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> And that is why it is a huge problem for the power companies It is a problem, but not necessarily in the way you may be thinking. Peak residential power usag
by coryfklein 10y ago
> And that is why it is a huge problem for the power companies
It is a problem, but not necessarily in the way you may be thinking. Peak residential power usage is in the evening when solar isn't available. Power companies therefore end up spinning down coal and natural gas during peak solar, then just spinning them back up again as the sun begins to set. [1]
So you haven't replaced the coal and natural gas plants, you're just running them less. This results in higher overall costs, because you pay $$$ to build huge plants then just let them sit most of the day, which results in higher per-watt cost of non-solar power because the infrastructure and maintenance is no longer amortized over whole-day usage.
[1] My friend, a manager of 30 years at a huge mid-west power company
- adamweld 10y agoWhich is exactly why Tesla and other companies are investing in residential power banks. They have the potential for huge efficiency gains across the grid.
- epistasis 10y agoBeing a manager at a large power company for 30 years is both an advantage and a disadvantage. For the past 30 years, the energy industry has changed incredibly slowly, so ones expectations of what is possible in the way of innovation is far far lower than it should be. The "duck curve" that your friend is referring to will be solved in a variety of ways, from wind to storage to HVDC interconnects to the rest of the nation, to peaker plants. In the future, coal is dead. No need to build any more of it. Nuclear is too expensive to build anymore. (Unless somebody actually does thorium innovation, but I'm not holding my breath...) When storing a kWh costs $0.10, and there's also adaptive pricing to match supply and demand better, these problems will melt away. It does require a huge mental shift, but the cost savings will make that happen
- jobu 10y ago> When storing a kWh costs $0.10, and there's also adaptive pricing to match supply and demand better, these problems will melt away. If the math and assumptions in this article are correct, then that's exactly the (wholesale) price point Tesla is aiming for with the Powerwall: http://cleantechnica.com/2015/05/09/tesla-powerwall-powerblocks-per-kwh-lifetime-prices-vs-aquion-energy-eos-energy-imergy/ http://cleantechnica.com/2015/05/09/tesla-powerwall-powerblo... There are a couple other (not yet released) energy storage solutions mentioned there that might get the cost down even lower - Eos Aurora and Imergy Flow Battery
- ssmoot 10y agoIt'd take over 1 BILLION Powerwalls to store half the daily usage in the US (using old usage numbers off Wikipedia). I wonder if there's enough raw materials to make that realistic. And how to you manage recycling, repair, replacement, end-of-life concerns for all those batteries on that scale? Not asking a sarcastic hypothetical. Genuinely curious. It's hard to wrap my head around numbers that big. For reference I used this: https://en.wikipedia.org/wiki/List_of_countries_by_electricity_consumption https://en.wikipedia.org/wiki/List_of_countries_by_electrici..., divided it by days, then the Powerwall's 6.4kwh capacity and then halved that number. 4,686,400,000,000 / 365 / 6.4 / 2 == 1,003,082,191.8 Powerwalls.
- epistasis 10y agoJust throwing around "BILLION" doesn't make it seem big, you need to compare it the unit size. A single gigafactory is going to produce 35 GWh in a year, which is about 5.3 million power walls a year. If their lifespan is 10 years, than we need to produce 1e9 power walls / 10 years = 100 million powerwalls/year to maintain that capacity. So we'd only need 20 gigafactories worth to do this. And with wind and proper grid interconnects we won't even really need much storage at all to keep the electricity going; the national weather is very very consistent. We will need enough lithium for our ~300 million cars and their batteries, which are probably going to be 50-100kWh each, which is far far more than storing half a days worth of electricity.
- toomuchtodo 10y agoWhat if we used tens of millions of electric vehicles on the road as grid storage? Tesla has already planned on it: https://i.imgur.com/oLBNeW4.png https://i.imgur.com/oLBNeW4.png | https://i.imgur.com/pectzXn.png https://i.imgur.com/pectzXn.png
- ssmoot 10y agoThat's over 3 Powerwalls every second. And I've got to think you're not going to see more than 75% original capacity in ten years as a best case? I'm not as concerned about the factory as the supply chain, can we actually supply that much raw material, and what will mining it do to the environment? I assume lithium is much rarer than iron or copper. But I don't really know. For reference 16 million vehicles were sold in the US in 2013, but many (most?) of those were trucks and large SUVs, which AFAIK aren't on the roadmap for any EV manufacturer right now. And then there's fleet/work vehicles, single car families in states without long distance transportation or quick chargers (like TX). It makes me wonder if 20 years from now fuel cells won't completely obsolete batteries?
