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The future of solar power

  1. Sep 14, 2017 #621


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    Yes, this. Today Germany has 49 GW of coal fleet capacity. In 2002, Germany had ... 49 GW of coal capacity. Gas fired electric increased 50% over the same period. Germany runs the fossil fleet at a bit lower rate than it did 15 years ago, but that doesn't reduce cost much as you indicated.
  2. Sep 14, 2017 #622
    No one is violating the laws of physics, It would take roughly 50 Mwh of electricity to store the 35 Mwh of energy in a gallon of gasoline,
    but the processes are working, the Navy has received patents,
    Sunfire's system is producing fuels.
    The hard work is done, the scale up engineering is still ahead, but is possible.
    We already know that grid tied solar under the current conditions starts slowing down at about 8%,
    so we change the conditions by adding hydrocarbon storage.
  3. Sep 14, 2017 #623
    I didn't mean to imply (and did not say) that the linked process violated the laws of physics, it clearly doesn't. I mentioned that as a means to estimate the "best case" limits of any proposed solution.

    Regarding Sunfire, it seems to be as said earlier, a military solution where cost is not near the top of the priority list. From your link:

    Nowhere in there did I see any reference to this fuel being anywhere near cost-competitive with fossil fuels. So it simply is not reasonable to assume this process would be applicable to large scale use of any excess grid energy.

    I would be very interested if you could find a reputable source that shows a process like this has the potential to convert solar energy to gasoline to power my car, at a competitive $/gallon retail price, with all costs factored in.

    And their plans (as of a year ago), called for scaling this up to.... one gallon a day. So this is still very small scale demonstration level. The question is cost. We have plenty of storage options today, if you ignore cost.

    Please don't make me laugh, this is a serious subject. I will assume you have never brought a product from prototype to commercialization. I have, and trust me, there is still plenty of "hard work" to be done after your proof-of-concept has been shown to work in the lab. Often, it is the commercialization that is the hardest part, and often where the failures occur.

    Even Edison said it: "Invention is 1% inspiration, and 99% perspiration".
  4. Sep 14, 2017 #624


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    I found the following analysis interesting:

    NREL Report Shows Utility-Scale Solar PV System Cost Fell Nearly 30% Last Year
    September 12, 2017
    ...The report shows that the levelized cost of electricity (LCOE) benchmarks without subsidies for the first quarter of 2017 fell to between 12.9 and 16.7 cents per kilowatt-hour (kWh) for residential systems, 9.2-12.0 cents a kWh for commercial systems, 5.0-6.6 cents a kWh for utility-scale fixed-tilt systems, and 4.4-6.1 cents a kWh for utility-scale one-axis tracking systems.

    So all but the residential systems are generating power at less than what I pay for electricity. (12.2¢/kwh)

    And the breakdown of residential costs are really interesting.
    A visual snippet from the full technical report:

    Residential cost breakdown​

    As a lifelong, pauperish DIYer, the "Soft Costs*" kind of irk me.

    *Soft Costs
    Net Profit
    Overhead (General & Admin.)
    Sales & Marketing (Customer acquisition)
    Permitting, Inspection, Interconnection (PII)
    Sales Tax
    Install labor​

    I suppose though, if I had cash to spare, and was not a DIYer, then I'd not be irked, as, well, that's just how things work.
  5. Sep 14, 2017 #625


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    I really like this "Mark Jacobson" fellow.

    AAAS posted this a couple of days ago:

    September 12, 2017

    How practical is a worldwide switch to 100% renewable energy?

    BOB HIRSHON (host):
    Practical renewables. I’m Bob Hirshon and this is Science Update.

    Ask someone about making the world run on 100% renewable wind, water and solar energy, and they might say “can’t happen; just doesn’t add up.” But in the journal Joule, Stanford climate scientist Mark Jacobson and his colleagues report that most countries could convert to 100% renewable energy by the year 2050 and actually save money.

    I posted some thoughts on Facebook the other day, regarding his (Jacobson's) naysayers:

    Note to self; "Stanford professor Mark Jacobson is being negatively targeted by sciencey people for this idea, as it will put A LOT of sciencey people out of work." #DisruptiveInnovation #WithoutHotAir

    Note to self; "Look into background of all people denigrating Professor Jacobson's idea. Guessing they all have a financial interest in seeing his idea fail."

