Solar energy has emerged as one of the most viable forms of renewable energy. But to make it even more prevalent and a standard part of power grids, solar-energy harvesting technologies need to perform at a higher level, achieving more efficiency, or a higher ratio of electrical output to the incident energy in the form of sunlight. Manufacturing the cells also must become more cost-effective and less labor-intensive to further promote their widespread use.
Click on the image below to check out some of the latest ways researchers are working to improve the performance and manufacturing of solar cells.
A group of German and French scientists at the Fraunhofer Institute for Solar Energy Systems ISE, Soitec, CEA-Leti, and the Helmholtz Center Berlin recently set a new world record in efficiency of 44.7 percent in a solar cell. They achieved this percentage with a four-junction solar cell that took them three years to develop. The solar cell is comprised of four solar subcells based on III-V compound semiconductors for use in concentrator photovoltaics. (Source: Fraunhofer Institute for Solar Energy Systems ISE)
"Solar energy has emerged as one of the most viable forms of renewable energy. But to make it even more prevalent and a standard part of power grids, solar-energy harvesting technologies need to perform at a higher level, achieving more efficiency, or a higher ratio of electrical output to the incident energy in the form of sunlight."
Exactly Elizabeth, we had been facing this issue for a long time and affecting ROI too. More power from less panels are important, I mean increasing the efficiency of panels. If am not wrong only 40% of the sunlight is able to convert in to energy and rest is wasting
Last time I checked, solar PV was the most expensive from of green energy, by a long shot. The levelized costs of solar PV were only exceeded by solar thermal and off shore wind. Less expensive PV panels will help, but it seems like it will need to be more than just incremental efficiency increases.
"Last time I checked, solar PV was the most expensive from of green energy, by a long shot. The levelized costs of solar PV were only exceeded by solar thermal and off shore wind. Less expensive PV panels will help, but it seems like it will need to be more than just incremental efficiency increases. "
SesmoAndrew, I won't agree with that statement. As per my knowledge, it's the cheapest form of natural/green energy when compare with wind mills and hydro-electric systems.
I think 2014 will be a breakthrough year for solar technology. All of the evidence points to not only improved efficiency out of existing solar-cell technology but also new materials and ways of designing cells that will further improve how they work.
While I applaud the effective increase in the cells, It needs one more thing, not directly but for the Grid to work with Solar.
MASSIVE STORAGE. Roughly 2X the output minimum to cover times of darkness and low output due to weather.
Without said storage the Solar must still be backed by spinning conventional power plants burning fossil fuels. Even just idling those plants is a very expensive situation. Labor to monitor them is a major cost in itself.
And until we have massive storage they must run, day and night, every day.
Solar and Wind pushers have never covered this aspect but it is paramount. Without Storage, both those generation systems cannot be a primary source of power.
Admittedly, in some areas such as the Southwest US, Solar comes when the power demand is peaking, so that helps there. But here in the Northeast it is exactly opposite, Most power is consumed in Winter (low influx hours/day) at night, heating homes. For us, Storage must exceed production of solar by 3X to 4X minimum. Low influx and High night demand will drive this.
Solar IS predictable using cloud and weather data.
We already have peaking generators to deal with changes in load, Germany and other countries are distributing these generators to run off wastes, and co heat the local buildings. Gas turbines are the cheapest backup generators and at most add .5 cents per KWH to solar and wind.
But we could use a replacement for traditional spinning reserve which eats up a lot of power for nothing.
The ideal replacement is parked EVs, and used EV batteries, which have 75% of their original storage capacity. . It's already being done, and it save money and fuels sol oar and wind or not.
http://www.wecc.biz/Standards/Development/wecc0044/Shared%20Documents/Posted%20for%20OC%20Approval/Drafting%20Team%20Report.pdf frequency responsive reserve is what cars to grid can do, not just spinning reserve
http://apps1.eere.energy.gov/tribalenergy/pdfs/course_wind_milligan1.pdf agree no new generators needed because of wind
No Storage needed at all.
