This Looks Very Good

We Phoenicians, who live in one of the best solar sites in the world, have been anxiously awaiting a solar electric technology that makes economic sense.    I have a couple thousand square feet of nice, flat room that is just begging to get be off the grid.  Already, solar is economic for individuals in Phoenix, but only if you are willing to soak American taxpayers and your neighbors for 85% of the costs.  It would be nice if it were, you know, actually economic and not just subsidy bait for tens of thousands of dollars.  I have dug into many analyses that claim that solar has a 5-7 year payback, but never seen one that achieved these returns without substantial subsidies and rebates (beware the term "energy payback" which is not the same thing as investment payback (pdf))

For a while I have said that I thought traditional silicon/germanium IC-like wafer processes for making solar cells was just never going to get there, and that some other technology was necessary.   This might be one such example:

JA Solar, one of the big players in the solar industry, is working with Innovalight to commercialize the latter's method for making silicon-ink-based, high-efficiency solar cells, the companies said this week.

... The solar cells are created by pouring an ink solution incorporated with silicon nanoparticles and then decanting the excess liquid to leave behind a crystalline silicon structure.

At the time of the 2007 announcement, Sunnyvale, Calif.-based Innovalight claimed its method not only resulted in solar cells that were cheaper to produce by as much as half, but that the crystalline structure resulting from the process made its cells more efficient at converting electricity.

Those claims now appear to be validated.

On Tuesday, Innovalight announced that an independent study of its method by the U.S. Department of Energy's National Renewable Energy Laboratory and the Fraunhofer Institute for Solar Energy Systems in Germany confirmed that its silicon ink-based cells "demonstrated a record 18 percent conversion of efficiency."

The 18% conversion efficiency is close to a record for thin films, but must be the "record" for production models, since higher conversions have been achieved in the lab.  18% is very good for a production device, particularly if it is cheaper to manufacture than current cells.


  1. LoneSnark:

    So, assuming this is all true, what does that make the time horizon for payoff with and without subsidy?

  2. Nancy:

    "We Phoenicians"

    Why did I suddenly think of an ancient seafaring civilization? :)

  3. Henry Bowman:

    Below is a letter written to the Albuqueruqe Journal in January of this year by a fellow who closely examined a PV system for his house (he lives a few miles north of Albuquerque, NM). His remarks stand for themselves:

    Thursday, January 15, 2009
    Free Solar Power Is Hoax

    By James P. O'Loughlin
    Placitas Engineer

    The article N.M. Solar Energy Plan Expanded, about the state Public Regulation Commission's promotion of grid-tied photovoltaic (PV) power generation states that homes and commercial establishments that invest in PV installations will have “free” electricity.

    I evaluated such an installation for our house using Public Service Company of New Mexico PV information on its Web site. I checked the results against more sophisticated resources and found the PNM results to be in good agreement.

    For my house, the required system has a DC rating of 4 kw to accommodate a match to our average energy consumption of 475 kw-h per month. The PNM Web site states that a PV system's cost is about $10,000 per kw, or for our case about $40,000.

    This is consistent with the numerous PV system components and integrated packages available, plus the installation, fees, periodic inspections, maintenance, taxes, insurance and other incidentals. Based on a 20-year life and 6 percent cost of money, this comes to a monthly cost of $286.57. The monthly cost for the same amount of energy from PNM service is $42.75 — where is the “free” electricity?

    There is an insurmountable fact of nature that forces photovoltaic to be several times more expensive than conventional power generation: The sun doesn't shine for 24 hours a day. This requires that a PV generation installation must have a power rating that is about six times higher than a continuously running convention installation for the same energy output.

    At this time, PV panels account for around 50 percent of a system's cost, or $5,000 per kilowatt. The other part of the PV system is based on mature technology, the cost of which cannot be reduced. The only way to reduce the PV power generation cost is to reduce the cost of the panels. Even if we take the most extreme, totally unrealistic case of reducing the PV panel cost to zero, the immutable factor of six in power rating still dominates and results in a cost of $143.29 for $42.75 worth of electricity.

    The cliché about investing in research and development to decrease the cost of panels and make PV power generation competitive is an unachievable myth that is fanatically pursued by the government and other groups having various and peculiar reasons.

    When reality is not acceptable, the government can fix it with political alchemy. Through the influence of pressure groups and lobbyists, state and federal governments decree that photovoltaic power generation must be implemented. To fix the inherently expensive PV power generation problem, governments provide tax credits, incentives and other forms of subsidy to cover up the excessive cost.

    This does not reduce the actual cost; it just transfers it to the general taxpayer or ratepayer.

    There are both state and federal incentives. PNM has a PRC approved plan that pays 13 cents a kilowatt-hour for grid tied PV power. Actually PNM doesn't pay it. It is charged to rates paid by their regular customers to help subsidize PV power. Even with this money shuffling, those who buy into PV power installations still pay considerably more for electricity and will never recoup their investment cost. The rest of us get stuck for the subsidized difference.