  6. Sep 14, 2017 #626
    Very interesting, and encouraging to see prices dropping.

    However, relative to the recent discussion of the ~ 8% limit we see for solar on grids, these costs go out the window at that point. If your grid presently is on the edge of excess solar on 4 out of 5 days, an added panel will only be able to sell 80% of what it produces, making the effective payback for that panel 25% longer, or requiring 25% more panels for the same revenue stream.

    I'm not a fan of that thinking. While it is a consideration, I like to see the facts and numbers speak for themselves, regardless who's mouth they come from. Facts and numbers represent science, pre-judging something based on who said it is a logical fallacy. Sometimes, someone who I dislike says something I learn from. If I discounted the source, I'd be the worse off for it.
  7. Sep 14, 2017 #627


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    Not if you have appliances that merge old school with new school technology.
    I'm fascinated by the non-chemical batteries of old, and how new tech makes them even better.
    I admit, that these devices don't yet exist. But it's only a matter of time, before they do.
    This is why I was so upset that Zooby couldn't sell his energy to me, when I needed it. The US grid should be totally integrated.
    I don't know who his detractors are, so I don't understand your logic.
  8. Sep 14, 2017 #628


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    You keep repeating this over and over again without responding to the points people are making about its irrelevance. Let me reformulate @NTL2009 's point with an example: we figured out the physics behind space travel 50 years ago and used it to put men on the moon. After that, "the scale up engineering" to build a colony on the moon "is possible". So why hasn't it happened? Because the laws of physics still dictate how big of a rocket it takes to get to the moon, which thereby dictates how much it costs. So a colony won't happen without a game-changer technology because the laws of physics drive the economics and prevent the idea from being affordable.

    Closer to home, the laws of physics dictate the size and height of reservoir needed, size of piping, size and power of pumps/turbines, etc required for a certain amount of storage, which therefore dictates the cost. That's why pumped-storage is a difficult proposition.

    You're completely ignoring this issue with the technology you are discussing (not necessarily your fault: it is generally glossed-over in the media hype of new inventions), but it is certainly there and it is unlikely to allow the technology to become viable.
    It may "make sense" but the reason it hasn't happened yet in a scale needed to save solar is because it costs more money than it saves. I doubt the solar-to-gas idea will fix that.

    The choice is essentially this for places that haven't maxed-out their solar without storage:
    Option 1. [do nothing] Keep an existing gas/coal plant (zero capital cost, a certain production cost).
    Option 2. Build a solar plant. Keep the existing coal/gas plant for back-up at a higher cost than it was before.

    Right now, Option 2 isn't too painful, so people are doing it some.

    For Germany and several other countries, Option 2 doesn't really work anymore because above 8% some of the output of a solar plant gets wasted if there is no storage. So now we have:

    Option 3: Build a solar plant. Keep the existing coal/gas plant for back-up at a higher cost than it was before. Build a storage or conversion plant.

    Since Option 3 incorporates Option 2, it *must* be more expensive than Option 2.
    Last edited: Sep 14, 2017
  9. Sep 14, 2017 #629


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    Installing solar to <10% limit suggested by the data is i) expensive and ii) not remotely good enough as an end point to avoid the possibly severe warming scenarios from emissions. The <10% limit required 10-15 years in those countries. By contrast, France used nuclear to go from 60% fossil to under 10% in 12 years.

    The countries that are least able to subsidize solar or wind have been installing coal instead. India is now the world's 2nd largest consumer of coal and growing fast. Other countries are chasing them to the top of coal heap, Indonesia, Vietnam, Turkey.

    Wind does tend towards more output at night, but it also nonetheless goes to zero occasionally, meaning the entire conventional fleet must be maintained; again, an expense many countries will not tolerate.

    Demand shift does not have zero cost, but is quite expensive. Many utilities have programs in place, have had for decades, with peak load seldom moved more than ~5% or so. See for example aluminum production, which has notoriously high electricity consumption. If these plants loose power for many hours, they freeze up, requiring expensive restarts.

    Nobody wants HV transmission through their backyard, and it too is expensive.

    Battery storage at utility scale is an order of magnitude two short, both in production and cost. While utilities have for years used batteries to aid in momentary transients, there is no battery storage project in the world that could back up a middling 500 MW solar or wind farm for a day, much less the seasonal outages, nor are there any serious plans (ie financed) to build one.
    Last edited: Sep 14, 2017
  10. Sep 14, 2017 #630


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    About 3/4 of that residential rate charged by your utility is for the grid itself (transmission and many generating plants) and your connection to it, available 24/7. The cost for the utility to actually flip a switch and generate electricity through that grid from one of it's many sources is 1 to 5¢ per kwh, 95% of the time. Cutting loose of the grid and going it alone with some solar and a combustion generator behind the curtain has a far higher cost than the residential rate charged by the utility.

