Home generator specs?

[::: :::]

Any sparkies out there have any general recs or things to consider when looking to add a generator to your home? Cost expectations w/in +/-$5k? Diesel vs propane? Length of outage to plan for (2wks?)?

I work from home. We have a separate studio building on the property. We are in a residential zone that seems to be a last priority when power goes out. Power is all above ground and not likely to get buried city wide any time soon. We are in a forest. It’s out today. Again.

Interested in whole property regaining power, but will also consider just essentials.

200A panel to the property
3000sf conditioned space incl studio
Heat & domestic water on gas fired boiler (elec controls/pumps)
3 mini splits cover A/C (were retrofit to the house recently & we never use for heat, just cooling...prolly not essential given our climate)

Work requires very little: running lights, a server & 3 computer stations

[Foggy_Goggles]

My parents have a Generac with a buried propane tank and all the smart controls. It's a pretty awesome system that self tests and self starts. My dad said they lost power once and it was up and running in 30seconds. They contracted with a authorized dealer who handled the whole scope of work.

[hawkgt]

My parents have a Generac with a buried propane tank and all the smart controls. It's a pretty awesome system that self tests and self starts. My dad said they lost power once and it was up and running in 30seconds. They contracted with a authorized dealer who handled the whole scope of work.

/thread

[jackstraw]

/thread

Naw.

Kohler generators provide cleaner power.

Also, everyone oversizes their generator as if they're going to live off the grid for months. Maybe you will, but what's the reality of your situation? We might lose power for a half a day to a day and that's even rare. Save money and size down to run essentials because the grid will be back soon.

[::: :::]

Worst we’ve had here is 7 days without power in a snow event (very rare but hey it happened)
Typically it’s been less than 48hrs but often during the work week

[ötzi]

We had a bigass 40kw CAT propane system for the past 15 years in the house we just sold and have a Generac natural gas system in the new place. Maintenance is drastically less money with the Generac system and having it hooked up to the gas line removes one variable (it adds another, but if the gas lines go dry we've got major problems anyways). Personally I like this setup better.

A 22kw Generac system is about $5K. Sitework, gasfitting and electric is all variable depending on locale and existing conditions but another $5K should probably cover it, maybe with a bit to spare if it's a straightforward install, or a bit more if it's complicated.

The system is quiet, runs once a week for 10 minutes to self-test and has been trouble-free so far (5 years). It's got a status light that I can see from the back door, it's reassuring to see that green light as you go out. When the battery needed help this spring the light changed to amber and I knew it needed to be looked at before it became an issue, I'm told it would have gone red eventually if the system had become non-operational.

We've got everything hooked up to it except the AC. Maintenance is annual and very cheap compared to the CAT system at about $250/yr. At this point I would recommend Generac for sure.

[Timberridge]

Depends if you need sparkle motion.

There's probably differing opinions on this but we just had one installed last week. The contractor reps all the major brands (Generac, Kohler, Cummins, etc). He recommended Kohler over Generac. Unless you need every appliance and light on at the same time you get a load management system with the generator. It's a big box that goes next to the service entrance. Ours is a NG fueled ~15kw and cost $11K to install--you can monitor the vitals via a cell phone app. You want a guy who specializes in generators to do the install.

[BCMtnHound]

Local SAR installed a 20kw cummins on propane last year. Like the generacs mentioned, self tests and annual maintenance is a breeze. Costs in line with what Ötzi said ~$10k

For our home, we have a 3000W and 2000W honda portables on gas. Plenty of power to run a couple of cords to the fridge and freezers, and to a couple of space oil heaters in the basement to keep the water lines from freezing if the hydro goes out in the deep winter. They were both purchased 2nd hand for about a 1/3rd less than new. None of this keeps the internet on - would have to go satellite to retain that luxury in a valley-wide outage.

[Beaver]

If you can, hook up to Nat gas. Generac engines are actually designed to run generators, they're not a vehicle/machinery engine with a generator bolted to it as are almost all the others.

[Dhelihiker]

Naw.

Kohler generators provide cleaner power.

Also, everyone oversizes their generator as if they're going to live off the grid for months. Maybe you will, but what's the reality of your situation? We might lose power for a half a day to a day and that's even rare. Save money and size down to run essentials because the grid will be back soon.

Im in construction and we put a bunch of Kohlers in with propane tanks for a water district in remote areas. They are sweet.

[Timberridge]

If you can, hook up to Nat gas. Generac engines are actually designed to run generators, they're not a vehicle/machinery engine with a generator bolted to it as are almost all the others.

