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Vermont replacing power plants with home batteries

389 points · 304 comments · devonnull

  1. bentt · · focus · HN ↗
    I live in Vermont. This is the first I've heard of this. But I like it!
    1. raddan · · focus · HN ↗
      I live just over the border in Massachusetts and we have something similar, called ConnectedSolutions. It is essentially the same kind of program except that the benefit is a 0% loan on the battery purchase. I have a 15kW battery that allows me to power the entire house overnight without drawing from the grid. When the power company wants to draw from my battery, they send me a notification through my battery’s app. I can opt out some fixed number of times, too. And, just as when my solar runs net negative, the power company pays me (in bill credits) whenever the virtual power plant draws power.
      1. ragnot · · focus · HN ↗
        Just found out about this. Any big draw backs to enrolling in it?
        1. raddan · · focus · HN ↗
          The only drawback, really, is that sometimes you _want_ the charge in the battery for yourself. If you take out a loan with a ConnectedSolutions clause (e.g., a MassSave loan), you are obligated to make your home battery available as a VPP under the terms of the loan.

          Fortunately, one of the valid reasons for opting out from a "VPP event" (which is what my battery mfgr's app calls it) is a coming storm. In fact, in my system a "storm hedge" (where the battery tops itself up before a storm) trumps a VPP event, so for all practical purposes, there is little inconvenience. So there aren't really any drawbacks. And when you are done paying your loan you can either stay enrolled in ConnectedSolutions or not.

          I say go for it. A 0% loan is great, and it was the deciding factor for us to buy the battery. Honestly, I wish I had bought a bigger battery! 15kWh is good for an evening, but not quite enough if the following day is rainy.

          1. ragnot · · focus · HN ↗
            Nice! Any recommendation on brand?
            1. raddan · · focus · HN ↗
              I bought a FranklinWH, both for technical reasons and because I could not in good conscience purchase a Tesla battery. I like the FranklinWH. However, I discovered that it is extremely chatty with a large number of hosts located in China. Most of the hosts it chats with are hardcoded IP addresses. This worries me a bit, not for xenophobic reasons, but because it strikes me as brittle. That said, I did end up putting the device on its own (firewalled-off) subnet. Although the app is kind of opaque, it works fine, and I mostly get the information I want via HomeAssistant, which has a FranklinWH plugin. I'm not sure if I would buy it again but it gets the job done.

              My other equipment is mostly SolarEdge, which is excellent and well-behaved. SolarEdge now has batteries too-- I would probably look into them were I to buy a battery again.

              A couple things to note. If you get a battery do not put it near your house. Generally, energy storage has a good safety record, but if they do experience thermal runaway, the fire effectively cannot be extinguished until all the fuel is consumed. Mine is 75' from my house because I have a solar groundmount array. Second, my solar installer initially set everything up using wifi, including a high-gain antenna because the array was so far from my house. I pointed out that I had an ethernet switch in my basement, so they ran hardwired networking through the power conduit to my house. Much more stable. Just ask for ethernet upfront if you can.

              1. ragnot · · focus · HN ↗
                Thank you so much! This is really helpful.
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