California utility augments 1,800 air conditioning units with “ice battery”
A Santa Barbara-based company called Ice Energy has partnered with NRG Energy to deliver 1,800 “ice batteries” to commercial and industrial buildings served by electric utility Southern California Edison (SCE). The units are expected to reduce air conditioning bills by up to 40 percent and eliminate 200,000 tons of CO2 over the next 20 years.
Ice Energy has been building ice-based cooling systems since the early 2000s. Much like pumped storage or compressed air “batteries,” Ice Energy essentially stores electricity by drawing power from the grid at non-peak times to freeze water in a special container. Then at peak times, when the cost of electricity is high and grid operators are struggling to keep up with demand, Ice Energy’s systems kick in and use that block of ice to cool the space that the air conditioning unit normally serves.
(Score: 2) by EvilSS on Sunday May 07 2017, @02:03AM (9 children)
(Score: 2) by requerdanos on Sunday May 07 2017, @02:02PM (8 children)
From TFA [arstechnica.com]:
Ice Energy says IceBear 30 units can eliminate up to 10,000 lbs of CO2 per year.
(Emphasis mine). I didn't find the math they use in the article. On Ice Energy's website [ice-energy.com] they say that the CO2 savings comes from displacing peak generation plants and by being "renewable friendly," but also on the "Ice Energy Says" basis.
(Score: 2) by EvilSS on Sunday May 07 2017, @04:47PM (7 children)
(Score: 2) by requerdanos on Sunday May 07 2017, @06:04PM (6 children)
Not sure your argument here, you basically just repeated what I said.
Sorry, I guess it's something like the following:
- Ice Energy says they will save so many tons of carbon, but I don't see any evidence to back it up.
- They say that the displacement will avoid using peak generation during the day to save carbon release, but drawing power at night draws from sources that necessarily exclude solar and therefore are more likely to have a higher carbon-output-source factor than during the day, when solar is in the mix.
- Since no system is 100% efficient [imascientist.org.uk], they are necessarily using more energy for the same amount of air cooling. Even if they cool the water at night, when it is easier to cool water all other things being equal, it still remains a fact [livescience.com] that no system is 100% efficient, and so they are necessarily using more energy for the same amount of air cooling. I am not sure how they are saving carbon emissions by using more energy, and that during a time when no solar is online. Not saying that's impossible; just don't see how this system would do it.
- According to TFA, the system is not being chosen on its merits but rather because the California legislature requires a certain amount of off-grid energy storage regardless of the sane-or-zany factor involved; saying nice things about this system might be true, or might simply be an effort to make the choice less unpalatable.
- For some of Ice Energy's smaller custom systems, using excess solar whenever it's available is a component, but emphatically not this system: This is a system by which SCE can unilaterally turn off large customers' air conditioners at peak times of the day, replacing A/C with frozen-the-night-before Ice-based heat transfer for a few hours on a massive scale to manage demand.
- Their website technical section seems to contain more hand-waving than mathematics, and I don't take their word for it. These matters are complex: Maybe they are telling the truth and not being misleading in the least. I doubt it.
Apologies for the previous ambiguous post--it made sense in my head at the time, as do so many things.
Energy management, renewable & sustainable energy, and energy cost are tightly intertwined issues that we as a society must, must face, advance, and keep ahead of to avoid a transition to regression instead of progress. I salute Ice Energy for working on the issues; I salute the state of California for recognizing the need and taking action. Doesn't mean I trust them, but I am glad someone's doing something. Admittedly, for all the designs that wander through my head, I have built precious few of them and none of them is currently harvesting nor providing energy.
(Score: 2) by EvilSS on Sunday May 07 2017, @08:57PM (2 children)
- The savings comes from displacing peak demand, and reducing the use of CO2 generating peaker plants that come online to help fill in generation demand during peak times when the normal grid generation plants can't keep up. Those other plants run 24/7 so their output is fairly stead, the peakers add additional output. Elimination of those would result in a net CO2 reduction.
- The peaker plants it is being deployed to address are not solar, they are fossil fuel systems. These are systems turned on during high peak times. Eliminating those most definitely reduces carbon output. That it uses sources available at night doesn't affect the overall CO2 output over a 24 hour period, as those plants will be operating 24/7 anyway. Taking the peaker plants offline is the goal here.
- The system does not have to be 100% efficient to be more efficient than running a multi-ton AC, it just has to be more efficient than the equivalent cooling time it replaces. Remember it's replacing AC for up to 3 hours, not running along side it. That means while the ice system is running, the AC compressors are not.
- You are making a statement not supported by TFA. Can you back up that it was not chosen for it's merits as an energy storage platform?
- This is due to the fact that those systems do not also have solar deployments at the site. Again, however, reducing peak demand means reducing the use of natural gas peaker plants, which produce CO2 in excess of the normal grid generation.
(Score: 2) by butthurt on Sunday May 07 2017, @11:54PM (1 child)
> Remember it's replacing AC for up to 3 hours, not running along side it. That means while the ice system is running, the AC compressors are not.
Ice Energy's promotional video from 2011 shows it running alongside an existing air conditioner.
https://www.youtube.com/watch?v=g69Y9B3nZOI [youtube.com]
(Score: 2) by EvilSS on Monday May 08 2017, @05:00AM
(Score: 2) by EvilSS on Sunday May 07 2017, @09:09PM
(Score: 2, Informative) by khallow on Sunday May 07 2017, @10:16PM (1 child)
- Since no system is 100% efficient [imascientist.org.uk], they are necessarily using more energy for the same amount of air cooling.
Unless they aren't. Lower temperatures at night are a big deal since you're dumping the heat into the cooler night rather than into the hottest parts of the day. It doesn't have to be 100% efficient in order to be more efficient than 100% efficient daytime AC.
(Score: 1) by butthurt on Sunday May 07 2017, @11:43PM
Yes, thank you. That's the idea I was attempting to convey in my comment about Carnot efficiency.
/comments.pl?noupdate=1&sid=19375&page=1&cid=505697 [soylentnews.org]