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

pilaenergy.com

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

#181

Post by suresk »

pedalpete wrote: post #58

I love the design, but I wonder about the "selling feature". How many people regularly experience power outages (ok, if you're American relying on Canadian electricity, you might have a right to be concerned). I'm surprised you're not touting the "save on your power bill" benefits. Could this not store power when rates are low, and use the battery when rates are higher, while maintaining a balanced minimum storage am…

> I'm surprised you're not touting the "save on your power bill" benefits.

At ~$600/kWh for capacity, the ROI isn't great. I have a pretty big differential on my rates because I have an EV, and even then I'd need over a decade to make the $1,000 back assuming I fully discharged it every day.

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

#182

Post by coleashman »

the__alchemist wrote: post #122
abetusk wrote: 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...

Given these stats and the price in the sister comment, this costs $24,400 for a day of backup. This makes the LCD displays on the front page of the website listing "5 days 6 h ours" and similar on a single unit very misleading. That amount of backup would cost $128,000.

For folks that are looking for true whole-home backup, with every load protected, investing in something like a Powerwall would be the way to go. I don't see Pila trying to compete with whole-home systems. We were inspired to build Pila because many folks I've spoken with over the years are most concerned just about backing up a few key loads (fridge, wifi, charging phones, some lights). For them a $10-30k whole home system is a lot of extra spend, and if they rent those systems may be off the table to begin with.

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

#183

Post by gwbas1c »

jasonjayr wrote: post #150
xtracto wrote: post #120

Earlier quoted context omitted.

At first I thought it was some kind of UPS that would automatically "inject" AC to the house when it detected that there was no current in the mains (hence the connection to mains). But it seems it is just a glorified UPS... is that what the tesla "Wall" is?

A "no Electrician required" device that plugs into your wall and back-feeds power is a HUGE safety issue, and a HUGE no-no. Half the problem with home-generation is a cutoff/sync device that synchronizes the frequency of your local generation with the grid, and kills power going back into the grid from your home generator when there is an outage, so line workers can do their jobs safely. And unless there is a more ex…

There is some merit to using it with appliances like refrigerators and washing machines. No backfeeding needed.

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

#184

Post by coleashman »

pseudosavant wrote: post #174

I’d love for something like this to be great, but the economics just don’t make any sense. This is a 1.6kwh battery for $999. You’ll never save what it cost to buy the unit before the battery is worn out. It’d be hard to save more than $1-$2 per day.

Energy arbitrage value depends a lot on your utility, agreed. For most home battery systems it's a 5-7 year payback, even with solar. In my experience most folks investing in these systems are also putting a lot of value on the backup power, and from the data/insights. The average fridge in the US has $300-500 of groceries inside, and some insurance providers offer as much as $600 per outage to pay for spoiled food. So for folks contending with frequent outages, we're excited to offer more peace of mind value while delivering some additional smart energy management value on top

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

#185

Post by VectorLock »

josefresco wrote: post #7

So this is a per-room/per appliance battery system? Not sure how this would work for my oil burning boiler, which requires power but has no "plug". Maybe this is better for households that run 100% electric for HVAC?

Get an electrician to put your oil burning boiler on a plug, then you can plug it into whatever source (UPS, generator, UPS with fancy marketing) you want.

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

#186

Post by dharmab »

crazygringo wrote: post #144

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…

> it'll stay cold enough on its own for a day without power as long as you don't open it much.

Food in an unpowered fridge will be unsafe within 4 hours: https://www.foodsafety.gov/food-safety-charts/food-safety-du...

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

#187

Post by jodoherty »

quesera wrote: post #153
jodoherty wrote: post #148

Earlier quoted context omitted.

I might get this for my basement sump pump in case the power goes out during a storm.

A suitable UPS for that application costs less than $100.

Do you have any examples? I haven't seen what you're describing despite shopping UPSes, but something less than $100 that could last 10+ hours would be amazing.

My $200 1500VA/1000W CyperPower UPS could handle a short one or two hour storm, but storms can last for 10+ hours here during the wet season. One long power outage could cost me a lot more than $1000 in basement damages (my basement is finished).

A comparable all-in-one product to this pila battery would also be around $1000: https://us.ecoflow.com/products/delta-2-max-portable-power-s...

You can easily cut that in half shopping for an inverter and battery separately:

$240 for an inverter: https://www.homedepot.com/p/VEVOR-2500-Watt-3-4-HP-Sump-Pump...

$200 for a battery: https://www.homedepot.com/p/Basement-Watchdog-Maintenance-Fr...

But a lead acid battery might last 5 years where the pila battery is designed for 10+ years, so you're looking at $400 total on batteries. That quickly gets close to the $1000 for one pila battery.

I want to believe $100 is all you need, but to me the math with the numbers that I've seen suggests $1000 is not unreasonable for something like this.

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

#189

Post by __d »

coleashman wrote: post #100
__d wrote: post #60

Earlier quoted context omitted.

I’m in Australia and everything is 240V (well, I think technically it’s 230V now) here. Any timeline yet for international distribution?

On a personal note, I'll also be really stoked when we're shipping to Australia. Lots of friends down there, and have been lucky to work on some past home energy products for the Australian market. Parts of Pila's power electronics are already 230~240V capable. We've just launched in the US, and are doing our best to stay focused on excellent support for our home market before expanding. That said, I could see 2026 b…

Best of luck -- hope to see it available here soon!

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

#190

Post by nikodunk »

Aurornis wrote: post #167
nikodunk wrote: post #156

Earlier quoted context omitted.

Great points! This is meant as whole room backup - so it’ll keep your fridge (and a few other small devices like wifi, etc) running for 2-3 days - a pretty long outage. It’s basically a huge, 21st century UPS. It can also do arbitrage and charge when it’s cheap and deploy the power when it’s expensive. The main problem with a powerwall is it doesn’t work for renters, and costs 20,000+ (and permits, etc) if you do own…

> Great points - however this can keep your fridge running for 2-3 days (a pretty long outage). Your own marketing page claims 32 hours (a little over 1 day). It's the very first icon in the table. EDIT: And your other comment now says 3-4 days for a fridge ( https://news.ycombinator.com/item?id=43338397 ). Getting hard to believe all of these different numbers.

TLDR depends on the efficiency of the fridge. You’re right of course though - I edited linked comment to be more conservative at 2-3 days also. I can get my personal lab fridge to last 5 days though (110W power draw, once every hour for 5 minutes). :P

If your outage is longer than expected, the battery will recharge in a little over an hour and be ready to go again (if the grid comes on for a bit, or from your generator, a neighbor's etc).

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