Final Comments on Solar Posts

I am going to be offline for a few more days, enjoying some time with the family. In the interim, Tom Standing has sent some detailed replies to some of the comments following his posts Arizona Solar Power Project and Ambitious Solar Plans in France.


Here is some additional material in response to a few of the comments that were submitted regarding my essays on the solar project in Arizona and the solar plan for France.

First is a general comment about my intent with the two essays. I am merely attempting to contribute some hard-edged reality to many solar proposals that do not seem to have been adequately appraised through the conceptual engineering process. The value and scale of proposals for renewable energy projects will be demonstrated through the laws of conservation of energy and thermodynamics. Rational calculations employing these laws are what I am basing my analysis on. We have at our disposal an immense database of solar insolation data on the NREL website, from which we can estimate how much energy a solar project is capable of delivering, and how the energy would be distributed with respect to time. I have also attempted to describe reasonable assumptions to fill in gaps of data or other information in order to complete the calculations. I fully realize that reasonable people will disagree with some of my assumptions, but I think that the differences will not significantly alter the conclusions.

Someone offered energy consumption by a range of vehicle size: one megajoule per mile at highway speeds for light vehicles, 2 MJ for heavier vehicles, and 10 MJ for 18-wheelers.

May I suggest we convert these numbers into units that we are familiar with, such as miles per gallon? A few key conversion factors can be used, as follows.

  • 1 joule/sec is the definition of 1 watt; therefore one kilowatt-hour is 3.6 million joules.
  • The heat equivalent of electrical energy is about 3,535 Btu per kWh (100% conversion).
  • Therefore, 1 Btu = 1,020 joules.
  • The heat value in 1 U.S. gallon of gasoline is 125,000 Btu.
  • The heat value in 1 U.S. gallon of diesel fuel is 138,000 Btu.

Working out the numbers, 1 MJ = ~ 1,000 Btu, which is 1/125 gallon of gasoline, which, according to the original comment, light vehicles could travel 125 miles/gal.

At 2 MJ/mile, SUVs would travel ~ 62 miles/gal.

The 10 MJ per mile for 18-wheelers burning diesel fuel calculates out to 13.8 miles/gal. Are these reasonable consumption rates? Most people would expect vehicular fuel consumption to be substantially higher.

The same commenter opined: “if a one square meter heterojunction panel can squeeze out 1.6 kWh = 5 MJ a day…”

Let’s estimate what the conversion of insolation to useful electricity would be for this panel, using NREL insolation data.

California’s Mojave Desert offers the highest annual average insolation of any of the 239 monitored stations in the U.S. – 6.6 kWh/ (m2-day) for unshaded fixed panels facing south, tilted at an angle = local latitude. If the panel yields 1.6 kWh of useful electricity in a day, then the conversion factor = 1.6/6.6 = 24.2%. If that same panel were exposed to insolation in St. Louis, MO where, with the same panel orientation, average annual insolation is 4.8 kWh/ (m2-day), and yields 1.6 kWh/day, the conversion factor = 1.6/4.8 = 33.3%. That would be a pretty good panel!


Here is my response to another comment about the French solar plan. The comment was by Bob Lynch, December 22 at 7:43 PM. He wrote: “The French though DO HAVE areas that bask (Basque?) in cloudless days, week after week. France has a strong infrastructure to deliver power far from where it is generated, so it does not have to be on millions of 17th century homes and hovels that dot the countryside.”

This, then, is my response:

If I interpret Mr. Lynch’s vision accurately, he believes that France could construct a major portion of their solar arrays in their sunniest regions, and then transmit the generated electricity to the populous regions where the climate is less favorable to collecting solar energy.

We can check the validity of such a proposal with the insolation data posted on the NREL website.

Click the link “In alphabetical order by state and city.” Then choose any city to obtain the data in spreadsheet format.

The insolation statistics I use here are for flat-plate collectors facing south at a fixed-tilt angle equal to the latitude of the site. This orientation gives the optimum solar exposure for fixed flat plates. Most installations will not match this ideal orientation. Collectors are tilted at varying angles, may not face due south, are not always clean, and may experience shading from nearby buildings or trees. Generally, solar installations generate about 15% less electricity than is calculated from insolation data and the manufacturer’s conversion factor.

