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Solar Panel Breaks "Third of a Sun" Efficiency Barrier
Zothecula writes "Embattled photovoltaic solar power manufacturer Amonix announced on Tuesday that it has broken the solar module efficiency record, becoming the first manufacturer to convert more than a third of incoming light energy into electricity – a goal once branded 'one third of a sun' in a Department of Energy initiative. The Amonix module clocked an efficiency rating of 33.5 percent."
According to wiki this happened in July. Also, for info, they have received over 180 million dollars in grants from the government, and closed their las vegas plant in order to "focus on international opportunities".
From the article: "The solar module efficiency is the efficiency of the panel, and not the same as the efficiency of individual solar cells from which it's comprised. At the moment, solar cell efficiency can just exceed 43 percent for concentrated systems. It's the module efficiency, however, which reflects the amount of electricity a PV system can produce."
If you include external costs, it's a lot closer than you think.
You are welcome on my lawn.
That's just about where the miracles stop reliably. You may or may not find some special cases in which those actually make sense (given that we're talking about concentrated solar and 2-axis drives are mandatory, those cases become even more special), but at large scale it's just not worth it - even without considering the need to store the energy, so you have it when you need it.
Every 6 months on Slashdot we read about higher efficiency solar panels. Virtually none of them are available on the market, and if they are, they're only available to large-scale commercial installations. Right now, the best you can do retail is about 20%; some panels are barely 10%.
A condition for any prize should be "available in half-dozen quantities to individual purchasers."
The best return on investment remains solar hot water - we're talking an order of magnitude in efficiency per area between common solar panels and evacuated-tube hot water collectors. We waste enormous amounts of energy heating hot water and heating homes...
We'd also save billions of dollars if we stopped selling clothes dryers that are hideously inefficiency; elsewhere in the world condensing dryers are the norm and in some cases dry clothes faster.
Please help metamoderate.
Unfortunately, this is a concentrated light solution. This means that the figures quoted for efficiency are in the presence of direct sunlight. However, this is only a proportion of energy generated from PV modules, hence the "efficacy" and therefore, total energy production, of concentrated solar solutions is less good than unconcentrated modules.
The reason comes from diffuse sunlight - light that has been diffused by the atmosphere or by clouds. This typically accounts for 10% of module illumination in direct sunlight, and much higher in the presence of atmospheric haze/cloud; even in lightly overcast conditions, you can expect unconcentrated PV to yield approx 10-15% of direct illumination yield because of the diffuse illuminance.
Diffuse light cannot be concentrated by optics, thus concentrated solar PV modules cannot utilise the diffuse light (more precisely, they can utilise it, but not concentrate it - thus if the system uses a 10:1 concentration, then the energy yield from diffuse illumination falls from 10-15% to 1-1.5%).
A boost from 30 to 33% efficiency by switching to concentrating modules could be completely wiped out by the loss of diffuse yield, even in direct sunlight. In non-direct sunlight, hazy or cloudy conditions, the yield can be reduced much more severely; resulting in a net reduction in productivity, despite the higher nameplate efficiency.
This technology is most suited to areas with the most intense direct illumination; e.g. dry areas, at low latitudes (where the role of diffuse light is diminished in proportion).
It was new, purpose built, so had some obvious advantages, but what I took away from it was:
Obviously location and climate matter, but at the end of the day it was a viable and practical option, and one that made economic sense as well.
Sooner or later some bright government will figure out that by heavily subsidizing the installation of solar in homes they'll a) Develop a very viable industry b) drop solar costs due to volume c) get relected because everyone's electric bills will drop d) boost the economy because the money that was going to the electric company can be spent elsewhere. Now, I'm still a fan of hydroelectricity - if you need to generate electrical without generating CO2 and pollution, and without the no-nukes crowd at your door, there isn't a better way to go.
Three Squirrels
For almost any new building it is worth covering the roof with solar PV. It might take 10-15 years to recover the cost, but then it is all profit. The savings are even bigger if you combine PV with solar heating. Installation is cheaper at the time of construction and the cost is a small fraction of the roof budget, let alone the cost of the whole building. If you are taking a mortgage then the cash from feed-in tariffs will more than cover the extra cost of the panels on your monthly payment.
Note: Based in building in the UK, further south it makes even more sense.
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SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
It looks like I can buy solar modules for a minimum cost of $1/Watt.
Assume an energy cost of $0.1/kWh. Assume an average of 12 hours of sunlight per day and a 50% of maximum average intensity.
$0.1/kWh * 1 year / 12 * 50% * 12 hours/24 hours = $0.01826
The monthly value that a solar cell generates is $0.01826/watt month.
Assume a yearly interest rate of 5% (monthly is 0.4074%)
Since the cost of a solar cell is $1/watt, work out the number of months that a 1W solar cell must run for to generate $1.
