Solar Panels and the Quest for $1/Watt
If solar panels cost $1/watt, you can sell them (installation included) for $2/watt. Coal (installation included) costs $2.10/watt. To date, solar is still reaching to compete with coal, but the margins are closing. To (over)simplify how this works, you need to ignore issues like subsidies, qualitative costs, or kinks in the supply chain, and boil it down to money. Two hurtles that must be jumped before photo voltaic solar cells become cheaper than coal: efficiency and production cost. Fortunately the solar industry has already made important gains in both. Today, we’re going to talk about two types of solar panels: silicon and thin-film, and solar’s quest for $1/watt.
Silicon Solar Panels
Silicon panels are the most recognizable form of solar, in part because they’ve been around the longest. Unfortunately, until the end of 2007, they’ve always had some issues with cost. Popular Mechanic summarizes this much better than I could:
“Traditional solar cells require silicon, and silicon is an expensive commodity (exacerbated currently by a global silicon shortage). What’s more, says Peter Harrop, chairman of electronics consulting firm IDTechEx, “it has to be put on glass, so it’s heavy, dangerous, expensive to ship and expensive to install because it has to be mounted.” And up to 70 percent of the silicon gets wasted in the manufacturing process. That means even the cheapest solar panels cost about $3 per watt of energy they go on to produce. To compete with coal, that figure has to shrink to just $1 per watt.” – courtesy of Popular Science’s Michael Moyer
To clarify on that statement, the global silicon shortage has eased slightly, but supplies are still tight so the price of silicon is still relatively high. The bonus behind silicon solar panels is efficiency and lifespan. Silicon panels tend to be about 20%-27% efficient, reliable, and they last for over twenty years. That means with silicon panels you earn the cost of your investment back in the long term. Depending on where you live and what kinds of panels you buy, “long term” can mean 10-40 years. With cheaper solar panels, obviously, you would regain your investment sooner.
B.P. Solar offers a calculator to estimate your solar panel investment based on location, solar system, and home energy use. Just keep in mind that their calculator can’t adjust for fluctuating variables like energy costs, public policy, or B.P.’s competition; it’s a ball-park estimate at best. Divide the total cost by annual energy savings to calculate your return-investment time frame. (Mine was 35 years in an inefficient house)
In order to approach the magic $1/Watt goal, solar producers have tried new manufacturing techniques to reduce waste, boost efficiency, and lower prices. 1366 Technologies aims to come close to the $1/watt mark. They want to innovate manufacturing processes to reduce cost without sacrificing efficiency. With some investment money in their pocket, they’ll be working hard to bring their silicon panels to market in the future. Until then, or until more government support crops up, traditional solar panels are still best reserved for commercial (buy in bulk) and long-term investment.
Thin-film Solar Panels
These days thin-film technologies are all the rage in the solar industry. The benefit of thin-film solar technology is cost. By cutting the silicon out of the equation, companies remove a huge price barrier. One of the issues with thin-film technology is that it tends to be less efficient with a shorter lifespan. A new thin-film record was recently set at 19.9% efficient, which matches silicon panels. But unlike silicon solar, in this field the $1/Watt barrier has been successfully breached. Two companies can boast the achievement:
Nanosolar has already begun production of their famed solar product, which uses an innovative printing technology. They literally print the solar panels onto sheets of metal, like ink on paper. This technique allows for mass-production at an 80% reduction of manufacturing cost. They didn’t just reach the $1/watt mark, they surpassed it. Even the Department of Energy agrees: they compete with coal. For now, Nanosolar is sold out into the foreseeable future. In time we’ll no-doubt see their products become increasingly common as they diffuse through the solar market. So what’s the catch? Critics point out that the technology relies on indium, which has a finite supply. You can read some interviews, or watch a video for more information.
AVA Solar Inc. is another forerunner as they prepare to mass-produce their stream-lined solar panels. Their technique requires fewer raw materials, causes less waste, and maintains high efficiency–11%-13%. At under $1/watt, AVA Solar has nearly completed a production facility to mass-produce their technology. They promise “efficiency and stability performance comparable to the leading CdTe-based modules currently on the market” –CdTe is cadmium telluride, a popular thin-film composition. Kudos go out to Professor W.S. Sampath at Colorado State for helping to bring this technology to market.
