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Comment by thehappypm | Hacker News Reader

Surprised at the negativity. This is great IMO! I just bought a house and am surprised by how crappy all the options for backup power generation are.

Cheapo generator: allows you to plug in some stuff but it’s very ad hoc, needs some light maintenance. Definitely good in a pinch but it’s not gonna power your house or even make it easy to keep your lights on.

Expensive generator, wired into house electrical system: great stuff but very expensive, and still requires maintenance.

Powerwall: low maintenance, terrific user experience, however exorbitantly expensive and also won’t really help in a prolonged outage.

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I have a Powerwall. It's price was competitive with a natural gas generator. I was surprised as well (I didn't expect the generator to be that expensive), but when they came within ballpark, the Powerwall was a no brainer.

It does (supposed to have) sustainability assuming it's backed by solar and you have enough sun (as with all solar caveats).

The best thing about the Powerwall is that it's not a standby system. It's active everyday. For my house, solar by day, battery by night, recycle, recharge, repeat.

This means that when the rare event comes, I don't have to worry (as much) about it not working because I didn't run the thing for 6 months. It can fail anytime, but at least I can, ideally, deal with it while the grid is up, rather than have it fail when it's actually necessary.

Also the power switchover is seamless.

The Powerwall experience is, indeed, very good.

How long do you have it and are you monitoring capacity degradation of the cells?

Not long enough to see an impact (only had it a few months, the project took almost 2 years with all of the COVID relate shenanigans).

Utilizing the Tesla apps, I honestly am not sure how I would monitor degradation over time. Perhaps were I to download the data, I might glean some insight from that. It's currently not something they highlight.

Ok! Slightly jealous with your setup, that sounds like a nice bit of kit you have there.

With a natural gas generator though, you don't run out of power once the batteries have depleted as long as you still have gas service.

> you don't run out of power once the batteries have depleted

That's definitely true if you charge only via grid, but my friends who got a powerwall bought it because they need to off-set the 9 AM to 3 PM solar into a 6 PM to 10 pm usage scenario.

Their bet is that in case of an earthquake that doesn't hit their house directly, the solar + powerwall + EVs is a more survivable setup compared to gas pipelines or a propane tank on-site.

The other plus side is that they use the device every day, so if it isn't working, they'll know in a day - the previous experience portable generators (though admittedly it is just "burning man" every year) says they need last-minute wrenching if they're idle all year.

This is exactly why I went with Powerwalls. The batteries charge during the day from our solar array and then we use the stored electricity at night.

I've only had the Powerwalls for a few months, but we've already had several four- and five-day stretches where our production was high enough and our usage low enough that we didn't buy any power from the utility at all. Contrast this with previous average power bills in the $400/mo range, which are now down to $15/mo.

There have also been a couple of brief power outages (5-10 minutes) where the only reason we knew about the outage was that the utility texted us about it before the Tesla app notification appeared on my phone.

Yeah, powerwall + solar is definitely more sustainable.

I can buy a tri-fuel 10/8kw+ generator for ~$1k, which can run all the standard stuff at home - and some extras, depending on fuel. How's a Powerwall competitive with that?

Sure, no seamless transition and a bit of light maintenance. It all depends on how many times per year you need it and for how long.

To be honest, I'd love to have a Powerwall - but with the huge cost difference it is unfortunately a no-no.

Batteries + solar means that you're producing your own electricity every day too. You can't do that with a generator unless you start cooking biodiesel in your garage.

For you light maintenance of a 10kW generator might be easy, but for most of us it isn't. It still has a ton of moving parts, each of which can fail and will be hard or impossible to replace in an emergency situation.

It's like backups, you really don't have them unless you've restored them once. With a solar+battery setup you're testing the system every hour of every day. With a generator you need to actually schedule a test time every X months and make sure the fuel is still valid.

Appreciate that what I got was a bid from a leading generator provider, and the cost included all of the installation, wiring, gas lines, trenching, permits, etc.

Also appreciate that when it comes to mechanical things in general, I seem to excel at swinging hammers on to all 10 of my left thumbs. I'm not someone who's going to "do it myself" by any stretch. Just not my gift.

I was as surprised as anyone at the overall cost of the project, and how the Powerwall had become competitive to it. I do not think I would have been as happy with the generator as I am with the Powerwall, and the daily utility of the system is just far higher than the occasional backup utility of the generator would have been.

