Paging Red Beard ........ generator question

[wdfifteen]

My old house had a 19k Generac. The main panel was 200 amp and the automatic transfer switch was 100 amp with a load shedding switch on the AC. The transfer switch was sized based on the actual electrical load in the house. The circuit to our detached garage was bypassed. The one time we used it the AC ran the whole time the generator was running.

Our current set up is a 13k Generac 60 amp automatic transfer switch with a 16 slot breaker panel. Main panel is 200 amp. All critical circuits are fed off the panel on the transfer switch. That’s basically all fridges, both furnaces, the fan in the water heater, and lighting. When the power goes out we do without AC and power to the out buildings and a couple of lighting circuits.

I didn’t design either system. In both cases we had the Generac dealer look at our needs and make recommendations.

Just letting you know you don’t HAVE to have a 200 amp TS in a 200 amp house.

[red-beard]

The cost of the Generator plus TS is around $4500. $8k is $2500 for install and maybe $1k for profit.

About $1000 for the electrician, $750 for pipe, wire, conduits and gas regulator and the rest is labor for trenching and install.

Cables are 00, 100Amp breaker. Pipe size is 3/4" if you put the regulator at the generator. If the electrical box and gas meter are not close, install goes up. If you need city permits, price goes up. If you need licensed plumber for gas line and certified electricians for conduits, price goes up.

[red-beard]

Originally Posted by wdfifteen

My old house had a 19k Generac. The main panel was 200 amp and the transfer switch was 100 amp with a load shedding switch on the AC. The transfer switch was sized based on the actual electrical load in the house. The circuit to our detached garage was bypassed.

Our current set up is a 13k Generac 60 amp transfer switch with a 16 slot breaker panel. Main panel is 200 amp. All critical circuits are fed off the panel on the transfer switch. That’s basically all fridges, both furnaces, the fan in the water heater, and lighting. When the power goes out we do without AC and power to the out buildings and a couple of lighting circuits.

Just letting you know you don’t HAVE to have a 200 amp TS in a 200 amp house.

If the TS directly feeds the main panel, yes you do! They must match.

If the TS feeds a sub-panel, it can be smaller.

[wdfifteen]

Originally Posted by red-beard

If the TS directly feeds the main panel, yes you do! They must match.

If the TS feeds a sub-panel, it can be smaller.

Edit: On second thought, the TS includes a sub panel in my current house and fed a sub panel at my old place.


The TS basically is a sub panel in my current house, and I believe it was that way in the old place.

[wdfifteen]

rfuerst911sc, I suggest you consider whether you really want the house to "act like you are in the next room" when the power goes off or if you want to do without some items.
According to Tons Of Air Conditioning to Kilowatts | Kyle's Converter a 3 ton AC unit uses 10.5 kw of power. With an 11kw generator you don't have a lot of wiggle room for other things. At the very least you should consider a load shedder on the AC. You should do a whole house power assessment and see what you really are using.

We looked at the cost of an adequate generator to run the whole house and decided to downsize. We listed all the things we could do without in an emergency - AC, car charger, outbuildings, pool heater, dish washer, etc and conferred with our Generac dealer. He suggested a transfer switch with a sub panel than only powered the things we really needed in an emergency. The power goes out about 4 times a year out here and we have been happy to get along with partial power.



The box on the left is the main panel. The center box is the old sub panel to the west part of the house. The box on the right is the transfer switch with all the essential circuits when the power goes out.




The old sub panel still powers the AC, car charger, outside pool pumps, outbuildings, etc. as well as the 60 amp transfer switch sub panel (breaker on the lower right). When the power goes out, these circuits all go dead. It still has the old breakers in it, but they are disconnected.



The transfer switch/sub panel powers the refrigerators, freezers, furnaces, water heater,
lighting, and other things we can't do without. When the power goes out, it starts the generator and provides power to all of these circuits.

[Arizona_928]

Not bad for a days work....

