Powerwall from Green Mountain Power

[Ben25]

Looks like I'm going to be getting a Powerwall as soon as I can. At $37.50 a month, I should be able to cover the price with my solar credits. It will be interesting to see how they tie it in with my existing 10k Solaredge inverter.

Ben

[SunEagle]

Looks like I'm going to be getting a Powerwall as soon as I can. At $37.50 a month, I should be able to cover the price with my solar credits. It will be interesting to see how they tie it in with my existing 10k Solaredge inverter.

Ben

Cool. Let us know how it works whenever Tesla get around to building the thing.

[deyounte]

Looks like I'm going to be getting a Powerwall as soon as I can. At $37.50 a month, I should be able to cover the price with my solar credits. It will be interesting to see how they tie it in with my existing 10k Solaredge inverter.

Ben

For a grid tied system is there any reason to have batteries other than as a backup system? Or is this for off grid?

Tim D.
Melbourne, FL

[Ben25]

Nope. Not unless you're using it for peak shaving. I just hate having all that available power on the roof and not being able to use any of it when the grid is down. I could get a generator, and it may be cheaper in the long run, but we'll see.

[peakbagger]

I just love Vermont, plucking money out of one ratepayers pocket through the Efficiency Vermont surcharge to fund someone else's backup system. Dont feel guilty, just take it if they offer it.

Then again in VT much of the rural part of the state is borderline third world for an electrical grid so power outages are far more frequent. This is not a attack on it, there was just a long term decision over the years to underfund grid improvements and minimize right of way clearing in many areas. It keeps the rural character but sure raises havoc during unusual weather.

[Living Large]

Then again in VT much of the rural part of the state is borderline third world for an electrical grid so power outages are far more frequent. This is not a attack on it, there was just a long term decision over the years to underfund grid improvements and minimize right of way clearing in many areas. It keeps the rural character but sure raises havoc during unusual weather.

Where my brother lives, not far from where I am moving to in the lower Adirondacks, the power goes out frequently for short periods, and he recently told me many are announced before hand via phone blast. Not sure what that is about, and I'm hoping it won't happen where I am. He's out where you wink at deer, hoping for a date.

[jflorey2]

Nope. Not unless you're using it for peak shaving. I just hate having all that available power on the roof and not being able to use any of it when the grid is down.

You could always do a conventional hybrid system or use an SMA TL-US string inverter. The TL-US will give you 1500 watts of backup with no battery costs.

[Ben25]

It's a little late for that, I have a Solaredge system already. Plus, odds are when you actually need power from the secure power supply, it will be dark or the panels will be covered in snow...

[emartin00]

$37.50 per month is a lot of money for a backup source that you MIGHT use. You will eclipse the cost of a backup generator in less than a year.

[Ben25]

It would be a lot if I were actually paying for it. I'm overproducing enough that I should cover the entire cost with my credits.

[SunEagle]

Ben

That is sort of false economy. If you are getting credits for your over production, unless you end up losing those credits at the end of the year, IMO spending them on anything is not saving anything. Why is that extra money from your credits "burning a hole in your pocket"?

[J.P.M.]

It would be a lot if I were actually paying for it. I'm overproducing enough that I should cover the entire cost with my credits.

Depends on a lot of things, one of which is how much you are compensated for excess generation. Your money, your choice, but if you're backing into an after the fact justification for oversizing an array, the way most POCOs pay for excess, it's still a lousy return, regardless of the use of the revenue. SREC's may modify that a bit however.

[Ben25]

We get $0.207/kWh and pay $0.147. Yes, the system was oversized, but I paid about $.95/w after tax credits. There is also nothing saying that I can't oversize. The credits do expire after a year, so yes, they are burning a hole in my pocket. I agree that it is a lousy return though.

[SunEagle]

We get $0.207/kWh and pay $0.147. Yes, the system was oversized, but I paid about $.95/w after tax credits. There is also nothing saying that I can't oversize. The credits do expire after a year, so yes, they are burning a hole in my pocket. I agree that it is a lousy return though.

I agree it may be better to use those credits before you lose them but for an untested (and expensive) battery system seems like throwing away money.

But as others have said, it is your money and your choice.

[radareclipse]

We get $0.207/kWh and pay $0.147. Yes, the system was oversized, but I paid about $.95/w after tax credits. There is also nothing saying that I can't oversize. The credits do expire after a year, so yes, they are burning a hole in my pocket. I agree that it is a lousy return though.

You are receiving more than you pay out? Usually they credit you at wholesale rates.

That PowerWall seemed like it would be good for a few short hours in an evening when I was checking out the earliest information.