Thinking of a battery option for my home

[Woodsplitter67]

Im thinking of some battery storage for my home. Not sure which ones are the best option. I have solar and also I have a generator. I understand that charging my battery via generator is not an option. I dont understand why. I have read that outside storage is an option but if its cold the battery won't charge. Any one have storage that they want to talk about

 

[begreen]

I don't know why a generator wouldn't charge it, but the genset might need to be 240vac with very clean power and stable 60Hz output. There are some battery packs that are generator/solar chargeable, but they can be pricey. Yes, battery packs work better when warm.

 

[ABMax24]

What's the end goal of the battery? Store your solar output for usage during the night? Or for use in a grid outage? Or both?

 

[peakbagger]

I have a couple of fork lift batteries on my solar trailer. It gets charged up via a Kubota Diesel generator through my Sunny Island Inverters if they think they drop down too low. Economically it does not make a lot of sense to charge a battery with diesel as its just cost too much but lead acid batteries need to be equalized every so often and its best done with generator rather than solar. RIght now the generator is unplugged so if I do need to equalize the batteries, it does it off grid power. FLAs are old tech, most home battery solutions are Lithium chemistry due to depth of discharge capability and life. Cost per KWhr of storage is rapidly getting on par with FLAs.

There is no technical reason why you cant charge with a generator if the battery charge controller is capable of charging lithium batteries which have different settings than FLAs, off grid folks have done it for years. If on the other hand you are getting a subsidy off a utility or selling back to utility, they may prohibit it as its not "renewable" power.

 

[Solarguy3500]

Im thinking of some battery storage for my home. Not sure which ones are the best option. I have solar and also I have a generator. I understand that charging my battery via generator is not an option. I dont understand why. I have read that outside storage is an option but if its cold the battery won't charge. Any one have storage that they want to talk about

I assume you have solar already, right? What type of inverter system do you have? SolarEdge, Enphase?

Both of these inverter manufacturers now have storage batteries that work with their systems.

Enphase has AC coupled Lithium iron phosphate batteries that come in 2 sizes, the IQ Battery3 and IQ Battery 10, which is just 3 of the IQ3 batteries in a larger case. The Enphase battery system is the only commercially available battery system that I am aware of that has the capability to use battery and generator at the same time using the Enphase System Controller 2 and IQ8 micro inverters. It also supports Sunlight backup without batteries and with a generator to make the sunlight backup more reliable so the microgrid doesn't collapse every time a cloud goes over. There are limitations of course, and one of them with Enphase is that it limits the number of backed up circuits to a relatively small number of circuits.

Solaredge has their own branded batteries called Solaredge Energy Bank as well as the LG RESU 10H and 16H batteries. Both of these are DC coupled Lithium ion batteries and if you have a regular Solaredge inverter, you'll have to buy a new one as part of the battery retrofit. You'll need one of the Solaredge Energy Hub inverters which will probably cost around $2,000 - $3,000 in addition to the cost of the batteries.

Having batteries outside is not an option unless you live in a climate like southern California. In a cold climate, the batteries will be adversely affected by cold, and most of the manufacturers have language in their warranties that says if the batteries are exposed to temps below a certain threshold for a certain number of days in a year period the warranty is void.

 

[peakbagger]

IMHO, battery tech is rapidly changing and right now the proprietary systems seem to rule the roost. Unless your utility is throwing a lot of money at you (like Massachusetts) hold off, prices will do down and choices will expand. Enphase and Solaredge seem to make the forums as problematic technology. It makes a lot of promises but it's not mature, that means a lot of software updates that on occasion brick the system until the installer that installed the system comes over to get it running again (good luck if they are out of the picture). Vehicle to grid (V2G) seems to be a standard that might become common since the car industry is behind it, but its not ready yet.

My Sunny Island system is relatively old tech but mature, no need to be in constant connection with the "mothership". The Schneider Electric (formerly Xantrex) also is mature technology with a lot of flexibility. The trade off is the entry price is high but the flexibility is far greater.

