer but it's always going to be niche relative to oil, coal, nuclear, and (where the region allows it) geothermal/hydroelectric. The question that only experts in the space could answer is whether the $1.25 price per Watt is due to a real decrease in the price of fundamental components/manufacturing processes or whether it is due to subsidies of some kind. [1] http://www.telegraph.co.uk/finance/comment/ambroseevans_pritchard/8393984/Safe-nuclear-does-exist-and-China-is-leading-the-way-with-thorium.html http://www.telegraph.co.uk/finance/comment/ambroseevans_prit... [2] http://www.nytimes.com/2011/03/25/business/global/25chinaside.html http://www.nytimes.com/2011/03/25/business/global/25chinasid...
    - 15y ago
nradov 15y ago
Beyond the power price issues there is some value in being able to partially power your residence when the grid is down. Many of the nicer homes in Florida now have fossil-fuel generators since everyone has seen how a hurricane can knock out power for weeks. And grid reliability is likely to decrease due to lack of infrastructure investment.
tryitnow 15y ago
If solar really does drop in price significantly and has a big impact, wouldn't that lessen demand for coal/natgas/etc? A drop in demand will lead to a drop in the price of those fuels everything else held equal. Of course, maybe the declining supplies of fossil fuels will cause fossil fuel prices to rise. But what about advances that make the extraction and consumption of fossil fuels more efficient? I'm just throwing these things out there because there's a lot of economic dynamics that could move targets like "grid parity" significantly.
prodigal_erik 15y ago
How can landlords make this an investment that pay off? http://sfbay.craigslist.org/search/apa?query=solar+panels&srchType=A http://sfbay.craigslist.org/search/apa?query=solar+panels&#3... hardly finds any hits, so I take it "you'll have lower electric bills in this apartment" has not been found an effective way to attract renters.
ck2 15y ago
But the fact that 30 pounds of silicon, an amount that costs $700 to produce, is enough to generate a lifetime of household electricity baffled me. Except per panel is at least $300 and you need a bunch of them. I guess the idea is also to avoid battery storage and just feed the grid. Price comparison for grid-tie http://www.sunelec.com/comparisons_of_grid_tie_systems_prices.html http://www.sunelec.com/comparisons_of_grid_tie_systems_price...
orijing 15y ago
This is really interesting because very recently, a bunch of American solar companies joined together to sue Chinese solar companies for selling panels "below cost" (i.e. "dumping") [1]. I don't understand how that works. What is the cost they use? For industries with steep learning curves, the right strategy would be to use expected future cost as the basis for business decisions, rather than the trailing average (realized) cost, in order to build the market and more quickly progress on the learning curve. If that's illegal (it's often used in instances I mentioned above), then I feel like progress in industries with steep learning curves will be slower, because companies will be more timid, causing the market to grow less quickly. What is everyone's opinions here? [1] http://www.ibtimes.com/articles/234291/20111019/solarworld-solar-panels-cells-china-antidumping-subsidies-lawsuit-complaint.htm http://www.ibtimes.com/articles/234291/20111019/solarworld-s...
- danssig 15y ago
