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

pilaenergy.com

251–260 of 492 posts

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

#251

I definitely like it. I experience regular outages and have a whole home generator because of it. But that takes time and isn't cleat. So this is basically how I already have everything set up, with ~6 UPSs scattered around. And I have looked at the whole home systems to get away from that. But the mesh with smart features is definitely interesting. Does it have any power cleaning functionality? I have occasional iss…

It does have power cleaning functionality when it's off-grid, let me check in with hardware if it does that in pass-through mode. Voltage drops it should detect and cover though. Automatic load shedding will be configured by appliance priority we were thinking, but open to feedback. The fridge should go out last, the wifi first. We're using a 1.6kWh LiFePo! Replacement is something we're working hard on, I unfortunat…

Probably only passing power through when it's still on-grid, because it's more efficient is our current plan for now. Surge protection we will cover though, just voltage drops are not planned to be covered for above reasons.

As soon as the power's going through our inverter, it'll be the clean sine wave you are talking about.

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

#252
post #201

Earlier quoted context omitted.

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?

Pila detects when the grid goes down & when it returns. This is done by all home batteries & Pila is no different.

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

#253

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…

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…

The portability of the unit also makes a great use case for off-grid, getaway or usage in a remote location, or perhaps just as an additional option for existing setups.

Being able to plug it into a NA standard plug into a more capable generator (or other outlet) to recharge is useful.

Without knowing the price point... van life folks have solar batteries and the published power specs seem to be competitive and useful for powering higher-draw appliances and devices.

The payback period to make arbitrage useful would be very specific to the user and how much electricity costs in their locale, but this calculation should take into account the delivery costs component of a utility bill that can be the same or higher than the cost of the actual electricity.

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

#254

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…

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…

Have you looked at any of the integrated options?

Apparently a company in San Francisco put together 110V electric stoves with induction cooktops and integrated batteries --- they then sold them to folks applying for tax rebates to replace gas stoves in kitchens which weren't wired for 220V.

One notable appliance you don't mention on your website is electric water pumps for wells in rural areas....

Similarly, are your devices able to provide sine wave power to run small electric tool motors? Folks with CNC machines might be interested, or perhaps they could run tools on jobsites? How many small tool batteries could be charged from one? Would it fit in a Systainer? Might make a nice fit for folks w/ Festools.

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

#255

Earlier quoted context omitted.

> 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...

That’s much too conservative in opinion, at least around eggs, cheese and dairy.

In the US our store bought eggs are washed and are not safe to store unrefrigerated. If you get your eggs from the back of a hen it's a different story.

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

#256

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.

Is there any reason this won't eventually be commoditized?

The retail cost (low end) for lifepo4 batteries is $125/kWh, and for hybrid inverters it's $175/KW, thanks to decades of Wright's Law.

Currently Pila is $625/kWh, but what is stopping it (or clones) from being $200-400/kWh eventually? Their high prices are probably temporary artefacts of (1) lack of current scale, (2) premium due to UI/brand/lack of competition. But markets will catch up.

If the price does drop to that level then it's a big deal because you don't have to pay labor installation costs, which is a large proportion of total costs for end consumers.

The main question I'd have at that point is about electrical and fire safety relative to the standard setup.

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

#257

I have two questions: How are you funded? Hardware products are capital intensive. The cost of inventory alone can be a killer. The problem with buying a product like this is that an underfunded company can go "poof" inside of a year by quickly getting over its skis and gasping for air (money). And, of course, warranties are only as good as the life of the company. How much/how was it tested? Managing power can be da…

The real business model here is to sell these at a loss and build up an install base to aggregate them into a "virtual power plant" that can provide large-scale distributed power source/sink capability and sell access to that to utilities. That's why it's got cellular connectivity for which they are preemptively footing the bill (you wouldn't do that without good reason).

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

#258
post #67

What a noble mission to make energy independence more accessible like this, even to renters! I read your site, watched the video, but I still don't understand why you implemented a mesh network? Why multiple batteries need it to synchronize? Aren't they completely independent? Why would the fridge battery need to communicate with the other battery powering your lights? Also, as an angel investor, I'm curious to know…

To give more functionality around energy management, we wanted all of the batteries to be able to work in concert. We could have gone with "any old wireless" network to coordinate the batteries. One thing that's really stuck with me from building products at Span and Tesla is how important reliable connection is over years of operation. Depending on consumer wifi is a huge pain for reliability (changed passwords, inh…

Did you consider using homeplug, IEEE 1901, or some other network over powerline standard? I imagine it being more reliable if they're all behind the same breaker.

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

#259

Judging by the negativity here you're going to be a massive success -- search up the dropbox, airbnb, coinbase and ethereum launch threads if you want to feel good about where you're at. :) That said, I like this idea -- a modern coordinated UPS. I live in an area where people have 3-10 days a year of no power; being able to pick and choose what power they'd use during an outage would be a significant benefit to them…

I personally remember sh*tting on doordash...what a stupid idea.

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

#260

Earlier quoted context omitted.

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…

You buy lithium battery (lifepo4) not agm, much longer life time. I have exactly the same Vevor inverter + lithium battery total cost was 400$. But I regret doing this setup, I should have just gotten Ecoflow power station, it's a bit more expensive but more versatile.. You can take it with you anywhere

Thanks for the suggestion. It looks like 100Ah LiFePo4 batteries are pretty easy to find too.
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