Not sure where you are getting that info. They are all glorified lawnmower engines designed to run on propane or natural gas. Once you step up into 20KW+ you are usually getting a bigger diesel engine, but then noise and cost go up significantly.

[jackstraw]

Not sure where you are getting that info. They are all glorified lawnmower engines designed to run on propane or natural gas. Once you step up into 20KW+ you are usually getting a bigger diesel engine, but then noise and cost go up significantly.

Yeah, just a motor. The alternator and voltage regulator is where the brains are at.

And good luck finding a generator right now. Put those on the COVID list as well.

[Jethro]

We are looking to install a generator on an existing house with a 600 amp service. Our local utility looked at the house’s billing history and said a 70 amp output generator would cover their usage. We are looking to put in a 100 amp unit. This would power the whole house, which seems strange to me. Usually we have a dedicated panel backed up by the generator for specific crucial loads

It will be a natural gas unit. There will be no issues with fuel going stale. We wired up a generator at an investment firm years ago and every six months they drain the diesel out and refresh it with new fuel

[::: :::]

And good luck finding a generator right now. Put those on the COVID list as well.

I wondered about that

[jackstraw]

We are looking to install a generator on an existing house with a 600 amp service. Our local utility looked at the house’s billing history and said a 70 amp output generator would cover their usage. We are looking to put in a 100 amp unit. This would power the whole house, which seems strange to me. Usually we have a dedicated panel backed up by the generator for specific crucial loads

JFC...600 amp service? Those people cannot be inconvenienced with a power outage. They need to run the dryer, toaster, and christmas lights when the power goes out.

[ötzi]

jackstraw, I'm curious about the "cleaner power" with Kohler, what's that about?

[Jethro]

JFC...600 amp service? Those people cannot be inconvenienced with a power outage. They need to run the dryer, toaster, and christmas lights when the power goes out.

400-600 is kind of run of the mill here. 8-1200
Are the big services. It would be interesting to see what percentage of that they actually use

I wired one house and it had 570 amps dedicated for the roof heat tape system, split into 30 thirty amp 240 circuits. Just for eave and gutter melt. Another house had 12 gas boilers, of which 9 were for deck and drive snowmelt

[Jethro]

I have an Onan Cummins rv generator which was given to me. It has two 120v 30 Amp circuits, but they are on the same phase. I can’t power my well with it, so I’m looking for a replacement generator. It’s a shame, since it is a really high quality generator.

[mattig]

You want to come borrow the Honda? I've used it many times to run router, modem, computer, and refrigeration.

Can't believe we live 20 minutes away and have never had an outage last more than 6-7 hours.

[exsparky]

I have an Onan Cummins rv generator which was given to me. It has two 120v 30 Amp circuits, but they are on the same phase. I can’t power my well with it, so I’m looking for a replacement generator. It’s a shame, since it is a really high quality generator.

It is a nice unit.
The older generac's sucked but about 20 years ago they got their crap together.

I've done a lot of generator work.

[k2skier112]

Not sure where you are getting that info. They are all glorified lawnmower engines designed to run on propane or natural gas. Once you step up into 20KW+ you are usually getting a bigger diesel engine, but then noise and cost go up significantly.

That makes as much sense as all cars and their engines are the same...

Briggs and Generac had a joint effort to design and build the first Briggs Vanguard engine one that would compete with Honda engines

So, yes all internal combustion engine are very similar, but these types of engines (original Generac engines and Briggs Vanguard) have many more parts built for durability and constant loads

::: :::, a Standby unit of 10-15kw would be a good choice. If you have NG, go that route

[Timberridge]

ffs, are we now arguing who builds better lawnmower engines? You people will argue about anything,

[ctsmith]

Not for the OP, but if average outage time is less, and loads aren’t crazy high Tesla’s are a good alternate if your utility has a program where you “lease” them for minimal cost vs. buying them on your own.

[schuss]

Every person I talk to in the biz hates Generac and says to get a Kohler. We have a 14kw Kohler that's outage->power in 8 seconds. It's awesome.
Generally the best rule is to size near-full load. Only limitations will be something like "can't run washer and dryer simultaneously" which is fine.

[frorider]

Yeah I think I’ll eventually go the powerwall route. Meanwhile my $300 portable gen is enough. Our internetz etc is backed up with a simple battery system for those occasional <6 hr power outages.

Those Asspen homes are singlehandedly killing polar bears. Respect.