PV = A/i (1-1/(1+i)^n)
PV = $1, A = $0.01826, i = 0.004074
n = 62 months = 5.17 years
The warranty on the reference cell is 10 years product workmanship, 25 years linear power.
So the value of the cell over its 25-year life span is $3.15/watt, with a cost of $1/watt.
This all neglects installation and grid-tie costs, but 50% average illumination per daylight-hour is conservative in most areas. Solar cells ARE worthwhile TODAY and WITHOUT government subsidies.
Efficiencies in solar cells are irrelevant. The only thing that matters is the $/Watt.
Reference Solar Cell: http://www.affordable-solar.com/store/solar-panels/CSI-CS6P-245P-245W-Solar-Panel-STD-Frame
I'd say it is 80% certain that he does not, with 2 sigma confidence
I am concerned about the long term effects of taking all that power from the Sun. How long before it starts to shine less, or doesn't keep us in orbit anymore. The whole idea of endangering the longevity of the Sun gives me shivers. Think of our children!
typically 30 years with 80-90% of the original efficiency, less if you live in a hurricane / tornado prone region.
If anyone reads the article carefully...
They state in the article that individual cells can already reach 43% efficiency - which matches the top end of that chart.
The overall efficiency of the PANEL (made up of many cells) is lower though. This 33% is the record for the efficiency of the PANEL as a whole, not for the individual cells.
Concentrated cells tend to wear out much more quickly. They get much hotter, and junction heat is what determines the life of any semiconductor.
http://ths.gardenweb.com/faq/lists/laundry/2004120958010854.html
"All else being equal (i.e. not including household heating/cooling issues), condenser dryers are slightly less efficient than their vented counterparts, typically on the order of ~15%. The real design intent of condenser dryers isn't improved efficiency, but the simple fact that they don't require a vent duct, permitting easy installation most anywhere (ideal for apartment dwellers, etc). "
A gas dryer is going to be much more energy efficient than an electric dryer considering that ALL the heat generated from the flame enters the tumbler. Typical power plants can only transmit up to ~40%% of the heat from their power source to the dryer heater coils.
Min energy eff electric: 3.01 lb/kWh
Min energy eff gas: 2.67 lb/kWh
Electric is 12% more efficient at point of use
Total heat efficiency including power generation:
3.01 * 40% = 1.2
2.67 * 100% = 2.67
most efficient setup would be an external venting gas dryer in a unheated space like a basement or garage since you would not be adding load to an HVAC system.
Solar cells and silicone sealant share the same property: we have no idea how long they're good for.
Originally silicone cement had a 3 year warranty. Then none failed and they made it 10. Now it's 30. I have aquariums that are forty years old that have just a microscopically thin lawyer of silicone holding hundreds of gallons of water in a glass box. We have no idea how long the stuff will last, it could be a hundred years or more for all we know.
Solar panels started being deployed in the 70s. They all still work and were expected to give 10 years service. To be sure, efficiency diminishes over time, but that's a secondary consideration to the fact newer panels are much more efficient. Somebody can use those old panels though.
Need Mercedes parts ?
Why not cite NREL's official and current chart? http://www.nrel.gov/ncpv/images/efficiency_chart.jpg
While they may have hit a new record for overall efficiency, any sort of concentrator photovoltaics require sun tracking, significantly increasing initial system and maintenance costs.
This is true. They've used too much solar power and now in some parts of northern scandinavia there is darkness for 3 months of the year.
Why guesstimate solar production? Use NREL's PVWatts application: http://gisatnrel.nrel.gov/PVWatts_Viewer/index.html
Click on your city. Click 'send to pvwatts'. Enter the solar system size in kW (default is 4.0). Click calculate.
Depends a great deal of where you live, of course, because energy prices and solar radiation vary quite a bit across the USA.
Christ, I love it when people with zero actual experience with things dump on those things just because it makes them feel good.
Materials price:
Been dropping FAST for about three years.
Install cost:
What? You mean the cost of paying an installer? Or the cost of DIY? Neither is high.
Batteries suck:
"Batteries never die, they're always murdered". Mine are 22 years old and test the same as when new. Why? Because I don't try to fuck them like a big pile of lead-acid bitches.
Motivation:
WTF? Either you want to, or you have to, or you don't. I had to. And I wanted to. You? Guess not.
Home built panels:
Almost "why bother?", considering how inexpensive the commercial models have become.
Hail:
Are you fucking kidding me? Seriously? You do know regular commercial brands are warranted up to golf-ball sized hail? In one insurance claim, an entire RV was written-off due to tornado hail damage. The only thing salvageable? The PV array. It was undamaged.
Listen, there's a whole World of shit I know nothing about. So, what I don't so is talk about that shit as if I'm a fucking expert on the subject. Because I'll just look like a cunt if I do. Give it a try.