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Batteries: How cheap can they get?

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Re: Batteries: How cheap can they get?

#61

Post by h0l0cube »

jonathanlydall wrote: post #30
jvanderbot wrote: post #17

I would love a 5-20kwh battery backup in my home, I even have a place for it. But when I called my local solar/battery installer they said that it was illegal to install grid-charged battery backups in home. I live in Minnesota. They even told me the power from a hypothetical solar rig is sold to the grid utility, not stored, and they give a discount on future winter rates as payment. This seems like a lousy deal.

Aside from it benefiting energy companies, is there any justification for such a law? In South Africa we’ve had load shedding on and off since 2008. It’s becoming pretty standard for middle class homes to have inverters with batteries and optionally solar. It does create an issue though that when a load shedding window ends, a whole lot of batteries start charging all at once (especially during non-daylight hours). A…

> Also due to load shedding, I don’t get full use of my batteries.

But your batteries will last much much longer at the lower cycle depth

Re: Batteries: How cheap can they get?

#62

Post by Tade0 »

jonathanlydall wrote: post #30
jvanderbot wrote: post #17

I would love a 5-20kwh battery backup in my home, I even have a place for it. But when I called my local solar/battery installer they said that it was illegal to install grid-charged battery backups in home. I live in Minnesota. They even told me the power from a hypothetical solar rig is sold to the grid utility, not stored, and they give a discount on future winter rates as payment. This seems like a lousy deal.

Aside from it benefiting energy companies, is there any justification for such a law? In South Africa we’ve had load shedding on and off since 2008. It’s becoming pretty standard for middle class homes to have inverters with batteries and optionally solar. It does create an issue though that when a load shedding window ends, a whole lot of batteries start charging all at once (especially during non-daylight hours). A…

If it's any consolation your battery will at least last longer than one which is always doing full cycles.

Re: Batteries: How cheap can they get?

#63

Post by duffpkg »

blacksmith_tb wrote: post #58
duffpkg wrote: post #19

Lifepo4 (lithium iron phosphate) batteries for the home are pretty cheap as of today. Power storage for residential use in a 48v metal rackable linkable system with battery management system (BMS) is $89/kwh shipped/duty paid from reputable chinese suppliers CATL/Seplos etc. You have to wait for sea shipping, add $30/kwh if you want to buy it in the US today. From the same suppliers sodium batteries are currently $13…

Sounds great, but are there actual businesses who will come to your home and do an install, or do you need to to become a mad-scientist electrician and DIY? I got quotes on getting an LG system a few years ago and it was 4X these prices (also for me a problem is that my 'ancient' panels from 2013 use a single inverter instead of microinverters, so if I touch the system I have to replace it all). I keep hoping there w…

All of the quotes and interactions I had with the local solar installers were reminiscent of the used car lot if not outright fraud. I was able to do what was permissible myself and a regular licensed electrician did the rest. The equipment is UL listed. There was some learning curve but I found the diysolarforum.com to be a pretty good resource to learn what I didn't know. I ran the whole setup standalone for about 6 months before switching the house over to it. The only problem that happened was a loose battery cable connection which the BMS and inverter alerted to and handled correctly.

Re: Batteries: How cheap can they get?

#64

Post by kkfx »

A small note: I have a domestic p.v. system with small LFP storage and well... It's ~3 years old and now the same battery capacity (8kWh) cost a bit less the THE DOUBLE, witch is ~9000€ instead of a bit more than 5000€...

Industrial battery prices are lowered, in China, definitively not here in the EU, and at this rates the expensive small UPS for a home, that's are such capacity, because to being semi-autonomous a typical home need at least 80-100kWh to avoid too deep DoD and support heating in new all-electric and very well insulated homes. And I talk about mild climate where there is enough Sun in the winter to have not the autonomy but at least margin also in December, January and February. Oh, and I talk about self-assembled systems like mine witch is legal here, but not legal in every countries, because retail prices for a complete systems installed by them are FAR more expensive, about THREE time more, enough to make the investment so expensive to be a nonsense.

Re: Batteries: How cheap can they get?

