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The true price of solar is the price to produce reliable, continuous energy. That requires something to smooth out the signal and store the energy, most probabl

• immad 8y ago
  Why can't existing energy infrastructure handle the gaps? Does it take too long to boot up a natural gas plant just for the night? Would still make a huge dent to energy needs and the existing infrastructure already in place.
  • rock_hard 8y ago
    Without a buffer (like a battery) solar energy fluctuates highly because of clouds and other things that get in the way for split seconds during the day.
    • rtkwe 8y ago
      That seems like a point where distributed rooftop solar has a pretty good edge over utility solar (ie huge fields of solar cells). Spread over a large enough area all those tiny peaks and fluctuations will even out largely.
  • inputcoffee 8y ago
    That is true, and existing infrastructure does (mostly) handle the gaps. How much does "existing infrastructure" charge to handle the gaps? This calculation differs wildly from as low as $6 to as high as $15, but I think $12 is the right answer. So add $12 to solar only as a rough rule of thumb. Note that this $12 still comes with transmission issues, and environmental impact.
  • rsynnott 8y ago
    That's what's generally happening. It's a bit of a limiting factor, though. As you have more and more renewable, you need more and more gas plants which mostly sit around doing nothing, which isn't free. There's also the opposite problem, particularly in the case of wind turbines; if you have enough, then your base-load (ie coal, nuclear, hydro) plus renewable may sometimes exceed demand. This happens from time to time in Ireland, for instance, due to a large installed base of wind. At that point you have to turn off renewable, and that's not always trivial or instant. Storage would help there, too, by absorbing the excess.
    • ghouse 8y ago
      > As you have more and more renewable, you need more and more gas plants This is only true if the load on the grid is growing. In North America, it is not. Otherwise, you already have enough dispatchable generation available when the sun isn't shining or the wind isn't blowing.
      • rsynnott 8y ago
        This is assuming that you're replacing old, bad power (ie coal, or old-fashioned unresponsive gas plants) with a solar/responsive gas turbine combo. The US still has a fair bit of coal that could stand to be replaced, but I doubt there's enough gas to take up the slack of a solar/gas system without building more.
        • ghouse 8y ago
          Over the past decade (since the wide-scale commercialization of fracking in the US), coal plants have been retired or repowered (with gas) at a record pace. I believe the share of generation has dropped from 50% to 30% in that period.
      • p1mrx 8y ago
        The North American grids will need to start growing again, if electric vehicles become common.
      • 8y ago
  • coryfklein 8y ago
    Because total load on the power grid peaks at 8 PM when solar is providing nearly 0% of the power [1]. This means that no matter how many additional solar panels you add to the system, you are not displacing a single fossil fuel plant. Sure it's good that those plants are running nominally fewer hours per day per additional solar panel, but the cost to own, operate, and maintain the panels is roughly constant. This results in the effect of increased prices for fossil power in a way that can't be offset by solar. [1] https://en.wikipedia.org/wiki/Duck_curve https://en.wikipedia.org/wiki/Duck_curve
    • stale2002 8y ago
      Industrial usage makes up a large percentage of total energy usage. Industrial energy usage can be time shifted. Who cares about residential power, if it is a small percentage of total energy usage?
• babaganoosh89 8y ago
  Also the cost of installation. At least for home solar, installation makes up the majority of the cost.
  • inputcoffee 8y ago
    Yes, and any estimate of solar only costs is composed largely of financing charges which is another way of saying capital costs. These include the installation.
  • mrfusion 8y ago
    I have an idea for a product to solve this if anyone is interested in chatting. I just don’t have the capital or hardware knowledge to get it going.
    • neworbit 8y ago
      Your username suggests an option, but I shall hope you are focused on solar at the moment
      • deleted 8y ago
        [deleted]
      • willismichael 8y ago
        Solar is fusion, right?
      • mrfusion 8y ago
        Just solar but rethinking things into something you can start using without installing.