  Personally I wish selling below cost were illegal across the board. It's a destructive practice and allows people who have no stake in one kind of market kill that market. Take the Amazon Fire, for example. They lose money on every unit sold but they don't care because they expect more sales in their real business: retail. How are companies who only make these devices (e.g. Apple) supposed to compete with that? What market are they supposed to use to makeup their losses. And how can they protect this other market from getting hit with the same thing?
  - icebraining 15y ago
    How are companies who only make these devices (e.g. Apple) supposed to compete with that? Apple doesn't only make those devices: see iTunes and the App Store. Besides, one can argue that they do the same in their deal with AT&T (which cuts $100 from the iPad price). But to answer your question, there is more to compete on than price; in fact, Apple knows that well, considering they've been selling Intel laptops with less bang per buck than other manufacturers, like HP and Dell, and still sells a lot.
    - danssig 15y ago
ww520 15y ago
This is fantastic. Haven't looked at the solar pv for couple years. Didn't realize they have dropped so much in price. Does anyone know the current approximate total cost (labor + material) in Northern CA? It was like $8-$10/W last I looked couple years ago. Also how easy is a DIY approach in installation?
- ph0rque 15y ago
  I just got quoted $5.10/W in NC, can't imagine the CA costs are too different.
Havoc 15y ago
>As scale goes up, per-unit costs come down. This is known as a "learning curve" Weird. Where I come from that is called economies of scale & learning curves are applicable only to the labour component.
roel_v 15y ago
Anecdote != data, subsidies are bad, etc etc - but my parents' PV installation is paying off at an 11% ROI right now (Belgium, heavily subsidized), up from an estimated 8% at the time of installation (3 or so years ago) because of the high amounts of sunshine there have been there. Bring on the global warming. There are many people getting filthy rich on these installations (for example those who have large industrial buildings with roof space they don't use - they are getting 4-8% NET YIELD on as much money as they could borrow back in 2006-2007, which back then of course was easy as pie).
icebraining 15y ago
"European solar radiation"? How much is that exactly? I'm pretty sure the radiation levels where I live (Portugal) are much higher than in Scandinavia.
jakeonthemove 15y ago
A fascinating idea is to use solar and wind power to power factories or mining/production sites that are in remote locations - often, that's one of the main limiting factors. The main disadvantage of solar power is that it can't be used 24 hours a day, however besides the expensive batteries, solar power can be stored in other ways - for example, you can use every minute of idle time or free capacity to power compressors that pump air inside a few large tanks, and use that compressed air at night to power the generators.
feb 15y ago
In the article the author claims the price reductions came from technology improvements. But some say they are caused by the entry of the Chinese on the market with heavy subsidies and dumping practices (http://www.grist.org/solar-power/2011-10-19-are-we-in-a-solar-trade-war-with-china http://www.grist.org/solar-power/2011-10-19-are-we-in-a-sola...).

