Battery Backup?

[shazam]

It's hard to believe we've had our MEP803 in place for 4 years already. In spite of the fact it's only been used in earnest twice, we're happy with the investment. It's hard-wired to the main 200 amp breaker panel thru an 80 amp breaker and an either/or power lock-out on the main/gen breakers. Manual (remote) start from a switch near the main panel.

For reference, the long-term plan.....add solar/wind and hopefully ditch the power company. We have ideally located for both (such as they are in Ohio) on a hill 36-feet above terrain, with a 2-mile upslope, surrounded by crops and no trees, and with a south-facing roof. We're in a small energy-efficient ICF house, and the 803 will run the whole place (including heat pump summer and winter) without breaking a sweat.

Now on to stage two...

Considering that perhaps the next phase should be battery back-up for the generator, both to modulate the excessive gennie production during current outages and maintenance runs, and to prepare for integrating the renewable energy sources.

Now, the question of the moment....and I come seeking wisdom. Is anyone currently using a battery-backup solution in connection with their gennies, or explored it in depth? Options seem to be flooded cells, lithium, or the whole-house batteries (offered from several manufacturers).

BTW....The little displays on the aux box in the pic show left/right amperage draw and running voltage when the gen is running.

Thanks in advance for your input!

Jim

 

[kloppk]

I'd strongly suggest using LIFEPO4 batteries and not lead acid.

I've run my solar panels, charge controller and inverter for over 7 years now and am on my 3rd battery bank.
First battery bank was comprised of 12v flood acid batteries in 48 volt configuration. Lasted about 2 years.
Second battery bank was 6V golf cart batteries in 48 volt configuration. Lasted about 2 years.
Both lead acid battery banks were a major PITA to need to constantly add water, keep corrosion in check, ventilate hydrogen gas away, equalize, check hydrometer readings, sulphation, .....

Bit the bullet a couple of years ago and bought 300AH 12 volt LIFEPO4 batteries. I could not be happier with them! Zero maintenance!

Lead acid batteries are about 85% efficient.
Should only be discharge to 50%, even less if you want to eek a bit more life out of them.
Low cycle life of ~ 1,500 cycles even if only discharged 50%
Produce lots of explosive hydrogen gas when charging and even more when equalizing
Batteries are HEAVY & large

AGM's eliminate the corrosion and watering issues but suffer discharge limit, cycle life, and efficiency like flooded and are pricier.

LIFEPO4 battery efficiency is in the high 90's
Can be discharge 80% and still have 5,000 cycles of life or more.
Can be discharged to 100% without harming. Cycle life is about 2,000 cycles if constantly fully discharged.
Output voltage is nearly constant from 100% charge to 0%
Batteries are surprisingly light weight for their capacity.
Generally using LIFEPO4 batteries you will only need about half the battery capacity you'd need lead acid since they can safely be discharged much further.

Downside is LIFEPO4 are pricey. But in my experience well worth it.

 

[rtrask]

The batteries will be your main expense. LIFEPO4 batteries are the way to go but as noted expensive. Look at it as a long term investment.

Start by understanding what your energy needs are. Analyze your bills and look at the months where your electricity usage was highest and figure out what your average KW Hour usage per day is. Then you should likely double that so that you have 2 days worth of storage. There are also usage calculators on the web where you enter all of the electrical appliances that you have and approximate usage and the tool will estimate your needs. It is probably a good idea to do both and compare them to make sure they are reasonably close to each other (the lower within 70% of the higher 1 day usage). If they are way off check your figures. Then find batteries that will meet your needs. I got mine from Big Battery dot com. You will also need a charge controller / inverter which is not cheap either. Get a 48 volt system.

Personally I think you should start with Solar panels and a charge controller / inverter and start selling excess production back to the power company.

 

[shazam]

Thanks for the responses!...great information! You've confirmed LiPo as the way to go.

We're doing the due diligence on energy needs, and between a monthly (since move-in) consumption graph from the utility cooperative, and the little 'Killawatts" are getting a handle on it.

The grid-tie vs. off-grid thing is an unresolved quandry at this point. The factors mitigating against grid-tie are basically related to the electric coop. There are 'looser' requirements in Ohio for them versus a 'normal' power company. Thus their $1K 'entry fee' (disguised as a site survey and $650 meter swap) to attach the solar. They also are considerably apart in what they charge for a KWh vs. pay.

The reliability of the 803 is leading me to considering that in lieu the 'power company'. I wouldn't trust many other generators in that regard.