        • Kliment 8y ago
          There's a local cooperative here in Germany (named Energiegewinner if you want to look them up) that acts as a facilitator for this. They're approaching this from all directions: 1. You can buy power from them at normal power company retail rates. You get power from the grid that they buy at wholesale rates, profits go into building out solar. 2. You can become a member by buying any number of shares. Capital gets used to fund solar buildout, profits go back to each shareholder. Each shareholder has one vote regardless of the number of shares they own to prevent buyouts. 3. You can rent them your roof space. You get paid, other people put cells on. You get reduced-rate power from your own roof's cells, excess goes to grid. 4. You can buy solar panels and rent them to the cooperative. For every large installation they make, they'll ask people to buy panels. You get paid a part of what the panels produce for 20 years, at a guaranteed rate, and at market rate after that. 5. You can have them act as a solar installer and set up panels on your property for your own use. They'll buy excess production and sell you grid power when you have insufficient production. In this case you finance the install yourself. They have excellent economies of scale from standardizing installs and they allow people with capital but no roof space to connect with people with no capital but usable roof space. Because retail rates for power are high and they've centralized installation costs they're making an okay profit. Maybe something like this can work where you are?
• rsynnott 8y ago
  I wouldn't bet on batteries, or at least conventional batteries, being the long term solution. There's interesting work being done with air pressure storage, flow batteries (the largest batteries currently under construction are mostly flow batteries in the 500MWh-1GWh range, though the technology is still in its infancy), and big scary vacuum flywheels. All of these are far less developed than lithium ion cells, but have the potential to do a lot better on cost and longevity grounds.
  • CompelTechnic 8y ago
    One weird thought I had the other day: high voltage DC transmission lines are getting more popular. I wonder if it would be economical for a high voltage DC line to form a loop around the entire planet, so that the load can follow the sun through a complete cycle.
    • rsynnott 8y ago
      This has terrifying geopolitical implications, so probably no-one will want to depend on it anytime soon.
      • matt4077 8y ago
        It's no different than data links, which have mostly worked without political interference.
        • sokoloff 8y ago
          In general, your data does not have value to me to steal it. Not so with power.
          • Kliment 8y ago
            Data has plenty of value, and is often copied without authorization, but putting that aside, nobody would be stealing anyone's power. It gets produced in one region, used locally, and excess sold to the next region, where the same thing repeats. You already paid for the power entering your region so you can't steal it and you'll sell it on if it makes sense to do so. This is already how gas pipelines work for example. It's shit with gas because the flow is one way and shutting off the gas is often done for political reasons but with solar you'd have your own production ramping up a few hours later if the neighboring region either shuts it off or uses a higher percentage of what they produced. Either way the metering happens at regional boundaries so there's no stealing involved - both sides of the meter need to be in agreement before any power flows.
• raldi 8y ago
  How do you track it? What is it now?
• ghouse 8y ago
  False equivalence. A similar argument could be made of nuclear power (which needs to run at/near 100% output), or supercritical coal (similar operating constraint to nuclear). Do we need to add batteries to those as well to make an apples-apples comparison? (Incidentally, much of the pumped hydro in the US was built to integrate nuclear power). Unless you're trying to power the grid with a single power plant (like on a small island), argument made above doesn't hold. The grid is a network of generators (and loads) with different operating characteristics.
  • reaperducer 8y ago
    Plus, just because the sun goes down doesn't mean all solar generating stations stop making electricity. I'm not even remotely an expert in this field, but the towers at the solar furnaces I've seen continue to glow well into the night, meaning they're hot enough to still generate steam, and thus electricity, long after it's dark. I don't expect they generate electricity all night, but maybe not as much energy needs to be stored as people assume.
    • abfan1127 8y ago
      the solar furnaces take time to heat up in the morning too, so its more of a skew of time, rather than a stretch of operating time, although depending on the efficiency, it may stretch too.
    • CyberDildonics 8y ago
      Not only that, but solar generated in one place can supply electricity to areas where the sun has not hit yet, and likewise after the sun goes down, those same places can draw power from further west.
      • aalleavitch 8y ago
        I like the idea of having essentially a grid “wave”: in the morning your power comes from the East, in the evening it comes from the West.
