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The future of solar power

  1. May 22, 2017 #126
    Capacity factor in Arizona is 25%, not 20%.

    More importantly, the fact that solar works only part of the time *is already accounted for* in these numbers. Otherwise, capital cost of PV would be $13000/kW, way above everything else, and new solar installations in 2016 would not be the largest segment among all new power plants.

    Business disagrees with you.
    Solar power plants are popping all over US southern deserts, faster every year.
    At the same time, Westinghouse, which constructs all new nuclear plants in US (four AP1000 units) ran into large cost overruns and filed for bankruptcy in March of 2017.
  2. May 22, 2017 #127
    Except that oil is a commodity, traded on world markets. Even if we cut our oil consumption by 18%, how would we specifically avoid oil from the ME? And wouldn't other countries just buy that ME oil, so the end effect is nothing?
  3. May 22, 2017 #128


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    Yes, because they are subsidized. If they would be so competitive, why would they get subsidies?
    Where are the GW-scale commercial battery plants?
    Good for Arizona. Fine, 10%-25%, the former is typical for Germany, for example.
    The study describes a 20 MW plant with inverters that can handle 20 MW, so the 20 MW are the peak power. The cost of this power plant is $53 million (PV fixed, very similar for the others). That is $2600/kWpeak, or ~$10400/kWaverage at 25% capacity factor.

    You have to run the solar panels for 90 years to match the installation costs of nuclear power, and ~70 years if we take the operation costs of nuclear power into account. And that is without storage!

    Edit: Fixed a number.
    Last edited: May 22, 2017
  4. May 22, 2017 #129


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    Agreed, and I'd say that if the goal of the original statement is to make the Middle East irrelevant in terms of their ability to impact prices and politics, we're pretty much already there. In the 1970s OPEC had a significant ability to harm the US/world economy and that played a small role even in the 2009-10 recession. But their 2014 experiment/price war failed and showed that their ability to affect oil prices is extremely limited without severely harming their own economies. And as a result, they are now the ones in a lot of trouble and they have all but resorted to begging:

    So in terms of whether our foreign policy should be impacted by fear of OPEC, that time is over. But like you say, it's a global commodity, so even if we become a net exporter (and likely will within 10 years), OPEC will need to stop pumping oil for it to stop mattering at all.
  5. May 22, 2017 #130
    Right. So they rate it at ~ $2.65/watt, a reasonable number for installed PV. Another way to look at that, if they did account for a 20% capacity factor, then that 20 MW would represent 100 MW of solar panels. That would mean they are paying $0.53/watt (corrected math mistake) for solar installed, and we know that is not a reasonable number.

    @nikkkom - This is what happens when one is so enamored with a particular technology - they see a number that agrees with what they want to believe, so they don't question it. Remain skeptical - of everything.
    Last edited: May 22, 2017
  6. May 22, 2017 #131


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    You proposed leaving all the "existing power plants intact", i.e. the coal and gas plants (fueled instead by hydrogen). That's one. Then you would build another power generation system of comparable size based on solar and wind. That's two. Also, a gas storage system is required, large enough to supply a nation for a month or so.

    BTW, the pipelines in place to transport natural gas (hundreds of thousands of miles) have some H2 mixed in but can be wholly converted to hydrogen. H2 would leak where CH4 won't, embrittles pipes not designed for it, and has a lower volumetric energy density than methane requiring a larger pipe diameter to ship energy at the same rate.
    Last edited: May 22, 2017
  7. May 22, 2017 #132


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    It turns out that storage for intermittent power is required very soon, that is, after a few percent share of generation. As there is already a grid in place to which intermittent power is added, and much of the existing power is slow to start and slow to stop (aka 'must run'), excess power occurs quickly, driving electricity prices to zero and negative where subsidies exist. Negative pricing is already commonplace in Texas (high wind share) and in parts of Europe. Without a large price on carbon or subsidy, new intermittent power is at a price disadvantage with the marginal price of running fossil fuel power, and so forcing the price of intermittent power to be realistic and include the price of storage makes new solar/wind+storage untenable.
  8. May 22, 2017 #133


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    Please make that case. A gas peaker plant in the US serves peak demand more cheaply than (unsubsidized) utility solar and more reliably, and utility solar is far less expensive than residential rooftop solar, and far, far less expensive than rooftop plus batteries.

    Unlikely. The nuclear plant closest to me produces power (O&M) at 1.5 cents/kWh.

    After the financial crisis, Spain cut off its subsidies to solar power for some years. Result:
    Last edited: May 22, 2017
  9. May 22, 2017 #134
    Oh wow, Ontario is Mad about green power. in the attached link is the price schedule for what they call MICROfit (Feed In Terrif for small installations)

    The buy back contracts are guaranteed for 20yrs. Probably is calculated to pay for everything but the land.

    The amount paid back decreases as installation size increases lol i.e. less than 6kw is 0.31$/kwh!!!!!!

