Looking for Advice - Backup Generator

[Mike]

Our place in Wisconsin is on a rural tract. Our power delivery has been pretty reliable, but an extended outage could pose a serious problem, particularly in the winter. 

 

We've decided to install an automatic backup generator, and would be using LP as the fuel source. I sort of/kind of/not really understand the basics, but would like some advice regarding brands, technology, sizing, etc.  Our home has roughly 3,500 square feet of finished space, and is highly energy efficient. 

 

Where do do I start? Where should I end up?

 

[Sonor]

We contacted a couple of sources before we purchased and had the company install ours.  You will find that the technology approaches from different companies makes it a bit challenging but you decide for you which is best.  Case in point, Generac said we needed a 22000 kv for our whole house while the Briggs and Stratton company said they can put devices on our appliances that will regulate when they turn on. (based on the startup of an appliance draws much more power than when it is running)  So the Briggs guy said we only needed a 20000 kv.  The Briggs came with a 10 year warranty and the Gen only 6 (as did a quote from Cummins - 6 yr)

We went with the Briggs for a couple of reasons but the main one was it was not a big box store installing it. We have been happy with it.  However (yup, here it comes) apparently (according to the Briggs company) if you have LED lights on a dimmer switch, they will flash under draw from other appliances.  Also, our dryer does not pull a constant load so you will hear it groan on occasion when it pulls more power and the generator is attempting to supply the new need.  Both of these are due to the generator supplies the power needed at the time so it takes it a bit to get up to speed to generate the power.  It does not supply a constant amount of power figuring that is the max needed.

The other things to think about is the noise, the exhaust, and county codes.  Most run with the sound of a lawn tractor or a little louder.  They also have to run about 20 mins a week to ensure the engine is oiled and working.  So loud outside your bedroom or living room is not always acceptable.  The exhaust on some models point outward which will bake your lawn for about 3 feet in front of the exhaust.  County codes will also dictate (to some degree) placement of the generator.

One last thing - water cooled vs. air cooled and run time.  Ours is air cooled and has no expected run time.  In other words, our neighbor just got a Generac installed and said his has to turn off every 16 hrs. to cool down, not the Briggs.  Not sure if a water cooled will also have that same requirement ...

 

I hope this helps.

[Rougarou]

This:

 

With enough of these:

 

Or just get a measurement of the items you absolutely have to have, get an electrician that specializes in these things to do a load test and then find out the minimum size you would need.

 

For our three bedroom four bath house at 3000+sqft, I only need 14kv.  This is a house that is all electric save for the stove and two lp fireplaces (250gal tank).  We do have solar, but in a power out, solar shuts down as to not backfeed the grid and nuke a worker.

 

Your biggest issues are start up.  And chances are, every high voltage item won't start up at the exact same time.

[Mike]

Good info so far. I've considered the possibility of solar with storage, but my initial guesstimate is that it's probably 4-5X the initial cost of a generator (we looked at it when we were building, six years ago). It's appealing to me, but I'm not sure I want to take on that sort of cost/debt at this point. I'd also note that winter months can be fairly gloomy, so I'd have to investigate how many panels would be necessary to stay on top of our needs. It would be nice to go off-grid, if feasible, but our monthly electrical costs are $130-175/month, so the break-even point would appear to be way down the road.

Tell me more about why you opted for Tesla's storage unit. I've heard that, relative to other storage solutions, it's quite a bit more pricey.

[szurszewski]

I just read an article yesterday that tallest about actual market share vs brand awareness. The main gist was that most people, in the US, want a Tesla powerwall when they are installing systems (based on customer requests as reported by installers) but only a small percentage of people get them. This disparity was attributed in small part to installers having more experience with/directing customers to other systems, but mostly because there is only a very small volume of Powerwall batteries for sale. 

