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Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls
81–90 of 492 posts
Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls
#82So what is the coordination between batteries doing? Is it moving electricity through the walls to balance things when the grid is down? How is it different than a typical UPS like for servers or other electronics? Just bigger/longer lasting battery? What integration need is their with typical home systems? (Beyond things like turning them off when battery gets low?) I kind of don't really get what having an app for…
The simple case I can think of is priority charging, with total load limiting. Since solar supply is variable you want to avoid drawing from the grid if possible, and you want batteries attached to things that will draw the most expensive power (by typical usage time) to fill first.
Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls
#831.6 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 to about 60kWh.
Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls
#84Great idea. I am considering buying one for my refrigerator and furnace. Are you planning to charge a monthly fee? I’d be open to that, but it would be nice to not pay for more than the hardware. I.e. build the operating costs into the cost of the initial purchase
No monthly fees -- You buy it, you own it.
Every software-based appliance built in the last decade starts out with this promise but then inevitably rug-pulls with mandatory updates that introduce subscriptions, degraded functionality, etc.
This thing is way too "nice" and polished for its relatively low price tag, meaning it's likely being significantly subsidized by investors, who will eventually want a return on their investment and all these promises will go out the window.
Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls
#85What range of sensitivity does this offer? My US apartment complex has fluctuating levels of neutral sag 24/7/365 and it’s unclear how that would interact with your hardware.
The off-grid detection is based on a combination of voltage and frequency measurement over different time windows, so I'm sorry that I won't be able to give you an exact answer on your situation. I've lived in apartments with bad high impedance neutral connections and it did all kinds of weird things to the loads... Hopefully something your apartment complex can look into!
Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls
#86> What's been your experience with home batteries? What recent power outages have you had, and how were you affected?
I love my Powerwall, but it's not powerful enough to power my HVAC. (Heat pump in a northern climate.) I wish I spent more money on a more powerful one.
The payout I got last year for the virtual power plant was phenomenal. If they continue for a decade or so, the Powerwall will come close to paying for itself.
That being said, when I was a renter, I once went looking for a UPS for my CPAP. I never experienced long outages. (Just the one where the Tesla exec flew into a powerline and died.) I don't think I'd spend $1000 on one of these. Even if I hacked together a solar panel onto one, apartments are so small that it seems like it's overkill.
Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls
#87Two questions: 1. Have you considered building a “microgrid interconnection device” to go with this to allow the batteries to backfeed a house in the event of an outage? (This would require native 240V split-phase capability and/or an auto-transformer.) 2. Have you considered removing the fade-in-when-scrolling abomination on your website?
1: And of course some sort of isolation of the house from the grid when it's back-feeding.
Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls
#88Two questions: 1. Have you considered building a “microgrid interconnection device” to go with this to allow the batteries to backfeed a house in the event of an outage? (This would require native 240V split-phase capability and/or an auto-transformer.) 2. Have you considered removing the fade-in-when-scrolling abomination on your website?
1: And of course some sort of isolation of the house from the grid when it's back-feeding.
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.
Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls
#89off grid here for many years self built systems can do the math for solar powered,off grid sytems with battery banks, in my head. The numbers posted with battery back up system are so wildly inflated as to be absurd, laughable , 32hrs for a fridge, it wont run a big fridge for 1 hr, tiny fridge for 5 hrs. bar fridge, laptop, phone and one light might make 24hrs, might, when its new, hot weather, fergetit. the way it'…
Puget Sound Electric here in Western WA has a very nice feature showing usage by hour by day (using their smart meters). We live in a relatively small home, and do not use electric heat. Yesterday our "vampire draw" was about 0.5 kwh per hour (12am to 5am -- nothing really active). Once we got up, fired up the coffee pot, and lights, etc. we used 1.3 kwh from 6am to 7am. Pia looks like a good UPS for standard appliances, but as a whole house solution... Folks really need to understand how their home would work using a combinations of Pias. For us, we spent about $1k for a Westinghouse 9,000 kwh generator which runs on propane, and I put in the fairly inexpensive breaker and lock-out in our service panel. Costs were well below $2K. When our power goes out (which it does A LOT), simply fire up the gen, shut down all the high amp circuits in the house panel, and switch service panel input to the gen. Takes less than 5 minutes, and everything works apart from some high amp devices which we can easily live without short term. Having a good backup is important -- moreso with the power system strained and more "once a century" events.
Re: Show HN: We built a Plug-in Home Battery for the 99.7% of us without Powerwalls
#90> What's been your experience with home batteries? What recent power outages have you had, and how were you affected? I love my Powerwall, but it's not powerful enough to power my HVAC. (Heat pump in a northern climate.) I wish I spent more money on a more powerful one. The payout I got last year for the virtual power plant was phenomenal. If they continue for a decade or so, the Powerwall will come close to paying f…
Wait, a Tesla exec flew into a power line?
When was this?