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Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls

pilaenergy.com

201–210 of 492 posts

Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls

#201
post #51

1.6 KWh capacity with 2.4 KW output [0]. I couldn't find a price on the website (the $99 is just for a reservation) but from this thread it looks like it's priced at $1k [1]. For context, in the USA, 30 KWh is a rough estimate for average daily home usage [2]. [0] https://pilaenergy.com/tech-specs#faq [1] https://news.ycombinator.com/item?id=43333996 [2] https://www.eia.gov/energyexplained/use-of-energy/electricit...

Thanks for bringing more details to the thread - We've just launched, and for folks who like what they see and want to be first to get Pila the (refundable, cancel anytime) $99 deposit will lock in $999. Once we start shipping and fulfilling through other distribution channels, price will increase to $1299 Also, spot on that the average home draws about 30kWh, and with an EV driven average daily ranges that'll jump t…

This is an interesting idea and I wish you a good luck building a profitable business around it.

Before starting to apply voltage to a home electric gird, I guess you need to disconnect it from the central grid - how do you do that? Or do you detect when the grid goes down and comes back up?

Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls

#202
post #123

Earlier quoted context omitted.

Huh, I hadn’t seen ConnectDER before. That’s cute. It’s not entirely clear to me how it interacts with power sources in the house, and it’s also not clear to me whether it’s standardized enough so that a different MID could be used in its place with the same inverters/batteries/whatever. I would love to see the industry standardize on a MID protocol well enough for applications like V2H/V2G to work without absurd lev…

I've seen this "meter plug piggy back vampire tap" scheme used for EV chargers, looks cool to use it for grid tie generators too.

Tesla offers the Backup Switch which is a Meter Socket Adapter(MSA) like ConnectDER.

Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls

#203

From your site: "For homes with electricity prices that vary throughout the day, Pila optimizes charging to help manage your utility bills." Based on experiments like https://www.youtube.com/watch?v=jtNq-0kV8YM , I'm extremely skeptical. Can you back this claim? Also, why are people going to spend $1,300 on this when a good UPS is a fraction of the price, and (for example) an Anker SOLIX F3800 Plus is $3,200?

I bought lights-out manageable 400 lbs (lots of kWh) of rack mounted sealed lead acid batteries in the form of UPSes with expansions for less than $600.

The other thing is that rewiring a main panel for generator and/or solar to provide emergency power to a subset of circuits is preferred to simply trying to power everything with a tiny battery pack. This usually means adding a subpanel and an automatic transfer switch, which is a heck of a lot simpler than running extension cords through the house and much more fine-grained than powering everything with backfeed.

Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls

#204

Earlier quoted context omitted.

1. I'm actually hopeful we see a generic MID standard emerge with folks like ConnectDER well positioned to support that, so more homes can benefit and households can gain the ability to flexibly try different batteries without ripping out their panels every time. If not, we could definitely build our own (helped build 2 generations of Tesla's MID as well as 3 generations of SPAN Panels with MID functionality). Happy…

MID = Microgrid Interconnect Device ? DER = Distributed Energy Resource ? SPAN = an energy device company https://www.span.io/ ? Just had to check the definition of some acronyms and thought others might find the results helpful inline.

Correct, Thanks!

Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls

#205

As far as I know, backfeeding is illegal and not allowed by the NEC because of how dangerous it is to linepeople without a disconnect switch. A local transformer when energized by backfeed creates high voltage on lines that should be deenergized.

My guess is the battery will come with some sort of remotely controlled switch that disconnects the house from the grid, before the battery starts supplying power.

Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls

#206

From your site: "For homes with electricity prices that vary throughout the day, Pila optimizes charging to help manage your utility bills." Based on experiments like https://www.youtube.com/watch?v=jtNq-0kV8YM , I'm extremely skeptical. Can you back this claim? Also, why are people going to spend $1,300 on this when a good UPS is a fraction of the price, and (for example) an Anker SOLIX F3800 Plus is $3,200?

A UPS can usually only power 100W, not enough for most fridges. Pila can do 2.2kW, enough for fridge, microwave, internet, and coffee maker.

Absolutely true, yes. I mentioned UPSs to represent the low-end of the UPS/power station/generator spectrum, with the Anker SOLIX F3800 Plus at the higher-end (which costs only 2.6 Pikas). The video I linked to does a solid job of evaluating the pointlessness of using a more comparable $500 1.8kW Anker SOLIX C1000 for the same use case Pika is pushing, which is what prompted my skepticism.

Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls

#207
post #123

Earlier quoted context omitted.

1. I'm actually hopeful we see a generic MID standard emerge with folks like ConnectDER well positioned to support that, so more homes can benefit and households can gain the ability to flexibly try different batteries without ripping out their panels every time. If not, we could definitely build our own (helped build 2 generations of Tesla's MID as well as 3 generations of SPAN Panels with MID functionality). Happy…

Huh, I hadn’t seen ConnectDER before. That’s cute. It’s not entirely clear to me how it interacts with power sources in the house, and it’s also not clear to me whether it’s standardized enough so that a different MID could be used in its place with the same inverters/batteries/whatever. I would love to see the industry standardize on a MID protocol well enough for applications like V2H/V2G to work without absurd lev…

I agree we need a universal option for both home batteries & V2H. ConnectDER is working to be that standard. Tesla’s Backup Switch was supposed to be open, but unfortunately hasn’t been opened for others to integrate with.

Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls

#208

It looks beautiful. But I honestly don't understand what the market is. OP answered in one of the comments that it will run a single fridge for 32 hours. I understand the benefits of a UPS that will run your desktop computer during a brief power outage of a couple of hours. And I understand a generator that will keep your house running for 10 days after a natural disaster. And I understand a Powerwall that can suck u…

I agree that this doesn't seem useful for time of use arbitrage.

I think it depends on what your electric outages look like. Short outages, a desktop ups probably makes sense. But if you regularly get 12-36 hour outages, this might be a reasonable product for you. Personally, I expect two nines of utility power, so something like this could possibly work (but I already have a 35kW propane fired standby generator)

Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls

#209
Traditional UPSs don't tend to advertise capacities, so I may have an incorrect perception of what a good Wh/$ is, but isn't 1.6kWh really damn good for a $1k UPS? How'd you guys manage to pack that much capacity in at that price point?

Might be suitable for a rack assuming all the cloud bullshit can be turned off.

Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls

#210

Earlier quoted context omitted.

Yep, and to clarify Pila includes an MID onboard so while Intentionally Islanded there is no backfeed. But in terms of a whole-home disconnect, I believe we'll see more generic options appear that are somewhat DER-agnostic.

>Pila includes an MID onboard How does that work? Is just not putting energy out the input "plug" count as a MID?

The Tesla MID is in the Tesla Gateway or Backup Switch meter socket adapter. The Pila MID is onboard inside the battery. Pila can push power back through the plug.

When utility power drops, Pila & Powerwall react exactly the same. They both detect the outage, open the MID, and power load downstream of the MID. In the case of Pila it powers loads downstream / plugged into Pila.

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