Yes we need backup and peaking generators, they can run on waste fuels. We only need the expected max LOAD, it has nothing to do with the peak solar and wind. In practice, we need 50% of our max load, because we have load shedding agreement with big, big interruptibility energy users for the extremely rare instances of not enough solar wind and backup.
Wikipedia is not a valid Backing for data, anyone can post anything there.
You want to convince me , Get a paper published by a university or major company in the field of energy production.
And you miss my point entirely, Yes, I admit SUNNY areas can benifit.
You miss the point that MOST of the USA is NOT considered Sunny !!!
It has been below freezing for the entire last month here. Overcast and snowing for a lot of that time. SOLAR CANNOT COMPETE HERE.
And If Every Electric Car in the country were plugged in, I expect that would power the grid for about 5 minutes, then all those folks could walk to work because the batteries would be flat. They plug them in to Charge Up, not power the grid, you are expecting the power to flow the wrong way, last I checked (long ago), it wasn't possible to do that.
And they can't charge during the daytime, last I checked, there was precisely one public charging station in the entire state. It's over in the State Capitol. That's a two hour drive from here, which is outside the range of most electric cars anyway. As far as the Expended batteries, Just how many of those do you think exist at this point, I do not expect it's enough to matter yet.
Oh, and where are the power companies supposed to keep them?
But feel free to spread your opinion, I spent a career in the Military to ensure you have that right.
I will stick to Facts, such as those quoted below you by Charles.
I Like Hydro-Electric for the Record. It's clean, relatively cheap and runs 24/7/365. No backup needed. Where I grew up in Colorado, Lots of power came from that. But more came from burning Coal to drive steam turbines. That is still the power of preference there. (Also a low solar influx there)
The German data is correct, solar is peaking summer ac power.
If Germany is sunny enough, most of the world is too.
Solar panels for snowy areas are at high angles, have a slick surface, so snow slides off, and panels work through as much as 2 inches of snow.
Solar is not at it's best in the winter, obviously. No one source will supply our needs. solar, wind backed with waste fuels in backup generators, particularly CHP local generators which provide heat as well, CAN.
Why don't you read the article or look up vehicle to grid, it's a scholarly article from a university. The batteries eliminate frequency reserve spinning reserve with nearly zero wasted power, and give the backup turbines the 15 minutes they need to ramp up. Using only 2% of the battery, and recharging right after that, at a profit for the vehicle owners, and savings for the utility companies. cars spend 95% of their time parked.
Lots of companies have charging stations in their parking lots, and obviously more will as it becomes more popular. I never said pure electric, I assume plug in electric hybrids that can go as far as any car. some 90% of passenger car trips are less than 30 miles. That's all electric for as hybrid like the Volt.
Power companies have massive amounts of land, that's really not a problem, remember they are only for a few minutes at a time, not hours, not days, that what waste fuels in existing turbine are for.
Thanks for risking your life to defend the country, that has nothing to do with this discussion.
Do your own math. Solar panels now cost 50-70 cent on the world spot market, less than 2$ installed in Germany and sometimes in the USA for large systems. They last over 30 years. Not 15, not 20.
The DOE, the old atomic energy Commissions, still 90% nuclear related activities, doesn't even calculate solar cost themselves, they used SolarBuzz, that assumes 15 year life and batteries. Sadly, nearly everyone just uses the DOE numbers.
The DOE is oriented towards big energy companies and solution, they don't even count residential.
Is it so hard to believe they are captive to the fossils and nuke industries? You know the USA, best gov money can buy. Reading the DOE/EIA annual reports is a joke, it's in Thermal BTU's, it doesn't even break out wind and solar, and does not reference their numbers and assumptions.
http://www.eia.gov/oiaf/aeo/assumption/pdf/renewable_tbls.pdf Really? It will take the USA till 2035 to come close to Germans solar cost now? And try to find the reference assumption for solar. They won't even let you cut and paste from the document. Please, show me what cost of panels, what lifetime, and storage that the DOE/EIA use for the calculations. They have hidden really well.