Basically, contemplating setting up solar/wind/battery to 'run' the place most of the time, with an auto-cut-in of the 803 to charge the battery bank when it inevitably gets low. Will it be cheap...nope!...but there would be some satisfaction in it!.

Thanks!
Jim

 

[Mullaney]

Thanks for the responses!...great information! You've confirmed LiPo as the way to go.

We're doing the due diligence on energy needs, and between a monthly (since move-in) consumption graph from the utility cooperative, and the little 'Killawatts" are getting a handle on it.

The grid-tie vs. off-grid thing is an unresolved quandry at this point. The factors mitigating against grid-tie are basically related to the electric coop. There are 'looser' requirements in Ohio for them versus a 'normal' power company. Thus their $1K 'entry fee' (disguised as a site survey and $650 meter swap) to attach the solar. They also are considerably apart in what they charge for a KWh vs. pay.

The reliability of the 803 is leading me to considering that in lieu the 'power company'. I wouldn't trust many other generators in that regard.

Basically, contemplating setting up solar/wind/battery to 'run' the place most of the time, with an auto-cut-in of the 803 to charge the battery bank when it inevitably gets low. Will it be cheap...nope!...but there would be some satisfaction in it!.

Thanks!
Jim

.
And the fun part is that the Power Company pays you much less so they can make a profit on your generated power. They also don't pay maintenance on your equipment or replace your batteries when they get old and tired.

Just like the captive audience that the utility companies have had for years - they are going to make a profit. Guaranteed profit...

 

[shazam]

^^^^^ ....and that just annoys me

I'm admittedly a rank amateur. How would one run the massive output of the 803 into the battery bank?...is that the charge controller/ inverter function?

PS- I'm doing my on-line research, but been-there, done-that has it's advantages. I appreciate your indulgence.

 

[Weldman]

I'd strongly suggest using LIFEPO4 batteries and not lead acid.

I've run my solar panels, charge controller and inverter for over 7 years now and am on my 3rd battery bank.
First battery bank was comprised of 12v flood acid batteries in 48 volt configuration. Lasted about 2 years.
Second battery bank was 6V golf cart batteries in 48 volt configuration. Lasted about 2 years.
Both lead acid battery banks were a major PITA to need to constantly add water, keep corrosion in check, ventilate hydrogen gas away, equalize, check hydrometer readings, sulphation, .....

Bit the bullet a couple of years ago and bought 300AH 12 volt LIFEPO4 batteries. I could not be happier with them! Zero maintenance!

Lead acid batteries are about 85% efficient.
Should only be discharge to 50%, even less if you want to eek a bit more life out of them.
Low cycle life of ~ 1,500 cycles even if only discharged 50%
Produce lots of explosive hydrogen gas when charging and even more when equalizing
Batteries are HEAVY & large

AGM's eliminate the corrosion and watering issues but suffer discharge limit, cycle life, and efficiency like flooded and are pricier.

LIFEPO4 battery efficiency is in the high 90's
Can be discharge 80% and still have 5,000 cycles of life or more.
Can be discharged to 100% without harming. Cycle life is about 2,000 cycles if constantly fully discharged.
Output voltage is nearly constant from 100% charge to 0%
Batteries are surprisingly light weight for their capacity.
Generally using LIFEPO4 batteries you will only need about half the battery capacity you'd need lead acid since they can safely be discharged much further.

Downside is LIFEPO4 are pricey. But in my experience well worth it.

Down side to LiFePO4 is they can only be charged in temperatures over 32 degrees Fahrenheit, so if this is going to be in a cold area that freezes or worse I would avoid them.
Problem with your FLA batteries is the ones you got, a 12V will have thinnest lead plates and as you go lower in voltage per battery the thicker the plates. You could of gotten 10 plus years out of a 2V in a 48V configuration that would go neck to neck with a LiFePO4 on longevity.
Did you build your own LiFePO4 battery bank? Another thing with LiFePo4 is you need to monitor to make sure the cells stay balanced, don't always trust the BMS "Battery Management System"
I too have been off grid for quiet a few years (5) and only on one battery bank so far since it's a forklift battery.

 

[kloppk]

An inverter charger can do it.

The LIFEP04 batteries I have now each have an internal BMS. I use an external balancer to keep the batteries balanced.

LIFEP04 are available that have internal heaters so that the batteries can be used in subfreezing environments. Mine are in the basement so I didn't need ones with the heaters.

 

[shazam]

Thanks again for the info! I'm reading up on inverter chargers (among other things

This place rocks!

