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New technique stores summer heat until it's needed in winter
- btbuildem 10y agoIs this something that could be used in a dense urban residential setting? Is the reaction extremely volatile? Does this require a high-tech ultra-low-tolerances system, or can it be DIY-ed? I can see having a setup on a condo balcony (esp. if you're facing south / west), with heat exchangers on an otherwise-unused wall, and a few cylinders of NaOH. As long as the kit doesn't blow the wall off the building if it leaks or some such disaster..
- klodolph 10y agoI'm not sure what you mean by "volatile reaction". NaOH is not super dangerous but I wouldn't trust a DIYer with large quantities, since it's so alkaline. You can find out more online by just searching for "MSDS sodium hydroxide" and you'll find phrases like "very hazardous in case of skin contact". A leak in some DIY setup would easily have horrific / disfiguring consequences.
- dpark 10y agoIt won't explode if it leaks but it might kill the people on the balcony beneath yours.
- steffenfrost 10y agoIf the system scales based on the fluid, the $/kwh could get pretty low. Would be interesting what a MWh amount of heat storage would cost.
- petre 10y agoAssuming the 50% NaOH solution releases half the amount of heat released from dissolving dry sodium hydroxide in water, to store 1 MWh you would need about 6.5 tonnes of sodium hydroxide. The price for NaOH pearls 99% is 300-400$ per 1 metric tonne.
- pdog 10y agoA simpler method is to grow crops and eat them.
- peter303 10y agoThe opposite of saving winter ice for the summer was popular in the 1800s before mechanical refrigeration. Ice can last many months if insulated by sawdust below ground.
- nom 10y agoI was just about to post the same thing :D The storage facilities are called Ice House [0]. The large ones stored several thousand metric tons and could last through the whole summer, depending on the climate. 0: https://en.wikipedia.org/wiki/Ice_house_(building) https://en.wikipedia.org/wiki/Ice_house_(building)
- lucaspiller 10y agoA whole industry was created based on this: https://en.m.wikipedia.org/wiki/Ice_trade https://en.m.wikipedia.org/wiki/Ice_trade
- EvanAnderson 10y agoPrinceton had an "ice pond"[1][2] in the early 80's. The project was run by Dr. Ted Taylor[3] (who worked on the Manhattan project and later the Orion spacecraft-- huge nuclear bomb-powered spaceships!). Snow machines made slushy ice that was stored in pond covered with insulation. Water was pumped through the pond in the summer to provide cooling. It worked well and at the end of the summer there was still ice in the pond. I read about this as a kid reading Freeman Dyson's "Imagined Worlds"[4]. Dyson's commentary is definitely worth reading. (Anything written by Freeman Dyson is worth reading.) A cheese factory used ice ponds[5] for about 10 years, eventually abandoning them because the ice didn't last through the summer and it was difficult to maintain[6]. [1]: https://en.wikipedia.org/wiki/Ice_pond https://en.wikipedia.org/wiki/Ice_pond [2]: https://www.washingtonpost.com/archive/opinions/1981/08/02/the-ice-pond-age-cometh/51396081-09a8-4afe-b69c-1217b4700408/ https://www.washingtonpost.com/archive/opinions/1981/08/02/t... [3]: https://en.wikipedia.org/wiki/Ted_Taylor_(physicist) https://en.wikipedia.org/wiki/Ted_Taylor_(physicist) [4]: https://books.google.com/books?id=MOC8UJPuvO8C&pg=PA42 https://books.google.com/books?id=MOC8UJPuvO8C&pg=PA42 [5]: http://www.nytimes.com/1984/06/03/nyregion/dairy-hoards-500-tons-of-ice-for-the-summer.html http://www.nytimes.com/1984/06/03/nyregion/dairy-hoards-500-... [6]: https://www.farmshow.com/a_article.php?aid=15129 https://www.farmshow.com/a_article.php?aid=15129
- willholloway 10y agoThere is no need to store summer heat for the entire winter, which would necessitate a far larger capacity system. One would only need to store solar thermal energy that is available on any sunny or partly sunny day for night time and cloudy days. Where I live about half of all days produce abundant solar thermal energy even in the depth of winter. Calculating in night time, you end up with about 12.5% of total winter time having abundant free thermal energy. So one would need to build a system of solar thermal collectors about 8 times the size one would need to heat a house on a sunny winter day, and that is not a very big system. Space wise I think it would work for single family residential homes on .25 acre lots if the house was designed for it from the start.
- mikeklaas 10y agoWhy not just store that solar energy as electricity, and use the electricity to power heat pumps when needed?
- willholloway 10y agoThat is a good question and the answer comes down to physics and the economics of battery technology vs this technology.
- mistermann 10y agoIt might be that one or the other is better "in general", but I can see that this technology could have benefits in certain scenarios, maybe long term storage in remote, cold climates.
- derblitzmann 10y agoThe main issue is that every transfer of energy incurs losses, thus ineffeciency grows. Though the practically can be examined to determine how efficient an energy storage process can be versus no storage.