Yes, batteries will help solar be even better, but it's not needed.
Spectrolab, a Boeing company, is making and selling 38% and 44% concentrator cells to the space market. They have very high reliability. I think it's just markets. They don't want to compete with cheap panels till they have to. They are expanding and decreasing manufacturing costs. But why would they want to fight the US gov promotion of fossils and nukes, the utility attacks on solar, and the cheap Chinese panels? They own the military space market.
If our gov would stop propping up the fossils and nuclear industries and start really energizing the solar, wind and waste to fuels industries we would make the transition to renewables much faster.
Besides there is no shortage of rooftops and parking lots for existing solar to supply more electricity than we currently know what to do with. More efficiency is a red herring, it's a marginal benefit.
Germany is paying it forward. They are putting their money into solar, wind and waste to heat electricity and fuels. Instead the USA is still plowing money into fossils and nuclear and keeping the prices artificially low and delaying the switch to ultimately cheaper renewable power.
Here's a rebuttal of the De Spegal and NY times articles. http://cleantechnica.com/2013/09/20/new-york-times-gets-big-red-f-germanys-renewable-energy-transition/
Did you think the fossils and nuclear industries would go quietly?
They don't like losing out to solar and wind, is that a surprise? They the core of their argument: it's really rough on their industry.
Gas turbines ramp up and down just fine, that's why they are used for peaking and backup, but the companies that own them, don't make as much money if they are not used all the time. Same for Hydro.
Hydro kills fish, and there is very little available new hydro in the USA. Maybe the underwater turbines will pan out, but not yet.
I did not know about this company Spectrolab, Trenth. That is really interesting to me. I will have to look into it. If this sort of technology can trickle down to the more mainstream markets as well that would be a real breakthrough.
""Spectrolab, a Boeing company, is making and selling 38% and 44% concentrator cells to the space market."" Really you are going to try to make a conspiracy because the space bases cells are more efficeint. Well if i must explain common sense then lets do it. With a space cell it is optimized for a very different enviroment then an earth based cell plus cell cost is not important light and high power is they do not think twice of have a 10% gain in power that costs 2000% more. Space cells do not need to worry about over heating, hail, wind, snow load, bird droppings, oxidation, corrision, need I go on.
Agreed, ramjet. Engineers at Argonne Labs and at MIT have told us that storage will be needed if renewables exceed somewhere around 15%-30% of our overall power. The number is flexible because no one knows for sure until we get there. But I tend to believe the people at Argonne and MIT.
Hi Charles, these figures are bandied about globally by some governments and pretty much all providers, so either they have merrit or someone dreamt up the figure and everyone is jumping on that bandwagon that it suits. I only make this last statement for readers to remember that there are a lot of people that don't do their research properly either for convenience or laziness.
Anyhow over to other aspects of this, I've seen figures quoted higher than 30% for PV panels for maybe 10 years or more but the panels actually being sold never seem to be better than a tad over 20%, maybe 25%. This means either that the cost of getting these 40%+ efficiencies is so high it doesn't pay for the difference OR the innovation kills the reliability OR the conditions needed to get this efficiency are unrealistic in a real world like say < 1 degree offset from the perpendicular OR there's just a hell of a lot of work still to go. I think a detailed analysis of past failures to get to market could be very interesting.
Getting back to PV's, or any renewable energy the big clincher is always going to be storage, more storage and maybe more storage. With PV's the efficiency might be 44.7% but I'm sure that's for perpendicular light and so either a lot of panels at different angles or a direction adjusting system is going to be needed. Also based on my experience with our PV installation you need enough over capacity to get your required power on a heavily overcast day. We exceed our winter electricity usage from about 10:30 and drop below that level again after about 15:00 and in summer probably from 7:00 to 17:00 and inbetween that we produce 3x more than we need contributing to business peak use but not to residential peak use so I have to wonder how efficiently our spare kilowatts make it over to the business districts?? But if it's overcast we only get about 500W to 1kW out of what is a 4kW rated system, so 1/8th to a 1/4 during the peak light periods. This really does make the 15%-30% projections you mentioned sound realistic not including the zero input from PV's overnight.
