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Why Energy Storage Is About to Get Big – And Cheap

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Re: Why Energy Storage Is About to Get Big – And Cheap

#211

Post by URSpider94 »

mark-r wrote: post #77
URSpider94 wrote: post #69

One problem that will surface is that the cost of our transmission infrastructure will have to be covered, one way or the other. Currently, with net metering, customers are able to arbitrage power at the retail price, while effectively making use of the grid for both pushing and pulling load. This would be like flying a round-trip from San Jose to Tokyo and back to SFO, and claiming that you only owe the airline for…

All the more reason for local storage. The closer to the end user that the power is stored, the less load on the transmission lines. If you store it at your own house, it never needs to hit the grid at all.

Yes, that's a good thing. However, imagine a world in which everyone has local storage and only needs power on the 10 days of the year when it's dark and rainy. So, let's say the total power draw per household drops to 100 kW per year (about $15 at California power rates), vs perhaps 10,000 kW per year today (about $1500). Meanwhile, the cost for maintaining the infrastructure changes very little -- crews still need to come out and trim trees away from the lines, pull fried squirrels off of transformers, re-string lines after a storm, etc. Assuming half of your current bill is spent on infrastructure, the utilities would need to recoup $750 or so per year from their customers to provide that $15 in power.

Re: Why Energy Storage Is About to Get Big – And Cheap

#212

Post by eigenvector »

ghshephard wrote: post #151
eigenvector wrote: post #57

Earlier quoted context omitted.

Well yes, it's dispatchable in that sense. If you frame dispatchable as a binary property, it's certainly dispatchable in the way that wind is not. But if you think of it from a power system planning perspective of economic dispatch (not just, can I dispatch - but can I afford it), nuclear isn't really there. Yes, you can E-stop a nuclear plant in seconds, but the cost is astronomical. Some nuclear plants like Bruce…

My company does work in the UK, and we're putting together communications system that will allow the wind generations systems to stop loading the network when the transmission lines get too hot (apparently it's less expensive to shut down the wind power x% of the time, than it is to build new transmission lines). I'm wondering if you have any insight into what happens when our comms system sends a signal to those win…

The primary way that a wind turbine "stops" is by pitching its blades (in some vendors' terminology they call this "pause" because the machine is still connected to the grid just not producing any energy). On modern machines this can reliably be achieved in less than 3 seconds. There is also a mechanical brake that can be applied for emergency stop in 1 second or less. However, mechanical braking is not to be used in normal operations.

However, going to the maximum ramp-down rate (which for a large wind park can approach hundreds of MW/s) is usually not desirable because it will impact grid voltage. At most wind parks voltage control is accomplished using on-load tap changes of the main transformers as well as switched capacitors. Both of these need a time delay of at least 10 seconds to avoid wearing out quickly so if you ramp your whole wind farm from max output to zero in 1 or 2 seconds, you will see a big impact on grid voltage. So if we need to ramp down for a transmission system thermal constraint, we will do it at the slowest possible rate that still meets the transmission utility's needs.

Re: Why Energy Storage Is About to Get Big – And Cheap

#213

Post by eigenvector »

ghshephard wrote: post #168
Animats wrote: post #158

Earlier quoted context omitted.

Antenna towers get hit all the time, and the transmitters and receivers survive if installed properly. First, there's a spark gap between the antenna and ground, with big metal contacts, copper or silver, a short distance apart. That diverts most of the lightning bolt to ground. Then the feed line for the antenna has a big inductor, a coil made of heavy busbar, usually in a grounded can. This is often placed through…

You seem to know a lot about this, so all I can do is reiterate that when we take our electronics to florida to be tested, our QA guys make it clear that no company's electronics are designed to survive a lightning strike - including ours. (Though we are designed to resist a 22 calibre bullet). We install a lot of lightning arrestors, mandatory in Florida, São Paulo, Singapore -- and we seem to do fine in those areas…

I think you and GP are actually agreeing. The goal of a lightning protection system is to ensure that when a structure (antenna, wind turbine, transmission tower, etc.) is hit by lightning, the lightning energy is provided with a low impedance path to earth such that any sensitive equipment inside or attached to the structure is not exposed to currents and voltages beyond its design limits.

There are other considerations as well for personnel safety, like ensuring that the ensuing ground potential rise doesn't expose someone standing near the earthing point to a shock hazard.

Going back to the original comment, lightning protection in wind turbines is more or less a solved problem. Direct hits on blades are routine and any utility-class wind turbine will be designed with an appropriate system for the area in which it is located. Now, when your turbine is on a big rock, that's a problem and you may have to blast and backfill to achieve a sufficiently low earth resistance.

