Vermont Battery Program - open to all

[peakbagger]

Vermont regulators lift cap on Green Mountain Power home battery programs

Green Mountain Power says more people signed up for the batteries, which are able to store power and provide energy during extreme weather events, after this summer's floods.

www.vermontpublic.org

Certain utilities in VT have offered customers the option of leasing a home battery for a couple of year under pilot program but the state now taken the limits off the number of customers who can get the program plus added a bring your own battery option (meaning non powerwall). The big selling point is that when the power goes out, the homeowner can run off the battery for some limited period of time. Vermont has notoriously unreliable power in rural areas so power outages especially in the winter are frequent so having some standby power is handy. The customer gets various benefits for renting a battery and more importantly in exchange for those benefits, the utility gets the right to "borrow" the batteries capacity to deal with short term grid events. In the event of major transmission systems loss, getting backup power for the first 5 minutes is quite expensive so having the option of being able to discharge local home batteries back into the grid for a short period means that expensive 5 minute power will be needed in lesser amounts. In the event of localized power sags, the batteries can be dispatched to boost up the grid.

The trade off is if the weather is stormy and the power if going on and off, the utility may borrow some power from the home battery to support the grid and then when the power goes out, the homeowner is left with a nearly empty battery. This is not theoretical, there have already been incidences where the batteries were mostly drained before the grid power finally went out.

There is a reserve on the battery but its reportedly quite low so the person paying the extra money on their bill quickly see the power go out. It works fine if its an unusual grid event like a car running into a pole or transmission and distribution issue but not so good for wind and rain events.

As far as I am concerned, it makes more sense to have an electric car in the driveway with a B2G connection rather than a dedicated battery but if folks want to pay to be guinea pigs to have another battery in the house, more power to them. My guess is the majority of folks in the program are in it for bragging rights.

 

[Ashful]

This is not theoretical, there have already been incidences where the batteries were mostly drained before the grid power finally went out.

It seems likely that those batteries were what allows you to use the word "finally" in this sentence, the collection of home batteries on your side of the switchgear being what kept the grid up for some period after some more distant failure in the transmission path. Right?

I can see why the customers who went to the trouble and expense (even if mostly subsidized) to install these batteries, while their neighbors did not, would feel used.

As far as I am concerned, it makes more sense to have an electric car in the driveway with a B2G connection rather than a dedicated battery but if folks want to pay to be guinea pigs to have another battery in the house, more power to them. My guess is the majority of folks in the program are in it for bragging rights.

Agreed. I also think that as BEV's become more ubiquitous, this is going to become seen more and more as one of their primary advantages. This can't be good for Generac, and others trying to convince potential new customers to invest in a home generator, excepting those with regular very long outages. Most of our outages are under an hour, which I imagine a BEV is going to carry without any change in behavior or demand.

 

[woodgeek]

Agreed. I also think that as BEV's become more ubiquitous, this is going to become seen more and more as one of their primary advantages. This can't be good for Generac, and others trying to convince potential new customers to invest in a home generator, excepting those with regular very long outages. Most of our outages are under an hour, which I imagine a BEV is going to carry without any change in behavior or demand.

Indeed. As someone who has been backfeeding his house from an EV since 2016, including a 13 hour run last month after a tornado blew through town. The only issue is that I have no way to tell when the grid has been restored, except listening for when my neighbors' gennies shut off.

 

[Ashful]

...I have no way to tell when the grid has been restored, except listening for when my neighbors' gennies shut off.

I had the same problem, as I backfeed from a portable generator with main breaker turned off. Then one day I realized the digital meter mounted right outside my front door was a great indicator of when power comes back on. I just check it once per hour, and when I see it has gone back online, I shut off my generator and switch back over to the mains.

This won't work with an older analog meter, unless it has some indicator light on it, as the platter won't spin until you apply a load. But the digital meters usually have an LCD that goes dead when grid is down, and re-lights when it comes back online.

 

[EbS-P]

Car battery to grid is the most logical for the owner but less reliable (must be plugged in and charged) for the utility. Seems to me that a major auto maker needs start a utility company division. All the networking hardware is in place in the vehicle. Owners could get a deal on a charger.