Don't get my ramblings wrong, I still believe we need to go renewable, just that we need to do a lot of thinking about how it's going to work.
Finally, thanks Elizabeth for an interesting post, it's good see the world is plodding on despite a few setbacks.
From building and operating a small 2KW system (built 3 yrs ago) I can tell you from experience the tech still is not viable from a economic standpoint.
Sure you can build them and they work but the costs vs return are outrageous. I am not just talking the installation and purchase price but their are many cost often left out of the reports such as large maintence and upkeep cost these system do not maintain themselves and require preventive maintance as well as repairs and unlike a large generator or even a big turbine their power output is small so were a gas turbine could power 10,000 homes and a small force of 20 total employees maintain 5-7 of these (their is just this kind of plant 40 miles to the south of me with 18 employees and 5 generators) to supply that many homes you would need hundreds of acres of land and a very large workforce to maintain clean(yes for opt eff cells need cleaned they are glass by the way), PM'ed, protected yes a large solar field requires security guards to protect their assets, repair.....etc. These cost only increase as time goes on. And unlike the turbine that works day and night through rain and snow the solar field only produces solid power from a few hours after dawn to a couple hours before dusk on days were the sun shining solidly on cloudy rainy snowy days you end up with 20-40% power.
Solar is a great tool but is by no means the solution at least not for a long time it needs so many additional puzzles peices before it will truely be viable from an ecomonics standard. This is not to say the heavy hand of Goverment can not force it but that only hurts all the people as it can only result in large cost increases for power.
Thanks for your real-world perspective, LetoAtreidesll. It's always good to hear fromour reader experts who have this type of experience to provide context for some of the new technologies being introduced and researched.
I have installed on my roof a 4200 W solar system. It's been in operation for about three years now. It's installed cost (grid tie - no batteries) was ~$30K.
On a really good day the system produces ~24KWhrs. My home uses on average about 24 KWhrs a day. Significantly more if one turns on the AC (sometimes required during the summer). Average daily production over a year runs around 13 KWhrs.
Snow on the panels cuts output dramaticly. I go out with a roof rake to try and clean them off. About a 1/2" of snow cuts output to nearly zero (39 Watts typical).
Cold weather makes the panels more efficient, but the big seasonal effect is just plain fewer hours of daylight. (I live in New England).
The panels I use are rated at 14.6% efficiency under "Standard Conditions". For a signifincantly higher cost you can get commercially available panels with claimed efficinecy of 21% (SunPower). The solar cells claiming efficinecies of 30-40% are concentrated cells (ie needing a optical concentrator lens). These cells only work in very high brightness sun conditions since there efficiency requires a high operating temperature. There manufacturers recommend them for high sun areas like the Southwest. Obviously they are very expensive, since they require optical lens assemblies.
For reference, "Standard Conditions" refers to 1000W/square meter illumination with surface perpendicular to solar input. I don't remember the temperature off hand but it's something like 25 degrees C.
I just thought I would present some hard data to this dicussion.
When the system was installed, Mssachusetts had a generous Solar Renewable Engergy credit (SREC). For every Megawatt-hour the system produced an SREC was issued. These credits were to be purchased by the power generation companies to compiy with renewable energy sourcing targets. This was supposed to create a demand for independtly generated SRECs. It worked for the first year and for each credit I recieved ~$500. I think I had 3 credits that were purchased at this price. Unfortunately, far more people/companies also saw this as a good thing and built quite a lot of solar capacity in the following year. This produced an oversupply of SRECs and the price was significantly depressed (~$235/SREC). Massachusetts is no longer allowing new installations under this system in order to stabilize SREC pricing.
The original calculations for payback showed something like 6 years for ROI. The SREC pricing has significantly disrupted this. I have a low interest loan on the installation (2.75%) and use the not isignificant electric bill savings to pay it down, along with the SREC sales proceeds.