    Doing some digging and some peeps who got in years ago have 0.80$ buy back, on the guaranteed 20yrs contract this one case was a loan payback (on equipment & installation I presume) was 6-7 yrs...with the rest being profit. That was a 10kw pv system.
    Last edited: May 22, 2017
  10. May 22, 2017 #135
    I'm curious as to how this is determined. Obviously, solar at relatively low average contributions will have a much bigger effect on the grid during those ~ 6 hours of higher output, very roughly 4x the average. That is offset somewhat, as daytime usage is also higher than night-time. Sticking with my very rough numbers, day demand about 2x night demand. So if we had 10% solar on average, it would be contributing about 20% of the grid power during the mid-day. Maybe more in summer due to seasonal variations, but then again, summer can be high demand with A/C.

    So my question is, how much solar contribution can the present grid handle (I'm thinking NA grid, with relatively little hydro)? Can it accept 20% from solar one day, and near zero the next? Or a drop from 20% to 5% when a cloud goes by? I suppose if day-time energy production is ~ 80% baseline and 20% some form of peaking, it could do it. But I really don't know where those limits lie. Beyond that, we need storage, or install more peakers as we install more solar (and wind), or just let it be wasted. And if the peaks that can't be absorbed only occur a few times a month, and are only a few percent of excess, I suspect it just isn't economical to do anything but waste it.
  11. May 22, 2017 #136
    Would we have gone to the moon on Investor capital? Or create all those inventions as a result? What about military? This is how the economy works, sometimes the gov money is needed to "push" a tech up and over into being economically viable for investment...so now it is...yay to circumnavigating investor nearsightedness.

    Was nuclear brought to fruition on venture capital?

    The GW chem storage is going to happen. China seems to be most active with this. Apparently plans to install 500mw in a single location started in '16...cannot find any mention on progress though.

    That said why the argument on single system capacity? Seems so weak when wires between make such a thing a "system".
    Last edited: May 22, 2017
  12. May 22, 2017 #137
    It is possible to boycott middle east oil, but not really necessary. The other countries who would by from the ME, already are, so they aren't going to increase demand by 18% just to spite us. And the US is hardly the only country that would want to do this. Russia has problems with terrorism too, and Europe would likely take the lead. The result: For a quarter the cost of the gulf war, we dramatically defund terrorism.

    But all the political stuff is beside the point. The original statement is this:

    By my numbers, that seems to work.
  13. May 22, 2017 #138
    I don't think those are reasonable comparisons. Solar PV has already been brought to you by the government military/space program. It is now in the hands of the market to improve value. Efficiency improvements are still being funded at the government level (at least I seem to see a fair number of university programs, I assume grants are involved), but we are already at the point that we can't expect huge increases in efficiency. A single cell panel is theoretical max ~ 32%, and panels are now around 15% I think? And multi-cell to get higher will almost certainly be higher cost, though maybe worth it to reduce installation costs.

    This is kind of a soapbox rant for me, but I think subsidizing sales is about the worst use of funds to promote anything. It encourages sales of the current, less-optimal technology by changing the value proposition for the buyer (paid for by others). What we really want is true value. And that means the technology must be improved. Far better to take those sales subsidy $ and apply it to research. Additional sales of the older product won't do as much for us as developing the next generation, that maybe has a real chance of competing.

    I think sales subsidies could actually be counter-productive. Since it creates false demand for current product, it reduces incentives to reduce costs.

    I come from a manufacturing background. If we were in a low margin product area, it was essential to cut costs and improve manufacturing efficiencies. If you didn't your product died. In a high margin product area, you could focus more on features, customer support, other less tangible area, you were still making a good profit. We were not as motivated to cut costs on the high margin products. In this same way, solar PV sales subsidies effectively increase the product margin (buyers are willing to pay more to the seller), so therefore reduce motivation to cut costs.

    As long as I'm ranting, I recall reading a good article recently - they said that if we are going to have sales subsidies on solar PV, it should be based not on the cost of the installation, but on the energy produced. After all, that is the goal, right? But as it stands, a poor installation that is partially shaded, and on a rooftop at less than optimum orientation, and in a cloudy area of the country gets the same $ subsidy (at least at Fed level) as the installation done in full sun, with proper angles, etc. What a waste of taxpayer funds!
  14. May 22, 2017 #139


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    When it comes to the scale of the energy industry, I don't think 1 MW pilot plants (most are smaller) in Germany qualify as 'getting there' as opposed to propaganda stage props for Energiewende. The US for instance has a very expensive full scale 582 MW attempt at clean coal (sequestered carbon) plant nearing completion in Kemper, Miss. I wouldnt consider this probject as getting close to clean coal, but rather proof of its unfeasibility with current technology.
  15. May 22, 2017 #140
    I cannot subscribe that the ontario PV industry subsidies will retard the progress of PV tech. I would argue that those subsidies have grown to a great extent the current PV industry in Ontario...More panels, batts and jobs.

