Wondering if that’s a standard UPS or is it what Tesla has been saying they would do with old Tesla car batteries
I don’t think it’s either Karen. The batteries in a UPS just gives enough time to perform an orderly shutdown or for the generators to kick in and at the price of these things I doubt they’re recycled anything, yet.
Thank you Paul, not just low wattage items, charging vehicles and heating etc. To silence the comments about battery polution at the end of their vehicles life, I would only too happy to have the battery for its second life as a powerwall.
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Its a grid tie inverter, and battery backup, semi smart and should contain old batteries but not enough old batteries yet so mostly new as I understand, because batteries are lasting longer than initially thought.
Smarter still versions like GivEnergy units are available.
Great thinking John, I know that old car starter batteries still hold a full charge, they just haven’t got the punch required to turn a car engine.
Shame you didn’t’ use my code and we both would have got €10 off!
Yes, it was a bit of an impulse (no pun intended) decision 
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Yes, makes you wonder or I certainly do, why they quote the the figures they do when they barely maintain power for a few minutes.
You get to decide the level of continuity of power based upon the capacity of UPS you buy. The batteries also expire and need changing every 5 years or so.
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It’s something I find more than a bit irritating as well.
Ultimately there are two scenarios that UPSes cover - there is the “orderly shutdown” scenario which really does just need a few minutes of backup power and there is the “bridging” scenario where you want to keep going over short (say, up to a couple of hours) power outages.
Most home users, to be fair, only need the “orderly shutdown scenario”.
I recently (finally) bought a UPS - as I run my own mail servers (plus a few other supposedly 24/7 bits ‘n’ bobs) I actually want the “bridging” scenario so I bought an APC Smart-UPS 1500 (actually a 2nd hand unit from eBay), this is rated at 1000W/1.5kVA with about 400Wh (2 x 12V 18AH) of battery. I get about 60mins offline given that I have a 100-150W (depending on whether the monitor is on) load.
Annoyingly it threw a wobbly the other night went onto battery and then declared an overload shutting stuff down - to be honest this worries me much more than battery life as a UPS is supposed to increase upime not reduce it.
I’ve had large datacenter UPS and generators but never a home one. I think I read that some can signal the system that power has failed and trigger an automatic shutdown?
On a similar security theme, I decided to augment my automatic backups with a LaCie 20TB raid array. Now even when the power drops unexpectedly data loss should never be a problem.
When is 400Wh not 400W for an hour? When its a UPS!
Well when it’s an SLA really.
A 12V 18AH battery will not, generally, be able to supply 18A for an hour.
That might seem counterintuitive but it is to do with the battery’s construction. If you were to apply a lower load, typically 1/10th of the rated AH capacity the performance will approach the rating, so 1.8A for 10 hours would probably be achievable.
After that you have to consider the conversion efficiency of the UPS - which is never going to be 100%
Yes agree, its strange or is it that we do not work on real world figures for so many things these days. A lead acid battery can only use around 50% of its stated output without sustaining damage. Lithium iron phosphate batteries around 80%.
400Wh is at best 200Wh less as you said conversion factor so your system is around 150w for 60mins.
On a backup project for work to keep radios working in the event of power outage, I bought a larger capacity external battery and connected that in place of the original battery to provide an hour of use.
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It’s the “up to” world. So many things are rated as “up to” that will never achieve the top end of the quoted range. From investments to milage and everything in between. Of course, “up to” conveniently includes zero.
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Yes, in the world of music we know RMS the millennials know peak music.
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We switched to ekWateur about 18 months ago, having had EDF for ages. This was thanks to a “group purchase” campaign run by the consumer association Que Choisir.
The price is very competitive, and the transfer was painless.
https://ekwateur.fr/electricite-verte/
Edit: there’s a new campaign, you can sign up here Energie Moins Chère Ensemble - Achat groupé d'énergie - SAS Que Choisir
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