I have continued to watch the prices of solar panels and other equipment and have seen them decline significantly. A system like mine could be built now for at less than half of what I paid for it.
I've learned a lot about how it should have been done, to make operational issues easier, but I have no regrets.
Good Post. As the design and manufacturing processes improve, costs will go down. This is exactly why the government should be putting its money where its mouth is. In other words, the governments should be buying solar for government buildings, miltary bases, etc.
It was not right to just "loan" Solyndra $500M, but it is right to buy $500M of solar panels. It will help develop the industry to spend $500M on solar product (better be made in America) than it would be to buy aircraft and tanks that many times those folks don't even want.
The point is to buy different technologies and see which ones work best.
Finally, in addition to improving this industry, there is payback in lower electric bills across the board.
"As the design and manufacturing processes improve, costs will go down. This is exactly why the government should be putting its money where its mouth is. In other words, the governments should be buying solar for government buildings, miltary bases, etc. "
Al Klu, cost will comes downs only when technology becomes popular and competition happens with in the manufacturer.
The chicken and egg thing again. You and I are saying the exact same thing, except I am proposing that the government help make the technology popular. You are waiting for "someone else" to make it popular first.
If the government is procuring solar panels, and putting them on roofs of local government buildings (schools, town halls, courthouses, military complexes), the image of solar panels in use becomes widespread and therefore more popular. As the general public sees this technology as common, and hopefully effective, they are more likely to participate by buying into solar.
If you see solar panels everywhere, wouldn't you be more likely to buy some for your own home? As more people buy solar, there is more money going into the businesses, inlcuding manufacturers, and there will be more competition.
A precedent for this process is the entire space program, especially in the 60's. How many new products and product improvements came from the government sponsored space program? My company was one of the very first companies to develop the electron beam welding process for industry. And this was because the government purchased space equipment that needed the EB weld technology.
"You and I are saying the exact same thing, except I am proposing that the government help make the technology popular. You are waiting for "someone else" to make it popular first. "
Al Klu, would you think government will invest for it, I won't think because it requires huge investment. I feel the best way is government or local states can offer subsidies for citizens, who are opting for outright purchase of solar PV cells and other components.
I would love to put solar panels on my roof here in Connecticut. We have a perfect, unobstructed, south facing roof. However, even with all the government subsidies, our payback is targeted for about 15 years (optomistic sales pitch, the reality is that it would be much longer). After this time, I would expect the equipment to start needing repairs, or even replacement, which basically says that we are not saving anything. A big hidden expense will show up when we need to re-shingle our roof (about 5 to 10 years from now). They would have to come out, take off the panels and supports, then put them back on after the roof is shingled. This quoted cost is about $2000 dollars - wiping out any savings from the panels.
There are a few companies that are popping up that will put the panels on for "free", but basically, we would be paying near normal rates (no savings), for them to make money on our roof. And we would still need to pay the $2000 for the re-shingling of our roof.
I would take the plunge if the payback was 5 years or less. That would need a few more incremental steps in cost reductions. I don't know why you think individuals in Middle Class America have more money for this huge investment than our government. I certainly can't "opt" to purchase PV outright at the present time.
And you are asking the Government to just "give away" money (that's what subsidies, grants, and tax rebates are really doing) with no return on investment. My way, at least the government power bill will be reduced - hopefully by the amount of the investment.
Thanks for your comment, Al Klu. Actually the government is doing research and investing in solar and other alternative energies, and I agree that you're right they should be taking the initiative here.
Here's a story you might be interested in reading about how the Army is investing in solar: http://www.designnews.com/author.asp?section_id=1386&doc_id=271748
"Thanks for your comment, Al Klu. Actually the government is doing research and investing in solar and other alternative energies, and I agree that you're right they should be taking the initiative here."
Elizabeth, in most of the countries there are energy crisis and governments are always looking for alternate source of energy. Solar and wind are not always dependable because they are seasonal in most of the countries. In some countries they had developed hybrid systems, a combination of wind, solar, rain etc; so that energy can be produced throughout the year depends up on the available energy sources.