• jartelt 8y ago
  This comment gets made in every single solar article put on HN. The true price of solar is what the market is willing to pay for it. If the solar was ruining the grid or was way more expensive than what it seems, we would not keep seeing solar installed at this pace and at these costs. We need to get out of the mindset that all power generators need to produce a steady amount of power 24/7. A flexible grid made of many power sources that can be ramped up and down can just as easily meet demand and may even be best since it is resilient when any one power source goes down for an extended period of time. You can't just say that solar should be more expensive because it only works half the day. You could just as easily turn that argument around and say that nuclear and coal plants should be more expensive since they are only economical if run at a constant load and require long shutdowns every year for maintenance. There needs to be extra capacity on the grid to meet demand during nuclear/coal shutdowns, but no one states that nuclear and coal should be more expensive as a result.
  • inputcoffee 8y ago
    You misunderstand the sense of "true" here. The point is not that the "true" price in the sense of what it ought to be. It is the "true" price in the sense of what the market is actually paying for the service. When people put out the number $23, they compare it with the cost of power and wonder why, if it is so much lower, it doesn't already swamp the current solution. So the purpose of the comment is to explain that it is not a complete solution, and not reflective of the total ("true") bill.
    • matt4077 8y ago
      Yet the market isn't "actually paying" for battery storage at anywhere near the amount of installed solar capacity... Which was the point you misunderstood: dedicated storage installation are not needed at current production levels, and can be avoided even when solar's share of the energy mix grows. Among the possibilities are "smart" appliances scheduling their demand to production peaks (dishwashers can often wait a few hours, cars might not need to charge right away). The same is true for industrial usage, where smelters, for example, have the natural capacity to store energy as heat. A growing fleet of electric cars could also serve as distributed storage: if your car is parked for the night, it could feed energy back into the grid (partially, if you are paranoid).
• Florin_Andrei 8y ago
  There's a lot of "lumpy" demand that peaks during the day, requiring no storage. E.g. all air conditioning would be perfect as a consumer of solar energy.
• mikec3010 8y ago
  > reliable, continuous energy. That's the job of the inverter, right? It uses free solar energy first and maintains reliability by supplementing it with costly grid power.
• Animats 8y ago
  Not entirely. About 10GW of solar capacity would cover the entire air conditioning load peak for California[1] That's when power prices are the highest, and it doesn't need energy storage. Pretty soon, most air conditioning load will be on solar power. [1] http://www.caiso.com/TodaysOutlook/Pages/default.aspx http://www.caiso.com/TodaysOutlook/Pages/default.aspx
  • rwcarlsen 8y ago
    But you do need storage and/or backup providers because not having air-conditioning run on cloudy days is not an option.
    • CyberDildonics 8y ago
      You realize the electrical grid means that excess power can go to other states right?
    • dragontamer 8y ago
      Cloudy days are usually cooler, and you still generate solar power on those days. True, you still need an alternative source of energy in those cases. But realistically, cloudy days reduces the sun, which usually leads to lower temperatures. --------------- Personally, I think that cold-energy storage (aka: run air-conditioners on overdrive to chill water. Then use chilled-water to cool your house) is the ideal. https://www.ice-energy.com/ https://www.ice-energy.com/ It turns out that a vat of 480 Gallons of cold-water has a lot of cooling potential. Chill the water to 40F and you can cool down homes for hours using fans alone. With proper compressors and such, you are like 95%+ efficient. Your failure mechanism is the probability that your vat of water begins to leak its cold air. Certainly a problem, but way simpler and less of a problem than explosive Li-Ion batteries.
      • cgdcraig 8y ago
        Cold energy storage has always had the problem of utilization and capital cost. You need to buy the storage system and then that storage system may only be useful for 3-6 months of the year during 6 hours of the day. From a thermal efficiency perspective they're great but in general they get offed by the economics. For the price you'd end up gettinf better value off a battery storage system to do load shifting.
• cletus 8y ago
  To quote Dwight... "False." It is true that a wide electrical grid needs a base load. It is also true that solar isn't great at continuous power because of, you know, the Sun sometimes being behind the Earth. But that doesn't mean you need necessarily need batteries. There are at least two scenarios where you don't: 1. You have an alternative to batteries for storage. This could mean using excess solar power to create some fuel that may well also be portable. This isn't an economic way of creating gasoline (yet) but in remote places this might not matter. It also might not matter if this power is essentially "free" (eg you need to build a certain capacity anyway which leaves times where excess power is being generated). 2. Power usage on electrical grids is also not smooth. It also peaks during the day when, as it happens, the Sun is also out. So your solar capacity is actually reducing your peak grid power requirements, which is incredibly useful.