Although the NREL data covers 239 stations in the United States, we can closely approximate insolation in France with comparable locations in the U.S. based on equivalent latitude and similarities in climate. The southern-most part of France, which provides the highest insolation, is in the range of latitude 43 to 44 degrees. A comparable location where the climate features “cloudless days, week after week,” is Boise, Idaho, latitude 43.57 degrees, with a semi-arid climate. The NREL data shows powerful insolation during the 6 months April through September of 5.8, 6.2, 6.5, 7.0, 6.8, and 6.5, respectively, in units of kWh/ (m2-day). The 30-year annual average is 5.1 (same units). I think we can say that there are scant areas in France where insolation would exceed that of Boise.

The insolation that I estimated as an average for France is 4.6, which, I think, is a fair representation of the regions where solar is most apt to be developed.

An important fact that we need to keep in mind is that average annual insolation does not vary greatly over wide reaches of the U.S. Similarly, variations in Europe would be narrow. For example, Sioux Falls, South Dakota is 850 miles due east of Boise (identical latitude), but with a humid continental climate. However, the 30-year average insolation is 4.8 (same units). It’s a good bet that across the southern quarter of France, insolation would be in the 4.8 to 5.1 range, hardly a bonanza for solar development.

Some 260 miles north-northwest of Boise is Spokane, Washington, latitude 47.63, the latitude that is about 80 miles south of Paris. Summer insolation in Spokane is generous, but noticeably below that of Boise: the 6 months April – September: 5.2, 5.6, 5.9, 6.5, 6.3, and 5.7, respectively. The 30-year annual average is 4.5. Spokane’s insolation is, therefore, likely to be near that of Paris and across the northern third of France. Thus, the 11 or 12% difference of insolation in France, between the sunniest south and the north, is probably not sufficient to justify transmission of large quantities of electricity. Solar-generated electricity would best be utilized near the source.

38 thoughts on “Final Comments on Solar Posts”

  1. Robert,

    Current world population is about 6.7 billion, projected to be ~9 billion by 2042.

    If each of those new 2.3 billion people operates only one 60 watt bulb, that would mean the world’s electrical generation capacity would have to increase by 138 gigawatts in the next 33 years to meet their needs. (And that’s only if they consume 60 watts apiece. Humans being what they are, they will all want to consume much, much more.)

    Just to meet the very basic needs of 2.3 billion new people, the world would have to build 92 x 1500 MW coal-fired or nuclear plants in the next 33 years.

    At the present trajectory, solar can’t even replace what we have now, let alone what we will need to handle population growth.

    When will people come to the realization that the real problem is over population?

  2. Clouds are more important than latitude. They make solar electricity at the south pole. Still since France isn’t known for being a desert, I wouldn’t expect it to be a particularly good place for solar power. Germany is the second largest producer of solar power (to Spain) and not a particularly good location for it. Government policy can overcome physics as long as the taxpayers are paying for it. For historical reasons, nobody wants the Germans to have nuclear material, so they make do with what little sun they have.

  3. 92 power plants? That is nothing.
    We just wasted $1 trillion in Iraq. A new power plant costs a bil or two. That’s 500 power plants.
    I have nothing against population control. But between nukes, wind, solar, geothermal we can generate plenty of power.
    Besides, you are preaching to the converted. It is Latin America and Africa that need to reduce population growth. Something tells me that the Brazilians and Nigerians are not reading this blog for hints on Planned Parenthood.

  4. “92 power plants? That is nothing. We just wasted $1 trillion in Iraq. A new power plant costs a bil or two. That’s 500 power plants.”

    It’s not the cost, it’s that there are no plans to build them, and that’s just for a minimum use of 60 watts per new person.

    If they use power at the rate you and I use it, the number goes way up. The average house in the U.S. draws about 1300 watts at any one time. That’s 22 times the minimum of 60 watts those 2.3 billion new people used in my example.

    If they want to use energy at the same rate as we do, that would mean 92 x 22 or 2,024 new 1500 MW power plants in the next 33 years. (That’s 61 generating plants that someone should be building somewhere every year for the next 33 years ~ if they want to live the lifestyle we do.)