125 points by ph0rque 15y ago

00joe 15y ago

sunelec.com, PV Panels $1.28 Peak watt, Inverter $0.5 watt, Rails and Cables $0.27 watt. In my area I expect to save .18 cents per year per peak watt. Prices have been falling at 1-2 cents a week since june. http://pvinsights.com/ http://pvinsights.com/

droithomme 15y ago

This is true for deep space satellites and locations where running a power line is cost prohibitive, such as weather monitoring stations in Antarctica.

CapitalistCartr 15y ago
It's also true in parts of Florida. In rural areas, PV can be cheaper than paying the power company to run out their lines. I expect, in five years, it'll be worth my while to put them on my house, in the middle of the city.

pingswept 15y ago

I've found Travis Bradford's book Solar Revolution to give a good overview of the solar industry, with the same numerate feel as this article: http://www.prometheus.org/research/solarrev http://www.prometheus.org/research/solarrev The best rebuttal I've heard (to renewables generally, not PV specifically) is the second to last chapter of Matt Ridley's The Rational Optimist: http://www.rationaloptimist.com/books/rational-optimist-how-prosperity-evolves http://www.rationaloptimist.com/books/rational-optimist-how-... (Sorry I can't link directly to the content, but so far as I know, it's not available online in either case.)

Lost_BiomedE 15y ago
Thanks. I will have to get 'The Rational Optimist'. Matt Ridley's book 'Nature via Nurture' impacted me a lot when it first came out. The online course 'Physics for Future Presidents' taught me a lot about how to evaluate energy sources. I would recommend it to anyone interested in learning the physics concepts behind many hotly debated areas, whom currently has little knowledge or exposure in this area.
schiffern 15y ago
As far as Matt Ridley's writing, can you speak to whether these are the same arguments: http://online.wsj.com/article/SB10001424052748703421204576327410322365714.html http://online.wsj.com/article/SB1000142405274870342120457632... ? Summarized, Ridley argues here that the "renewable/non-renewable" distinction is quantitative (not qualitative), and that renewable energy harvesting devices are built from non-renewable materials.
- pingswept 15y ago
  Some of the arguments in that article are repeated in the book, but it's not the main thrust of the chapter I was referring to. I'm afraid I gave the book to my brother after I read it, so I can't give you an authoritative summary of the arguments in the book. As best as I can recall, the argument was renewables generally have such low power density (W/m^2) and high energy cost ($/J) that they are unlikely to be an effective solution to climate change, should climate change be as severe as we fear it might be. (Ridley is not a climate change denier, but he does think scientists' worst fears are exaggerated. Here's an audio interview with Ridley that might cover some of the same stuff in the book: http://www.econtalk.org/archives/2010/10/ridley_on_trade.html http://www.econtalk.org/archives/2010/10/ridley_on_trade.htm...

marze 15y ago

It is surprising how little attention has been created by this huge PV panel price decrease, from $4.00 a watt to $1.25 in three years. Solyndra is an early casualty, since their business model depended on PV panel prices to fall much more slowly. The economics of home based solar electricity depends on three numbers, the panel price, the local retail electric rate, and the interest rate of the loan for the system. Right now, in much of the US, you can see that a PV system makes sense for new construction. A simple example: $12500 : 4500 W PV system w/no storage (grid backed up) 4% interest rate, payment of $60/month $0.11 per kwh avoided cost, the system generates about $70 of electricity/month In a nutshell, this is grid parity, right now in 2011. And the owner of such a system does not need to worry about utilities increasing their rates over the years.

brc 15y ago
Does your example include a FIT (feed in tariff) provided by government at a much higher rate than grid power, or are you doing a calculations at grid power? A lot of places have a high FIT value currently, but this is subject to political whims and any incoming government might find it easy to gain votes by trimming the FIT, as has already happened in many places around the world. Another huge problem with these calculations is the very small fraction of people who stay in one house for more than 10 years. Essentially you have to stay in the house for the entire payback period or you've lost out. Personally I think the solar price will have to drop to the point where it is much lower than grid (with no subsidies), rather than just about equal. At that point, takeup will be much higher.
- compman775 15y ago
  Why would you have lost out? Couldn't you sell the house for more than you could have if you hadn't had solar panels installed?
- marze 15y ago
  No, just avoided cost. Unless your utility drops the rates significantly, the savings are locked in. As far as moving goes, studies show that solar systems increase the value of a house by approximately the cost of the system. Of course, if solar system prices fall as expected, this premium would likely drop also. And the economics are the same for a system where the cost is rolled into a loan during a home loan refinance, an option available to many people now.

ars 15y ago

Too many assumptions. The biggest of course is that that "22%" number will continue despite the fact that "the learning rate has been exceptionally high". Another assumption is that natural gas prices will stay the same, when actually they are going down right now. Not an assumption but rather an omission: He uses a 25 year payback period for solar, but does not include opportunity cost of that money (i.e. how much that money would have brought in interest) over 25 years. Once you include that (and you should) it doesn't look as good. And in any case 25 years is far too long. 10 years is the standard for evaluating payback periods. 6% over 25 years is 4.5 time the base value. So the solar power actually costs 4.5 times as much as he assumes. Even assuming just 3% would give you 2.1 times your cost. Edit: These calculations are a bit off since they assume paying for the standard power all at once at the end, but actually you make payments throughout.