Don't the batteries wear down after a few years? I thought the batteries were only good for a few thousand charge/discharge cycles.

a few thousand cycles * a few days of use per cycle = a decade or two.

I've got a somewhat goldilocks generator setup that involves a backfeed breaker (with mandatory interlock kit). I can run my central AC on this thing for ~5 hours per 10 gallons of fuel. The generator is "portable" and rated for 12000 continuous watts.

Its a bit of a pain to set up, but this is how I deal with multi-day hurricane scenarios living in the gulf coast region.

I debated standby generator, but the cost vs value is a difficult argument considering how often the texas grid actually experiences a multi-day event.

I am still considering something like a powerwall, but its a lot of extra crap to pay for and think about. My generator is properly winterized and will almost certainly start up if required to within the next half decade. Very simple.

How many tons is your AC? I’m also on the gulf coast and struggling to size a generator for my 5-ton compressor.

4 tons.

5 tons would definitely be pushing it on LRA/running amps for this size generator. But, this ultimately depends on the age & vendor of the compressor. Newer multi-stage or inverter compressor designs are much more likely to play well.

The opposite is often true with inverter driven compressors. It’s VFD powered which introduces harmonics and other noise from SWPS. In the data center industry you oversize your generators to deal with it.

Plus dirty power from a struggling generator will kill the VFD. I just ran into this with my ECM condenser fan motor, circuit killed by generator.

> The opposite is often true with inverter driven compressors.

This is good to know. I had simply made an assumption - The inrush current is what I was primarily concerned with.

I did not realize the other factors would cause trouble once it was ramped up to full speed. I can definitely see how dirty power from a cheap genset (like the one I have) could screw over a digital drive system.

>I can run my central AC on this thing for ~5 hours per 10 gallons of fuel.

Sincere question, since I live in the opposite climate: how necessary is running your AC during a power outage? Where I'm from heat is a requirement during a winter storm outage, but my furnace backup doesn't require a ton power. I run most of my house on an 8000 watt portable generator.

In many places in California, you'll more likely die of the heat than die from cold.

Hurricanes are followed by the intense heat and humidity of Summer in the Gulf Coast. Without AC, it's miserable.

Where I live in The South it’s 80-90 degrees for months on end with 70-90% humidity. If you’re on the gulf coast a hurricane could knock you out for a while.

I guess it's the humidity that's the killer? 90F doesn't sound too bad for a few days.

EDIT: This heat index (https://en.wikipedia.org/wiki/Heat_index) puts 90F (32c) at 90% as equivalent to 122F (50c), in which case I can see the problem!

As others have noted, it is the humidity that is the killer.

In most bad hurricanes, your home is going to leak some amount of water if you are in this region and take a direct hit. Doesn't matter how fancy your roof is. Something is going to leak.

Absent some external miracles, your HVAC system is the fastest way to dry out your house after it gets absolutely wrecked in one of these storms. The only way, even. To be clear, my setup is for the aftermath. I am not expecting to ride through a hurricane with my portable genset sitting in the back yard chugging along.

My parents have a Generac. It tests itself every Tuesday at noon. It always seemed fine. But the first time they needed it, something failed. I'm not sure what, but I think it was in the electronics and software. Even the best tests can't catch everything.

Probably a no load test. I put mine online and do a transfer test weekly.

This is great, but don't discount the fact that you can have some battery backup for under $5k USD (~15kwh). Granted, you won't have ~100 kWh of storage, but in most places (in the US), the grid isn't so unstable that you'll regularly use it.

And of course it won't power your home at normal consumption days (or even 1 day), but it works for emergencies.

I am curious to hear of hands on experience with http://www.generlink.com/ .

It is a medium power transfer switch that installs behind the electric meter, meaning that the existing panel can be used to select loads.

With a lower quality generator, you probably get ~3kW for less than $5000.

I really dislike the complexity of the automatic transfer solutions and I especially dislike the concept of preferred breakers or sub panels for generator use, etc.

Instead, just buy the $30 metal lockout tab for your panel and wire your generator right into the main panel and be done with it.

So. Much. Simpler.

Power goes out, you flip the lockout over and manually start the generator. Worried about loads ? Fine - while the panel is open, flip off your dryer 30a and … ?

In reality, load is not an issue - a generator with 100amp breaker will power your entire house.

(I even tried to break it - ran dryer, 20amp microwave, toaster and kicked on a water pump … no issue)

Can you explain why automatic transfer solutions must be more complicated? Is it because they must constantly monitor the power situation to know when to kick in?