Good points, Mydesign, and actually today I am writing a blog post about how the U.S. Navy wants to build a space satellite with solar panels to beam solar energy from space, solving the availability/dependability problem. So stay tuned for that! Clever stuff.
"actually today I am writing a blog post about how the U.S. Navy wants to build a space satellite with solar panels to beam solar energy from space, solving the availability/dependability problem. So stay tuned for that! Clever stuff."
Elizabeth, most of the satellites are equipped with solar panels & energy storing device for powering transponders. During day light they convert sun light to solar energy and stores in batteries for night usage.
I wasn't aware of that, Mydesign, that's really interesting. So perhaps it's not so far off that they can use solar panels in space to beam electricity to earth. The Navy wants to convert the solar energy to radio waves and then beam it via antennas on satellite modules. I think it could work!
"So perhaps it's not so far off that they can use solar panels in space to beam electricity to earth. The Navy wants to convert the solar energy to radio waves and then beam it via antennas on satellite modules. I think it could work!"
Elizabeth, am not sure about transmitting electricity from space station to earth through atmosphere. Lots of hurdles are associated with this type of conversion and transmission. It won't be economical too.
Hi, Mydesign, well, yes it seems very complicated, but a Navy engineer is working on it and he has already built a prototype for this type of thing. Here's the article I wrote: http://www.designnews.com/author.asp?section_id=1386&doc_id=272395
I would be really interested to know what you think.
Yes, of course, this is in the early stages, Mydesign. You might want to check out the message boards on this story--there is a lively debate going on! I am sure you would have something interesting to add.
The truth is we could make the efficiency up 2 to 10 times greater by simple reflectors concentrating the sun's energy from a larger area onto a few solar panels . But, the installers and salesmen aren't smart enough . And the labor to install panels is three times the cost of the panels . I can design panels which output twice to four times the energy but cost half as much with todays materials. But, the guloble public in their ignorance, pay thru the nose for mediocre equipment.
That's interesting, Dennis. Are you sure there isn't a company working on this? Do you work in the solar cell industry? If it's such an obvious solution, I am surprised no one is doing this. I've written a lot about solar panels and efficiency but haven't come across anything like this yet.
Elizabeth M. My scheme isn't so much raising the specific efficiency as in putting more sunshine on the active area so more electricity is produced. I use flat mirrors both above and below the array of solar cells reflecting more light onto them. That gives much more electric power per dollar of cost. The several solar companies representatives I have spoken to said they were selling OK for the prices they charge and besides the manufacturers won't warranty concentrated light on their panels because they might get hot from the extra sunshine and damage the panels. I said collect the heat and use it for direct thermal purposes. They said they were not in the heat business only electric power. Aparently no one is going for a better higher powered system at lower cost.
I am a multiple industry expert (A "Generalist") in many diverse technologies. I combine ideas from diverse fields to create better solutions than a specialist can...
Al Klu, two year back I had installed PV and solar energy generating system over my roof and I got 60 % subsidy from local government. Moreover, they have the buyback policy for the excess generated energy to grid.
I appreciate your input. Can you give me some specifics?
What state are you in? How big a system did you put on? How much did it cost? How much of your subsidy was federal and how much was from the state?
How effective is your system? What was your electric bill before and after installation? If you don't want to share that, what is your average usage in Kwh before and after installation? (i.e. how much electricity have you produced?).
This will tell us your payback.
How about maintenance? Do you have to go up on the roof and wash off the panels? Do you have snow? Have you thought about what's going to happen when you have to reshingle your roof?
Al Klu, first am a non US citizen, I mean am residing in one of the Asian countries. For 3 KVA systems, all together the total cost is approximately $6000 and in that I got a subsidy of 60% (30% from State and another 30% from Federal government). As of now my total electricity bill comes to ¼ of the previous bills and I have the option to sell my extra power to grid. I hadn't connected AC and Pump motor to this system and hence paying these charges to the power supplying company.
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