  4. Dr. T:

    If electricity generation from solar power becomes twice as efficient as today and half as expensive as today, it will still require a 40% subsidy at today's electricity prices.

    Electricity from solar power is less cost effective than powering vehicles with ethanol. Both are terrible ideas that would die without the government wasting our tax money on subsidies, tax credits, or mandates (such as diluting gasoline with ethanol).

  5. Roy:

    Per O'Loughlin's numbers (in the letter quoted just above by Henry Bowman), the long term expense ratio O'Loughlin saw between photovoltaic solar power and conventional was about 7 to 1. (Observe this ratio would change if, say, one had to pay for all the infrastructure to run power to one's cabin in the country.)

    O'Loughlin reported that the PV cells themselves made up half the installation cost. Hence, even if the PV cells were free, that would still make the PV to conventional ration 3 to 1. Hence (except for subsidy by political force), not a wise choice (and, as Coyote noted, certainly a choice frought with moral problems regarding wealth transfer). Would that letters like O'Loughlin's and comments like Coyote's showed up on more editorial pages.

    But does this calculation lead to PV never being a moral or wise choice? Such that we ought give up PV R&D? Nope. At least 4 variables may change such that the PV to conventional ratio changes. Conventional costs can increase (either by having more costly infrastructure or more costly fuel). On the other hand, PV total cost can decrease by means in addition to a lowering of cost of the PV cell. The installation industry could develop driving installation cost down. PV cell manufacture cost could decline (tho obviously not to zero). And, perhaps key, the performance of PV cells might improve.

    Thus consider this scenario: slight increase in conventional cost. PV system installation cost decreases slightly. PV cell manufacture cost cut to half. PV efficiency increases 3 or 4 fold.

    That's what intrigues me about Coyote's report of 18% conversion efficiency for a production rather than lab device. Does that approach the magic number for improvment? My own hazy recollection says that commercially available cells run about 6%, making that 18% the 3 fold increase that could make the difference.

  6. John Moore:

    I think Roy's analysis of cases where PV would really make economic sense is unlikely. The simple fact that solar energy has a low areal density limits how low the power collecting system costs can go. Also, since the qualify of the power is poor (it is DC, varies dramatically with sunlight, and shading just one panel can significantly and disproportionately reduce the power output, ancillary systems will be non-trivial. The systems that convert that lousy DC power into quality AC are not going to go down much in cost, because that technology is pretty mature.

    Furthermore, because the systems discussed so far have no energy storage, full power grid connections are still required, and those have a cost. I suspect that if lots of people started using on average quite a bit less energy, but on certain days made high demands on the grid - all at the same time for a given area - the utilities would have to pass on some significant costs.

    There are too many alternatives for PV to be a likely sensible solution except in areas where grid power is unusually expensive due to transmission line capital costs.

    OTOH, given the irrationality of our government, they may turn out to be very good for individuals - who may get a huge subsidy just as the electrical costs soar out of sight due to CO2 emissions, higher oil prices resulting from environmental restrictions, and other government meddling. However, as was shown in the late '70s, those imbalances don't last all that long.

  7. Roy:

    Good points, John. I did neglect the cost of maintaining the power grid as backup, from power plant thru distribution, with all assocated infrastructure and personnel. Coyote has done an excellent service in detailing the reality of this necessity and you a service in reminding of it. This is certainly a non negligible cost, even if typically (as I did) forgotten. My error.

    On the other hand, I wonder how much of Loughlin's $10K per kwh is for energy storage? Nor was I talking about a PV system in a poor case scenario, where it becomes increasingly self evident that it cannot compete with conventional means.

    Bottom line: probably the PV efficiency has to improve much more and the production cost decrease much before PV can compete. That is reality. But what are those numbers? What are they when one factors in the need for that conventional system back up? These are the values that ought get presented to discussion in the public square. They will help make the case for just how unlikely PV is as an economic option.

  8. John Moore:

    I did a little looking around the same time as Coyote. AFAIK we
    Thanks, Ron. I don't have a hard handle on the numbers at this time, but AFAIK we will will shortly be at the point where the cost of cells is not the dominant cost. We may see cells below $1/W + install costs + electronics. Right now, I think you can get a system for maybe $5K/kw, not counting installation or any storage.

    I was especially interested in storage, because my interest was initially started by living through yet one more of our frequently power outages. Then I read a novel about a possible EMP attack, which brought home the dangers I had previously only read about in non-fiction. This led me to contemplate full solar, until I realized that to fully power my house from solar would require a >100kW installation. I also live in a good solar are - Paradise Valley, AZ (a few miles S of Coyote).

    Storage is a real problem. Batteries have limited life times (although we kept a mountaintop system going on float for a couple of decades). Solar system batteries also have to be deep-cycle, which adds significantly to the cost - not the least because it takes you away from commodity auto batteries.