Re: Why Energy Storage Is About to Get Big – And Cheap

#214

Post by snowwrestler »

flgb wrote: post #177
DennisP wrote: post #110

Earlier quoted context omitted.

I wrote a couple pro-nuclear comments here. I'm perfectly happy with wind and solar and think we should roll it out as fast as we can, as well as nuclear. Many of the wind/solar advocates, on the other hand, are strongly anti-nuclear. Given the state of the climate that just doesn't make sense to me. All these technologies have their own advantages, and we should use each where it's most effective.

I think there are two separate dynamics here, and its worth keeping them separate. Firstly, there is the traditional concern of the green movement with nuclear waste and nuclear weapons proliferation. Nuclear advocates say these concerns are misplaced because of nuclear technology innovations (although its not clear how close the new technology is to wide deployment). Secondly, there is an economic and free-market co…

The only reason Aunty can put solar on her roof is because she has the centralized electrical grid to back her up. Put another way, if Aunty had to choose between roof solar and centralized grid (exclusive of one another), most Aunties will choose the grid because it is much more reliable.

That's how we ended up with centralized generation and a grid in the first place--the initial roll out of electricity was highly localized, with factories, buildings, and blocks each having their own generators. Centralized + grid beat that architecture on reliability and cost.

So, the grid needs to be available with or without solar. Thus the "free market" concern is less of a differentiator than it seems on the surface.

Re: Why Energy Storage Is About to Get Big – And Cheap

#215

Post by snowwrestler »

lotsofmangos wrote: post #154
beat wrote: post #135

Earlier quoted context omitted.

I'm neither pro- nor anti-nuclear. I'm not afraid of it and recognize that it has value (I really like the idea of using it for base load generation with wind/solar), but I also think it's a very limited solution, due to its expense, complexity, and political difficulties. If we can build a purely solar/wind/storage model that is inexpensive, safe, and uncontroversial, I'd much prefer that.

I am not anti-nuclear, I am just anti-nuclear (of the type that is useful for enriching for weapons) for the global solution to electrical power, given that for a general solution you need something that politically, you don't worry too much about your enemies having. Look at the situation with Iran for instance. Any development of nuclear there is viewed with extreme suspicion, even while we are trying to reduce glo…

Very few people oppose nuclear power for Iran on principle. Opposition to development so far has been based on the obvious evidence that in Iran, "nuclear power" has so far been a fig leaf for developing a nuclear weapon.

The framework that the U.S. is negotiating with Iran right now will allow them to continue nuclear activities that legitimately lead toward peaceful nuclear power.

Re: Why Energy Storage Is About to Get Big – And Cheap

#216

Post by snowwrestler »

fennecfoxen wrote: post #2

The other reason energy storage could get big in the next several years is an elevated risk of blackouts due to aggressive retirement of coal-fired power plants -- blackouts like the one in Washington last week that shut down several government agencies (e.g. the Department of Energy ) and which was probably related to the shutdown of the Potomac River Generating Station.

That plant stopped generating in 2012, so I'm not seeing the connection to last week's power outage.

Re: Why Energy Storage Is About to Get Big – And Cheap

#217

Post by flgb »

snowwrestler wrote: post #214
flgb wrote: post #177

Earlier quoted context omitted.

I think there are two separate dynamics here, and its worth keeping them separate. Firstly, there is the traditional concern of the green movement with nuclear waste and nuclear weapons proliferation. Nuclear advocates say these concerns are misplaced because of nuclear technology innovations (although its not clear how close the new technology is to wide deployment). Secondly, there is an economic and free-market co…

The only reason Aunty can put solar on her roof is because she has the centralized electrical grid to back her up. Put another way, if Aunty had to choose between roof solar and centralized grid (exclusive of one another), most Aunties will choose the grid because it is much more reliable. That's how we ended up with centralized generation and a grid in the first place--the initial roll out of electricity was highly…

This isn't about grid or no grid. We will have a grid for the foreseeable future.

This is a question about how distributed energy generation with battery storage shifts more and more loads to the edges of the grid, and onto private networks.

And then, relating to back to the question of whether nuclear is compatible with renewable energy, the question becomes how does this trend affect what technologies make the most sense?

Big expensive nuclear makes a lot of sense in an environment where all the loads are on are centrally managed and planned grid with either guaranteed rates of return, or steady wholesale electricity prices, but this is not what the future looks like.