  5. Of course more than one person lives in a house. I overlooked that. But, it’s still a lot of new electrical power plants.

  6. Wendell-
    I don’t see the impossibility of building a couple thousand power plants. $4-5 trillion, probably less as labor costs are less in most countries.
    Do we want to waste our money on parasitic wars, military and religion and churches, or build hospitals, power plants etc.

  7. Considering that France is so much sunnier than Germany, I don’t think quibbling over how sunny France is, is worth terribly much, since Germany has done what France said they hope to do by 2020. If France fails where Germany succeeded, it will be failure caused not by the realities of physics and engineering, but caused by economic realities of the lower feed-in-tariff, as Laurent Guerby pointed out.

    But since it seems to be of interest… take a look at a map of the annual insolation in France. It seems to range from 1600 to 3000 solar hours a year. Divide this by 365 days per year, and get a daily insolation of 4.3 to 8.2 kWh/m^2-day. That’s a whole lot more than just a 11 or 12% difference, and may be worth the effort to transmit the power from the French Riviera to the cities. I’m suspecting these numbers are for flat plate no-tilt. So flat plate with tilt at latitude could be higher.

  8. Wendell Mercantile said
    If they want to use energy at the same rate as we do, that would mean 92 x 22 or 2,024 new 1500 MW power plants in the next 33 years. That’s 61 generating plants that someone should be building somewhere every year

    China’s doing more than that right now. At least the claim is that they’re building about two huge coal power stations a week. Many hands make quick work.

  9. “Solar-generated electricity would best be utilized near the source.”

    Algeria has plans to export solar energy to Europe. Maybe not so efficient,but Algeria’s hooked on energy export dollars. And they know the oil won’t last forever.

  10. Robert,

    I may not be understanding your conversions, but it seems like you are making one wrong assumption.

    “The heat equivalent of electrical energy is about 3,535 Btu per kWh 100% conversion)”

    It seems like you took the thermal energy of gasoline and then directly compared it to electrical energy or work energy, when in fact you lose most of the energy in gasoline to waste heat.

    Perhaps the previous poster should have specified what ‘quality’ of energy he was actually describing by their estimates, however I would have interpreted them as work or electrical energy and not thermal energy.

    Assuming 25% avergage efficiency for your engines:

    Light vehicles could travel 125 *0.25 = 31 miles/gal.

    At 2 MJ/mile, SUVs would travel ~ 62 *.0.25 = 15.5 miles/gal.

    The 10 MJ per mile for 18-wheelers burning diesel fuel calculates out to 13.8 * 0.25 = 3.45 miles/gal.

    These numbers are much more in line with expected values.

  11. Congratulations again to Tom Standing. Good responses, based on facts & physics.

    The reaction to mr. Standing's responses is deeply interesting — with a few honorable exceptions it might be summarized, How many different ways can we ignore what he is saying?

    Oh well! The laws of physics will win in the end. They always do. And government subsidies will end, as they too always do; just ask the crowds in Rome when the Empire last delivered Bread & Circuses.

  12. In forward order:

    Robert, thank you for the attribution. I was both “a person” in your first paragraph (referring to megajoules) and the “Bob Lynch” in subsequent paragraphs.

    Citing [tournementmonkey], the energy calculations you did DO need to be tempered by thermodynamic efficiency. 1 MJ/mile is about 32 miles/gallon, just as 10 MJ/mile is about 3.2 … which corresponds very closely to the all-fleet averages of the world. I chose MJ as the standard, because when talking about kilowatt-apples, and trying to compare them to imperial BTU oranges, well … MJ is just a nice central unit of measure. But the Berkeley in me says, “whatever we like!” and that’s OK.

    Citing [Maury], and citing your paragraphs about insolation-versus-selected-cities … I note that if one were in a jungle, looking for a patch of sunlight, one wouldn’t cast about the swamp. The 1% of “high ground” would be the target. Likewise, the cities of France are in particular cozy and strategically located near GOOD farmland, GOOD riverways, and GOOD places to live. Solar cells, almost by definition excel at utilizing the land that is the least favored … where you won’t easily find statistics, unfortunately. I think that European “choice PV locations” (which are say among the least favored 1% of the land) would average well above the 4.5 to 6.0 kWh/sq.m. (raw insolation) parameter. Probably closer to 6.0 to 7.0. But I apologize for the quibble. Let us move on to the meat.