- coryfklein 10y ago> Being a manager at a large power company for 30 years is both an advantage and a disadvantage. He is definitely biased against solar, but is acutely aware of the costs it presents to traditional power generation and definitely well qualified to comment on them.
- epistasis 10y agoRight, and my point is kind of that the entrenched energy interests have been wrong time and again about solar, wind, and now storage. As well as HVDC. They don't understand these things, they see less than half of the equation because they don't want things to change, and they only see the problems and have no interest in solving them. IT wasn't that long ago that they were saying that solar was impossible, or that wind would never be affordable. They were wrong about that and they will be wrong about how difficult it is going to be to adapt to lots of intermittant renewable energy powering the grid. They will complain vociferously, and they may be able to talk about some of the difficulties, but we can't trust their perspective on the big picture.
- jimmcslim 10y ago> In the future, coal is dead. What about coking coal, for the production of steel from iron ore?
- tdyen 10y agoI've heard the claim it's indespensible but that's not true from a chemical point of view. But possibly from an economic point of view.
- eru 10y agoNuclear could be made cheaper (even with Uranium) by updating regulations. Fission plants are held to a much higher standards of safety in terms of eg decrease in quality adjusted life-years per Gigawatthour than any other form of producing electricity. Even solar. (Though most deaths and injuries from solar come from people slipping off their roof when installing residential capacity. If memory serves right.)
- kazagistar 10y agoThe problem is they have a huge spinup and spindown cost. So as long as we have solar, we need power that we can use at those times when solar is unavailable.
- Spooky23 10y agoA nuclear plant today would cost something like $6B that's not a regulatory tweak. The problem with nuclear is waste disposal (still not figured out, and a will be a problem for decades/centuries after the plant is closed) and amortization of billions of capital costs. With the price disruption potential of other technology, it's a bad bet, and has been so for many years.
- jessaustin 10y agoNuclear was only ever "viable" for political reasons. We had to have enough nuclear weapons to extinguish mammalian life nineteen times over. Eighteen times would have been pathetic. It was all a boondoggle anyway, so the war pigs were happy to spread a bit of cash on the civilian side...
- pyre 10y agoThere are nuclear plants that generate isotopes for medical purposes.
- jessaustin 10y agoThose are not the same plants that generate power for the grid.
- noir_lord 10y ago> Peak residential power usage is in the evening when solar isn't available. Assuming it's not a battery backed system, prices on those are dropping (or more correctly remaining stable while capacity slowly climbs).
- randyrand 10y agoDropping, but still incredibly expensive compared to the alternatives =( ~doubles the cost of solar.
- S_A_P 10y agoCan validate. The problem with electricity is that there is no large scale storage like there is for other forms of energy like NG and Crude. Until someone comes along and figures out how to store electricity, this will continue to cause grief to power companies. Power plants are really just options, if the price per kWh is at a certain point then it makes sense to spin up or take down a plant and generate power. Adding a bunch of highly variant generation to the grid can make the market more volatile since there could be a lot of up and down with generation facilities.[0] That said, there will be teething pains but this is a net positive thing that is happening. Growing up I lumped solar into the perpetual 10 years away category. It looks like I am going to see solar be competitive after all. [0] I implement trading and risk management software in the energy sector, including Crude, NGL, NG, and electic.
- amenghra 10y agoSome countries store energy by pumping water up a dam. Seems efficient.
- coryfklein 10y agoWhoa! That sounds really cool so I looked it up. It's called "Pumped-storage hydroelectricity" https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricit...
- inovica 10y agoVery. One of the first was in Scotland. Great to visit as you drive into the mountain and I think one of the Bond files had a scene filmed in it https://en.wikipedia.org/wiki/Cruachan_Power_Station https://en.wikipedia.org/wiki/Cruachan_Power_Station
- jackcosgrove 10y agoI would propose a global power grid as a solution to this problem, on which the sun would never set. The only problem is that earth is not set up well for this: the Sahara would be the solar workhorse of the planet, and the consumer of all this power would be Hawaii.