[Rider1200RT]

1 hour ago, Living the Dream said:

This:

 

With enough of these:

 

Or just get a measurement of the items you absolutely have to have, get an electrician that specializes in these things to do a load test and then find out the minimum size you would need.

 

For our three bedroom four bath house at 3000+sqft, I only need 14kv.  This is a house that is all electric save for the stove and two lp fireplaces (250gal tank).  We do have solar, but in a power out, solar shuts down as to not backfeed the grid and nuke a worker.

 

Your biggest issues are start up.  And chances are, every high voltage item won't start up at the exact same time.

 

I am surprised that your system doesn't switch off the main circuit to your house from the street in order to avoid killing a worker.

 

[Rider1200RT]

I'd get a water-cooled generator either running on natural gas or propane if you can. Having needed a back up generator many times after hurricanes I can say the bigger, the better.

For us AC is as important in the summer as heat is up north in the winter. AC pulls a lot of amps when starting up so you need to look at the AC unit(s) for startup amp draw, add lights, fridge(s) garage doors etc.

Depending on your total amp draw go with the bigger of the units offered by your installer. YMMV

[Rougarou]

1 hour ago, Mike said:

Good info so far. I've considered the possibility of solar with storage, but my initial guesstimate is that it's probably 4-5X the initial cost of a generator (we looked at it when we were building, six years ago). It's appealing to me, but I'm not sure I want to take on that sort of cost/debt at this point. I'd also note that winter months can be fairly gloomy, so I'd have to investigate how many panels would be necessary to stay on top of our needs. It would be nice to go off-grid, if feasible, but our monthly electrical costs are $130-175/month, so the break-even point would appear to be way down the road.

Tell me more about why you opted for Tesla's storage unit. I've heard that, relative to other storage solutions, it's quite a bit more pricey.

 

19 minutes ago, Rider1200RT said:

 

I am surprised that your system doesn't switch off the main circuit to your house from the street in order to avoid killing a worker.

 

 

Those are internet pictures, not my home.  We do have solar but not the Tesla's as of yet.  In a power out, solar kicks off feeding the grid so as not to fry any linemen.

 

My limited reading of the Teslas are size and capacity.  If I'm understanding correctly, for proper sizing of my house, it's a minimum 24hr backup on battery and with the tied in solar, much longer (on good days).

 

With the Tesla's, and our power consumption, we estimate about seven year return.

[Rider1200RT]

Oh Ok Got it!^

[realshelby]

3 hours ago, Sonor said:

 

One last thing - water cooled vs. air cooled and run time.  Ours is air cooled and has no expected run time.  In other words, our neighbor just got a Generac installed and said his has to turn off every 16 hrs. to cool down, not the Briggs.  Not sure if a water cooled will also have that same requirement ...

 

I hope this helps.

Your neighbor has been misinformed. Barring a problem with low oil pressure or running out of fuel, a Generac will run continuously. Air or water cooled. Any generator should run without overheating for as long as it has fuel and oil. There may be oil life related shut down events, but those are hard to reach. 

[steve.foote]

Mike, we deal with the occasional power outage here in our rural setting.  The longest was about 4 days after hurricane Michael, but most last only a few hours, if even that long.  For us, the consideration became more focused on best bang for the buck.

 

Sure, it would be nice to have a standby generator running on natural gas that is supplied via a public utility or a huge tank.  But, that's expensive considering the few times we've actually needed backup power (roughly a half dozen times over the last decade.  If you consider the cost per running hour, a standby generator is ridiculously expensive.  Silly expensive, actually.

 

We utilize two 6500w portable Generac generators (we have two separate electrical panels we wish to power, otherwise one would be sufficient) to power everything we need save for electric heat, were that needed.  They cost about $500 each and the wiring we needed to quick-connect to our electrical panels added about $150/generator.  A reasonable standby generator will be close to $10k installed, and considering the few times it would be used, the savings buys a lot of high-quality single malt Scotch.  And, I'll hook up an electrical cable, flip a couple of circuit breakers, and manually pull start a portable generator for free Scotch.  :-D 

[Rougarou]

3 minutes ago, RightSpin said:

Mike, we deal with the occasional power outage here in our rural setting.  The longest was about 4 days after hurricane Michael, but most last only a few hours, if even that long.  For us, the consideration became more focused on best bang for the buck.