Jim

 

[kayak1]

You might look at SOL-ARK inverters, they are able to be run without batteries and add batteries later. They have inputs for grid and generators. With Kurt's 802/803 controller board you can setup the SOL-ARK to auto start your 803 when the grid is out.

I believe you can setup the Sol-Ark to not export, and just cover your internal loads, thus you wouldn't need the site review and new meter as you figure things out.


The Sol-Ark has some advantages over my Outback gs8048a in that it is able to communicate with the BMS of lithium batteries, it's a lot lighter, has everything built into one box, and can be run without batteries. The Outback is able to better deal with phases being out of balance and peak loads. The upside is also that all of the parts are separate thus, if one part breaks, you aren't replacing everything, and you can connect the Outback using a real ethernet cable and aren't depending on WIFI and hoping that the devices WIFi can be updated to handle the standard of the day along with the security of the day.

 

[rtrask]

One thing I forgot to say is avoid the temptation to build a Frankenstein system, buy sufficient batteries to meet your current and foreseeable future needs. Batteries perform best when they are matched, I think a rule of thumb is that your batteries are only as good as your weakest link. Battery technology is changing fast, and you may not be able to find another like the one you previously bought next year. Not saying you should oversize it, but better a little bit of extra capacity now. Solar panels are a little more forgiving, but don't mix panels with different voltages on the same string.

Also, the 803 is a great generator, but will the cost of diesel your aim should be to use it sparingly.

I am still building my house, I have 30 KWatts of battery, and I intend to use my 803 only for special projects like welding, or if I get equipment that runs on 3 phase. It gives me a lot of flexibility. The REA wanted $30,000.00 just to run the wire out to my property. It made the Grid / Off Grid decision pretty easy.

I have plenty of wind, and I may will likely look into some small wind turbines, but I am afraid of the maintenance on them. To start I am going to get sufficient PV panels

 

[shazam]

I feel like I'm swimming way over my head, but at least treading water!! Reading the info on the Sol-Ark site...thanks!

I concur, rtrask....diesel for the 803 would be a painful last resort, but even now is extremely comfortable to have in the mix!

So...sitting here minding my own business, watching something on TV...they're talking about solar...and the better half says she thinks we should pay the piper and hook up to sell solar/wind (neither of which we have yet, remember) back to the power company!!! Holy moly...this could really happen!!!

Jim

 

[DieselAddict]

Grid-tied wthout battery is the least cost way to get into solar for sure. A few things to consider is with most grid-tie setups you have little to no solar power available during a utility outage. You'll still be running on generator backup during an outage.

In my case I'm not going to install a system that exports power due to the Utilities requirement that the equipment owner not have access to the programming parameters of the system. I understand why they want that but its not acceptable to me. This becomes more important when you have batteries involved. In the case here the Utility would have the ability to shut my system down remotely and there would be nothing I could do about it. Again, unacceptable to me personally.

Be sure to fully understand the devil when entering an agreement with them. Don't let them pull the plug on your system remotely when you need it most.

Lastly, with SolArk, be sure to do some research and know fully what you are getting before you purchase. They have lots of nice features for sure but robust power output abilities ain't one of them. Be sure it will work for your needs especially if you have a good sized well pump or AC unit.

 

[shazam]

Thanks for the heads-up Chris! In addition to the power company having hooks into the software in my house, I'm concerned about inverter/etc manufacturers doing the same.

Case in point from previous experience...many consumer-grade security cameras go thru 'company' servers to provide their services. When I re-did my cams, I eliminated all that by limiting the cams/equipment/software connection to LAN only. They are free to 'talk' quietly among themselves, but not to anyone else. I use a VPN internal to my router to come in and monitor when away. (I'm a retired computer geek by the way) To me, this would be the ideal for a solar/wind system also. One of the beautiful things about the 803 is it doesn't 'phone home' to anyone.

Jim

 

[DieselAddict]

I have Schneider/Xantrex equipment that handle inverting and charge management. I also have their system integration gateway. You can subscribe to optional services for cloud monitoring and management. The gateway is a self contained management and data recording tool. You can easily block the system from the outside world via router rules or via your private VPN, manage it remotely via a web browser.

I can monitor my system or change any of the programming in the charge controller or inverter from anywhere I can reach my home IP address. No cloud service required.

For full transparency, I'm 100% anti cloud services. Wherever possible, my data stays on my systems.

 

[shazam]

For full transparency, I'm 100% anti cloud services. Wherever possible, my data stays on my systems.

Agree 100%!!!