 

[woodgeek]

I agree with PeakBagger, is you want a turn key battery system that will work with your solar, the grid and your home, you need a package system like the Tesla PowerWall. Some utilities will pay you monthly to control your PowerWall for load management, but IIRC, I have only heard about that being a thing in MA.

If you want a backup system for running some loads, you can def build a battery bank and get an inverter and hook it up DIY, and charge it off your genny. But a lot of money for infrequent use.

For backup, you can just get an EV and run a $300 sine inverter off the 12V side to get about 1200W out continuous, 2 kW surge. And it is a lot less hassle than running a big genny, storing/rotating gas, and putting up with the noise. That's what I do.

 

[peakbagger]

Of course, you can go my way and pick up a $150K portable solar power plant for far less than the price of the parts. The auctions were 2 years ago but they still show up on auction sites although on many the batteries were abused. (Search for DC solar trailer or solar trailer on Fleabay and the like) Its relatively plug and play and AC coupled. If the house is islanded from the grid, it can control most (but not all) solar inverters in the house by frequency shifting so your existing solar system most likely will run off grid with no modifications. It works on my two Fronius inverters and a rack of Enphase 215s microinverters. If an automated transfer switch is installed between the utility meter and the main panel , it can be set up for automated switching from grid to battery and back. It will put out a steady supply of 240 VAC power at 50 AMPs with various duration surge currents available. Plug in a third Sunny Island and it will put out 3 phase. Inside the cabinets is a Midnight Solar charge controller for the PV panels and two Sunny Islands, one a primary and one a slave. Plenty of you tube videos on Sunny Islands. It has two forklift batteries totaling 54 KWH, in combination with the solar on the trailer and the solar on my house I could run a very long time off grid but I have net metering so for 7 or 8 months a year I am putting surplus power into the grid so it does not make sense to go off grid.

 

[Poindexter]

I agree with the implied opinions of @peakbagger and @woodgeek that pretty soon the economical choice is going to be to buy a wrecked EV "hit light front" and work the batteries in it while you use the savings to buy parts to get the EV on the road again as a drivable vehicle for resale.

If you live far enough north in cold enough winter you will want to bring the battery pack into the garage while the EV is up on blocks in the side yard waiting on sheet metal and lower control arms. headlights, paint.

Turn a couple of those over and you will eventually be able to buy something "hit hard T-bone" outright, keep the batteries and sell parts off the most recent EV to someone else working their way up the battery food chain.

My opinion, if it hasn't been done already, even with a mild to moderate recession, it will be less than 3 years for someone somewhere to put the batt and running gear out of a wrecked Tesla Plaid into a Leaf or Prius or similar. This tech is here to stay, it is advancing rapidly, and it is on the cusp of affordability.

The one thing I would not do right now is dump a bunch of $$ into a proprietary system. Solar panels put out watts, volts x amps. Batteries store watts as ampere hours at specified output voltages. If you find a great deal on flooded lead acid batteries, great. If you find a great deal on a Tesla wall doohickey, great.

The one place I have no plans to scrimp is on the inverters. A high end inverter now is going to be respectable for a while. If you end up with cheap batteries now and cheap panels now with good inverter technology you can upgrade the panels and the batteries as deals come along and your inverters should last quite a few years. An inverter is essentially an AC-DC-AC converter straight out of an amplifier circuit, sometimes run in reverse and sometimes run partially, but we as a species have putting those in semiconductors for decades and running them analog for a really really long time. I am NOT saying there is no room for improvement in inverters, but it is relatively mature tech compared to batteries and solar panels.

I do agree switching out panels can be a lot of labor $. I am not looking, short term, for huge changes in solar panel or inverter technology, the short term changes are going to be in battery tech. Exactly why I personally would not sink a lot of money into a battery right now.