 

Sure, it would be nice to have a standby generator running on natural gas that is supplied via a public utility or a huge tank.  But, that's expensive considering the few times we've actually needed backup power (roughly a half dozen times over the last decade.  If you consider the cost per running hour, a standby generator is ridiculously expensive.  Silly expensive, actually.

 

We utilize two 6500w portable Generac generators (we have two separate electrical panels we wish to power, otherwise one would be sufficient) to power everything we need save for electric heat, were that needed.  They cost about $500 each and the wiring we needed to quick-connect to our electrical panels added about $150/generator.  A reasonable standby generator will be close to $10k installed, and considering the few times it would be used, the savings buys a lot of high-quality single malt Scotch.  And, I'll hook up an electrical cable, flip a couple of circuit breakers, and manually pull start a portable generator for free Scotch.  :-D 

 

That's sort of my current set up, but a single 6500 watt Generac.  It runs to a transfer switch that hits everything but the water heater, twin stoves, pool pump and two HVAC units.  The rest of the house is fully powered up.  A tank last roughly nine hours on the power that we use.

 

But if I eventually go with the Tesla's, I'll be solar during the day, battery at night and feed the grid any excess......which for us and our limited power consumption would be quite a bit.  In our current solar/grid system now, we have no electric bill in the summer, the spring and fall are $10-20ish and the harder winter is $50-75, your prices may vary. 

[Mike]

2 hours ago, RightSpin said:

Mike, we deal with the occasional power outage here in our rural setting.  The longest was about 4 days after hurricane Michael, but most last only a few hours, if even that long.  For us, the consideration became more focused on best bang for the buck.

 

Sure, it would be nice to have a standby generator running on natural gas that is supplied via a public utility or a huge tank.  But, that's expensive considering the few times we've actually needed backup power (roughly a half dozen times over the last decade.  If you consider the cost per running hour, a standby generator is ridiculously expensive.  Silly expensive, actually.

 

We utilize two 6500w portable Generac generators (we have two separate electrical panels we wish to power, otherwise one would be sufficient) to power everything we need save for electric heat, were that needed.  They cost about $500 each and the wiring we needed to quick-connect to our electrical panels added about $150/generator.  A reasonable standby generator will be close to $10k installed, and considering the few times it would be used, the savings buys a lot of high-quality single malt Scotch.  And, I'll hook up an electrical cable, flip a couple of circuit breakers, and manually pull start a portable generator for free Scotch.  :-D 

Our situation is a bit different. We are not at this place most of the time, and often travel out of the country. I do have one portable generator that I can use in the way you mention, but we'd have to be there at the critical point in time. It's a bit of a conundrum, ain't it? This would clearly be some pretty expensive insurance...and we've been lucky so far...but with old age comes nervousness.

[roadscholar]

I'm in a different boat (with different weather) but when there's a hurricane, and there have been a couple doozies the past few years, I put a small window unit in the living room and upstairs bedrooom and run a Honda 2000i to each. Only use part of the house, I have the gens for camping anyway and the oddball windows accept the AC's perfectly. Ice for the perishables  

