Whole house battery backup system?

REWahoo

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Texas: No Country for Old Men
I'm looking for input/opinions:

Our electric co-op has a new pilot program offering to lease co-op members without solar panels (that's us) a whole house battery backup system. The offer is for a 10 year lease (early termination fee of up to $500) with no up front installation charge. I can lease one or two 25 kWh batteries at a cost of $37/mo per battery, including tax. The co-op owns and manages the batteries, handling all maintenance and warranty-related work.

Here's the catch: The batteries will be used to help support the grid when needed but will always reserve a minimum of 50% of the battery capacity for our use if we lose power. The co-op will also provide us with a monthly bill credit (currently set at a flat $40) to pay for the electricity to charge/recharge the batteries.

We live in a rural area in an all-electric home, no gas. When the power goes out we lose all services, even water. We experience two or three outages every year, generally lasting only a few hours, but have had longer outages. I have a portable generator which we have used to run a window a/c unit or portable heater if the outage was in the peak of the summer or winter. That involves running extension cords and always making sure I have fresh fuel for the generator, which is a bit of a pain. That's why this offer has caught my interest.

Some brief research says the cost to purchase an installed whole house battery system of that size would be $25,000 or more, something that doesn't come anywhere close to passing my cost/benefit threshold. But leasing a two battery system for $74/mo is tempting.

The co-op says they will lease only 20 batteries in this pilot program and I got my application in early so I'm on the list. I got a call Friday saying all the info and the photos I sent with my initial interest form look good, all that is remaining is for them to come out and get an in-person look next week, then sign the lease agreement.

Thoughts?
 
You could change your generator for a propane powered one, and get a few 20lb->30lb propane tanks or even a large propane tank (100 lb).
Since propane doesn't go bad like gas, it will be ready to hook up to the generator at all times.

You'd still have the extension cord issue.

As to the batteries, are they covering all the connections to your house, so it's an easy switch/automatic if needed ?
How far across the grid will you be supporting, and paying for electricity to charge the batteries while they are supporting the grid ? If the grid is large enough, there will always be a power failure somewhere. Could it actually cost you more than $40/mo just to support the grid ?
 
What is the net cost per month? I see a charge of $37/mo/battery and a flat $40/mo credit. For one battery, that is a net $3/mo credit. For two batteries, that is $34/mo. Am I reading this correctly?
 
If there were an outage would the co-op be able to access the batteries and draw on their 50%?
 
Do the batteries have a built in inverter to convert the DC to AC or does the lease include a standalone inverter in the price?
 
You could change your generator for a propane powered one, and get a few 20lb->30lb propane tanks or even a large propane tank (100 lb).
Since propane doesn't go bad like gas, it will be ready to hook up to the generator at all times.

You'd still have the extension cord issue.
If I went this route I'd get a large enough generator to work through an interconnect to power selected house circuits plus the well. That would get rid of the extension cords but would still require work on my part to test/maintain the generator, change out/fill propane tanks, etc. My guess is that would probably cost somewhere in the neighborhood of $3k for the generator, interlink installation, and propane tanks.
As to the batteries, are they covering all the connections to your house, so it's an easy switch/automatic if needed ?
Automatic connection to the whole house. I'd need to manually switch off the breakers to circuits I didn't want in order to make the battery last as long as possible.
How far across the grid will you be supporting, and paying for electricity to charge the batteries while they are supporting the grid ? If the grid is large enough, there will always be a power failure somewhere.
That question is best answered by Base, the company that is pioneering this battery lease/grid supply system in Texas. Here is a link: How batteries support the grid | Base Power
Could it actually cost you more than $40/mo just to support the grid ?
Not sure, but I was told that one of the purposes of the pilot was to determine the cost of the electricity to charge/recharge the batteries so that the homeowner could be credited for that amount. Our co-op is very tech savvy (they supply fiber internet service as well) and I expect them to be sure folks who opt for this program are given accurate bill credit.
 
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What is the net cost per month? I see a charge of $37/mo/battery and a flat $40/mo credit. For one battery, that is a net $3/mo credit. For two batteries, that is $34/mo. Am I reading this correctly?
Net cost for two batteries is $74 less $40 credit plus the unknown added cost to recharge the batteries. I'm expecting the credit will eventually become a variable amount equal to the actual monthly cost to charge the batteries.
 
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If there were an outage would the co-op be able to access the batteries and draw on their 50%?
No, they would have to draw down their 50% prior to any outage:
During an outage, the batteries automatically detect the loss of grid voltage and immediately disconnect your house from the grid. At that point, the battery supplies energy exclusively to your home—you are legally entitled to this energy, and our batteries will never discharge to the grid during an outage.
The following is a detailed explanation of how the system works. Base is the company that offers the system through my co-op: Understanding how Base charges and discharges its batteries | Base Power
 
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N

Net cost for two batteries is $74 less $40 credit plus the unknown added cost to recharge the batteries. I'm expecting the credit will eventually become a variable amount equal to the actual monthly cost to charge the batteries.
I bought a 9kW genset that runs on my natural gas connection. I had a sub panel installed for the genset and that cost another $3k. Since we use natural gas for the water heater, home heat and gas stove, that genset can run everything but the air conditioner and the electric dryer. For an all electric house, you would need a big genset to run the heat pump (compressor locked rotor amps are huge).

Just looked at their site and it shows an 11kW inverter. You would need at least a 15kW inverter to run a heat pump. And that is a smaller 3T heat pump. It looks like this is TX, so sure would be nice to have air conditioning when the power is out.
 