 

[EbS-P]

If one could get a ford lighting delivered in reasonable timeframe that would be my best solution. Of course you would need to install the 80 amp charging circuit. From a price perspective it was cheaper than a power wall and you could drive it! Ford is marketing this. Others will follow.

I’m not sold on large batteries for the home yet. I think we are right at that point in the market that change will be happening fast.

I would be interested in a smaller off grid setup maybe 4-6 panels with 4-7 kWh of batteries as a DIY project . Tied to a mini split and and available to a few other appliances should the grid go down. Check out DIY Solar channel on YouTube for ideas.

If I already had solar and a half decent net metering contract for at least 10 more years. I’d probably invest in a decent manual transfer switch, and see if I could add solar capacity. Really just a couple big batteries 12v even charger and a big inverter built into a nice sturdy wheeled box would be great.

 

[Brian26]

It looks like NJ is working on a battery incentive so I would wait it out and see as there are none right now. Something similair like Eversource's really good incentive in New England may be available next year in NJ

https://www.google.com/amp/s/www.njspotlightnews.org/2022/06/nj-energy-environment-legislation-storage-systems-subsidies-incentives-offshore-solar-power/amp/

Eversource in New England is running a pretty good program in Massachusetts and Connecticut where they pay you to draw from your battery during high demand. I think I read the math works out where Eversource would basically pay for your battery in 5 years and then its yours. You can then opt out of the program after 5 and with a 10 year warranty on a powerwall you can get another 5 years from the battery.

Here is the current incentive from Eversource. I'm on solar and have been looking into this program as the incentive is one of the best in the nation for battery storage.

The incentive paid to you depends on three factors 1) the incentive rate, 2) the average kW your battery contributes and 3) what, if any, portion of the incentive your battery installer or manufacturer collects in return for managing your participation. The current incentive rate is $225/kW. Please consult your battery installer or manufacturer for your battery’s expected contribution and information about what, if any, portion of the incentive they collect.

Home Battery Storage FAQs | Eversource

Find answers to common questions about the Eversource ConnectedSolutions Battery Storage Demand Response program.

www.eversource.com

 

[begreen]

Has anyone looked into LG solar battery ? It looks price competitive with the Tesla wall.

LG Solar Batteries Expert Review: Which One is Right For Your Home?

LG solar batteries can power your home in an outage and store excess energy from solar panels. Are they the best choice for your home?

www.solarreviews.com

I notice a developing crop of portable battery packs that are growing in size and capability. This one can be generator, grid, or solar charged.

BLUETTI EP500Pro Solar Power Station | 3,000W 5,120Wh

BLUETTI EP500Pro, a 3,000W/5,100Wh off-grid monster, is sure to give you comfort knowing when the power goes out.

www.bluettipower.com

 

[peakbagger]

Has anyone looked into LG solar battery ? It looks price competitive with the Tesla wall.

LG Solar Batteries Expert Review: Which One is Right For Your Home?

LG solar batteries can power your home in an outage and store excess energy from solar panels. Are they the best choice for your home?

www.solarreviews.com

I notice a developing crop of portable battery packs that are growing in size and capability. This one can be generator, grid, or solar charged.

BLUETTI EP500Pro Solar Power Station | 3,000W 5,120Wh

BLUETTI EP500Pro, a 3,000W/5,100Wh off-grid monster, is sure to give you comfort knowing when the power goes out.

www.bluettipower.com

LG Resu batteries had a big recall recently.

 

[woodgeek]

I heard about the LG home battery recall too. And of course, all the LG EV batteries made over the last several years were recalled too.

 

[Woodsplitter67]

This really is alot of good information.. Just as a heas up...I am reading this.. just thinking about options..

 

[Woodsplitter67]

To answer the above.. I have solaredge equipment..iinverters 2 of them

 

[Brian26]

Has anyone looked into LG solar battery ? It looks price competitive with the Tesla wall.

LG Solar Batteries Expert Review: Which One is Right For Your Home?