[Skywagon]

hey mike...beautiful home...After our first year here and many outages, we decided we needed a generator.  We went with a 30kW from Cummings.  Runs on LP or Natural Gas.  We went with Natural Gas.  It served us well during the two hurricanes we've now experienced since we moved here.  The house is 5500 sq ft, will run all of the house including 2-5 ton air conditioners and 1-3 ton.  We over bought on purpose.  They sized it at 20, said pick essential power..nope...want it all all the time.  During Ike it ran 11 straight days.  During Harvey it ran off an on as power was flaky but not really out.  It is instant on.  It's powering out before the lights can go dark.  I think we paid about $10K for the unit...some more for transfer switches...and some more for a slab and plumbing into the gas line.  I suspect I was maybe $13-14K all up all in.  Yep that was a lot, but when its 100 degrees 100 percent humidity and the power is out....is sure is nice to have.  I pay about $150/year to have it fully serviced.  No testing at all or running unless needed.  The unit is very similar to this one...Quiet ConnectTM Series RS30 by cummings

 

[tallman]

Steve, Bill, yes, similar approach.

Window unit in our small trailer keeps sleeping great.

Can put in window of a room and use that way too.

Otherwise, run a fan and an ice maker.

Ice is a luxury 5-7 days into it...

[Stir]

Our solution, grid tied battery backup

 

 

[Stir]

On 2/21/2019 at 7:05 AM, Rider1200RT said:

 

I am surprised that your system doesn't switch off the main circuit to your house from the street in order to avoid killing a worker.

 

 

They run a sub panel and don’t drive the main panel.

[Paul De]

Great conversation as my wife and I are getting ready to downsize to our place in Northwoods Wisconsin and have a similar need for back-up electricity from time to time.  I particularly worry in the Winter as we keep the place open year round.  With the new HE furnaces they need power and Sub-Zero temps would take out the water pipes quickly.   I was leaning toward LP powered a stand-by generator, but might consider solar if it would run everything as needed including A/C.  We need it most when not there and  traveling to warm climates in the dead of winter, so it must be an automated cut over system. I am concerned about the long term cost of ownership with solar,  replacing geriatric batteries, solar panel life span and the warm space to keep all these batteries and controller.  Stanby generators are likely to remain functional for decades with a few oil changes hear ant there.

 

I currently have a 7Kw portable generator for our sub pumps, frig, freezer, a few lights and furnace in the in our MKE place, with a manual switch panel to take these   circuits onto the generator when needed, It works for the necessities but not everything...no A/C, oven, or cooktop. At least not all at once!   It is alsoPITA to drag that out of the corner of the garage, connect the power lead up when power goes down, particularly at night and the wife would not deal with any of it in any case. And it is too loud!!!

[Mike]

Nine months or so after tossing out the question, we now have a backup generator, a 22 kw Generac that is fueled by LP. The company that installed it has installed hundreds of this very model, many at AT&T cell towers. The generator ties into our system just downstream of the utility feed to our property. Once we settled on the contractor and the generator, the only question was whether to run it off of our existing LP tank or install a second one. We opted for the latter...our coop offers used tanks for a song, and the added capacity will give us a good cushion in the event of an extended outage.

 

Thanks to all who shared their insights. 

[TEWKS]

Greatest thing with the new BMWST site is I can “me too” you like, right now.  We’ve had this 14KW since 2012 with zero issues. (now you done did it)  I can run the entire house with no issues. Oh, the one issue, the power hardly ever goes out after the install. 

 

[Mike]

16 minutes ago, TEWKS said:

Greatest thing with the new BMWST site is I can “me too” you like, right now.  We’ve had this 14KW since 2012 with zero issues. (now you done did it)  I can run the entire house with no issues. Oh, the one issue, the power hardly ever goes out after the install. 

 

 

We haven’t had many extended outages, but the possibility of that occurring—and the potential damage—motivated us to finally take the plunge. We were in our cabin earlier this summer when the power went down on a clear day. The cause? An ant got into our smart meter and fried the circuit board, shutting us down completely.  Had we not been there at the time, we might not have discovered it for days. 

[Mike]

One other note: we sited this at the point where our utility feeds into our property’s main panel, behind our barn. Since it’s about 200’ from our cabin, noise won’t be an issue. In rural settings one perhaps has a little more flexibility with regard to placement.