The demand for either type of technology is high – and likely to keep rising. To draw from an example , Southern California Edison recently decided to invest in 65 million square feet of commercial roof space for solar panels. Check out these graphs for information spanning the past decade. Solar technology has entered the game with fossil fuels at a time when the technology has not yet reached its limits, as these recent innovations and improvements attest. Unfortunately, it will probably be years before solar starts to reach its full potential. Even without constrictions of silicon supply, building the production base will take time. When (not “if”) photo voltaic solar starts to compete with coal on a large scale, it will be interesting to see how the older, entrenched industry reacts. As oil falls out of favor, the coal industry sees an opportunity to expand, despite growing opposition to green house gases.
But let’s be fair; P.V. solar is not the silver bullet to clean energy. Even the most efficient, affordable solar panels or films can only operate under the sun, and they require batteries to store excess energy. That means P.V. solar works well during peak hours, when people are awake and using all their electric gadgets and appliances, but at night or in higher latitudes, more options are necessary. Other solar technologies like solar-thermal could pick up the slack. Solar thermal is experiencing its own revival, but all technologies come with their pros and cons.
So we turn to other energy sources: consider wind, geothermal, algae fuel, or wave power. Each has the fundamental benefit of using renewable resources–energy that will never run out. In contrast, what is the weakness of fossil fuels? Extraction of a finite resource with pollution as a byproduct, culminating in powerful contributions to climate change. Which limitation would you choose in a technology? Infinite or finite source? What byproduct would you bet on? Equality of cost is coming in the energy industry; for P.V. solar it is already here.
Extra Sources:
Solar Efficiency Graph via the Department of Energy.
Image courtesy of Flickr
You Might Also Like
Native American Tribe Going for Solar, and Money
1st World Ranking of Clean Energy Technology (CET) Sales — CET to Become 3rd Largest Global Sales Sector by 2020
Clean Tech Private Equity Firm Reaches & Exceeds $1 Billion Target for Clean Tech Fund!
Asia Light Years Ahead of the US in Clean Tech Investment — Financial and Economic Consequences
April 1st, 2008 at 2:15 pm
Solar Panels and the Quest for $1/Watt | nerdd.net…
\r\nGood overview of the solar industry\r\nThe demand for either type of technology is high – and li…
April 2nd, 2008 at 5:00 pm
Michele,
Good article, but I think you’ve been drinking the NanoSolar PR kool-aid. There are a couple of exaggerations there..
- Nanosolar hasn’t produced anything yet. They are still building a factory, and haven’t proven their ability to mass produce CIGS at any scale, and for low cost. Same for AVA. Their $1/Watt claims are vaporware until they actually start producing.
- CIGS hate water – therefore, to be effective for PV Solar, they need to be encased in something transparent and waterproof. The only thing that fits that bill is glass (plastic will absorb water over time). So, it has the same problem as “traditional solar”.
Not trying to totally bash thin-film, but it’s still going to be awhile before it gets to $1/W.
April 3rd, 2008 at 7:43 am
This is a very nice article. I’d like to make a few comments to augment some of your points.
First Solar is, I believe, a publicly-traded company that makes CdTe-based PV panels, and these are available in many commercial products (I have no connection to them).
Polysilicon manufacture for traditional silicon PV panels is big business in China, and it was recently exposed in a Washington Post article to be badly damaging the environment and population of rural China because of failure to follow basic waste treatment plans. This is discussed in an article I wrote for Blogcritics Magazine (blogcritics.org)and on my own blog. So, though certainly I stick up for solar energy, we must stop purchasing these products until China cleans up its act. They are committing murder in the countryside.
I certainly agree with your comment that a mix of energy production methods is needed, including wind and solar heating. However, I don’t think that it is a weakness of PV solar cell methods that sunlight is cyclical and energy must be stored. I think it is worthwhile looking at solar vs. coal here: coal electricity plants run flat out all the time, or suffer major efficiency problems. Is that better than solar cells? I don’t think so. Electricity still has to be stored or it gets wasted, and the pollution from coal is significant, as you know.
So, I think my view is a bit more optimistic than yours about solar PV technology. I don’t think that Nanosolar can be criticized for using Indium in their solar panels. The panels have to be made out of something. Also, Nanosolar uses so little material in its thin films that I think they have potentially great technology. Whether it will compete with First Solar remains to be seen in the marketplace.
We definitely need higher production capacity for these new PV technologies, and we need to pressure China on the polysilicon (polycrystalline silicon) manufacturing practices.
