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Bo, Wind and solar are not 100% efficient. Solar is about 20% efficient, and I am not sure about wind efficiency.
In the case of wind and solar, the importance of efficiency is a little different than it is with fossil fuels. For one thing, with wind and solar, the energy source is free, so you are not wasting something that you paid for like coal, or oil, or natural gas. Also with wind and solar, no matter how inefficient it is, it does not create any pollution or CO2. So there is no environmental impact even it is inefficient. With fossil fuels, inefficiency means more pollution per unit energy produced.
Of course, efficiency is still important for wind and solar. The equipment is very expensive and you want to get the most bang for your buck.
John C. Briggs
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I wish solar was 1% efficent, because that would leave more room for improvement. Most panels are about 12% efficent, the ones at Sunpower are 22% efficent. With state of the art space panels approaching 40% at spectrolab.
What is important is $/watt and Watts per square foot. Solarbuzz list current price of PV at $4.80 a watt. You can multiply panel efficency by 93% to come up watts square foot. So pick a solid panel at 15 watts sqaure foot. The additional components needed are about $1.20 a watt. The big cost is hiring a contractor to install the system, and in my opinion a wasteful cost. I honestly think anyone could install a safe system in a couple hours on a shed.
Take a Tesla 200 whrs/mile say you drive 12,000 miles a year or 32.8 miles a day. You would need 6575 whrs. Thus at 15 watts per square foot and 4 sun hours a day, 110 square feet. The size is manageable. At $6/watt cost is about $10000.
So you are paying $10,000 to fuel a $100,000 car for 30 years. The sales tax will be 8.25% in California. Thus the cost to fuel is about the same as the car sales tax.
Furthermore, with remote net metering, you could pay someone say $12,000 to install pv in a remote location and net meter the energy produced. Remote net metering does not exist and virtually every group including politicans would oppose it because it costs them money and power.
So in response to John, I would say efficiency is not important. Space is somewhat important as you need 100 square feet of full sun. The costs would still be low compared to gasoline. The only thing is you are going to have to put up a big up front cost and worry about the panels on your roof and dealing with the utility.
Bill, I too think that people should be able to install their own solar panels, however, there are some things to keep in mind.
1) Penetrations are made through the roof that must be leak-proof and of sufficient quality that the wind-loads do not tear $26,000 worth of panels off the roof.
2) These are high voltage and high current DC systems (350VDC) as well as using 240VAC. So this can be pretty dangerous stuff. There are safety issues here.
3) In the state of Massachusetts, in order to get rebates, the system must be installed by a certifed professional. This tends to make self-install a non-starter.
Regarding efficiency, I tend to think about efficiency as being in the 17% to 22% range for most non-thin film panels. You can save a little money on the panels by going to thin-film, but if the efficiency is only 10% or less, you will double the costs of racking hardware, wiring, and installation, and it will take up twice as much room on your roof. These are serious expenses that must be considered.
Looking at SolarBuzz, they have the lowest price panels in different catagories$4.35/W Monocrystalline$4.17/W Multicrystalline$3.68/W Thin film
So you can save 50 or 60 cents per watt with the thin film, but the added cost of racking and installation will likely make this a more expensive installation. Additionally, you may run out of roof area before you reach the desired Wattage capacity of the system.
So I think in this way, efficiency can be important. At 1% effciency, the systems would be a non-starter. Even if the panels were free, the installed cost would likely be as high as a Monocrystalline installation due to high costs of racking and installing the system. Also, you would clearly run out of room to install them.
It definitely is doable to use solar power to power your transportation needs. I think this will keep a lid on the cost of other types of electricity. Once other forms of energy are more expensive than solar, solar will become very popular. At the moment, solar power is more expensive than standard electricity. The cost of Solar production is probably between $0.20 to $0.60/KWH. This far exceeds the $0.10/KWH for coal power.
There is a 20KW solar system being installed right outside my window as I speak.