[rfuerst911sc]

I am slowly leaning towards a 20kw and be done . After studying manufacturers websites for size/price/fuel consumption there is not a lot of difference between 12kw and 20kw. Yes the 20 is more up front and a little hungrier with fuel consumption but it's not a huge difference . A 20kw will run my entire house .

But then I start thinking that in a " normal " year we lose the power two times . Some years more and some less. In that scenario I start thinking about what can we do without , can we get creative with load management via breakers and maybe a 12kw either whole house or portable is the way to go . If I would go portable I would still do a transfer switch and buy a duel fuel so it can run off a 250 or 500 gallon tank .

Currently we use our Honda 3000 watt inverter generator with the spaghetti mess of extension cords 😁 . I primarily only keep refrigerator and freezer going so food doesn't spoil and a few lamps. My point being we can go without certain amenities but I prefer not to.

[Evans, Marv]

Patrick's Kyle's Converter says I need 25 kW just to run my seven ton load for my HVAC. That's a lot more than I thought for that basic power need. I've been mulling over a whole house generator for a while & still haven't made up my mind to pull the trigger or just keep with my 10 kW that powers fridge, freezer, & some lights for the few times we're out of power. I was thinking maybe a 20/25 kW diesel, but it seems like I might need to go for 30/35, which is a pretty good sized system.

[red-beard]

Originally Posted by wdfifteen

rfuerst911sc, I suggest you consider whether you really want the house to "act like you are in the next room" when the power goes off or if you want to do without some items.
According to Tons Of Air Conditioning to Kilowatts | Kyle's Converter a 3 ton AC unit uses 10.5 kw of power. With an 11kw generator you don't have a lot of wiggle room for other things. At the very least you should consider a load shedder on the AC. You should do a whole house power assessment and see what you really are using.

a 3 Ton Air Conditioner uses about 3-3.8kW of power. It may need up to 13 kW to START.

This is an older 13 SEER air conditioner, so some newer ones may not require so much current. Check the label on your Air Conditioner outdoor unit.

For Starting, use LRA (Locked Rotor Amps) multiplied by your 220-240 voltage. This is the starting power. With a Generator, the unit may allow up to a 30% voltage sag, which will reduce the starting power.

For running, use RLA (Rated Load Amps). You really should also add the FLA (Fan Load Amps) to the running current. And this data sheet does not show the evaporator and the blower which would be about another Amp or so.

But this will not add up to 10 kW of power.



That "Kyle Converter" is straight up wrong.

[Arizona_928]

+1
One could go to soft start setups; vfd ect. But that adds cost.

I'm a firm believer in manual everything except for the semiautomatics...

I would run a generator interlock for the breaker panel. This is a house, not a research lab, or server farm where if the temperatures rise **** goes boom/ruined.

As for the cheaper buy in price air cooled stuff; while they have a purpose for the average joe that won't run a bunch of hours over the water cooled diesel. If you plan to use the machine to full potential the 12k buy in on a diesel that will run 10k hours over the twin air cooled for a quarter of the price.

[red-beard]

Really Good Soft Starts are not expensive. $245.99

Hyper Engineering | Home

https://shop.gentekpower.com/collections/sure-start-ac-soft-start-ss1b08-16sn-ss1b16-32sn-hyper-engineering

SS1B08-16SN for up to 3 Tons
SS1B16-32SN for up to 6-7 Tons

They also make 120VAC units for RV units.

And 3 Phase units. They work for 50 or 60 Hertz

[Arizona_928]

Hmm those are a really good price!

[Baz]

Even though I'm in Florida and we get our share of hurricanes - and with some of those power outages....I have yet to justify in my mind one of those "house generators".

What I did do is get a portable with electric start that can run off gasoline or propane. It came with wheels and a handle so very easy to move around.

