Be thankful you have these options. I'm on a municipal electric company - no option for TOU, no funds from the Renewable Energy Trust Fund, and no net metering. And 17 cents/kWh (customer savings, indeed
)
National Grid - Time of Use
Wow, Nat Grid does have a 2,500kwh per month average one must meet, in order to qualify for peak/off-peak electricity pricing. I am not sure how they pulled off what amounts to the effective disqualification of 90% of their customers (avg U.S. consumption is ~750kwh/mnth). We're ~3,000 sq ft. with a/c, electric water heat, etc, and only get to ~2,000kwh maybe 2-3 times per year, with a Volt.
It looks like the Nat Grid discount wasn't big, anyway (7.99-1.928= 6 cents/kwh). The base rate would fall between $.13/kwh and $.20/kwh, considering supplier, etc., charges of 8-9 cents. NSTAR has no such requirement and spreads about the same for Oct-May, but gets a lot back when they upwardly
adjust the peak rate to $.30/kwh from 9-6PM during June-Sept.
-This is the sting daytime A/C can give you. I've been on NSTAR TOU, and typically keep off-peak to peak watts in a ratio of around 4:1. So, its still worth it.
Municipal utility pricing can vary. I do analysis, from time to time, on the MA utilities and found the off-peak rates of the public entity "Massachusetts Wholesale" can be extreme. About 29 municipalities actually own a percentage of nukes, like SeaBrook, and in towns like Reading offer
rates as low as $.03/kwh overnight, all-in. Try your Zip code on whatsmypower.com, as an initial portal through which to determine how you'd fare.
If you are with NSTAR, be prepared to be persistent, as you sign on to TOU. With a Tesla, I think you'd be hard pressed not to come out ahead. The state also offers a $750 rebate on hybrid water heaters, which I kid you not, can cut ordinary kwh consumption by more than 50% (they can also be put on a timer).
As far as solar, MA looks like a battle of solar companies on utilities, rather than one where the customer is significantly at the table. I'm not certain, but municipal utilities and the big boys can reject net metering, once they've reached a pre-set cap (~4% of peak load). The point is you will get nowhere, if you live in an area with a utility who has already signed up so many households. For NSTAR and Nat Grid, this applies to their entire state footprint. The smaller, public utilities may have other tools to neglect you, but
a lot of this is changing as many states, including MA, reach for unlimited solar caps. So, you might yet get signed up, but beware that other cash flows in the analysis of "whether to go solar, in MA" may also be at play.
Solar advocates and utilities discuss net metering future for Massachusetts | PV-Tech
Utilty pricing is very tricky. In states, like MA, where deregulation took effect, the for-profit distributors can't own generation (supply), but do end up being the ones to pass on the off-peak savings ordinarily associated with cheap power, overnight.