- scotty79 10y agoMore expensive, losses at gathering, conversion, storing steps. Additional complexity of heat-pumps. What they describe is basically few twisted pipes and a tank. I'd feel way more enthusiastic about the whole idea if it didn't involve large quantities of highly caustic 30%-50% NaOH solution.
- d_burfoot 10y agoI think this kind of technology has enormous potential to improve human life. Bad weather is a huge, chronic problem that makes almost everyones' life substantially worse. Just the other day my aunt broke her wrist after slipping on a patch of ice. One question though: why do they need a special high-tech material to do this? Why can't they just bubble warm air through cold water in the summer and vice-versa in the winter? Water has very large heat capacity, 400x that of air by volume.
- vtange 10y agoWell, isn't that what happens in oceans already? That is why coastal cities are more temperate and experience more moderate swings than inland cities. I'd imagine there's not enough water to do this inland..
- d_burfoot 10y agoThat's true for west coast cities, but not for east coast cities like Boston and New York, which experience terrible temperature extremes. How much water do we need? I wouldn't try to affect large regions, just specific urban areas. The water doesn't actually have to go anywhere, it just sits around storing heat. All we have to do is bubble a lot of air through it. As a nice side benefit, this should clean the air. (This is my version of the Reber Plan).
- ars 10y agoIt's true for Boston and NY as well. Those cities have milder weather than the cities inland of them.
- dpark 10y agoAre you proposing that we capture heat this way to warm houses (in which case it's a terribly ineffective and inefficient system) or to actually raise the outside temperature? If you're proposing the latter, there's just no way. Water might store 400 times as much heat per unit as air, but there's an absurd amount of air hovering around a town and an enormous area that air mixes with constantly.
- ChuckMcM 10y agoThis is a really neat system. I wonder how many BTUs per liter you can store ...
- phurley 10y ago; I IUI uii link wj
- sebyddd 10y agoThere is a better solution already implemented.. https://youtu.be/sbX6K7ky9LQ https://youtu.be/sbX6K7ky9LQ
- ZeroGravitas 10y agoThis reminded me of a similar system that uses the same tech as those hand warmer things that have a chemical that changes state, either absorbing or releasing energy. They also talk about absorbing heat and physically transporting it. The example they have was waste heat from industrial processes being shipped via canal to a district heating system. http://www.sunamp.com/ http://www.sunamp.com/
- a-b 10y agoIs this about the global warming?
- grzm 10y agoThe article describes a method using NaOH for long-term storage and transfer of heat, taking advantage of excess heat in the summer to use it during the colder months of winter.
- lgats 10y agoI'm not quite sure I want sodium hydroxide in my house... https://en.wikipedia.org/wiki/Sodium_hydroxide https://en.wikipedia.org/wiki/Sodium_hydroxide
- mirimir 10y ago> The heated water generated in the process of condensation is then transferred to a geothermal probe (generally loops of pipes embedded vertically in the ground) for storage and retrieval. That is a neat approach. It works well for solar-heated water. Where winters are very cold and summers hot, one can also have cold-storage loops for summer cooling. I'm not sure about the NaOH thing, however. I get that it enables heat transport. But as scotty79 notes, transporting concentrated NaOH is hazardous. It's already done, of course. But the scale for heat transport would be much greater than as chemical feedstock, I think.
- tmaly 10y agoI wonder how efficient this process is. The article did not state that figure.
- failrate 10y agoPlus, the 50% recharge rate indicates that the medium would need to be replaced every couple of years.
- ars 10y agoI think you misread the article, that figure is the concentration diluted with water.
- failrate 10y agoPlus, the 50% recharge rate indicates that the medium would need to be replaced every couple of years.
- ars 10y agoI don't think it matters - you are getting your heat from ambient air.
- politician 10y ago(Wikipedia:) Worldwide production [of sodium hydroxide] in 2004 was approximately 60 million tonnes, while demand was 51 million tonnes. So it might be relatively cheap to acquire the working material.
- Mizza 10y agoIt's pretty horrible stuff though. I really don't think I'd want pipes full of that in the basement of my home.
- giardini 10y agoYes, once worked with this stuff in a QC lab. I can't imagine having it in homes. Undoubtedly there are better alternatives. This makes more sense than promoting the use of ammonia as a climate-friendly refrigerant, but barely (the ammonia will kill/burn/maim you faster): https://ec.europa.eu/clima/policies/f-gas/alternatives_en https://ec.europa.eu/clima/policies/f-gas/alternatives_en http://www.goodway.com/hvac-blog/2009/08/ammonia-as-a-refrigerant-pros-and-cons/ http://www.goodway.com/hvac-blog/2009/08/ammonia-as-a-refrig...
- jessaustin 10y agoAmmonia is already a product that is stored and used by lots of people. It is a common fertilizer. There are guidelines for safety equipment and tank maintenance, but I'm not convinced that everyone follows those. I think ammonia's next big application will be as an easier-to-use form of hydrogen for fueling ICEs with renewable energy.