    Citing [robert (is that you?)], cloudcover is indeed the most important mesoscale factor, apart from the seasonal periodicity of a locale. The choice of arid, desert or near-desert locations on the southern margin of France, Spain, and especially (though admittedly far away) Portugal is attractive.

    The “Algeria gambit” is also a stretch, but deeply motivating. The deserts of the Great Sahara are, in short, amongst the most pristine and seasonally reasonable places on the planet on which one could put tens of thousands of hectares of solar cells, far, far, far from civilization and vandals.

    It may sound uncomfortably like SciFi, but these are the uses for the emerging technologies of superconductive power transmission. Talk until the Pharoah’s themself come to life, but the ever-vetted, ever-bandied “satellite solar” idea simply pales to what a bit of superconductivity and utterly desolate solar fields on Terra Firma could achieve for the same (if not a better) price.

    Let us look at the horizon, and remember that in the modern context … it is pretty close, and emminently cheap to get there. At least compared to Ares V.


  13. The value and scale of proposals for renewable energy projects will be demonstrated through the laws of conservation of energy and thermodynamics.

    Okay, sorry, I hadn’t noticed that Tom Standing has stopped saying that France building 5400 MW of solar by 2020 is “incomprehensible”. Yes, the hard edged reality is that even though France could build 5400 MW of solar by 2020, (just like Germany has done), it will produce very little of the electricity that France uses each year, just like Germany’s solar produces only 0.6% of Germany’s electricity. Even doubling the insolation numbers will not make much difference. 1% still isn’t much. Lower cost, higher efficiency and higher EROEI panels may change the balance in the future, but I wouldn’t count on them by 2020.

    About value and scale, notably, while the plan calls for only 5400 MW solar, it calls for 25,000 MW of the lower cost per kWh, higher EROEI, wind farms.

  14. “I don’t see the impossibility of building a couple thousand power plants. $4-5 trillion, probably less as labor costs are less in most countries.”


    Money isn’t the problem. The problem is finding the fuel for them and controlling the emissions from that fuel.

  15. Fuel? Sun, wind, nukes, geothermal, hydro. Plenty of fuel. Mini-nuke plants, replicable. Breeder nuke plants. Clean coal.
    Building more power plants seems eminently possible, and desirable.
    Also, “the world” can acheive higher living standards using about one-third the BTUs of Americans. From the get-go they install LEDs, shading, etc.
    Living standards will rise worldwide, faster if get rid of parasitic militaries and religions.
    Eisenhower had it right. Every bullet is a mouthful of food out of some infant’s mouth.

  16. “Since when did 1 kwh = 3535 Btu?”

    1 kilowatt hour = 3412.1414799 Btu

    Since I moved from California, I have not worried much about the amount of energy the sun provides in the California desert in the summer time. I also do not care how much hydrogen is in the universe. I do care about the size of the wood pile just in case there is an ice storm that takes electricity for a few days.

    The problem is that too many get obsessed with energy without taking a holistic approach as Benny suggests. Figure out what makes you happy. For me shade trees reduce the solar gain on my house but allow diffuse light in. An attic fan and ceiling fan makes my house ‘feel’ more comfortable in the summer. In the winter, direct sunlight feels good.

    Low-e glass and roof overhags cost next to nothing. I was looking at pictures of new solar subdivision in California, no overhang, no trees, no yard but they had solar panels and BMWs.

  17. I agree that the physics of this are not being properly digested – some of the ideas for solar generation potential and transmission are far fetched in terms of the scale of deployment.

    To the comment about gasoline BTUs vs electric BTU, i think Robert’s point still stands if electric cars are within a certain efficiency range. i believe the idea is to determine how much solar electricity is necessary to replace gasoline.

    if Algeria builds solar plants, i think ultimately they don’t want to export electricity, but rather attract electricity intensive industries (aluminum processing) to be performed at Algeria and then exported, similar to what is done iceland with their geothermal electricity.

  18. Great commentary, Kit P. Exactly. There are tons of high-tech and low-tech solutions to energy consumption.
    Unfortunately, on the supply side I guess it is mostly high-tech, but plenty of solutions as well.
    The worst thing is to become pessimistic. You obviously are not a quitter.