LG solar batteries can power your home in an outage and store excess energy from solar panels. Are they the best choice for your home?

www.solarreviews.com

I notice a developing crop of portable battery packs that are growing in size and capability. This one can be generator, grid, or solar charged.

BLUETTI EP500Pro Solar Power Station | 3,000W 5,120Wh

BLUETTI EP500Pro, a 3,000W/5,100Wh off-grid monster, is sure to give you comfort knowing when the power goes out.

www.bluettipower.com

I picked up the Bluetti Eb3a and posted about it the solar generator thread. Their larger units look really nice and I bought their basic starter model to learn about these style units with the hopes of buying a larger one.

What's really big with these unit is it they have a built in solar MPTT controller and can do pass through with the solar. They can also be charged simultaneously with a generator and solar input at the same time. These units with lipo4 batteries can be recharged crazy fast as well. It says the max solar input is 2400 watts on that Bluetti and once the battery is charged it will just pass on that solar input on to the load side.

For $5k your not only getting 5100wh of battery storage which is a good price you also get a built in solar charge controller, ac inverter, and a battery management system all on wheels that only weighs 180lbs.

 

[begreen]

For $5k your not only getting 5100wh of battery storage which is a good price you also get a built in solar charge controller, ac inverter, and a battery management system all on wheels that only weighs 180lbs.

And an excellent UPS system too. I see that they can be ganged for single-phase 240vac output too.

 

[trx250r87]

I picked up the Bluetti Eb3a and posted about it the solar generator thread. Their larger units look really nice and I bought their basic starter model to learn about these style units with the hopes of buying a larger one.

What's really big with these unit is it they have a built in solar MPTT controller and can do pass through with the solar. They can also be charged simultaneously with a generator and solar input at the same time. These units with lipo4 batteries can be recharged crazy fast as well. It says the max solar input is 2400 watts on that Bluetti and once the battery is charged it will just pass on that solar input on to the load side.

For $5k your not only getting 5100wh of battery storage which is a good price you also get a built in solar charge controller, ac inverter, and a battery management system all on wheels that only weighs 180lbs.

I have been watching the technology recently as well. I like the Ecoflow brand option slightly better than the Bluetti. Ecoflow Delta Pro is pretty cool. They are modular, 3.6kWh up to 25kWh and have a gas generator add-on option as well.

Buy EcoFlow DELTA Pro Portable Power Station | EcoFlow

Official EcoFlow DELTA Pro: ✓ Capacity：3600Wh ✓ Battery Cell Type: ‎Lithium Ion (LFP). Click to learn more!

us.ecoflow.com

Eric

 

[peakbagger]

I would caution going with a proprietary system, its likely its not going to play well with other manufacturer's systems. There are a whole of companies in this space and not all of them are going to make it and when that happens someone ends up with lot of gear that may or may not keep working. SolarCity was installing proprietary inverters designed to plug into a high voltage Tesla Powerwall. Tesla stopped that Powerwall model so anyone with that inverter is out of luck. The inverter was built by Delta a big inverter company but Delta wont touch them as Tesla equipment was responsible for battery management.

 

[mellow]

I agree with the implied opinions of @peakbagger and @woodgeek that pretty soon the economical choice is going to be to buy a wrecked EV "hit light front" and work the batteries in it while you use the savings to buy parts to get the EV on the road again as a drivable vehicle for resale.

I was looking at doing this but man, even totaled tesla 3's are going for 15-17k! Light damage ones are 20k+. What are you seeing for prices?