    You are right - it would be good if the public discussion of PV considered these issues. But then, it would also be nice if we had a media that was intelligent, reasonably educated in science, and not in the pocket of the environmentalists and leftists. Sigh.

  9. Keating Willcox:

    Maybe nanosolar, but h/t wikipedia

    Nanosolar does not publicly disclose the wholesale costs of its modules.[24] The company's cost and efficiency claims have been treated with skepticism in some quarters.[25][26][27][28][29][30] Concerns have fallen into two main areas:

    1. Product cost. Nanosolar claims to have produced "the world's lowest-cost solar panel."[31] This cost has been variously reported as "cell costs [of] only $0.36 per peak watt,"[32] a "raw uninstalled cost of solar electricity [of] about 40 to 60 cents per watt,"[26] and an "aim to produce the panels for 99 cents a watt."[33] It has been reported that Nanosolar CEO Martin Roscheisen declined to comment on the $0.36 per peak watt figure.[25] It should be noted that a cell cost of $0.36/watt is consistent with a wholesale solar panel cost of $0.99/watt and Nanosolar has not been criticized for being inconsistent in its claims; rather, skeptics have expressed doubt that Nanosolar can produce a product at the costs claimed in the foreseeable future.[25]. Meanwhile, thin-film competitor, First Solar, has announced the achievement of $0.98/watt panel production cost[34]).
    2. Technological approach. Proponents of high-efficiency crystalline silicon solar cells have criticized the thin-film approach to photovoltaics for its lower power conversion efficiencies, arguing that high power conversion efficiency is more economically advantageous to a complete PV system than are the reduced material costs that typically motivate thin-film approaches like Nanosolar's.[35][36] Thin-film proponents argue the converse.

  10. Keating Willcox:

    Cool Earth Solar has cheap concentrated solar that may be as cheap as coal. Once that happens, it is a tipping point, as utilities will simply subsidize these solar devices rather than expand coal generation. Excess power can be used to generate bio-fuels and bio-diesel. The cost per peak watt has been dropping and will soon be as cheap as coal. Some of the newest algae based systems remove CO2 from smokestack exhaust as well.

    Remember, the first Phoenicians were high tech for their time. Their colony at Carthage had five story buildings, running water, and massive docks. They sailed and traded all over Europe and Africa, centuries before Rome.

  11. Rick C:

    The dirty little secret here is that if you want to not spend $40,000 on solar, you need to drastically cut back your electricity usage. There've been people using panels for 30 years in your part of the country, but their usage is far less than the 475 kwh figure mentioned in the article a previous commenter mentioned.

    Also, I've seen people who actually have used solar panels for a long time say that the lifetime is closer to 30+ years than the 20 or so they're typically rated for.

  12. John Moore:

    Rick C - unless you have a home pre-designed for extremely low heat conduction, AND you like living in 90 degree temps, you need a lot of power here for air conditioning (or, if you can take the humidity at 80+ degrees, you can use a lot less but use water instead using evap cooling).

  13. Rick C:

    John Moore: yes, I'm aware of the power requirements. I have lived in Florida and Dallas for something like 5 years, and I've been to Phoenix.

    There're people, primarily in Taos, NM, but spread around the country, who've built rammed-earth homes with (small) solar electric setups, sans AC. I certainly wouldn't want to try it in a conventionally-built stick-frame building.

    Also, as I mentioned in my first comment, these guys are usually using very little amounts of electricity, with all that implies. But I've seen ROI quotes in the range of 17 years, which, if accurate, is not too bad if you're going to live somewhere for upwards of 25 years. Grab a copy of the magazine Home Power some time, or google 'earthships'.

  14. John Moore:

    If you can get financing such that such that you realize the ROI immediately as a positive difference between reduced power bills and the cost of the financing, then it's cost effective.


    I would love to live in a highly energy efficient home, and hope to achieve that next time I move (if I can ever sell given the market).

  15. Rick C:

    A lot of the people who're building these kind of houses think differently than the rest of us: a rammed-earth house using tires as the wall form can be built a LOT more cheaply. There's people all over the country (admittedly not in huge numbers) doing these things, and sometimes spreading construction over years, and winding up without financing. The nice thing about a solar-electric system is that it's easy to build it in stages, a panel here, a couple of batteries there.

    It's not for most of us, tho.

  16. rxc:

    My sailboat has large solar panels, a windmill, an AC genset, a high-output alternator on main engine, a shore-power connection, an inverter, LOTS of electronics to watch what is going on, various switches and protection devices, and 7 very large lead acid batteries that need to be tested regularly. I am an engineer and I can make it all work, but even I have been known to parallel the inverter with shorepower (the inverter loses when it tries to compete with 57 nuclear power plants).

    I don't see how anyone can expect this sort of system, which is really what you need if you want to live a modestly-reasonable life, to become commonplace in the US. You need to ask yourself - could my aging mother run this system by herself?

    "It's not for most of us, tho."

    Understatement of the year.

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