LaterJohn C. Briggs
I would not dismiss thin-film PV for a couple of reasons- 1st, there are some companies that are working on making the installation of panels easier, more standard- and thereby cheaper. 2nd, the efficiency gap between thin film and 'thick' film (easier than spelling monopolygogetupgolp pv), is narrowing. And lastly, the real value of thin film is integrating it with other building material- i.e. when you get your house re-roofed, it may only cost a bit extra to use roofing material with thin-film PV integrated with that material- same applies for siding. See the nanosolar or heliovolt web sites for two leaders in this type of thin film- although nanosolar is actually ahead in that they are already manufacturing on a small scale. Of course, there are advances being made in polysaturgolu, er, regular PV production as well, especially in concentrated PV design, whether via focusing to a small area, or via the use of prisms or even dyes to focus different wave lengths of light.
Wait- Bo, Ryan- we're 'cool' if we listen to the EVCast? Sounds good to me, but could you explain this to my two teenage daughters? I'm afraid, according to them, I have never been cool. Ever. <sniff,sniff> :-(
Paul, As much as I love the idea of the price of solar power coming down with thin-film, I think this is many years away. Consider the following.
1) Early thin-film projects failed in the real world environment due to lack of protection and poor chemical stability. This will create an even higher burden of proof for the next generation of solar thin film to be accepted. Next time you are driving down the road, look at some of the road signs, particularly if there is any red printing. Sunlight is brutal on organic chemistries.
2) If new solar thin films come on the in the next year, would you put $10,000 worth of them on your home before they are proven? Consider that if they happen to fail, the failure will occur over time and you will not know for five or ten years if the product is any good.
3) Market forces will control the price you and I pay for the panels. If they can be produced at $1/watt (like we hear from every thin-film startup), we will still be paying $3.50/watt because that is the value to the customer. There is no reason for the manufacturer to pass the savings onto you the customer. Even with solar panels at $5/watt, there is a shortage of supply (at least for the moment), so prices are rising.
To me, thin-film solar panels are as over-hyped as many electric vehicles. Exaggerated claims and coming out in 2010.
When you use words like 20% efficient it leaves a tone like they are not efficient enough since 20% is low. 20% is actaully high, because it means the panels are producing electricity at 18 watts per square foot. Much more efficient than plants. This number is creeping higher an higher. At 20% efficenit panels if you install 1500 square feet of them you will have close to the amount of power for 100% of your energy use including transportation, heating, and electrical use.
Also, I saw one MPPT controller that the system is wired to 36V and the controller bumps it up to charge a 72V battery bank. Which is nice since there are many EVs using 72V systems.
Nanosolar already produces thin-film panels for $1 a watt. The only thing is they won't sell them to the public at that price. Thin-film are not over hyped they exist and many have long warranties. Solar is in a perpetual state of coming out in 2010, as there is always something new.
IMHO, this evcast show is partially reponsible for the lowering of gasoline prices. It might be a small show but it packs a punch, causing oil companies to shake in their boots. The value of this show is in the range of billions of dollars to consumers.
As for lack of articles seems strange the depletion came when oil prices started to drop. beep beep beep.
Bill, I agree, 20% efficient for PV is actually pretty good considering that fossil fuel plants are at about 30% efficient. Also, I don't find these numbers comparable. When a fossil fuel plant is inefficient, it creates unnecessary pollution. This is not true for solar panels.
Personally, the best thing for me about solar power is not being impacted by energy price increases. for the last 4 months, my electricity bill has been $0. So the $/KWH for electricity will not matter for me. I wish I could say the same about home heating oil and gasoline.
As for NanoSolar at $1/Watt, well, maybe this is true, maybe it is not. Nothing is out in the public except claims. As we know, claims can be exaggerated.
The numbers are not comparable. The only thing that really is important is $/mile. For gas cars they use mpg. For electric cars they seem to use whr/mile. Electricity depends on where you live and how the electricity is made in the area you are. However, a large percentage of the cost is fraud. Find hard to believe electricity is over twice as much in California as in Idaho.
Unfortuantely for electricity and gas prices they do not factor in wars, global warming, long-term supply risks, long-term demand, noise, pollution, risk of injury. The only thing you pay for is the bill. Unfortuantely all the above is etheir paid by the government or paid by the public. If gas had a fair tax on it, based upon any reasonable court, there would be a $5-$50 a gallon surcharge on it.