I bought it on Amazon just over a year ago for around $470 and don't believe the same model is available anymore. I moved it to my back patio where it is closer to my refrigerator and window AC - and whatever else I want electric for. And ran it just the other day after not running it for almost a year. The battery was still charged and she started right up with the flick of a switch. Runs pretty quiet too for a gas unit.

I don't mind a few extension cords. Worth the effort to have power to the fridge and AC!

[GH85Carrera]

Baz, I am right there with your way of thinking.

Every generator thread gets me wanting one. Then I realize how much the whole house units cost, and my interest shifts to a Honda inverter unit. Then I get to wondering where do I want to store it, and how much gasoline do I keep on hand and I get lazy and just forget abut it.

My back fence neighbor used to work for the local electric utility. He put in a 12 grand generator that automatically starts and tests itself regularly. He has had it for 9 years so far and he has used it for 18 minutes of backup power. That is some really expensive power.

We don't worry about hurricanes or tsunamis in Oklahoma. The biggest baddest tornadoes came through central Oklahoma. One F5 had 300+ MPH winds and leveled a few hundred feet wide paths of utter destruction. Another one was 2.5 miles wide and moving at nearly 100 MPH across the ground. Neither even made the light flicker in my part of town. The worst damaged areas were just a 1/4 of a mile from full civilization with hospitals and restaurants and gas stations everywhere. So nothing at all like the recent hurricanes and flooding where entire areas are in the dark.

If I happen upon a great deal for a Honda generator, I may buy one, but it is low on my list of to do.

[red-beard]

Since moving to Texas in 2004, we have had the following weather events

Hurricane Rita - 2005 (stronger than Katrina)
Hurricane Ike - 2008 - off for over 4 days
Hurricane Harvey - 2017 - Did not lose power
Great Texas Freeze 2021 - off for 30 hours

We have had numerous outages for random stuff. One of the power-lines feeding the south side of the neighborhood is much worse than the north side.

A few notes on power reliability

99% reliability means your power is off 3 days, 16 hours per year.
99.9% reliability means your power is 8 hours and 45 minutes per year
99.99% reliability means your power is off about 1 hour per year
99.999% reliability means your power is off about 5 minutes per year

The Average in Texas is about 2 hours per year. This is statewide.
The Average in Houston is about 8 hours per year. And this comes from being without power for days, every few years...

[GH85Carrera]

There is an retirement and assisted living center about a 1/2 mile north of our house. I really think they get priority service. In the big ice storm and sub zero freeze from this February we had about 2 minutes of power loss. All of our lines in the neighborhood have underground service.

OGE is our electricity provider. They are rated very highly by the industry and I sure love em.

[Zeke]

When you start figuring the cost of propane tanks you end up realizing you could have 10, 15, 20 twenty pound tanks for less than what a 200, 300 or 400 lb. tank would cost. The price of the fuel is the same.

I think you could figure on having 2-3 generators using the same reasoning. And if one takes a siht, you still have power. I only have a 120v 3000K unit to keep the beer cold. I could have 3 for $1500 and be at 9K potential. They also will pair up if you buy the right ones.

[rfuerst911sc]

Possible interesting twist , a Miller Pro 300 diesel welder/generator has popped up for sale . Have asked seller for details . It is a 2014 model year .

[rfuerst911sc]

Looks like the welder/generator might be a scam . Oh well .

[rfuerst911sc]

Interesting scam . I received an email from the seller last night with several pics of the generator ( or someone's generator ) . The seller provided her name and stated she is currently at Offutt AFB in Nebraska . Ok so far maybe it's legit ....... maybe.

She provides some details including the hours on the meter , then it gets weird/scammy . She asks me to provide my name and address ( red flag ) so eBay can start the process of DELIVERY to me !!!??? She states she made these arrangements prior to her leaving for the AFB . And as a final touch she states her husband passed away two months ago .

I can see how someone could fall for this , but it has warning written all over it to me . Could I be wrong ? Sure . But I am not willing to gamble . Be careful out there guys there are a lot of folks wanting to steal the contents of your wallet .