- cobbzilla 10y agoI agree. One would hope that when this research-level technology reaches the market, they can effectively isolate and contain the NaOH, and have some solid safeguards against malfunctions. On the optimistic side, we've mostly succeeded in doing that for other volatile things like gas tanks in cars and lithium batteries in electronics. On the pessimistic side, the failure modes can be very catastrophic! I'd definitely want to know what failsafe mechanisms are in place to prevent my house from blowing up before I'd consider using it.
- WalterBright 10y agoAnother way is to simply use the ground. Dig trenches, lay in pipe. The ground is cooler than the air in summer, can warmer in winter. I read that using it as a heat exchanger can cut HVAC bills by 30%.
- iaw 10y agoThis works wonderfully at lower population densities but starts breaking down when you get past a threshold.
- DannyBee 10y agoIt actually scales quite well, it just turns into "don't have one unit per person". I mean, even regular heat pumps break down at certain population densities due to the same problem.
- curtis 10y agoThese systems are pretty popular, even my dad has one. The problem is they're also pretty expensive -- on the order of $20,000. At that price it could take a long time to hit break even, at least in the U.S.
- beamatronic 10y agoAccording to this [1], the 2015-16 estimated average residential winter heating bills for a propane user ( the highest ) was $2,569. The cost of this system is approximately equivalent to 7.8 years of heating costs. If this system saved 50% on the bill then it breakeven is about 15 years out. These numbers aren't too far from solar historically, if I recall correctly. [1] http://www.mass.gov/eea/energy-utilities-clean-tech/misc/household-heating-costs.html http://www.mass.gov/eea/energy-utilities-clean-tech/misc/hou... edit: these numbers were for Massachusetts specifically
- bluGill 10y agoWith improvements in refrigeration technology they may never. If you compare installing geo-thermo 10 years ago vs someone who installed an air source heat pump, and then upgraded (at optimal times picked on hindsight), the latter has paid less for equipment, and his yearly costs are now less as well. Geothermal equipment is enough more expensive that upgrading doesn't help those numbers much even though the expensive pipes in the ground are still perfectly good. Of course there is eventually a limit in efficiency gains. When you reach that limit geothermal has advantages that will pay off eventually. 10 years ago at least you should not have installed geothermal. What the next 10 years will bring is beyond my knowledge.
- ars 10y agoI usually find these types of new green technology to be impractical, and obviously not going anywhere (store energy by dragging a train uphill for example). But this actually looks like it would work!
- aaronbwebber 10y agoWhy wouldn't storing energy by dragging a train uphill work? It's basically the same as pumped hydro storage, and that's being used right now.
- wlesieutre 10y agoConstruction supposed to begin this year - http://www.utilitydive.com/news/first-of-its-kind-rail-energy-storage-project-targets-role-in-caiso-ancilla/417817/ http://www.utilitydive.com/news/first-of-its-kind-rail-energ...
- ars 10y agoThat is greenwashing taken to anther level. They are not just pretending to be green, they are actually doing harm and wasting money that could be used in better places. If you read the article you'll notice they refuse to compare to pumped hydro (because if they did people would laugh at them for how expensive they are). They are happy to compare to batteries though, because those are also not a usable way to store energy in bulk. Sigh. With projects like this is it any wonder people are so skeptical of "green technology"? There has to be some political reason this is getting built, because there sure isn't an economic or environmental one.
- imaginenore 10y agoPumped hydro only works in areas with the hydroelectric plants. That train seems like a decent solution for everywhere else.
- dpark 10y ago
- seiferteric 10y agoThis sounds pretty cool, but are there any numbers on energy density?
- iaw 10y agoI had looked at dry storage of heat using NaOH a while ago, I can't recall the energy density but it's on wikipedia. The bigger problem that I found was that the efficiency was horrible. I wonder if having it in solution resolved this problem, if that's the case then there's going to be some applications for this with even a reasonable energy density.
- petre 10y agoWikipedia says 44.51 kJ/mol, so that should be 309 Wh/kg, for dry NaOH dissolved in water. The amount of energy needed to heat 1 kg of water with 1 K is 1.16 Wh. So the heat released from dissolving 1 kg of NaOH in water will heat 10 liters of water with about 26.64 K. https://en.wikipedia.org/wiki/Enthalpy_change_of_solution https://en.wikipedia.org/wiki/Enthalpy_change_of_solution With the heat released from 20 kg of NaOH dissolved in water you could heat 100 liters of water with 53,3 K, enough to take a hot bath.
- chmod775 10y agoIt is also more than twice as dense as water, so the amount needed to heat 100 liters of water with 53,3 K will only have 1/10th the volume of said water. So even if you only use a small area in your basement for energy storage, it should be enough to have hot baths all winter...
- dpark 10y ago20kg of lye for a bath seems like a lot. That's 2000 kg just to get through the coldest 3 months. Multiply that by the number of people in the house. And then remember to add space for all the water you'll have to mix with the lye to extract the heat. And actually double the water space if you're going to keep it after recharging instead of dumping it. That sounds like a huge amount of space.