Makes me proud to be a free market republican treehugger.

Looking at pictures of these items, does it look like they allow light through so that two or more layers can be stacked on top of each other?

silcon and silicone are two quite different things ... and I for one haven't heard of silicone solar cells ... and then, while you are correcting the article: silicon makes up roughly a quarter of the earth crust - so its not exactly "limited" in the usual sense of the word (however the processing capabilities for turning it into solar grade silicon may well by)

One thing not mentioned is that PV panels are only part of a PV system. That $3-4/W quoted for "solar power" only includes the PV panels. Throw in inverters, hardware, and installation and you're talking $8-10/W. As a result, if the costs of the inverters, hardware, and installation don't drop it doesn't matter how cheap the panels get -- they could be free and PV would still be uncompetitive with fossil fuels.

My point is that PV cannot "clobber" fossil fuels based on development of the PV panels alone. This is significant because a number of companies are promising super low-cost modules in relatively short time frames and claiming they will meet the magical $1/W milestone required for cost-effective PV. What they neglect is that this milestone depends on other components of the PV system reaching cost milestones of their own, and accelerating the timetable on a single component -- in this case, the PV modules -- will not do much to accelerate the timetable for PV systems as a whole.

In short, if they claim they will "clobber" fossil fuels on an accelerated time schedule on the basis of PV module cost alone, their goals are critically dependent upon other companies doing half the work for them. That's not to say that pursuing low cost on an accelerated timetable is a bad thing; rather, it is to say that even if we have modules at $0.80/W in five years, PV will not necessarily be clobbering fossil fuels. And modules for $0.50/W will most certainly not undercut coal and nuclear by 50%, though that might be the case if the entire PV system costs $0.50/W.

I have much more faith in manufacturers who are looking at the entire PV system, even if they do not themselves manufacture or install the other components. Crystalline silicon manufacturers are much more mature than their thin-film counterparts in this regard, and I don't think thin-film companies will be as competitive as they can be until they collectively learn this lesson no matter how low their module costs are. Some of them do -- First Solar comes to mind -- but it appears that Flisom does not.

And on another note, it drives me nuts when writers authoring a science and technology column don't know the difference between silicon and silicone....

While it certainly warms my heart to hear solar will "clobber" fossil fuels within ten years, I somehow doubt the timetable will be met, probably for some of the reasons listed by Alan.

Hopefully a combination of carbon taxes to the fossil fuel industry, or increasing emission standards, which lower their returns, or the depletion of shallow, high-purity deposits will drive the cost of fossil fuel power up to meet solar at some price which is reachable sooner, rather than later.

Alan -

Help me here. I'd like to exclude installation costs, as I like to do everything myself (call me cheap - haha). I'm also excluding batteries. Costs as I see them today:

- Mounting hardware would cost in the $0.30 per watt range
- Inverter (Sunnyboy 6000W @ $3850 per mrsolar.com) is $0.64 per watt

Assumptions:
- 6000W system
- Cost $2.10 per watt (PV panel at $1/watt, hardware and inverter as stated above, plus 8.25% local sales tax)
- 75% efficiency - (4500W/h of generation capacity)
- 4.7 hours per day average of sun
- 20 year lifespan

Using those assumptions, a 6KW/H system would cost $9450 and generate 634 KwH/month (4.7 hours/day x 6Kw x .75 efficiency x 30 days/mo). Lifetime cost per KwH is 6.2 cents per KwH.

Obviously, this is a simplified cost model - but if we really got those prices for PV panels - that's WAY cheaper (residential) than I'm currently paying (12.9 cents per KwH).

Is my math off? I've never installed a system, but that's because they aren't cost effective today (at today's best price on Mr Solar.com's site of $4.6/KwH - total cost jumps to $24K (20 year overall cost of 15.8 cents/KwH). Keep in mind that this math doesn't take into account the time value of money - which I exclude, as I also exclude energy price appreciation - I make the assumption the two will roughly equal each other.

Bottom line - I think for a resident, $1/watt panel pricing could certainly make the technology economically feasible. Would it trounce coal/nuclear/oil? No, but it WOULD be cheaper. Slightly cheaper + better for the environment = mass consumer acceptance.

Now, just to address the issues of requiring banks and banks of batteries. People are not going to dedicate space to batteries en mass. Some other method must be devised that has higher power density (fuel cell/electrolyzer? - not a clue, just stating this issue needs to be addressed also).