 

[peakbagger]

I see a lot of used EV batteries for sale on Ebay. I am also active on solar forums where folks are reconfiguring the batteries into storage batteries. The basics sound simple but my understanding is the "devil is in the details". Unlike conventional battery chemistries, high energy density Lithium chemistry batteries have to be monitored individually and charging must be controlled at a cell level. The EV manufacturers have Battery Management Systems (BMS) but they are designed specific to the original EV battery design. There appears to be many third party BMS suppliers, but they do not appear to be plug and play with varying degrees of support and documentation. Get the BMS wrong and overcharge a cell and the resulting fire will set off adjoining cells.
Many of the automotive EV batteries have water cooling and heating which seems to be skipped when reconfigured. There are more than a few home built battery builders including some on Youtube who had large fires due to battery failures. There are various firms selling home brew batteries that purport to be designed and ready to go but good luck collecting anything if they fail. Easy to hide behind a LLC and Ebay listing.

I have seen a few firms that represent that they have "worked out" reconfiguring EV battery packs into home batteries but to date they seem to disappear when they are ready to go to the big time which implies to me they were not ready.

 

[begreen]

Used Leaf batteries seem popular for home battery packs. They did not have a built-in cooling system. There are even some companies selling them in backup battery packs.
And some are being used at scale.

Used Nissan Leaf batteries are already making money as power brokers

A California company is showing the template for whole used battery packs from Nissan Leaf EVs to be used as megawatt-hour grid storage.

www.greencarreports.com

This one is up in British Columbia

Top 26 Spotlight: Moment Energy - New Ventures BC

Moment Energy offers energy storage systems (ESS) ranging from 100kWh – 5MWh for ongrid and offgrid applications. Their systems are built using retired EV batteries and are equipped with a … Read more Top 26 Spotlight: Moment Energy

www.newventuresbc.com

Moment Energy - Clean, Affordable & Reliable Battery Energy Storage System

Moment Energy provides commercial-scale clean, affordable, and reliable energy storage by repurposing retired electric vehicle batteries.

www.momentenergy.com

 

[ABMax24]

I see a lot of used EV batteries for sale on Ebay. I am also active on solar forums where folks are reconfiguring the batteries into storage batteries. The basics sound simple but my understanding is the "devil is in the details". Unlike conventional battery chemistries, high energy density Lithium chemistry batteries have to be monitored individually and charging must be controlled at a cell level. The EV manufacturers have Battery Management Systems (BMS) but they are designed specific to the original EV battery design. There appears to be many third party BMS suppliers, but they do not appear to be plug and play with varying degrees of support and documentation. Get the BMS wrong and overcharge a cell and the resulting fire will set off adjoining cells.
Many of the automotive EV batteries have water cooling and heating which seems to be skipped when reconfigured. There are more than a few home built battery builders including some on Youtube who had large fires due to battery failures. There are various firms selling home brew batteries that purport to be designed and ready to go but good luck collecting anything if they fail. Easy to hide behind a LLC and Ebay listing.

I have seen a few firms that represent that they have "worked out" reconfiguring EV battery packs into home batteries but to date they seem to disappear when they are ready to go to the big time which implies to me they were not ready.

I've followed a few people that went off-grid with lithium ion and the common principle seems to be to setup the inverters, charge controllers, batteries and backup generator in there own seperate building some distance from the house. Keeping all the "fire prone" equipment away from the house in case of fire. Much like some do with wood boilers.

I guess it also protects the expensive power equipment in the event of a house fire.

 

[Poindexter]

I was looking at doing this but man, even totaled tesla 3's are going for 15-17k! Light damage ones are 20k+. What are you seeing for prices?

I am honestly not even looking at local hardware. We are hoping to list and sell the current house in Feb 2023 and buy something with the wood stove on the ground level also in Feb 2023.

In the meantime, I will be carrying 6-8 cords of wood upstairs this winter, again.

I like the idea of a usable EV that can serve as a whole house battery during outages. But it would be tricky, with the wife and I both working, to leave a perfectly good vehicle at home during the day while it is getting solar charged. If you can charge an EV at work and come home with an 75-90% charge it would make a lot more sense.

OP is down in the lower 48. Up here we will likely stick with ICE vehicles for quite a little while for year round/ wintertime use. For me a standalone household battery pack for use during outages would be a reliability upgrade from selling my (future) solar output to the grid.