    As for off grid solar and batteries, it's done for the like of part time cabins and boats, but I'm unaware of any examples of full time, full size, off grid residences in the US by means of solar and batteries. Even long time 100% renewable power advocate Amory Lovins has a grid connection to his mountain home.
    Last edited: Sep 14, 2017
  11. Sep 14, 2017 #631


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    You're not comparing their generation cost to your total cost, are you?
  12. Sep 14, 2017 #632
    Re: Trillion Dollars of windmills/solar = Middle East:

    I can't find my original sources So I have to redo this calculation. I did the conversion based on how many watt/hours were in a barrel of oil, and what was the realistic long term output of a windmill.

    An important factor in this is that we don't get that much of our oil from the Middle East, so replaceing it with windmills still leaves us with plenty of oil for 747s. We are going to see a big upswing in electric cars in the next few years, as they will soon be cheaper then gas. They tend to charge at night, thus evening out demand spikes.

    Remember that cars get replaced regularly, so the cost of switching to electric is only ADDED cost of the new car that you were going to buy anyway. People who actually need to drive cross country already know not to buy electric yet, there is no need for you to make that decision for anyone else.
  13. Sep 14, 2017 #633

    I don't think that is a factor at all. Commodity products are fungible. In order to say we aren't importing any oil from the ME, we need to not import any oil (at all). Our demand for imported oil will be filled from world supplies. You can't segregate ME oil any more than you can segregate solar or wind driven electrons on the grid (I want those electrons!).

    OK, we can assume some % of EV adoption, but let's not overdo it. Not everyone has access to chargers, and range will be an issue for some people, and long haul trucks, trains, etc (not just 747's) will be petroleum based for the foreseeable future.
  14. Sep 14, 2017 #634
    The original quote was "One trillion in windmills and solar cells would generate more power then we get from the middle east." It doesn't NEED to be different oil or electrons. The point was to eliminate US dependence on the middle east so that radicals 1. Can't keep blaming the US for their problems, and 2) Have less money to fund terrorist activities.

    If you live in a cave with no electricity, then EVs are not for you. Got it.
  15. Sep 14, 2017 #635
    Something makes me think that they will blame us even more, if we were to effectively boycott their products - that usually makes the provider mad at you. And again, oil is fungible, others will buy from them. Unless we eliminate all our oil imports, a % will continue to be ME oil. Like I said, I'm not sure it is even meaningful to assign the entire cost of our ME involvement to oil, but if you are, we need to at least isolate ourselves from all imported oil.

    Now you are being silly about a serious subject. I lived in the city of Chicago for some years. That is a large city, not a cave. Many people are in apartments, with no electricity at their parking space, many people park on the street. Of homes with garages, many/most are detached, and out in the "alley", and are wired for a single 115 V 15 A circuit (maybe less - they were electrified a long time ago when all anyone wanted was a single 60W light bulb - luxury!).
  16. Sep 14, 2017 #636


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    The large majority of the world's vehicle owners don't have two car garages. They increasingly live here:
  17. Sep 14, 2017 #637
    Solution: costs $239


    Also if you park on the street, you probably aren't buying a 2018 model car for a few years. If the city can install street lamps, they can install outlets. And the latter will make them some money so there will be plenty of motivation to do so. I live in the suburbs and all the malls near my house have electric charging stations already.
  18. Sep 14, 2017 #638


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    Street lamps are typically 400 W, one or two per block, not 6000 W per parking space.
  19. Sep 14, 2017 #639
    So we are going to fight another gulf war because it's easier than installing a $239 cable? You guys seem really desperate to find obstructions here.

    Yes, they'll be mad at us, but what will they do, refuse to sell us oil? Reduced demand will make the price go down for everyone, and if they reduce supply they reduce their profits even more. And it's not like we'd be on our own doing this, Europe is already ahead of us. Or the rich oil sheiks will realize that terrorism is hurting their profits, and they will get serious about stopping it.
  20. Sep 14, 2017 #640
    Your cable "solution" is about as viable as all the other "solutions" that have been provided.

    A semi truck won't get very far on a 100 foot cable.

    Imagine all these EVs, charging at night (so as not to cripple the grid during daytime heavy loads). No solar w/o storage, still need fossil/nukes for low wind nights. Not as simple as a silly cable.

    Solar has a place, but it's limited. Best to understand and work within those limitations than to count on unicorns to show up.
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