Thanks for the terrific and timely summary! Jim
April 3rd, 2008 at 11:07 pm
James,
Thank you for the wonderful comment. I have some thoughts and replies for you, which I will post on your blog and highlight here:
You’re absolutely right to mention China and the Washington Post article. I too was appalled when I read it. Your article describing the high-and-mighty status of factory managers, and the effects of their illegal dumping are both disturbing and sobering. The solar industry’s future is bright, but like any industry, efforts must be made to ensure that the benefits inherent are not mitigated by incidents like those in the Henan Province, or others yet to be discovered.
I admit that I omitted First Solar despite its success and reputation in the industry. Perhaps it was a poor decision on my part, but to my knowledge they are not producing solar cells at or under $1/watt. If they are, in fact, selling their products at the magic price, I’d love to know!
As for the benefits of solar power over coal, I wholeheartedly agree, but I do wish that battery technologies were farther along to offer more options to the solar industry. Other industries (auto) would benefit as well.
One reason I fancy solar-thermal is because it stores excess energy as heat, which is much more efficient. Cleantechnica has several articles on that topic, including one relating solar-thermal to coal.
Lastly, Nanosolar and indium. That’s a tough one because some projections claim indium supplies will run out within the decade. However, given Nanosolar’s competitive thin-film cells, I’d fall short of actually criticizing them at this point. Their product, and First Solar too, will help wean us off of carbon-based energy production, which we agree is a necessary step for the near (immediate?) future.
You can read James Bashkin’s article and blog here
April 3rd, 2008 at 11:20 pm
Craig,
Good points. However, the most recent article I read about Nanosolar was about their first manufacturing plant coming online in December. They’re currently shipping panels to generate 1MW for Beck Energy in Germany. However, time will tell how well their printed technology handles real-world long-term conditions.
You’re right about CIGS and water; it’s one reason their efficiency decreases over time. $1/watt refers to manufacturing of the cells, but *installation* usually ends up around $2/watt because of the issues you raised. Nevertheless, coal-based power plus installation costs slightly more – $2.10/watt.
Haha, you’re also right in that I’m pretty excited about Nanosolar in general. Maybe they’ll pay me for the positive publicity!
April 4th, 2008 at 4:15 pm
Thanks for your kind and detailed response, both here and on my blog.The points in your comment are excellent ones. I hope I didn’t sound too critical in my blog- I really liked your article and simply wanted to augment it with a few things that I’ve read about, and in some cases written about, recently. I agree with your comments about the unfortunate situation in China. It is particularly frustrating that some of China’s richest people are running these terrible businesses- I’m sure they could afford to do better.
Your reasoning behind your choices, which you kindly explained in your comment above, makes a lot of sense. I agree with you entirely that solar-thermal energy is an excellent way to improve the sustainability of our energy supply. I have absolutely no argument with it and, in fact, I wrote strongly in its favor in a couple of recent discussions at the social network Gather.com.
I certainly can’t argue with your wish that battery technology had come further, either. However, I have read about enough examples of real electric cars being made and used, and about things like running homes off of electric car batteries* at night, that I don’t feel the technology to be overly flawed. In fact, I just read that Denmark* has so much extra wind-power capacity that they are going to set up a national program for charging electric cars with that capacity. But, again, you are right that we can’t gloss over the issues that battery disposal and lifetime introduce. I believe these issues are quite significant, but also that they are much more manageable than the waste from coal or nuclear power. So, I think we are really agreeing on all but the smallest details, in a sense, though the details are important.
I haven’t seen a $1/Watt claim from First Solar, either. However, since the technology is based on CdTe, I made the intuitive (but not necessarily correct) leap that AVASolar’s technology would be similar because it, too, will be governed by the physics of CdTe. That, and the fact that I had taken some heat in earlier articles for ignoring such an established company as First Solar in favor of the relatively young Nanosolar, made me sensitive to simply bringing First Solar into the discussion. I am particularly impressed with companies that actually manage to implement their new technology on a significant manufacturing scale because there are so many barriers, technical and financial and otherwise (I think I wish that I didn’t have such a good appreciation of this problem …
.
Regarding your final point about Nanosolar and Indium, I have no special knowledge (at this moment- I think I’ll look into it because it seems important), and I think the tone of your comment is right on target. We need to shift away from carbon-based fuels, and we need to use reasonable methods to do so. All of the solar panels we have discussed seem reasonable or better, though they may be supplanted by other approaches sooner than I expect, out of necessity or invention, or both.
It is very kind of you to link to my blog, and I am most grateful. I have linked to your Cleantechnica article both on the blog (the “read more” link) and in a republished version* at Gather.com. There is considerable discussion at the Gather site. I look forward to exploring other articles on the Cleantechnica site, and to following your work.