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N

Net cost for two batteries is $74 less $40 credit plus the unknown added cost to recharge the batteries. I'm expecting the credit will eventually become a variable amount equal to the actual monthly cost to charge the batteries.
You might expect something fair like that, but the contract may not allow that, even if it costs you twice that rate to pay for the power.

Are you able to cancel out and have them remove everything for free ? or is it a huge cancellation cost of thousands of dollars ?

<edit> I know you said cancellation fee of $500, but what about removal, I've seen rental contracts for appliances that had a cancellation fee, but that was just for the "account" , there was also a much higher removal fee.
 
You might expect something fair like that, but the contract may not allow that, even if it costs you twice that rate to pay for the power.

Are you able to cancel out and have them remove everything for free ? or is it a huge cancellation cost of thousands of dollars ?

<edit> I know you said cancellation fee of $500, but what about removal, I've seen rental contracts for appliances that had a cancellation fee, but that was just for the "account" , there was also a much higher removal fee.
Good point.

I haven't seen the actual lease agreement yet so I don't know the exact wording. However, I spent the last 15 years of my work life negotiating purchase contracts and have both the skills and inclination to understand it in fine detail before signing.
 
The nice thing about this is the $500 cancellation. Considering the high upfront costs paid by the co-op it’s really not much to pay and limits your downside.
 
I would prefer a system that I am in control of. I probably would install a generator interlock on my panel to eliminate extension cords and up the capacity of the generator.
Since you have an ev you could also install a 1-2 kw inverter on the car and use the car charge to provide some power too.
 
I bought a 9kW genset that runs on my natural gas connection. I had a sub panel installed for the genset and that cost another $3k. Since we use natural gas for the water heater, home heat and gas stove, that genset can run everything but the air conditioner and the electric dryer. For an all electric house, you would need a big genset to run the heat pump (compressor locked rotor amps are huge).

Just looked at their site and it shows an 11kW inverter. You would need at least a 15kW inverter to run a heat pump. And that is a smaller 3T heat pump. It looks like this is TX, so sure would be nice to have air conditioning when the power is out.
Yes, this is TX and "nice" is an understatement when it comes to describing the need for air conditioning. :)

We have a 4T heat pump and would not expect to run the central a/c system in the event of an outage. We have a 300+ sq ft former screened porch that we had converted to a play room for the grandkids many years ago. It has a PTAC unit that can heat/cool that room independent of the central air system. That's where we hang out when we lose power for more than a couple of hours.
 
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I would prefer a system that I am in control of. I probably would install a generator interlock on my panel to eliminate extension cords and up the capacity of the generator.
One factor I didn't mention is I'm not sure how long we will keep the house. We are 78/77 and in reasonably good health, but who knows what tomorrow will bring. For that reason I am reluctant to invest several thousand bucks in a good generator system that a prospective buyer may not value. I really like the idea of getting most of the same benefits with no upfront costs. Per MichaelB:
The nice thing about this is the $500 cancellation. Considering the high upfront costs paid by the co-op it’s really not much to pay and limits your downside.

Since you have an ev you could also install a 1-2 kw inverter on the car and use the car charge to provide some power too.
Yes, I have considered that but in essence that's just another extension cord or two I'd need to manage.

Bottom line: I'm old. I'm lazy. I'm looking for an out when it comes to power. (See what I did there? :)
 
Yes, this is TX and "nice" is an understatement when it comes to describing the need for air conditioning. :)

We have a 4T heat pump and would not expect to run the central a/c system in the event of an outage. We have a 300+ sq ft former screened porch that we had converted to a play room for the grandkids many years ago. It has a PTAC unit that can heat/cool that room independent of the central air system. That's where we hang out when we lose power for more than a couple of hours.
If that’s the case, I would jump on this setup. 50kWh is plenty and the install alone is worth it, IMHO. And they have to maintain it. I say go for it!
 
Sounds like a good deal to me, without digging into details. $37 a month to buy insurance against power outages. I think it would be a selling point if you decide to sell. With an easy out I’d lean to going for it. We very seldom have power outages, every 2-3 years, and only one that lasted hours in 17 years in this house, so I might not bite here.
I’d love to see how it turns out if you decide to accept the offer.
 
One thing that would be good about battery is those short blips that happen... from a few seconds to a few minutes... they happen here... you would not even notice them at all...

The other thing that I would want is to be able to charge the batteries if they run down with a generator... hook up your small one and run until the battery is full again and you can go a LONG time without grid power...

Our longest outage since I got my whole house generator was about 7 1/2 days... batteries would have died early on...

BTW, I would run my AC unit... the whole point of having a big back up power unit is to not change what you normally do...

Last thing... 10 year cost is under $9K... I will assume the $40 credit will be used so it is a wash... that is cheap IMO..
 
We are 78/77 and in reasonably good health, but who knows what tomorrow will bring. For that reason I am reluctant to invest several thousand bucks in a good generator system that a prospective buyer may not value.

We're the same age and have the same thoughts.

Currently all I have is a small gasoline powered generator and a one kw inverter I could power from the car for emergencies. Our power outages are infrequent and the only critical items to power in the house are the furnace blower and the sump pump. If we're home at the time of the outage and if we're up to running extension cords around, we'd be OK for a few days.

But, I'd really like something that would take over for the sump pump and furnace blower motor without our intervention in case we're travelling at the time of the outage. A natural gas automatic generator would be great but cost a lot. The situation you have with the leased batteries sounds like a great idea. I wish they'd offer something like that here!
 
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