- walrus01 10y agoThe major challenge now is no longer PV and gridtie inverters, but energy storage. Whether it's batteries, pumped storage hydroelectric, whatever. $$$ per kWh stored (and the lifetime/cycle life + operating costs of that storage) is a key benchmark.
- puranjay 10y agoWait 5 more years and batteries will become cheap enough to even remove that constraint
- manishsharan 10y agoI am clearly out of my depth here but what if we take the newly daytime unused/idle coal power or natural gas power for other endeavors like sea water desalination or just pumping up water into a watertower when daytime energy cost is low and adding increased hydro capacity in the evening when the energy cost is higher?
- lancewiggs 10y agoThose sources of power have a higher marginal cost and are only spun up when the spot price is high enough - in peak demand times.
- eru 10y agoWhat you are talking about is demand shaping. It's already happening, but I predict we'll see more of that in the future. Eg lots of industrial applications like smelting aluminium can do with short-ish power cuts. In return, they get a steep rebate on their electricity bill.
- daveheq 10y agoThe power companies can get overflow from solar and wind and water and redistribute it at a profit while paying the residential over suppliers. It's on the power companies to build the infrastructure like batteries to take advantage of all this free new power.
- deleted 10y ago[deleted]
- g8oz 10y ago"Lets not move forward until every conceivable issue is solved" - said every entrenched interest ever.
- serge2k 10y agoThis is why we need a major leap in battery tech to make solar more viable. Plus there is the problems of cities with not enough sunshine and otherwise problematic weather (snow on the panels).
- Spooky23 10y agoThat's a good thing. Peak power usage is midday, so providing additional supply at that time avoids the need to site new plants, which costs millions or billions of dollars. It also makes coal less economical and makes gas plants, which are cleaner and safer to operate more economical.
- qwtel 10y agoSorry for the noob question, but isn't there always sun somewhere on the planet? Are electricity grids not globally connected, or would it be lost in transmission?
- daurnimator 10y agoThey are not globally connected. And losses become significant after a thousand kms or so. You're not going to get to the electricity to the other side of the world where the sun is shining. You need local storage. As much as is said about batteries, the only real solution here is hydro. Expect to see every viable valley start to get dammed over the next decade or so.
- ghaff 10y ago>Expect to see every viable valley start to get dammed over the next decade or so. Except that dams are instead being removed for a variety of environmental and associated reasons. Free lunches are rare. http://www.csmonitor.com/Environment/2014/0803/Setting-rivers-free-As-dams-are-torn-down-nature-is-quickly-recovering http://www.csmonitor.com/Environment/2014/0803/Setting-river...
- tedsanders 10y agoThis claim about peak power usage is untrue, at least for California. For the past 20 years in California, the annual peak electricity usage has ALWAYS occurred between 2pm and 5pm.: https://www.caiso.com/Documents/CaliforniaISOPeakLoadHistory.pdf https://www.caiso.com/Documents/CaliforniaISOPeakLoadHistory... I used to work at a power company as well. (It's true that the daily peak is in the evening and that won't be helped by solar. But capacity is built to handle the annual peak, not the daily peak, and because the annual peak tends to be hot afternoons, solar actually will replace other generation in the long run.)
- jfoutz 10y agoWell, you could just massively overproduce solar, and use the excess to pump water up a hill. Also, I think there are certain externalities with coal that your friend never had to pay for, like Mercury poisoning. Reducing the amount of time coal plants run may be beneficial to reduce those externalities.
- WalterBright 10y agoThere is another way - minute by minute pricing. Much of the electric power usage is not required to be right now, and can be deferred - running the refrigerator, A/C, hotwater heater, dishwasher, charging the car, etc. With real time spot pricing information available, the deferrable usages can be deferred until the spot price is cheap. I bet this could even out demand quite a bit. With the current flat rate pricing structure, there is no incentive whatsoever to shift demand to blunt spikes.
- RutZap 10y ago> Peak residential power usage is in the evening when solar isn't available. Power companies therefore end up spinning down coal and natural gas during peak solar, then just spinning them back up again as the sun begins to set. Would it be possible (in an utopian world) to actually have a global power network and route electricity produced during the day in one area across multiple timezones to an area where the demand is greater and no available solar? e.g. Electricity produced in West Africa at noon to be delivered to .. Tokyo, where it would be 9PM. I understand that politically this is almost impossible, but I am curious whether there are any technological impediments for this to be feasible.