  19. To the comment about gasoline BTUs vs electric BTU …

    These issues tend to be much more subtle than too many of the products of the modern educational system assume.

    Efficiency in transportation energy use is not just a matter of energy use in the drive train. There are many associated energy demands to consider — keeping solar panels clean, storing electrical energy, building transmission systems & roads.

    But consider only the energy use in the vehicle itself. Thermodynamically, part of the energy released by gasoline combustion is rejected. But is it wasted?

    In the winter-time, driver safety (as well as comfort) requires that the cabin be heated — which the fossil-fueled vehicle does efficiently by using the thermodynamically-rejected heat.

    The putative electric vehicle avoids rejecting any energy in converting stored electrical energy to mechanical motion. Therefore, the electric vehicle will need to use additional stored energy to keep the driver warm enough to be capable of functioning safely. That energy has to be included in any apples-to-apples comparison.

    Yet another argument against letting under-educated lawyers write technology mandates to be imposed by unthinking politicians.

    Happy New Year!

  20. Happy New Year to all.
    Next year promises to be a toughie; I sincerely wish prosperity on all, including my friendly “foes.”
    Look for $10 oil next year, when it gets close, you might think about a dividend oil stock, such as Royal Dutch Shell. A long-term hold, but you get a divvie for the wait.
    And as bad as next year gets, remember that in general man seems to be able to make the world a better place through the generations.
    Free markets and well-educated peoples can overcome any obstacles, even if lawyers try to flummox us.

  21. When will people come to the realization that the real problem is over population?
    When will some of us accept that Robert Malthus has been wrong for 150 years, and can thus be expected to continue doing so for the foreseeable future?

    The problem with The Principle of Population is that it treats all those new humans as monkeys that somebody (a Harvard trained American, perhaps?) needs to look after. Bit of a racist point of view, won’t you say, Wendell?

    In reality all those new humans come with all the talents to survive regardless of their circumstances. As Jared Diamond implied in Guns, Germs, and Steel, if you like new technology, more people is the best way to get it. More people means more challenges, but also the means (aka human ingenuity) to overcome those challenges.

    As I stated before, the planet cannot support 6 billion hunter-gatherers. But 6 billion users of the Internal Combustion Engine (ICE) somehow manage to survive. That does not imply that we need to become 9 billion users of the ICE by 2042. As the planet’s population grows we’ll need ever more sophisticated technology to accommodate everybody. Want to increase the masses’ standard of living? Even more technology then!

    Of course, some of that 6 billion is doing a lot better than others. The differences are mainly related to culture (with apologies to the American culture of political correctness, where one can never say such a thing) and political leadership.

    Some cultures teach the individual to take responsibility, get off his behind and do something with his life. Others teach the individual to accept his fate in life and stop whining about it. The difference is obvious.

    So stop worrying about meaningless metrics such as the number of people on the planet, Wendell, and start thinking about how you can reduce your own footprint (and save some money). Chances are, if you come up with something truly useful, that it can be copied 6 billion times…

  22. Mandates and incentives work when it is practical to achieve the goal. Ethanol is being produced at a rate in the US that is limited by the capacity POV to use it. To increase, more dual fuel vehicles will have to be sold.

    What can not be mandated is what consumers buy. You can try to make me buy an EV, an E-85 POV, or solar panels on my house. However, I can try to remove you from elected office. It is called a voter mandate.

    When mandates are placed on electric utilities, then the consumer no longer has a choice.

    It is easy to determine how much electricity can be produced by mandates. Multiply the manufacturing capacity (MWe) by the capacity factor (CF) by the number of hour in a year to get MWh.

    Typical real world capacity factors assuming electricity was needed 100% of the time:

    Wind – 20% (45 % achievable)
    Solar – 5% (30 % achievable)
    Coal, NG, oil, nuke, geothermal, biomass – 90% (95 % achievable)

    Transportation of fossil fuel and biomass limit production to a degree.

    There has never been a limitation on the manufacturing capacity of coal, NG, oil, nuke, biomass. However, there is limitation the manufacture of equipment of wind and solar.