 

[kayak1]

Thanks for the heads-up Chris! In addition to the power company having hooks into the software in my house, I'm concerned about inverter/etc manufacturers doing the same.

Case in point from previous experience...many consumer-grade security cameras go thru 'company' servers to provide their services. When I re-did my cams, I eliminated all that by limiting the cams/equipment/software connection to LAN only. They are free to 'talk' quietly among themselves, but not to anyone else. I use a VPN internal to my router to come in and monitor when away. (I'm a retired computer geek by the way) To me, this would be the ideal for a solar/wind system also. One of the beautiful things about the 803 is it doesn't 'phone home' to anyone.

Jim

Outbacks equipment was built as a standalone setup and the Internet part was added much later. I have seen a few systems when the installers walk away from them the passwords haven't been changed from the default and in any state other than CA nothing requires you to plug the ethernet connection in (CA requires this extra part: https://www.outbackpower.com/products/system-management/csip-bridge).

I really like my outback system but it has real transformers the shipping weight for the inverter, breaker box, two charge controllers, and the mate3 (used to program/monitor) all mounted on one panel is 280 pounds. It's a great system if you want rock-solid power. The internet monitoring has gotten a lot better (you don't need to use it if you don't want it). It hasn't kept up with the times in terms of adding things like load shifting, time of use, adding CT's at the panel entrance to zero out your full house energy etc.. It's solid and reliable like your 803.

Solar ARK is much more modern and will let you start off in a grid-tie setup and move to batteries when you have a better feel of things and was built and designed in a time when lithium batteries were the norm. It doesn't have the transformers that the Outback system does thus you are attempting to do a lot more with chips instead.

When you want to add batteries, matching batteries are required, and never undersize them.

 

[rtrask]

I use a VPN internal to my router to come in and monitor when away. (I'm a retired computer geek by the way) To me, this would be the ideal for a solar/wind system also. One of the beautiful things about the 803 is it doesn't 'phone home' to anyone.

Jim

I am an active computer computer geek, and can't retire yet (poor financial planning). Skirting the politics of the whole COVID mess, the one good thing that came out of it is it's now acceptable to work remotely, which is allowing me to do just that (I am about as remote as you can get). In February after being on the early adopter list for a year, I got Starlink coverage in my area. I have been really happy with the up/down bandwidth and latency. It's actually 50% better upload than the ADSL I had in Denver, and probably about 20 percent better than the download.

The unfortunate reality is that any system can be hacked, but doing what you have with the VPN will make it hard enough to not make it worth their while to do it.

 

[Mullaney]

I am an active computer computer geek, and can't retire yet (poor financial planning). Skirting the politics of the whole COVID mess, the one good thing that came out of it is it's now acceptable to work remotely, which is allowing me to do just that (I am about as remote as you can get). In February after being on the early adopter list for a year, I got Starlink coverage in my area. I have been really happy with the up/down bandwidth and latency. It's actually 50% better upload than the ADSL I had in Denver, and probably about 20 percent better than the download.

The unfortunate reality is that any system can be hacked, but doing what you have with the VPN will make it hard enough to not make it worth their while to do it.

.
Yeah. Plenty of easy things to hack that doesn't take near the effort. Especially since there are lots of numbnuts that have no password on their wireless routers or have the default cable or dsl routers...

 

[rtrask]

Down side to LiFePO4 is they can only be charged in temperatures over 32 degrees Fahrenheit, so if this is going to be in a cold area that freezes or worse I would avoid them.
Problem with your FLA batteries is the ones you got, a 12V will have thinnest lead plates and as you go lower in voltage per battery the thicker the plates. You could of gotten 10 plus years out of a 2V in a 48V configuration that would go neck to neck with a LiFePO4 on longevity.
Did you build your own LiFePO4 battery bank? Another thing with LiFePo4 is you need to monitor to make sure the cells stay balanced, don't always trust the BMS "Battery Management System"
I too have been off grid for quiet a few years (5) and only on one battery bank so far since it's a forklift battery.

I know this is an old thread, but I can add some practical experience. As Weldman said LifePO4 batteries don't charge well when they are in below freezing temperatures. I live in a high mountain valley at 8000 feet. It gets and stays cold here from the end of November to late March it never got above freezing and was generally in the low teens at night. My batteries are located in a shipping container with no heat. To counteract the cold I took a tip from Will Prowse, and bought a RV tank heating pad that I taped to the battery, and then wrapped them in insulation. The BMS on the batteries indicated that the temperature stayed in the 60's and charging was not a problem.