Best wishes, Jim
*
http://www.gather.com/viewArticle.jsp?articleId=281474977240547&nav=Namespace
http://www.metaefficient.com/cars/danish-drivers-to-fill-their-tanks-with-wind-power.html
http://www.gather.com/viewArticle.jsp?articleId=281474977300649&nav=Namespace
April 4th, 2008 at 4:21 pm
Craig and Ms. Bennett:
I don’t think we have to assume that glass is required for the Nanosolar devices, though the lifetime of the devices would be less with most other coatings. I suspect that there are good polymer coatings that would work pretty well (or better). Otherwise, I don’t think that companies could be making the claims we read about solar inks and paints.
I actually typed my website address correctly this time! Best wishes.
April 4th, 2008 at 6:00 pm
My reading of the indium situation and yours differ.
The problem seems to be that there was low demand and extraction rates were low. A difference between current market supply and potential supply.
Quite analogous to the shortage of PV quality silicon while silicon is one of the most plentiful materials in the Earth.
“ICA also notes that the indium metal supply for mid and long term views, quoting US Geological Survey data in 2004, shows that indium is plentiful in the earth’s crust in quantites approximately three times that of silver with 1.8trillion tons reserve silver and 5.4trillion tons for indium.”
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VM5-4FWNBMF-Y&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=66cdfcbc84ac750a10cb05a472cf65b7
April 4th, 2008 at 6:52 pm
Every body keeps forgetting our congress and president, past and future choices are heavely invested in the oil,gas and coal industry as well as the defence contractors. We will continue to use oil,gas and coal and submit our children to any meat grinder they create any where in the world. As stock holders they are making a killing at their constituents expence.
We need new people in congress that are involved in the clean tech areas. Then and only then will we see a new and cleaner world. If we keep voting for the same people we will keep getting the same results.
April 4th, 2008 at 11:00 pm
Thanks, Bob. Now I don’t have to search for the info!
April 5th, 2008 at 12:49 pm
James,
Thanks for your wonderful reply! I’m always excited to get feedback and comments on my articles. Lets me know someone’s out there reading and thinking about them.
Ah the details. Don’t they say “The devil’s in the details”? I admit that my technical understanding of CdTe is limited, other than the facts associated with the technology. I still need to dig deeper because “cadmium” raises a few red flags for me. Paired with the incident(s?) in China, it makes me wonder if there are risks involved with using a potentially harmful heavy metal to provide renewables. Any comments on that front? Perhaps my laps in knowledge is due to issues that have already been settled?
April 5th, 2008 at 12:54 pm
Just Watching,
Well I wouldn’t say “forget”. In fact I’ve touched on that topic before. I think that as renewables become more financially tempting, they’ll lure investment away from more entrenched industries. In fact it seems that announcements of multi-million or even -billion dollar investments in renewable companies are made every week. Sometimes several times a week. That’s big news. Also, I think James has written (or mentioned?) banks that are refusing to fund carbon-based ventures because of “future risk”.
As for the Congress and President, it’s true we don’t have an ideal commander and chief. But let me remind you that Congress was ready to try and pass a bill to remove oil subsidies and hand them over to renewable energy – until the President swore to veto. They compromised and watered down the bill to get *something* passed, in part because they know his days are limited.
April 5th, 2008 at 1:02 pm
Bob,
Thanks for the link and information! I’m not sure where the disparity in your link and my link came from, but I’ll try to look into it. Unfortunately my link didn’t give a *reason* for their estimates…
Oh! And speaking of China and solar technology, there’s a problem: “Waste from indium plants to the river, the local source of drinking water, is threatening water for more than 100,000 people, a newspaper in Zhuzhou has claimed.”
Oh how bitter, I’ve found another example of the cost of renewable technologies in China.
April 8th, 2008 at 2:38 am
This is a very info rich article about solar energy, thanks, Bob. Absolutely, the solar energy will be one of solutions for current environment problems and energy crisis.