    Wind and solar will be an insignificant part of the world supply of electricity for at least the nest 50 years. Every plot of world electricity supply shows wind renewable energy ‘other’ only show it being a dark line above the rest of the supply.

    So what happens when bad public policy dictates mandates higher than reasonable? Most of the wind turbines and solar panels get erected in the US because we are a rich country and can pay more for the equipment.

  23. @Clee

    My numbers come from years of critical observation. Those of who make electricity professionally are proud of performance. It is something we brag about.

    Clee is good at finding links but I doubt he can find one to contradict me.

  24. I doubt I can find worldwide figures for actual solar capacity factors, so I decided to look for numbers for Germany, which is not the sunniest of countries, and I found
    which shows the large PV plants in Germany getting capacity factors of 10% to 13% and one outlier at 23%. That’s at least twice the 5% you’re pulling out of your head. Now I don’t know how much to trust wikipedia, but I have even less reason to trust your number. And while these are the largest of the plants, the largest plants will tend to have a large effect on the averages.

  25. Or try the iea, which I trust a bit more than wikipedia.
    2007 New installed power: 1100 MWp
    2007 Total installed PV power, 3800 MWp
    2007 PV power generation 3000 GWh

    Assuming that all 1100 MW of PV installed in 2007 was installed on January 1, 2007 at 12:01 am, that would result in a capacity factor of 9%, which is still almost twice your 5%.
    Assuming all that 1100 MW of PV installed in 2007 was installed on December 31, 2007 at 11:59 pm, that would be a capacity factor of 12.7%. The reality is somewhere in between, which agrees with the numbers in wikipedia.

    For France,
    cumulative installed PV
    end of 2005: 33.0 MW
    end of 2006: 43.9 MW
    2006 PV power generation, 44 GWh
    which results in a capacity factor of 11% to 15%, (again depending on when in 2006 the new PV came online.) which is two to three times your guestimated capacity factor.

  26. Clee, you are missing the point. If I ordered a ton of dry oak fire wood, you would expect a certain heating value to meet my needs in the winter. If Clee delivered one load of green pine in a ½ ton Ford Ranger, I would to either run out of wood before the end of winter or have chimney fire.

    Since Clee lives in California and is a victim of poor education system, I would not expect him to understand and I would educate him. California is a state where being honest is not a good way to stay in business. Honest firewood dealers would give you a price for dried hardwood split and stacked next to your house. They would also give you a price for green hard wood that you can cut and stack for next year.

    The point is that there is an established method for documenting performance. While Clee did a good job of researching the solar industry carefully crafted lie, but Clee failed identify the crafted lie choosing to suggest that my analysis is not dead bang on.

    Clee did not present any production numbers numbers only only claims by manufactures of what they expect. This strangely odd since you get paid by the number of kwh you produce. I am going to pay the fire wood dealer by the number of BTU delivered to my house not the number of chain saws he owns.

    My estimate of solar PV CF is based on performance data. I have one utility system designed for 20% that does 19%. A second data point is designed for 20% that does 13%. Many designed for 20% that does less than 5%. Many, many systems do not work at all.

    You do understand Clee that is the responsible of the seller document performance especially if you are claiming your product is better?

    So how are the others doing?

    “US, average capacity factor for nuclear is around 90%”

    This based on actual performance data. The design CF of the 104 operating nukes is 80%. In France, CF of nukes is about 77% which is lower because France uses nukes for load following.

    “Typical real world capacity factors assuming electricity was needed 100% of the time:”

    Again the point is not who has the prettiest girl friend but who is better at getting the job done when the essential task is producing electricity.

    In France if more electricity is needed, nuke plants CF will approach US nuke plant CF. In the US, if more electricity is needed, coal plants CF will approach US nuke plant CF.

    “natural gas combined cycle was 38%, petroleum was 13%, and other natural gas was 11%”

    In each of these cases, CF is based on the need for electricity not ability of the equipment.

    So Clee, after the rolling blackouts in California, what was done? More gas fired power plants were built.

    So what is the root cause of solar not producing more electricity. Even using Clee’s CF, Germany gets 0.5% of electricity. Move the PV to the US southwest, it could be 1% of electricity. Since AGW is a global issue does it matter where the electricity is produced?