Indeed, it bugs me also when authors who should know better confuse silicon with silicone. Let's just say that silicon would make a very lousy breast implant.

I have a question for those of you who are in the know:

I see a bunch of prices quoted as being dollars per watt. I know that a watt is a rate of energy flow (consumption or production, depending on what you're talking about), and a watt-hour is a unit of energy. When they say that the tipping point is $1 per watt, do they mean price per power generation capacity? This is what I suspect, but I just wanted it verified.

Anonymous:

Non-module costs for PV systems currently run about $4/W, so if you take out the inverter and installation costs (which can run as high as $2/W, though I think $1.50/W is more typical) you're still left with something in the neighborhood of $1.50/W. That's a typical, benchmark value of course, so your mileage may vary, and if you're going to do the design and installation yourself you can also deduct engineering fees and the like from that. But in addition to hardware, which I'm skeptical you could get for anywhere near $0.30/W, you have to pay for permits, inspections, and grid connection. And if you're unfamiliar with the NEC electrical codes, installing yourself could end up being more expensive in the end than just hiring a professional from the get-go. (It also implicitly assumes that your time has no value.)

As for your cost calculation, a proper financial analysis needs to account not just for the time value of money, but interest paid on loans used to finance the system and a suitable discount rate (essentially an opportunity cost, though it has very little effect on the analysis). And assuming that increases in utility rates will cancel out the time value of money is dubious, particularly if you pay cash up front for the system (thereby spending all of your money when its value is highest). That said, 6.2 cents/kWh is not that far off for a system costing $2.10/W installed. But in my opinion, without improvements in the non-module costs, that price is unrealistically low even if the modules become free and you do the installation yourself.

I'm in complete agreement with you on batteries -- without some efficient storage medium, PV will be limited to peak power applications. It can still provide a very significant fraction of our electricity needs without storage, but it will never be suitable for baseload. And in that sense, it is inappropriate to compare the costs of PV to those of coal or nuclear. Residential users will always compare its cost to retail electricity prices, but without storage utilities will compare its generation costs to natural gas turbines, hydro, and the like.

Berkana:

Yes, $1/W means the PV system costs one dollar for each watt it is rated to produce. The "rated" power is essentially the amount of power it will produce on a cloudless day with the sun high in the sky, so it's often referred to as "peak" power. If you look hard enough, you'll find cost per watt figures for all types of power plants, not just PV. It can be a misleading number, though, since a coal plant can run at peak power 24/7 while a PV plant usually produces substantially less than its rated peak. As a result, PV plants must be must cost much less per peak watt than a conventional power plant in order to be economically competitive with one.

Lots of big numbers out there for sure. I decided to give a small 45 watt non poly crystaline set (no pretty blue crystals) of three panels a try. Harbor Frieght had them for 200 bucks including a strange, complex multipurpose controller with all the mounting hardware.

Fun experiment and no way did this system ever get the 'big Numbers' advertised. Nice unit to charge a few little batteries but nowhere near enough to sustain even the trickle charge to my four Deep cycles that run my inverter system. I live in New Mexico so we do have pretty good sunshine to work with.

I could spend 1000 dollars and probably get enough to maintain the batteries during a storage period. Solar has a ways to go for sure. Don't give up, keep experimenting and find the true power of the sun,

Sandia Laboratory in Albuquerque NM has tried it all.
A very tall tower surrounded by a massive mirror system can cook sodium with an impressive bright white glow seen for miles while I drive south on Juan Tabo it is interesting to see it cook.

A home completely designed with off grid capabiity, auto sun trackers, storage tank and all, was raffled off by UNM in Albuquerque several years ago, within 3 years all of the high tech exotic equipment was removed and the house is now back to the grid. "Nice try but no cigar" It's not for 'sissies' with low budgets. http://daflikkers.blogspot.com/

It is only a dollar a watt while the sun shines. Assuming that you average 8 hours a day 365 days a year (maybe in West Australia where I live but not in many places) the cost is really $3/watt as you have to install 3 times as much as a coal station which can run 24 hours a day. Many people miss the point that you have to pay to install enough generation to cope with the peak, even if it only occurs 10 minutes a day (or live with power cuts/restricted power thru smart meters).

what is the incredible difference between the 6000W inverter for $3850 made specifically for solar and the $299 6000W inverter used for a truck to power tools on a job site?

http://www.sportsmansguide.com/cb/cb.asp?a=320653

For $3850, it's made to run non-stop at full capacity and syncronizes the sine wave with the grid. If you tried to connect the $299 unit to your home, all kinds of pretty sparks would fly. :)

Alan - this is "anonymous"... I forgot to put my info in. I'm very happy to see someone discussing the FULL price of installing solar. Do you have more info on that non-panel cost of $4/watt? Is there an article somewhere that discusses this technology's costs A to Z, so I could see the full range of costs? I've always felt it was NOT cost effective yet, but you make it even more so. Thanks.