Re: Why Energy Storage Is About to Get Big – And Cheap

#218

Post by Tsagadai »

greggyb wrote: post #67

If there's a legitimate arbitrage opportunity for individual homeowners to buy a battery and charge it overnight to cover peak costs, there should be an even stronger case for energy companies to buy larger batteries, install them in low-land-cost areas, and do the thing themselves. If these peak plants are so expensive, then a major utility can save money using batteries rather than peak plants. The cost should be l…

Some home owners are doing this. Charge the batteries with solar in the day and top up with offpeak if more is needed for the early morning (say if you are using electricity for heating in winter). Not entirely off the grid but minimizing costs. I have talked to one industrious hacker who has two battery installations. He charges one off offpeak and feeds it back in for a profit in peak times while charging the other on solar and doing the same thing (because providers cap the amount of current you can feed back into the system as an individual). I am looking at getting myself a solar + batteries + grid system so it doesn't seem so far fetched that investors may be planning something similar.

Re: Why Energy Storage Is About to Get Big – And Cheap

#219

Post by brownbat »

ulrikrasmussen wrote: post #163
brownbat wrote: post #109

Earlier quoted context omitted.

Except it takes a really big train to weigh as much as a lake. Pumped hydro is unbelievable. Tour a pumped hydro facility if you ever get the chance, and ask about the economics. They're buying a dollar of energy at night in Spring and selling it on hot summer days for something like five hundred. (Probably not quite that much, but it was a crazy ratio, to the point where efficiency barely matters - also, free energy…

The ARES website claims that the cost of their train technology is only 60% of an equivalent pumped hydro facility [1]. This is pretty impressive, and I wonder how they do that. Maybe because a water pump is not just a turbine operating in reverse, and thus pumped hydro needs separate equipment for charging/discharging, whereas ARES can use the same? [1] http://www.aresnorthamerica.com/santa-barbara-energy-storage...

Interesting.

From site: "3GW Regional Energy Storage Hubs. Energy capacity may range from 4 to 16 hours duration at full power output."

The 3GW is big but the duration is small, so I'd guess they're doing short term grid stabilization, competing more with flywheels than hydro. That's just a hunch, but if that were true, it'd explain how you could get something really effective without a lake-sized train. (Some videos online suggest they move a bunch of heavy cars on the same track independently, so they probably also get much more weight than a normal train.)

My limited understanding of pumped hydro specifically was that it really was basically just a turbine operating in two directions, crazy as that sounds. Even so though, I can easily imagine big cost savings just from not having to engineer around water. That stuff doesn't compress, you design or run these wrong and they'll just mercilessly explode: https://www.youtube.com/watch?v=6hVUeNp3o3M

Being able to build anywhere is really neat too.

So, grid storage tends to fracture into a half dozen specific types of storage, all based on duration, spin up time, geography, fuel, etc. There are like 18 different tradeoffs, and you can specialize in any one of them. Pretty much any new grid storage technology is going to add to the field rather than displacing anything, because the grid needs arbitrage in basically all 18 different dimensions.

Thanks for the link. There are some cool ARES videos on youtube too.

Re: Why Energy Storage Is About to Get Big – And Cheap

#220

Post by escape_goat »

diminoten wrote: post #200
escape_goat wrote: post #172

Earlier quoted context omitted.

I believe you should reread the previous parts of the thread, including your own, because it seems like your understanding of the positions in this argument have shifted. melling isn't demanding that arbitrary experts make elaborate posts on HN for his or her education and betterment. Rather, melling seems to believe that people who present information as knowledge in the comments section should be able and willing t…

You've taken what I wrote and pushed it much further than I did. If you re-read what I've written, I'm not nearly as extreme as you present. Your argument hinges on me being extreme in my position, when in actuality I am not. I have not said anything nearly as absolute as you've implied. For example, I don't believe me using the words "lazy" or "wasting everyone's time" were an example of what dang refers to as "jabs…

Actually, you used the personal pronoun 'you', which is not used in English to describe an activity, but rather a person. This is unambiguous.

To me, your response on this matter indicates that I'm likely to get argumentation in reply to anything I say rather than discussion or honest reflection.

This is fine, if one likes argumentation for its own sake, which it is established that you yourself do; I, however, do not, so I'm going to disengage from this conversation.

Scanning your points briefly, I would in another context be happy to go back and re-examine my representation of your position, but will not do so, as I can't take the assertion at face value, and would anyways be wasting my time as per above. I will remember it as a possibility. I do not exactly remember your thesis in the terms in which you have now restated it, but it seems likely that we are largely talking at cross-purposes with regards to the nature of valuable discussion on HN. Experts seldom fail to speak with sufficient rigor or mind correction when they do so. And 'citing sources' can be a waste of time, or a courtesy to others, depending on the context.

I would not hesitate to link to information on HN if that was the source of my knowledge. It is more important to me that I be (eventually) correct than that I maintain an appearance of correctness.

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