    So if the goal is to reduce fossil fuel use, the performance indicator should be how much fossil fuel is used. While California and Germany talk about wind and solar, it is to deflect attention to increasing reliance on fossil. While it may be counter intuitive, replacing old coal plants may have the better results in ghg reduction.

  27. Kit P writes:
    Since Clee lives in California and is a victim of poor education system

    I live in California, but I didn’t grow up or go to school in California.

    Maybe I’m missing your point, but it seems to me your dreamed up 5% capacity factor for PV is the lie, not my researched numbers. I chose Germany and France because they have feed-in tariffs which the countries pay for, so (unlike the US) they meter how many GWHs are coming from PV and entering the grid. They also know how many MWs are connected to the grid for the purposes of claiming the feed-in tariffs. So I get numbers like 10% to 15% in Germany and France. The numbers were based on production numbers. If they were manufacturers/installers theoretical numbers, you’d see numbers more like 15%-25%, and that’s what I think that suspicious 23% outlier is on the wikipedia page.

    “Typical real world capacity factors assuming electricity was needed 100% of the time:”

    Very curious wording. In the real world, electricity is needed 100% of the time. Never does the load/demand drop to 0. And it’s weird that you seem to think that actual real life performance data for capacity factor is somehow not “real world”. If solar can replace the non-combined-cycle natural gas actual needed capacity factor of 11%, that would be nice. For now of course, there isn’t even enough PV capacity to reach that limit, much less try to get it to retire base-load plants.

    Yes, after the rolling blackouts in California in 2001 more gas fired power plants were built. The root cause is of course PV is still way more expensive than natural gas plants. Economics.

    I don’t care to challenge here why California or Germany or France talk about wind and solar energy. Maybe they have lousy reasons. I’m just challenging the 5% capacity factor for PV that you can’t show is real.

  28. “But 6 billion users of the Internal Combustion Engine (ICE) somehow manage to survive.”

    The world does not have six billion users of the ICE.

    Perhaps one-sixth of the world uses ICE’s at the rate we do. (U.S., Canada, Australia, Western Europe, Japan, plus limited parts of South America, South China, China, and Africa.)

    About two-billion more of the world’s population uses ICE’s, but at a much lower rate than we do.

    And for about the bottom half of the world’s population, using an ICE is only a dream, other than perhaps for an occasional ride on a diesel-powered bus.

    The real problem is how we handle the aspirations of that bottom half. There is obviously not enough fossil fuel for 6.7 billion people to consume at the rate we do.

    How do we tell those at the bottom there will never be enough for them?

  29. Clee, you are confusing projections with actual measured numbers. You did not read or check the references provided. You provided CF for some plants that are not even built yet.

    Yes the numbers exist, no they are not publishing them. I happen to think my estimate is better than the estimates that you provided. Yes, Clee you are being lied to, but it is not me that being dishonest.

    “Yes, after the rolling blackouts in California in 2001 more gas fired power plants were built. The root cause is of course PV is still way more expensive than natural gas plants. Economics.”


    “For now of course, there isn’t even enough PV capacity to reach that limit, much less try to get it to retire base-load plants.”

    Which is it Clee, PV is too expensive or too insignificant?

    I want you to do something for me Clee and then maybe you will understand. Pack a picnic lunch and drive east on Twin Cities Road from highway 99 to Ranch Seco park. Visit your favorite PV solar farm then look west and what do yo see? Google Earth and MSN both provide satellite view. You will see a closed nuke and the gas fire power plant that replaced it.

    Now find Ed Smelloff and S. David Freeman. Ask them where all the solar systems are that they said would replace the nuke plant they worked so hard to close. Clearly SMUD has lots of land between their newest PV system and the lake. SMUD claims to be a leader in solar but when view from a satellite, SMUD is saying one thing and doing another.

    So Clee take your number for CF and your number manufacturing capacity, do you get a really small number? Every kwh produced by PV is a kwh not produced with natural gas.

  30. Which is it Clee, PV is too expensive or too insignificant?

    PV is insignificant because PV is currently too expensive.

  31. Exactly!! And why is PV too expensive? Because it does not work and is unreliable. Why was Rancho Seco too expensive? Because it was unreliable. Today every remaining B&W reactor is running well and producing cheap electricity for customers.