  • dragontamer 8y ago
    With regards to #2: You should study the "duck curve" and "nessie curve". In particular, in Solar-heavy situations, the peak energy is now 5pm. When the sun begins to set but there's still a large demand of electricity. Batteries in today's form cannot solve the duck curve. So the only reasonable situation is to use natural gas plants to supply the grid with power. Future batteries need to be built more efficiently and cheaper to deal with the many Gigawatts and Gigawatt-hours (both power AND energy capabilities need to grow) to deal with the future duck curve and/or nessie curves.
• dragontamer 8y ago
  No more than the true-price of Nuclear is the price to spin-up and spin-down nuclear as the electric grid demands. There's "baseload power" (coal, nuclear, wind, solar is really good for this), and there's "Peaker power" (natural gas and hydro are really good for this). Hydro is super-simple. Just block the water if you don't need energy, and unblock it when you need energy. Ditto with Natural Gas, which can spin up / spin down arbitrarily. Solar, Nuclear, and Wind generate power on their own schedule and can't really be bothered. But you use OTHER forms of energy when the sun stops shining. Natural gas is expensive to run 100% of the time. But if you can run Natural gas only 20% of the time, then you're still saving money.
• coryfklein 8y ago
  Agreed. Without some alternative form of energy in the morning and evening we may have already reached the saturation point of solar energy. See the Duck curve [1]. Once the heavily regulated energy market has time to adjust to market conditions you are going to see this energy surplus during the day being adjusted for. Where solar panels make economic sense today they may not tomorrow when energy prices for mid-day use plummet due to oversupply. [1] https://en.wikipedia.org/wiki/Duck_curve https://en.wikipedia.org/wiki/Duck_curve
  • raven105x 8y ago
    Prices will not plummet due to oversupply, they will increase as demand decreases to increase profitability. Electricity prices reflect only one thing: how high they can be while still being "affordable". Even now, in most major cities, residential pricing is 10x-50x of business/industrial pricing ...in the same zip code. The cost of production of electricity is almost enitely irrelevant to its' pricing.
    • maxerickson 8y ago
      What electric companies have rates like that? In the Midwest it is like a factor of 2 for energy, maybe (residential energy in urbanized areas around here is $0.10-$0.15 per kW-h, with a day charge of ~$0.50).
  • maxerickson 8y ago
    Thermal storage is super easy for cooling and can be used to shift the evening load. Just offer economic incentives to put ac on a timer.
  • Brakenshire 8y ago
    Energy prices plummeting in the middle of the day creates an enormous economic incentive for energy storage or demand shifting, which in turn makes energy in the middle of the day more valuable.
• woodandsteel 8y ago
  If you had actually read the article, you would have discovered that many of the projects covered in the Nevada auction included batteries.
• stale2002 8y ago
  There is an alternative. Don't "smooth" it out. Just provide double the capacity needed. If prices go low enough, you can solve the problem by just throwing more solar panels at it.
• nikdaheratik 8y ago
  From the article: “Three years ago you almost never saw batteries as part of a new solar or wind project,” Naam said. “In 2018, we’ve seen battery storage frequently show up as part of these bids. Energy storage is becoming the new normal with solar bids.” So they are already working on it with some of the projects at least, and there's no reason to think they won't scale up and start becoming competitive before too long.
• jrochkind1 8y ago
  So... did you read the article, mr. top-voted comment? > The Nevada auction also included a number of projects that link up utility-scale solar with batteries. Mastering solar plus storage will be critical for renewables to truly overtake fossil fuels, since they only generate power when it’s sunny or when the wind blows. > “Three years ago you almost never saw batteries as part of a new solar or wind project,” Naam said. “In 2018, we’ve seen battery storage frequently show up as part of these bids. Energy storage is becoming the new normal with solar bids.”