 

[blades]

Why would you , as I gather reading this, want to subsidies the power company by buying into this on a monthly basis and when you need it the power co sucks it dry. big win power co. , consumer seems to get the elevator shaft. A propane powered genny can sit for ever but is there when you need it ( or NG if that is avaiable as that is seldom affected by mother nature although as of late a propane tank looks more viable). You do not need to go as far as the generac solution plenty of portable gennies around up 9000 watts, if you are on a well that pump would likely be your highest draw, a 4000w or smaller gennie can supple more than enough for all other uses ( not counting electric stove or dryer)

 

[begreen]

I also backfeed after disconnecting from the grid. If I were to put in a battery backup system my preference would be to island our house and solar systems with a Sunny Island inverter setup. That's unlikely now given the ROI, but I had considered this when we set up the solar. Instead, I opted for a propane generator that covers refrigeration and some lights + the car's battery for redundancy. Fortunately, the power company has been proactive about tree trimming near power lines so outages >24hrs have become rarer.

 

[woodgeek]

Why would you , as I gather reading this, want to subsidies the power company by buying into this on a monthly basis and when you need it the power co sucks it dry. big win power co. , consumer seems to get the elevator shaft. A propane powered genny can sit for ever but is there when you need it ( or NG if that is avaiable as that is seldom affected by mother nature although as of late a propane tank looks more viable). You do not need to go as far as the generac solution plenty of portable gennies around up 9000 watts, if you are on a well that pump would likely be your highest draw, a 4000w or smaller gennie can supple more than enough for all other uses ( not counting electric stove or dryer)

I agree with you that if the power co keeps the battery at 20% SOC or less, this is a BS deal. But it seems that they can get grid stabilization and still guarantee not taking the SOC below 50%. If that pays enough for the consumer to get a huge discount, then its win-win.

Not that PA is going to offer any such thing anytime soon, sitting on a pile of cheap nat gas.

That said, running your house on a battery is sweet, esp when it is stormy out and the battery is in your warm attached garage.

Ofc, I have city water and sewer, and am happy with ~1600W max backfeeding my 120V loads.

 

[Ashful]

Ofc, I have city water and sewer, and am happy with ~1600W max backfeeding my 120V loads.

Our well is our single largest draw, when running the generator. You really hear the thing bog when the well pump kicks on.

 

[EbS-P]

My in-laws just got a 14kw generac installed last fall. They told them not to use the oven/range. It’s oil heat with a well. No transfer panel.

 

[Ashful]

My in-laws just got a 14kw generac installed last fall. They told them not to use the oven/range. It’s oil heat with a well. No transfer panel.

Basically what I have here, except the "transfer panel" is me, running between basement and garage in my slippers.

 

[spuldup]

I had the same problem, as I backfeed from a portable generator with main breaker turned off. Then one day I realized the digital meter mounted right outside my front door was a great indicator of when power comes back on. I just check it once per hour, and when I see it has gone back online, I shut off my generator and switch back over to the mains.

This won't work with an older analog meter, unless it has some indicator light on it, as the platter won't spin until you apply a load. But the digital meters usually have an LCD that goes dead when grid is down, and re-lights when it comes back online.

This is a great idea that I will use next time we are on the genny. Thanks!

 

[woodgeek]

This is a great idea that I will use next time we are on the genny. Thanks!

For me, I have the advantage I can hear my two neighbors gennies from inside my house, but would have to walk outside to look for the indicator light....

 

[semipro]

Indeed. As someone who has been backfeeding his house from an EV since 2016, including a 13 hour run last month after a tornado blew through town. The only issue is that I have no way to tell when the grid has been restored, except listening for when my neighbors' gennies shut off.

Funny, I hear my neighbor's whole-house generator when it lights up monthly but never thought of using it to indicate a grid outage.
I bought a neon indicator lamp with the intent of installing it across my mains above the breaker so I could tell when the power goes out -- yet another project unfinished.
Our inverter cuts in in something like 1/20th of a second so we'll miss it if not looking for it.

 

[mellow]

I had read about this program when I was looking into getting tesla solar+powerwall a few years back. I would have not opted in for someone else using my battery storage which would have eliminated the subsidy. Rolls battery was the solution I would have gone with but ended up spending the money on outfitting my camper with better batteries.

Not an exact solution but my Truck Camper is setup to be off grid for days, I have a propane generator on it and solar so during a prolonged outage I would just live in it. We usually camp on the beach for a couple days at a time so the family is used to conserving water and electric during the night. If needed I could just run the AC off the genny or heat off propane.