I've installed this, the price approaches/exceeds the cost of entry level automatic transfer systems but with the functionality of a manual system. I think most would get more value out of something cheaper or more expensive. Also, because it sits above your breaker, you're introducing a new point of failure to your home's electrical supply. If a transfer switch fails, you don't have generator power. If this fails, you have no power whatsoever until it can be removed or replaced.

Cheaper: Interlock switch. Most local codes allow a UL recognized interlock system to be used on the panel that physically prevents the main panel breaker from closing while the generator breaker is open, and vice versa. You have to install a special outlet to the generator breaker, but as long as it's close to the panel, this does not cost a lot. Functionally this is the same as the product you linked, but for ~$150 plus installation vs ~$850 plus installation.

More expensive: automated transfer panel. If you need to use the generator frequently, this is what you want. Even if you use it infrequently, automatic transfer is so much more pleasant than having to go to the panel, flip the right breakers, turn on the generator, then do it all over again when the power comes back on. You can get a basic one for about the same price as the generlink device you linked. 200-amp whole house switches can be installed for $2000 or less

If it was me, I would not even bother with a manual system. For infrequent use, you can get a window insert that lets you feed extension cables through a window without letting in bugs or cold air. If you're using it more than once or twice a year, $1000-2000 for an automatic transfer switch is not that bad compared to the cost of a generator and will make the experience of using it much better.

The only situation I can think of where a device such as this would have an advantage would be one where you cannot permanently modify anything. It is in fact very quick and easy to install, and can be removed without leaving any permanent changes.

My main use case is powering the blower and pumps on my furnace, so cords won't really work.

When you say you've installed it, you mean for someone else?

I kind of had the sense that it was expensive relative to the utility it provides, but it is nice and tidy.

during the freeze in texas last year I cut the hardwired cable to my furnace and added a plug. I plugged that into an extension cord to a 2kw honda generator and it worked great. I had an electrician clean it all up after the freeze so my furnace now has a permanent plug into an outlet.

I did add an interlock and a 13kw generator that will mostly power the house.

7.5KW Generac $2000 plus installation

https://www.northerntool.com/shop/tools/product_200665207_20...

Realistically, you have to look at it from a "convenience/dollar", since power outages are generally rare.

With the general infrequency of power outages in most places, getting portable quiet generators like Honda EU ones and running an extension cord inside your house is pretty much the most cost effective solution. You can chain 2 EU3000is together for 6000 watts, and only spend $6k, and run them out of your back yard without disturbing the neighbors.

The other issue that you have to consider with Lightning is that while its good for occasional outages, for every watt you use, you slowly lose the ability to drive away if shit goes south, with no easy way of effectively getting that charge back. If anything, the current Hybrid F150 is the better choice for powering your house.

Just remember then when all of your neighbors have power out as well that those small generators often “grow legs and disappear” … it is a very good idea to chain them up.

Also _always_ ensure the exhaust is no where near any open doors or windows. Small portable generators are exceptionally dangerous for carbon monoxide poisoning.

All that said these small generators are fantastic and they can even easily be setup to run from an external fuel tank to increase flexibility.

I run mine out of my garage with the garage door cracked and a fan pointed to push the exhaust out the crack. Have monoxide detectors in the house for safety.

generators and power walls make sense only for hospitals and stupid-rich people (edit: and remote setups)

You probably have a couple things you need to keep running during a power outage. A decent consumer nobreak will be more economical and efficient.

This is marketing. This car is being marketed to the same doomsday people who buy guns because the coming collapse of civilization. Pure fear based marketing.

It's not all doomsday prepper marketing. Adding Vehicle to Load (V2L) or Vehicle to Grid (V2G) is not a huge increase in BoM.

The F-150 already has multiple AC outlets in it, in a pinch you could just carry your fridge next to it and plug it in :)

This is just Ford doing a proprietary charger that can automate switching from grid to V2G mode if the grid goes down.

I have a generator that can power everything in my house except my air conditioning. It plugs into the side of my house. The total cost in todays dollars is less than $1k usd.

I’ve used this generator to power me through outages that have lasted days.

It’s been relatively low maintenance and the maintenance that exists is taught in YouTube videos.

Reading elsewhere in the discussion, using the truck in this manner requires equipment that starts to get closer to the price of a Generac.

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