Hydrogen battery for the home - Page 1
Forum section: electronics / general

author: VK3DRB
author_rank: Super Contributor
timestamp: January 20, 2021, 11:13:22 pm
content: It sounds too good to be true, especially considering the energy density of hydrogen. Price is $US 26k for a home unit.https://lavo.com.au/lavo-hydrogen-battery/https://www.theage.com.au/environment/climate-change/world-s-first-domestic-hydrogen-battery-developed-by-australian-firm-20210120-p56vkd.html

author: ConKbot
author_rank: Super Contributor
timestamp: January 20, 2021, 11:34:38 pm
content: I'd agree the hydride cannisters look a tad small compared to the energy storage claims, but I'm not exactly familiar with the energy density of that sort if thing. I know the brunton hydrogen powerbank seemed to be about equivalent to lithium ion in terms of H2 can size vs what I'd expect from an equivalent battery. Removable for household use seems a bit of a stretch. Its not outrageous enough to be utter bullshit, but still gives me "hmm not sure about that, I wouldn't adopt it first" feeling.Membrane life and replacement cost, along with how much other consumables cost is also a big factor. I'm assuming there HAS to be an ion exchange resin filter to provide DI water to the electrolyser.

author: nctnico
author_rank: Super Contributor
timestamp: January 20, 2021, 11:35:32 pm
content: They are not the first. In the NL similar units have been installed already but these are using pressurised hydrogen instead of using a chemical conversion. Chemical conversion does have the advantage of offering high energy densities. During the conversion to hydrogen each molecule of Sodium borohydride provides two atoms of hydrogen (the 2nd atom from the water that the process uses). The downside is that the chemicals involved are pretty toxic.

author: Gregg
author_rank: Super Contributor
timestamp: January 20, 2021, 11:46:38 pm
content: I personally wouldn’t want to install the first generation of anything like this.I’m sure insurance companies are subtly modifying all policies upon renewal or a new policy to exclude coverage in case of problems either directly or indirectly involving household energy storage devices.

author: Red Squirrel
author_rank: Super Contributor
timestamp: January 21, 2021, 12:30:23 am
content: I'd love to see something like this be viable and in principle I think it can be. But part of me also figures if it is viable than it would already be done.

author: Marco
author_rank: Super Contributor
timestamp: January 21, 2021, 12:32:18 am
content: Even if they have a hydride which can be efficiently regenerated, I don't really see the point for a home ... the size and weight of a high pressure tank are not a big deal. Just do high pressure electrolysis and be done with it. Of course that still leaves the problem of the inefficient electrolyser and the expensive fuel cell.ConKbot, why would you use ion exchange when RO equipment and consumables are as cheap as they are?

author: nctnico
author_rank: Super Contributor
timestamp: January 21, 2021, 12:37:47 am
content: Quote from: Red Squirrel on January 21, 2021, 12:30:23 amIn the end you have to calculate back to the cost per kWh stored. They claim 20,000 cycles. Given the capacity of 40kWh that is 800MWh of total energy storage. At a price of $30k that is 3.75 cents per kWh. That is not insanely expensive.

author: Red Squirrel
author_rank: Super Contributor
timestamp: January 21, 2021, 03:11:58 am
content: Wow why only 20k cycles? I would figure something like this would be basically unlimited. Or is that just accounting for wear and tear of moving parts? I presume this is stuff you can just change over time as part of regular maintenance though. Ex: don't need to completely swap out the whole thing. Though guess this is where right to repair comes in... if they go the Tesla route then they won't make it easy to get parts.

author: nctnico
author_rank: Super Contributor
timestamp: January 21, 2021, 11:40:08 am
content: Quote from: Red Squirrel on January 21, 2021, 03:11:58 am20k cycles is a whole lot better compared to Li-ion batteries. And likely it is possible to exchange the borium hydrate filling (which then can be purified / recycled for new use) instead of replacing the whole thing.

author: NiHaoMike
author_rank: Super Contributor
timestamp: January 21, 2021, 12:59:34 pm
content: LTO batteries can already do 20k cycles. Then there's thermal storage which would only cover HVAC and hot water but at a way lower cost than any other known storage technology and no inherent limit on the number of cycles.

