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Powerwall in New England ?

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In Massachusetts, net metering is on both generation and distribution at 100% retail rates.
That depends on the utility. I have municipal utility and I only get wholesale generation rate. Nothing for distribution.

So, I have 2 Powerwall2 storing all the solar energy generated during the day. They was installed by a local installer since last September.
 
That depends on the utility. I have municipal utility and I only get wholesale generation rate. Nothing for distribution.

So, I have 2 Powerwall2 storing all the solar energy generated during the day. They was installed by a local installer since last September.
I was with Hudson Light & Power once, with a similar deal (I bought retail at $0.14/kWh, sold excess generation wholesale for $0.05/kWh, so $0.09/kWh spread on T&D charges).

Munis are (were?) exempt from net metering. They could do anything from net metering down to not paying anything for excess generation.
 
Just got this attachment from the DPU with the following note:

"During our call on June 11, I noted that the Department of Public Utilities (“Department”) was considering whether to seek comments on the issue that is causing several customers with a net metering facility that is paired with an energy storage system to experience a delay in the interconnection process. The Department decided to request written comments. Please see the attached request for comments and note question 17 on page 5. "
 

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  • dpu 17-146.pdf
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I think the DPU will issue a ruling similar to NY where as long as the power storage is exclusively charged by, say solar, and guaranteed not to draw power from the grid, the customer can keep both net metering and storage.

The utility argument is that the storage could've drawn energy from the grid. You can't have both ways.
 
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A couple of updates, the DPU did issue a ruling to allow storage + net metering. However, the Tesla Power Wall is exporting energy back to the grid for a few seconds a day which "violated" the original ruling.

What I described earlier + the storage cannot export to the grid, is the current DPU ruling.

The new case is ongoing with the DPU thus the written comment period. It is hard to say how quickly a new ruling will be made and if will be favorable to folks like you and me.
 
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A couple of updates, the DPU did issue a ruling to allow storage + net metering. However, the Tesla Power Wall is exporting energy back to the grid for a few seconds a day which "violated" the original ruling.
@yousexy: Please correct me if I'm wrong here, but, I thought based on reading Tesla's materials on the Powerwall and many posts on this forum, that it does not export to the grid. Is this something Tesla did wrong in your installation ? I'm trying to understand this issue as much as possible before making any Powerwall purchase decision. Thanks !
 
Under a rare "boundary condition" a few Watts can escape to the grid.
From Eversource's 2017 Annual Report: "New technology, energy conservation measures and distributed generation could adversely affect our operations and financial status. Advances in technology that reduce the costs of alternative methods of producing electric energy to a level that is competitive with that of current electric production methods could result in loss of market share and customers, and may require us to make significant expenditures to remain competitive. These changes in technology could also alter the channels through which electric customers buy or utilize energy, which could reduce our revenues or increase our expenses...CUSTOMERS' INCREASED USE OF ENERGY EFFICIENCY MEASURES, DISTRIBUTED GENERATION AND ENERGY STORAGE TECHNOLOGY COULD RESULT IN LOWER DEMAND. REDUCED DEMAND DUE TO ENERGY EFFICIENCY MEASURES AND THE USE OF DISTRIBUTED GENERATION, TO THE EXTENT NOT SUBSTANTIALLY OFFSET THROUGH RATEMAKING OR DECOUPLING MECHANISMS, COULD HAVE A MATERIAL ADVERSE IMPACT ON OUR FINANCIAL CONDITION..."

Isn't this what's really going on? Eversource is denying Powerwall applications because they fear loss of revenue. I don't think it has anything to do with "rare boundary conditions" where a watt or two could escape to the grid. I've been waiting since January for Powerwall approval, and I've been essentially told to get lost. Recently, Tesla tried to bully me into accepting a refund on my Powerwall deposit.

Guys: let's get real, here. Eversource is simply worried about their bottom line. If someone on this forum in Massachusetts has recently been approved for one or more Powerwalls (& has net metering), and the Powerwalls have actually been installed and up in running, let me know. Because I don't think it's ever going to happen.
 
What surprises me is that batteries do not generate energy, so why would Eversource care if I have the battery in my house. Unless I'm on time-of-use plan, and storing energy during off time and selling it back at peak times (which still wouldn't make a difference because net metering is buying energy at whole-sale prices, which is something like 2c per KWh) it really shouldn't make absolutely not different to Eversource if I have a battery in my house. Maybe I'm missing something, but I don't understand how that affects their bottom line...
 
2c per kWh, care to quote the source?

I looked up my statement last month from Eversource, it is $0.22029 per kWh for net metering.

The utilities' argument is that if the power wall can export energy back to the grid, then there is no stopping of customer who stores energy in the off-peak hour, then sell it back to grid at peak hours. TOU is coming to Mass.

The utilities will fight every inch of ground to make the process of solar panel and energy storage difficult for their customer. Let the due process plays out. But if the Tesla Power Wall does not have a bulletproof design or set up to avoid exporting energy back to the grid, I'm fearful that the DPU will side with the utilities.
 
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2c per kWh, care to quote the source?

No, that's why I said "something like". That's what I recall from my conversation with SolarCity when I was applying for net metering agreement 2 years ago. If I remember it correctly, if your solar array overproduce energy in one month, Eversource doesn't just send you money back, they will take equal amount of energy from your next month bill off (if you under-produce next month). If you consistently overproduce, and never use more then you produce, once or twice a year (as far as I recall it), you can sell that collected energy to Eversource, but they will buy it for wholesale price, and without delivery portion. Which is roughly 2c per KWh (or at least it was about 2 years ago). Now it's entirely possible that the guy that I spoke with in SolarCity misinformed me, and it doesn't work that way at all. I'm not sure, because I've only had 1 month in the last 2 years when I overproduce energy.

TOU is coming to Mass.

Great, so when it comes, block me from switching to it until I drop net metering. But blocking installation of powerwall preemptively seems like just asking for somebody to take you to court (I really wish somebody would).