biot 15y ago
He says that $700 worth of solar cells would produce 4000kWh of electricity per year which is what the average family consumes. Over the course of 25 years ("a lifetime of household electricity") had you purchased that from the grid, it would have cost $25,000. Ignoring maintenance, you get $25,000 worth of electricity for an initial one-time investment of $700. Though that's production cost, and excludes installation, maintenance, etc. so likely multiples of that at retail. I think you misread the 25 years as being a payback period.
- anamax 15y ago
  > Ignoring maintenance, you get $25,000 worth of electricity for an initial one-time investment of $700. Though that's production cost, and excludes installation, maintenance, etc. so likely multiples of that at retail. Something is wrong here. Installation is maybe $3k. The typical retail markup is 2x. So, let's call it $5k. 25 years of 4,000kWH is 100,000kWH. $25K means $0.25/kWH, which seems high.
  - guimarin 15y ago
    in south san jose, we pay an average of $.42/kWH in the summer. and it only goes down to about $.31 in the winter.

rmason 15y ago

He's making way too many assumptions. In 1894 a writer said that at then current rates of population expansion in fifty years the streets of London would be buried in horse manure. http://www.thefreemanonline.org/columns/our-economic-past-the-great-horse-manure-crisis-of-1894/ http://www.thefreemanonline.org/columns/our-economic-past-th... Course he didn't foresee the advent of the automobile. Breakthoughs like the horseless carriage come out of nowhere. Something like Thorium could end up generating ultra cheap electricity and in fifty years solar might end up being thought of as a quaint technology like buggy whips. Our goal for the US should be energy independence, not a slavic devotion to a specific technology.

marze 15y ago
Since solar is less than 1% of US electricity generation, it is unclear why you interpret this to be "a slavic devotion to a specific technology". Solar is the ultimate option of energy independence, since as the OP discusses, 30 lbs of sand turned into solar cells will power a house for three decades or more.
- temphn 15y ago
  But it's hard to store energy and to transmit it across long distances. This is the fundamental problem with solar and wind. You can put one of China's new thorium [1] or pebble bed [2] reactors anywhere on the face of the earth, and the wattage per surface area ratio relative to solar will be a great deal less. Solar will likely be some part of the answer but it's always going to be niche relative to oil, coal, nuclear, and (where the region allows it) geothermal/hydroelectric. The question that only experts in the space could answer is whether the $1.25 price per Watt is due to a real decrease in the price of fundamental components/manufacturing processes or whether it is due to subsidies of some kind. [1] http://www.telegraph.co.uk/finance/comment/ambroseevans_pritchard/8393984/Safe-nuclear-does-exist-and-China-is-leading-the-way-with-thorium.html http://www.telegraph.co.uk/finance/comment/ambroseevans_prit... [2] http://www.nytimes.com/2011/03/25/business/global/25chinaside.html http://www.nytimes.com/2011/03/25/business/global/25chinasid...
  - 15y ago

nradov 15y ago

Beyond the power price issues there is some value in being able to partially power your residence when the grid is down. Many of the nicer homes in Florida now have fossil-fuel generators since everyone has seen how a hurricane can knock out power for weeks. And grid reliability is likely to decrease due to lack of infrastructure investment.

tryitnow 15y ago

If solar really does drop in price significantly and has a big impact, wouldn't that lessen demand for coal/natgas/etc? A drop in demand will lead to a drop in the price of those fuels everything else held equal. Of course, maybe the declining supplies of fossil fuels will cause fossil fuel prices to rise. But what about advances that make the extraction and consumption of fossil fuels more efficient? I'm just throwing these things out there because there's a lot of economic dynamics that could move targets like "grid parity" significantly.

prodigal_erik 15y ago

How can landlords make this an investment that pay off? http://sfbay.craigslist.org/search/apa?query=solar+panels&srchType=A http://sfbay.craigslist.org/search/apa?query=solar+panels&#3... hardly finds any hits, so I take it "you'll have lower electric bills in this apartment" has not been found an effective way to attract renters.

ck2 15y ago

But the fact that 30 pounds of silicon, an amount that costs $700 to produce, is enough to generate a lifetime of household electricity baffled me. Except per panel is at least $300 and you need a bunch of them. I guess the idea is also to avoid battery storage and just feed the grid. Price comparison for grid-tie http://www.sunelec.com/comparisons_of_grid_tie_systems_prices.html http://www.sunelec.com/comparisons_of_grid_tie_systems_price...