Brian

Solar can't replace traditional power generation without a viable means to store power for when the sun isn't shining. What can it do right now and in the near future:

- Cut peak loads on the utilities when "everyone" is using AC. Currently many utilities use "peaker plants" to meet this demand thus burning that much more fuel.

- Reduce strain on the grid during peak demand times With solar on the roof you have power generated close where it's used and thus reducing that strain. Add enough solar roofs...

If the costs can be brought down like the article says the next big challange will be storing the power.

Hi,
Is it me or does it look like there might be enough light passing through thin films to allow them to be stacked?

vk

G. Smith:

When folks say "X dollars per watt" what they really mean is "X dollars per peak watt". This is true whether they're talking about PV, coal, nuclear, natural gas, wind, or whatever. Each of these types of plants operates at or near peak generation under different conditions are for different amounts of time. For this reason, different types of plants cannot be meaningfully compared using this metric. Think about it like this: The capital cost of a coal-fired power plant is somewhere around $2/W, but it has a very significant ongoing cost in that it must continuously spend additonal money on fuel. The cost of a PV plant, on the other hand, is all capital -- ongoing costs are quite small. So which do you suppose is cheaper, coal at $2/W or PV at $2/W? It's a meaningless comparison.

As for needing the generation capacity to meet your peak load, that isn't necessarily true. Your inverter must be sized to meet your peak load, but your PV panels do not unless they're your only source of power. It's entirely feasible for, say, a 3 kW PV system to meet all of the energy needs of a home whose peak load is, say, 6 kW, provided the home has stored energy available (generally the grid, in a grid-connected case, or batteries, in an off-grid case) and a 6 kW inverter. The size of the PV array is based solely on the amount of energy the home consumes.

toff:

As Brian says, if you connect that cheap inverter to the grid, you're going to have problems. The circuitry required to synchronize to the grid and disconnect from it when your PV system could pose a danger to line workers is expensive. I also suspect the cheapie doesn't give you a true sine wave, which can cause problems with your appliances if you don't select them carefully. It might be suitable for an off-grid system, but if you're going to store power in batteries you'll still need a charge controller (which can be found built into inverters, but it will bump the price up a bit). Inverters for off-grid PV use are more expensive than the one you point out, and those for grid-connected PV use are more expensive still.

Brian:

Unfortunately, the kind of data you are seeking is difficult to come by, at least in any sort of a detailed sense, and much of what's available is for special, one-off projects as opposed to standard, run-of-the-mill residential PV systems. That's partly because the entities who have the data are private and don't like to release it, but it's also partly because there are so many site-to-site variables, different mounting schemes, etc., that collecting it in a detailed, yet systematic way is tricky. I'm told the Department of Energy is working on a more detailed assessment of these costs, which would then certainly be published, but in the meantime you'll have to settle for backing the information out from other data, so to speak.

You can download a database from a project with the rather unweildy name of IEA PVPS Task 2 that provides information on several hundred PV installations around the world, some of which have cost information broken down into module, inverter, and other. The California Energy Commision also makes available databases of all of the installed PV system costs for systems making claims under California's subsidy programs. These only give the installed system cost, but based on knowledge of module and inverter costs it's pretty easy to see what's left over. Finally, the Department of Energy has done some benchmarking and published the results in various places. The benchmarks are "average" or "typical" values, and some installers will break the costs down a bit differently (though they generally get a similar total). The benchmarks have appeared in their Photovoltaic Program Plan documents, and their latest benchmarks have appeared in various documents related to the Solar America Initiative. Sorry for the lack of specifics, but if you Google on those titles or check the NREL web site you should find what I'm talking about without too much trouble.

There are some great comments on here!