#66

Post by Ayesh »

blacksmith_tb wrote: post #58
duffpkg wrote: post #19

Lifepo4 (lithium iron phosphate) batteries for the home are pretty cheap as of today. Power storage for residential use in a 48v metal rackable linkable system with battery management system (BMS) is $89/kwh shipped/duty paid from reputable chinese suppliers CATL/Seplos etc. You have to wait for sea shipping, add $30/kwh if you want to buy it in the US today. From the same suppliers sodium batteries are currently $13…

Sounds great, but are there actual businesses who will come to your home and do an install, or do you need to to become a mad-scientist electrician and DIY? I got quotes on getting an LG system a few years ago and it was 4X these prices (also for me a problem is that my 'ancient' panels from 2013 use a single inverter instead of microinverters, so if I touch the system I have to replace it all). I keep hoping there w…

> do you need to to become a mad-scientist electrician and DIY?

I did my own a couple years ago, and it worked quite well on the first go. I got someone else to build the LiFePo4 battery pack (16 CATL cells for 48v with a JK BMS).

It was fairly easy to build. Mount panels on the roof, and wire everything (PV, battery, grid electricity if you want it, and the output) to the inverter. I added some extra steps to monitor usage and output, and a smart MCB. I also have a small shop that I can feed from solar power if the battery is almost charged and the sunset time hasn't reached yet.

See if you quotation is to export electricity to the grid. Those kinds of setups usually require a certified company to do the installation (to make sure the inverter syncs with the grid), but for off-grid setups, you can definitely DIY.

Re: Batteries: How cheap can they get?

#67

Post by duffpkg »

ManuelKiessling wrote: post #41
duffpkg wrote: post #31

Earlier quoted context omitted.

Yes. Totally disconnected, zero power bill. That home is in a jurisdiction where that is permissible.

How do you get through winter? I’m asking in good faith, I‘m using a PV installation myself and cannot see how I could realistically get off the grid.

This is in the american southwest so winters are very mild and the sun is still strong. Summer is the much more demanding part where AC is 90% of electricity use for the year. There would certainly be challenges in other locations but I think you could do the napkin math on it with panels being as cheap as they are. The solution to pretty much any deficit these days is to just add more panels. The biggest issue there is, is if you do not have sufficient space. My panels are ground mounted.

Re: Batteries: How cheap can they get?

#68

Post by specialist »

dzhiurgis wrote: post #53
duffpkg wrote: post #19

Lifepo4 (lithium iron phosphate) batteries for the home are pretty cheap as of today. Power storage for residential use in a 48v metal rackable linkable system with battery management system (BMS) is $89/kwh shipped/duty paid from reputable chinese suppliers CATL/Seplos etc. You have to wait for sea shipping, add $30/kwh if you want to buy it in the US today. From the same suppliers sodium batteries are currently $13…

Why tesla charges 5x for their Powerwall? I know their software is excellent, but I haven’t seen prices like that anywhere.

My guess: to throttle demand. Installers are generally in short supply and huge demand. So why not charge a premium?

Re: Batteries: How cheap can they get?

#69

Post by oezi »

davedx wrote: post #55
GaggiX wrote: post #28

Earlier quoted context omitted.

>I purchased pallets of used panels for more or less the cost of transportation ($34 per panel 270w) For comparison, I've seen pallets of new 24 410w panels at 58€ per panel (transportation included), hopefully I'll see similar deals in the future when I will ready to jump into solar. Edit: I'm mostly worried because I don't know how sustainable the industry is when you can buy solar panels at such dirt cheap prices.

It’s not sustainable. Solar panel producers are going to be in big trouble in 8-10 years I think.

In the 8 to 10 years panels will be even cheaper. Probably half of today. The price trajectory is still falling.

Re: Batteries: How cheap can they get?

#70

Post by jonathanlydall »

SoftTalker wrote: post #46
jonathanlydall wrote: post #30

Earlier quoted context omitted.

Aside from it benefiting energy companies, is there any justification for such a law? In South Africa we’ve had load shedding on and off since 2008. It’s becoming pretty standard for middle class homes to have inverters with batteries and optionally solar. It does create an issue though that when a load shedding window ends, a whole lot of batteries start charging all at once (especially during non-daylight hours). A…

Utilities get a local monopoly and guaranteed tariffs in exchange for the considerable investment in building out the supply grid and generating capacity, and the obligation to maintain it. If individuals are allowed to opt-out, that changes the financial promises made to the utilities. Of course this was mostly done at a time before it was economically feasible for anyone to go off-grid with solar and batteries. I q…

I agree it would be much more efficient on the whole if the grid manages energy storage in bulk.

Unfortunately over here we have a monopoly awarded state owned power producer which has a history of incompetence and corruption.

Maybe at some point our grid can be trusted to be reliable, but in the meantime everyone is either installing their own batteries or having no electricity for hours at a time. Tragic, but what else can you do.

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