Hi John! I wouldn't say thin-film is over-hyped- it is certainly newer and more unproven- but we should see more data on how well they hold up as Nanosolar has been shipping panels to a utility in Germany- it will be interesting to see how they work there. As for what I would spend $10,000 on? Well- it depends. If thin film, including installation, were half the cost, and given any bit of a track record and/or testing by 3rd parties- then yes, I could go that route to take a small chance on a new technology. But, as we are several years from such an installation, I will get to wait and see how they perform more fully- lucky me;-) Or is it, Sadly, I have to wait:-(
Oops! New huricane coming into the Gulf of Mexico- even if it causes little damage, gas prices will go up some as many of the oil platforms shut down when these bad boys pass thru- and if it wreaks havoc at the refineries along the Gulf coast, prices will pop back up to what they were a few weeks ago in a heartbeat. Bad news for the short run, but hopefully good news for the long run, as it will remind people of just how precarious our fuel supply is.
Paul, Thank you for your thoughtful reply.
A few years ago, I lived in Utah. When I was touring the state, there was some kind of national park or project (I forget where now). In this park there was a hugh field of solar panels for almost as far as the eye could see. Very impressive.
Well it was impressive until I read a plaque in front of the display area. It said that the installation had failed after only a few years and had been shut down. The key problem seemed to be that the panels were not properly sealed and water got in and wrecked the panels. The panels were obviously fogged up and that alone would have been a problem for the panels.
So this gave be a great deal of respect for the important of high quality well tested technology for anything that will be exposed to the weather. So whatever technology we invest in, it is important to prove it out first.
So now back to magic ThinFilm panels at $1/watt. So maybe NanoSolar is shipping now, and several other people will be shipping soon. However, it will probably be another 5 years before the results are known. This gives well meaning people one more reason to wait rather than act now and get PV panels. This is not a good thing for the planet.
And, as I have already said, I don't think the end customer will ever see the $1/watt price. Markets do not work that way. Frankly, I hope I am wrong.
Bill, Hmmm, you seem to be unhappy about paying too much for electricity in California versus other parts of the country. Then you seem to want to greatly increase the price of gasoline. I wonder if you will be complaining about that next.
I am sure you realistic that one of the key reasons that California leads the nation in solar PV is they have a high cost of electricity. If the price of electricity was to go down, Solar PV would slow down, conservation would decrease, and pollution might increase.
As for gasoline taxes, I have mixed feelings. I am really a free market guy at heart. I think people should choose whatever car they like. Cars are a great joy from NmG's to Hummers.
On the other hand, we all have public things that we must share like the air, the roads, the security of the nation. I think people's free market choices in transportation and homes, etc, are damaging the public things that we all share, e.g. the air.
So there probably needs to be a balance here. The CAFE standards and the air quality standards have been the only tools the government has been able to develop yet. Gas-tax seems to be politically impossible both at a state and federal level. In fact, not too long ago we were seriously discussing a gas tax holiday. Can you image?
Additionally, I am not sure if additional gas tax is needed given the hugh run-up in gas prices recently.
Also, I think we need to be careful not to single out gasoline as the only problem. Coal, propane, natural gas, home heating oil, diesel, wood... they all create damage to publically shared resources such as the air.
But the future could be bright. I know a guy that runs his cars on electricity, heats and cools his home with electricity (geothermal) as well as using electricity for the normal things we all do. All of his electricity comes from Solar panels. To me, that is a beautiful vision of what the future could be.
I want gasoline to pay their fair share. You say you are free marketer, thus you should want a $10 gallon tax per gallon on gasoline. Go to any courtroom, and figure out what the damages gasoline and fossil fuels people thats about the number you would get. My lung capacity is about 80% than the average persons due to smog in the 1970s caused by fossil fuels. I have no complaints.
You could also say fossil fuels are 30% efficent and that plants to make the fossil fuels are 5% efficent. And the earth to convert those plants to fossil fuels as 50% efficent. Thus, PV being 20% efficient converting sun rays to electricity, vs. 1% for fossil fuels.
You may have a different idea of free market, but my idea is that suppliers and customers decide the price, not the courts.
You can use a timer to charge your Vectrix scooter. It is important that the amperage of the timer be sufficient for the task. I heard on the next show that it requires a cord rated for 20 AMPs. Many folks have their water heaters on timers and they are 30 or 50AMP units. Your local hardware store should have one handy for a reasonable price.