April 23rd, 2008 at 10:45 am
Hey People i read your last post on solar cells and solar film and done research of my own and found nother name to add to the list of companys making solar film, and thought id share it with you all.
http://www.konarka.com/
April 23rd, 2008 at 3:37 pm
Thanks Joshewa
May 22nd, 2008 at 5:46 pm
If you do the math photovoltaics can produce gas equivalent of 180,000 gallons per acre, while bifuels like 100. This not not include the fuel to seed and harvest the fields. Sunpower 3rd gen, will be producing power at 20 watts per square foot (22% efficient) in a couple years. Those nanosolar panels sure look beautiful. A law needs to be passed requiring all new homes to have over 50% of their foundation area covered in PV. That will provide the seed money. An electric prius gets 250 W-Hr per mile. Thus a 5000 Watt system will drive a car 100 miles. At $1 a watt as nanosolar proved, for $5000 investment and a $200 DC-DC charge controller, could drive your car 36,500 miles a year, or drive about 3 cars in your household. At 36.5 miles a gallon, 1000 gallons of gas would be needed, or about $4000. Thus, in about one year the pv system will pay for itself.
May 23rd, 2008 at 6:32 am
@ Bill,
Wow, thanks for the great comment! I’d love to see cars with solar panels on their roofs in the near future, but of course the big concern is cost. Electric cars (or perhaps a hybrid like the Prius) recharged with solar panels at home base would be even better. I’m glad to see people out there who are better at understanding and calculating the math than I am!
June 15th, 2008 at 10:44 am
I believe that mirrors are the only way to solve the twin problems of global warming and death by oil depletion. Not only is (solar thermal) more effecient, it reflects that bright part of the sky next to the sun back into space. On the (very) large scale needed to displace coal and oil, this would make up for the loss of reflectivity due to melting glaciers. It would also create millions of new jobs thus helping the economy deal with higher energy prices…
PV has to be dark in color to absorb and convert light, Imaging seeing black deserts from space, no good…
June 16th, 2008 at 5:50 am
@ FireofEnergy:
While I agree with you in principle, I also think that solar thermal is efficient enough that we wouldn’t need *quite* that many installations to power the globe. While the mirrors will reflect the light that hits them, it’s a relatively small amount of sunlight in the grand scale of things. However, I definitely agree that these technologies will be a big part in getting us off oil and coal. Solar thermal in particular because you can store heat very easily and use it later, like at night.
June 17th, 2008 at 5:24 pm
[...] Can it Replace Coal, Gas, and Oil? Senate Coalition Introduces Clean Energy Tax Package Solar Panels and the Quest for $1/Watt Clean Energy Intro: Solar Businesses 4 Things to Consider Before Going [...]
July 21st, 2008 at 12:33 am
[...] The Solar Quest for 1$/kwh [...]
August 28th, 2008 at 2:41 pm
Yes it looks like Michelle got taken by the Nano Solar sales promotion bug. There are some gaping holes in her logic and story. Note also the omission of the First Solar Corp. juggernaut, that also fits the Nano Solar strategy to ignore reality. Try describing the truth some time with First Solar’s continuation of 50% profit margins, annual doubling of real production capacity, market valuation, and the only realistic assault on $1 per watt in the industry with the production juggernaut to go with it. Everything else is just Popular Science wishing.
December 23rd, 2008 at 2:01 am
Oh,Yeah? “$1/Watt barrier has been successfully breached. Two companies can boast the achievement”. Eh, correct me if I’m wrong, There is NO COMPANY in the world, that is selling $1 a watt panel to the general public. Your hype and representations are worse than president bushes. Oh! I love you articles and all. I don’t blame you for reporting on all the companies bogus claims and vaporware. I am truly a fan. Could you write a piece on where I (we) can get these $1 a watt panels, please. That’s OK I know you can’t, in spite of how many times you report that there are. SS
September 19th, 2009 at 12:10 pm
a project cost for 40 acers land on turnkey also intrested in delarship
November 30th, 2009 at 11:50 am
[...] Can it Replace Coal, Gas, & Oil? Wall Street Cools on Coal – Along With the American Public Solar Panels and the Quest for $1/Watt Air Force Will Be Coal-Powered by [...]
November 30th, 2009 at 12:02 pm
[...] Can it Replace Coal, Gas, and Oil? Senate Coalition Introduces Clean Energy Tax Package Solar Panels and the Quest for $1/Watt Clean Energy Intro: Solar Businesses 4 Things to Consider Before Going [...]
November 30th, 2009 at 12:07 pm
[...] Can it Replace Coal, Gas, and Oil? Senate Coalition Introduces Clean Energy Tax Package Solar Panels and the Quest for $1/Watt Clean Energy Intro: Solar Businesses 4 Things to Consider Before Going [...]
February 14th, 2010 at 4:04 pm
[...] the dynamic layers through low-cost methods, similar to the method NREL is already developing for “printable” thin film solar cells. Another cost savings could be achieved by printing the electrochromatic film on plastic instead [...]