    If I have old panels that make x amount, why would this stop progress towards a even better pay back? PV is not a trivial thing like a can opener.
  16. May 22, 2017 #141


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    You switched from "solar power is so cheap!" to "we should subsidize it, so it might become viable in the future"?

    How much tax money should we put into solar power, and how much will solar power cost in the future?
    Germany alone invested more than $100 billions for direct subsidies (for power delivered to the grid) already, and commited to pay $150 to $200 billions more in the next 25 years (depending on how much gets installed in the next years). Add various other subsidies and we get a big three-digit billion number. And that is just Germany, many countries have subsidies.

    Compare this to fusion, for example. The international community struggles to find $1-2 billions per year for ITER, and total US funding over the last decades is somewhere below $20 billions (in today's dollars).
    I mean "getting there" in terms of overproduction. Negative market prices are getting common.
  17. May 22, 2017 #142
    That's silly; you've already made the point it is not yet economically viable without subsidies. Should clean energy production sit stagnant? I don't think so, I wanna see it turbo'd with everyone's contribution.

    Now get me one of those NASA miniature Nuclear or RTG power plants!!
  18. May 22, 2017 #143
    Because as I said, it reduces motivation for better panels.

    An analogy - think back to when a laptop computer was a big, heavy, short battery life, small screen 'lug-able' device. They were expensive, and not a very good value proposition, other than for people who really needed portability, even if it meant it was 'lug-able'.

    But manufacturers knew they could increase sales as they improved the value - making them smaller, lighter, cheaper. So they worked very hard at it.

    Now consider an alternate universe where the government decided to subsidize lug-able computers, to grow the market. We will use an extreme case to illustrate, but assume the subsidy was so great, that people bought them even if they didn't have a great need for portability. The manufacturers could sell all they could make. They had no motivation to improve them, they had a market, provided by the government subsidy. So advancements were not as fast as when those companies had to improve the product to increase sales.

    Personally, I'd be thrilled to buy into a solar farm, if the numbers would work. But I still feel that solar has to come down in price to offset the risks to my investment.
  19. May 22, 2017 #144
    Generating power with solar is "so cheap", compared to those requiring maintenance, infrastructure. We should subsidized it to compete, from an installation perspective, with the Multi billion dollar head start that traditional means has over solar.

    The are a silly amount of in-calculable costs associated with traditional power generation.

    Show me one instance of a purely venture capital funded nuclear power plant.
  20. May 22, 2017 #145


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    Several factors include curtailment of wind and solar (throwing away extra, i.e no return) and the marginal cost or running dispatchable power plants (ie gas) that *must* be in the grid without storage.

    Wind for instance devalues to about 85% of its original value at 10% grid share. Solar devalues much faster.

  21. May 22, 2017 #146
    First, I do not accept that sales subsidies can "make or not make anything economically viable". A thing is economically viable or it isn't, based on cost versus what it produces/saves. A sales subsidy only changes who is paying for it, and that's a political decision, not physics or economics.

    Why do you ask me if I think clean energy production should sit stagnant? Re-read my posts, I've said there is far better use for money to promote green energy than sales subsidies. I say that anyone who wants to promote clean energy should be against sales subsidies, and for more effective means of bringing clean energy on line.

    And it isn't always a measure of pure, hard $. We might decide, as a nation or community, that it is OK to run a solar farm at a loss if we need to, because we feel (and hopefully can back it up with reasonable numbers), that the pollution reduction is worth the $ cost. Fine, then let's do it. But then just let the taxpayers share in funding that solar farm (and share in benefits if it is economically viable), which as we've determined can be installed far cheaper than individual rooftop solar, rather than providing a subsidy to an individual, who maybe benefits personally with reduced electrical costs, at other's expense. And since that residential rooftop solar is unlikely to be as well placed as a solar farm, the taxpayer gets less green energy for their $. It's lose-lose for everyone. We should just stop it!
  22. May 22, 2017 #147
    Today the thin laptops are more expensive than the thicker ones, both continue to improve. early adopters are always a thing.

    I don't know what motivation means if not "increasingly better PV's systems".

    It's a profit / square foot thing driving the innovation.
  23. May 22, 2017 #148


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    All of the nuclear reactors just finished (Watts Bar II) or under construction (Vogtle 3, 4 and Virgil 2, 3) in the US were funded by their owners, either private or local municipalities, as is done with other power plants. See here for Vogtle. The US government funds general research on all kinds of energy technology, including nuclear. The US government also offered to *guarantee* the private loans to Vogtle and Virgil, incurring some risk to the treasury, but this has so far inccurred no cost to the taxpayers. This has been the model for most (if not all) of existing US nuclear reactors. All US nuclear operators also i)pay for private insurance and ii) pay into a trust which funds eventual decommisioning and a waste depot.
    Last edited: May 22, 2017
  24. May 22, 2017 #149
    ?? What ever you want to call it at the end of the day, government intervention can sway the invisible hand; clearly.
  25. May 22, 2017 #150
    But often not in the right direction.
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