    My main problem with the solar industry is that it is focuses on selling junk rather than making electricity. Germany has a feed in tariff. While this is clearly doing a good job of promoting installing PV in the wrong place, no one has provided data on the experiment. Is PV good for the consumers or just good for the junk peddlers?

  32. There is obviously not enough fossil fuel for 6.7 billion people to consume at the rate we do.
    No, not at current prices. But as the events of the past summer showed, with the right price signal, even we use less fossil fuel. Sounds like a self-correcting system to me: demand goes up, prices go up, demand comes down again.

    The real problem is how we handle the aspirations of that bottom half…. How do we tell those at the bottom there will never be enough for them?
    We don’t tell them anything, since we are not the people denying them access to the ICE. See local corrupt politians for that.

    And don’t buy the there will never be enough nonsense, because so far there somehow always has been enough. I suspect the reason is innovation: you know, when upward prices stimulate an entrepreneur to come up with a more efficient way to get things done. Such as when the invention of the ICE saved London from getting buried under horse manure…

  33. Tom is on vacation, but sent me the following replies to various comments:


    A couple of recent comments on my solar essays deserve responses.

    A comment from “tournamentmonkey” on December 30, 5:27 AM wrote that I did not account for the loss of energy in a gasoline engine when I converted 3,535 Btu per kWh in a 100% conversion between electrical energy and heat.

    TM would be correct if I was estimating the kWh that would be generated through the combustion of a certain quantity of fuel with a specific Btu content. After all, gas turbines and steam plants generate electricity at varying “heat rates” ranging from maybe 5,000 Btu/kWh to 12,000 Btu/kWh. A gasoline engine running a generator would likely operate at around 10,000 Btu/kWh.

    However, that is not what I was doing in my calculations. I was merely converting a given quantity of energy from megajoules into Btu, as represented by the heat content in gasoline. On December 21, 5:31 PM Bob O’Lynch wrote that power demand for light vehicles is about 1 megajoule per mile, for SUVs about 2 MJ/mile, bobtail trucks about 5 MJ/mile, and 18-wheelers 10 MJ/mile.

    By specifying vehicular power demand, Mr. O’Lynch had already included the heat loss for internal combustion engines. I merely wanted to see what his power demand in megajoules would be in gallons of gasoline or diesel. That would require converting kWh directly into its Btu equivalent on a 100% basis. Now, a few people quibbled over what the Btu/kWh should be. The conversion factor might vary slightly depending on the reference; I’ve seen numbers ranging from 3412 to 3535. I happened to use the higher number, which barely affects the third significant figure. Big Deal!

    Some commenters still quibble over the insolation figures that I estimated for France. In the absence of site-specific insolation data for Europe, I estimated insolation for France based on equivalent locations in the U.S., for which I received a number of criticisms.

    Fortunately, Clee came to my rescue by providing the link to an excellent insolation map for Europe, including a slice of extreme northern Africa. This map went straight into my solar binder, Clee. Thank you very much! The units given on Clee’s map are quickly converted to units in the NREL database for optimum flat-plate orientations, by dividing by 365 days/year.

    Careful reading of the map shows that a small corner in the extreme southeast of France gives France’s best insolation, which calculates to 5.1 kWh/ (m2-day), exactly the number for Boise, Idaho, the U.S. location that I wrote would be the upper limit for France. According to Clee’s map, the latitudinal band that runs across northern France through Paris has lower insolation than what I had estimated to be 4.5. Clee’s map shows the insolation to be 3.6 kWh/ (m2-day), the same as for Seattle-Olympia, the poorest regional insolation in the Lower 48. But don’t bet on solar arrays along the French Riviera transmitting meaningful quantities of electricity toward Paris in our lifetimes.

    For most of Germany, insolation (according to Clee’s map) is 3.4 kWh/ (m2-day), which is the same as Quillayute, the rain-swept, foggy weather station on the northern Washington coast, boasting the poorest insolation for any station in the Lower 48. Gunter, a longtime friend of mine left his native Germany 45 years ago for the San Francisco Bay Area to escape the dreary cloudiness. Good luck Germany, with your solar program at 14% capacity factors.

Comments are closed.