Regarding the cost of PVs and this magical $1/W barrier, don't forget to take the economy of scale into consideration. Right now, the limiting factor in the cost of PV solutions are the solar panels themselves. The remaining technology already exists and is relatively simple in comparison. Once the solar panel component becomes economically viable, there will be a much greater demand for the power inversion/storage technology required to use it and the price for these components will deminish.

Tim -

I think thats what Alan and I are saying. Without an efficient storage method, it will only be good for offloading peak loads. We shouldn't discount this benefit - it keeps massive amounts of money from being invested into "part time" power plants running on gas or coal. Keeping these costs out of the supply chain helps tremendously. If everyone added solar panels to their roof with just enough capacity to generate 10-20% of their monthly load, we would dramatically alter the energy company peak loads.

I work in networking - and we have to design networks to support peak demand. If there were a way to "smooth" the curve, we could save tremendous amounts of money. This is the same concept that could save tons of money in the power grid. If the electrical companies could store their power efficiently - less plants would be needed.

Thin film will certainly be able to affect one piece of the puzzle - cost of the PV panel. I believe with that will come higher demand for installation services, better "packaging" of solar systems and higher volume production lines for inverters - all things that will lower the price of the "other" costs associated with solar power. These things will all make solar more affordable - which will definitely knock down peak demand on the grid.

If we can address the storage issue, we'd all be in a better place and could make the decision to unplug from the grid if we wanted. I know if that were an option for me, I'd certainly entertain the concept. I'm a big fan of investing capital instead of operating expenses. I hate OPEX. :)

Brian -

I got rushed eariler so I didn't complete all of what I was going to say but you covered it.

Be good to see some ideas for short term electrical storage. I have seen on TH and other places compressed air, batteries, producing H2, pumping water up hill, flywheels. Etc.

Not being in electrical distribution I have a question if someone can tell me:

So I do know it is true that electricity heats the wires somewhat and that of course heat
increases resistance and that = power lost.
So my question when you have peak load demands I would assume then that it would increase the heating that much more and even more power is lost in transmission.

Power lines are run at high voltage to reduce power loss. High voltage means low amperage, which means cooler.

http://en.wikipedia.org/wiki/Electric_power_transmission#Losses

That says loses are about 7.2% in 1995. Doesn't seem too bad. I know there are experimental lines that are supercooled to prevent any lose. They just cost a lot. and require other infrastructure since they are nitrogen cooled.

With a smarter grid communicating with smarter appliances, PEHVs and other customers for intermittent energy, the issue of whether solar or wind are appropriate for base load may not be as much of a problem. Consider that you match a wide array of non-base energy producers with a wide array of energy users willing to agree to buy intermittent energy when it's produced or off-peak energy.

That would have the effect of dropping demand for base load and peak load by bunching more usage that isn't time specific (it shouldn't matter precisely when your dishwasher runs or when your PEHV is charged) into times when energy is highly available.

Smart usage could eliminate the need for storage and for redundant baseload generation.

Hi pv heads,

I think I heard a similar story of the same kind of panel being produced by a South African group in conjuntion with the German energy council of sorts. you hear so many stories. Is this one true? I don't believe the current number's for price per/watt is correct, which leads me to believe the rest of the article is misbased. Lots of people have been working on this alloy, copper, pv. Lets see some proof.

I think what everyone is missing here, is that there are intangibles associated with even the current price of a PV system. My household energy prices have NEVER declined; they have only gone up. Working on the assumption that we will always have access to public energy is not very smart either- just recently, several enforced brownouts were announced for certain parts of the country. So you're paying for more than a kW. You're paying for peace of mind.

Lots of great comments here on the viability of Solar power! Also lots of comments on the cost of Solar vs Fossil, etc... It seems to me this is a very difficult comparison at present in that most people are not taking inot consideration the "life" of the system wether it be Solar or a home furnace of some sort. Also, not taking into consideration the eventual decrease in capital costs for Solar as it becomes more popular and manufactured en mass. Another factor one needs to put into play are the decreased (eventual) costs of Grid power itself as more Solar/Renewables are coming online. No fuel costs means eventual reduction in the biggest overhead costs the utilities currently have. The argument can go back and forth on the minutia and the metrics, but one thing is crystal clear. The cost of coal/oil/gas will continue to rise as long as demand increases and supply decreases. Both virtual gurantees unless we all destroy ourselves in Nuclear war. Also very clear is the the cost of renewables will continue to decrease as technology and efficiencies improve and manufacturing increases. Also, a virtual guarantee.