orijing 15y ago

This is really interesting because very recently, a bunch of American solar companies joined together to sue Chinese solar companies for selling panels "below cost" (i.e. "dumping") [1]. I don't understand how that works. What is the cost they use? For industries with steep learning curves, the right strategy would be to use expected future cost as the basis for business decisions, rather than the trailing average (realized) cost, in order to build the market and more quickly progress on the learning curve. If that's illegal (it's often used in instances I mentioned above), then I feel like progress in industries with steep learning curves will be slower, because companies will be more timid, causing the market to grow less quickly. What is everyone's opinions here? [1] http://www.ibtimes.com/articles/234291/20111019/solarworld-solar-panels-cells-china-antidumping-subsidies-lawsuit-complaint.htm http://www.ibtimes.com/articles/234291/20111019/solarworld-s...

danssig 15y ago
Personally I wish selling below cost were illegal across the board. It's a destructive practice and allows people who have no stake in one kind of market kill that market. Take the Amazon Fire, for example. They lose money on every unit sold but they don't care because they expect more sales in their real business: retail. How are companies who only make these devices (e.g. Apple) supposed to compete with that? What market are they supposed to use to makeup their losses. And how can they protect this other market from getting hit with the same thing?
- icebraining 15y ago
  How are companies who only make these devices (e.g. Apple) supposed to compete with that? Apple doesn't only make those devices: see iTunes and the App Store. Besides, one can argue that they do the same in their deal with AT&T (which cuts $100 from the iPad price). But to answer your question, there is more to compete on than price; in fact, Apple knows that well, considering they've been selling Intel laptops with less bang per buck than other manufacturers, like HP and Dell, and still sells a lot.
  - danssig 15y ago

ww520 15y ago

This is fantastic. Haven't looked at the solar pv for couple years. Didn't realize they have dropped so much in price. Does anyone know the current approximate total cost (labor + material) in Northern CA? It was like $8-$10/W last I looked couple years ago. Also how easy is a DIY approach in installation?

ph0rque 15y ago
I just got quoted $5.10/W in NC, can't imagine the CA costs are too different.

Havoc 15y ago

>As scale goes up, per-unit costs come down. This is known as a "learning curve" Weird. Where I come from that is called economies of scale & learning curves are applicable only to the labour component.

roel_v 15y ago

Anecdote != data, subsidies are bad, etc etc - but my parents' PV installation is paying off at an 11% ROI right now (Belgium, heavily subsidized), up from an estimated 8% at the time of installation (3 or so years ago) because of the high amounts of sunshine there have been there. Bring on the global warming. There are many people getting filthy rich on these installations (for example those who have large industrial buildings with roof space they don't use - they are getting 4-8% NET YIELD on as much money as they could borrow back in 2006-2007, which back then of course was easy as pie).

icebraining 15y ago

"European solar radiation"? How much is that exactly? I'm pretty sure the radiation levels where I live (Portugal) are much higher than in Scandinavia.

jakeonthemove 15y ago

A fascinating idea is to use solar and wind power to power factories or mining/production sites that are in remote locations - often, that's one of the main limiting factors. The main disadvantage of solar power is that it can't be used 24 hours a day, however besides the expensive batteries, solar power can be stored in other ways - for example, you can use every minute of idle time or free capacity to power compressors that pump air inside a few large tanks, and use that compressed air at night to power the generators.

feb 15y ago

In the article the author claims the price reductions came from technology improvements. But some say they are caused by the entry of the Chinese on the market with heavy subsidies and dumping practices (http://www.grist.org/solar-power/2011-10-19-are-we-in-a-solar-trade-war-with-china http://www.grist.org/solar-power/2011-10-19-are-we-in-a-sola...).