author: wraper
author_rank: Unknown
timestamp: January 21, 2021, 01:28:24 pm
content: And specs say nothing about efficiency. I wonder why...

author: wraper
author_rank: Unknown
timestamp: January 21, 2021, 01:34:44 pm
content: Quote, Also I doubt fuel cell will last anywhere close to match 20k "Hydride Cycles" claimed. IMHO they decided to stay silent about uncomfortable things.

author: nctnico
author_rank: Super Contributor
timestamp: January 21, 2021, 03:02:32 pm
content: Quote from: NiHaoMike on January 21, 2021, 12:59:34 pmStill... what is the cost per stored kWh (Levelized Cost of Storage / LCOS )? In the end that is all what matters.QuoteBut then you only have hot water.

author: Red Squirrel
author_rank: Super Contributor
timestamp: January 21, 2021, 11:19:17 pm
content: Heat is what uses the most energy in a home so heat storage could be interesting if turned into an utility. I wonder, how viable would it be to have "heat service" as an utility. Instead of gas line coming to the home you have two pipes with heated water, an in and an out. These connect to the larger lines that would be going to every other home. You get charged based on the delta T of the in/out so basically the more heat you extract the more you get charged. Ideally this would need to be cheaper per BTU than natural gas to be viable though. This network could also go to factories and other key areas that may have waste heat, to add to the system. Heck even homes could have the option to add heat to the system if they want to. For example if you have a wood stove you could decide to add heat to the system and it would make the meter go backwards as the delta T would now be positive.This would only make sense if green energy is used to generate the heat though. If it just goes to a big natural gas plant then it probably makes no sense vs running gas to each home.

author: nctnico
author_rank: Super Contributor
timestamp: January 21, 2021, 11:58:55 pm
content: Quote from: Red Squirrel on January 21, 2021, 11:19:17 pmI have been living in a house which has exactly that for the past 20 years. It works pretty good (the hot water tap runs just as fast as the cold one) and is reliable. However laws had to be put in place to make sure it is not more expensive compared to having a natural gas boiler. It isn't exactly cheap to build. With natural gas being phased out in the Netherlands a lot of new 'city heating' systems are being rolled out at the moment. The heat comes from electricity power plants; the common claim is that it saves about 30% of CO2 emissions compared to having a boiler yourself. IIRC I pay about 38 euro per GJ.

author: NiHaoMike
author_rank: Super Contributor
timestamp: January 22, 2021, 01:07:48 pm
content: Some apartments near the Texas A&M university work that way for hot water, but without the metering. There's a CHP power plant on the campus that generates a lot more heat than is needed on site, so the excess gets sold to nearby areas.

author: Red Squirrel
author_rank: Super Contributor
timestamp: January 22, 2021, 04:51:56 pm
content: Wow that's really neat did not figure that was actually something already being done.

author: jmelson
author_rank: Super Contributor
timestamp: January 22, 2021, 04:54:18 pm
content: Quote from: ConKbot on January 20, 2021, 11:34:38 pmI have some experience with hydride storage tanks. We used them for an air pollution instrument that was to be operated in an aircraft. They were LOTS lighter, and were not able to blow out their entire contents instantly like a gas bottle. We were told (didn't actually measure it) that these tanks at 300 PSI held about as much Hydrogen as a standard tank the same size at 2000 PSI. They were filled with something like Titanium dust, which adsorbed the hydrogen in tiny surface cracks. Due to the lower pressure, the tanks were Aluminum, not steel.Jon

author: jmelson
author_rank: Super Contributor
timestamp: January 22, 2021, 04:57:53 pm
content: Quote from: Red Squirrel on January 21, 2021, 11:19:17 pmDistrict heating is used in a number of places. It is quite common in Manhattan, NY, many apartment buildings have district heating. It is supplied in the form of steam, not circulating hot water. I think by using steam, they can put water meters on the returning condensate and then bill by usage.District heating is apparently also quite common in Russia and Scandinavia.Jon