Confused on PTO generator size

[gogojuice]

I just looked and took the survey over at Generac. According to its survey… I need in the range of 20 kw - 27 kw for my house. That seems like a lot to me, but I have no experience with being off the grid and looking at alternative power. I have just dealt with the power outages. Is it fair to say that the standby generators would require more maintenance but would be easier to use?

Appreciating your replies

 

[MacTractor]

I am in the process of working this out right now. My plan is to use a manual transfer switch but as my
basement is finished the area of the panel is not large enough to accommodate a transfer switch.

I am looking at the Generlink product which just plugs into the meter base but I am sure it will be fun getting this approved with NB Power.

Only other option would be an external transfer switch which could be very costly.

How does the generator connect to the transfer switch ?

 

[MacTractor]

Don't get me wrong, my preference would be the Generac unit as well but I really can't justify $5K + for something that may not happen again for a couple of years. If I had outages on a more regular basis, I would do it. For me I would need to expand my propane storage capacity as I can't get delivery once the winter starts due to the steepness and length of my driveway. Again lots of costs so I am trying to mitigate the possibility in a reasonable manner which will be a $1600 PTO generator and maybe a $1K switch. I would bet your setup would be close to 10k here for me in NB.

When I went through this a few years ago we went with a Generac 20kw standby generator. Best decision I ever made(after the wife). It came with the transfer switch and powers the whole house, everything! We have Geothermal heat, well, electric stove. You start adding all the 220 loads and it was easier and made sense to power it all. I have no complaints on the Generac generator. good product. When it is cold, blowing and generally nasty, I do not have to go out and get the tractor. Another factor is when I am not home it still works. My wife does not have to try to hook up a PTO and get it set up if I am gone. It is a set and it is always ready. IMHO the best way to go. I bought mine at Farm and Fleet here in Iowa. It was $4200. I spent another $1000 with the electrician and the propane co to run a new liquid line and regulator. Cheap insurance.

 

[brin]

I will just add this note....We have only had 2 power outages that lasted 3 and 4 days in the last 30 yrs. or so....but a few that last an hour to a few hours....So I bought the PTO genny 3 yrs. ago...I have not had a power outage since I bought it....so one way to never have a power outage seems to be to buy a generator....I run it under load once a yr. just to keep up but I think I would not be too happy if I had spent thousands of dollars...:2cents:

 

[buickanddeere]

The Gener-link is the among the simplest and economical methods to power the entire electrical service with up to 10 or 12.5KW of power. Even includes a 20ft power cable. Max rating is 40amp per line. Probably the easiest unit to satisfy electrical inspectors with too.
The sliding interlock bolted onto the face of the existing breaker panel is probably the cheapest if there is a way to run power from inside to outside the house. More capacity possible too above 40amps.

 

[Soundguy]

I will just add this note....We have only had 2 power outages that lasted 3 and 4 days in the last 30 yrs. or so....but a few that last an hour to a few hours....So I bought the PTO genny 3 yrs. ago...I have not had a power outage since I bought it....so one way to never have a power outage seems to be to buy a generator....I run it under load once a yr. just to keep up but I think I would not be too happy if I had spent thousands of dollars...:2cents:

i hear ya.

I bought my 12.5k unit in 04 right before the bad storms. used it 04/05.. one outtage over a week. and then used it at the farm for the well while waiting for power. past that it has had an easy life. has done some welding hooked to a carry-all on a palate that and a buzz box welded.. drove around to where needed. but again. not much use. kind alike insurance. get it.. then don't need it.

 

[bcp]

The Gener-link is the among the simplest and economical methods to power the entire electrical service with up to 10 or 12.5KW of power. Even includes a 20ft power cable. Max rating is 40amp per line. Probably the easiest unit to satisfy electrical inspectors with too.

I just recently checked with our power company. They don't allow it.



Bruce

 

[buickanddeere]

I just recently checked with our power company. They don't allow it.



Bruce

That is a shame. Then your utility wonders why it has a higher than normal infestation of jackleg electricians that back feed 120/240 generators into welding receptacles.
Does the utility offer a turn-key transfer switch package ?

 

[daybreak1998]

I just recently checked with our power company. They don't allow it.



Bruce

Howdy,
If the Generlink product is not allowed, then look over the options from PSP Products Transconnect.

 

[grsthegreat]

uietRe: Confused on PTO generator size

I dont have in front of me your load calcs or what appliances you HAVE to run as opposed to what you want to run. I install lots of generator systems for people, and youd be surprised how small some units need to be.

My house is supplied by a 7.5KW fixed propane unit. It powers up all upstairs lights, garage door openers,all tv and entertainment, refer, freezer, gas furnace (fans, ighniters) and gas water heaters. I got rid of my electric range top and electric water heaters and installed propane units so i didnt need as large of a generator.

I am only using a little over 1/2 of my generators output at this load.

I have a manual transfer panel so i dont have to worry about switching off the heat pump, a/c etc. My generator only powers up the panel i want powered up.


Now for the bad news. I want to add my barns power load (fed from house panel) and my now completed basement off of the generator. But this will overburden my 7.5 kw unit. Im looking at installing a 14KW Generac ($2,800) and also looking into the newer QuietSource Generac liquid cooled units ($7,500). This will power my entire house and barn (has 4 heated horse waterers).

A 14 KW generator will power LOTS of stuff. Ive installed many of these sized units in custom 4,000 SF homes and have had no issues. Most of my clients dont want an automatic transfer switch as there vacation homes, and dont want them running if there not home.

In the OP's case, depending on what panel you have in the house, there are MANY different manual transfer options available that can cost under $80.00 to instrall

A full scale automatic transfer switch CANNOT be adapted to run a pto generator, as they need constant input of power and 12v battery relay from generator to operate.

 

[gogojuice]

I'm not sure what type of panel is in my basement. I know its 200 amps though. As I don't see myself getting a bigger tractor any time soon. It's not needed on this property 2 acres, cleared and in good shape. I'm thinking that a 12-15 kw may be overboard if I can only produce about 7.5 with the bx. Then perhaps I should be looking at the 10 kw versions.

I think this is my first job to get sorted out. The size that I can honestly use. I believe that I could tailor my needs to what power I was able to produce?

For looking at various sites, there seems to be a wide range of how many kw I would need.

Does anyone know of an honest / good one?

As I said.. I'm not knowledgeable on this topic… so… this may be a dumb question, but if my furnace and water heater are natural gas does that lighten the load?

 

[aczlan]

I'm not sure what type of panel is in my basement. I know its 200 amps though. As I don't see myself getting a bigger tractor any time soon. It's not needed on this property 2 acres, cleared and in good shape. I'm thinking that a 12-15 kw may be overboard if I can only produce about 7.5 with the bx. Then perhaps I should be looking at the 10 kw versions.

IMO, it depends on if you are buying new or used. If buying new, I would go with a 10kw one as its a standard size and resale should be easier. If buying used, you might get a better deal on a larger one.

As I said.. I'm not knowledgeable on this topic so this may be a dumb question, but if my furnace and water heater are natural gas does that lighten the load?

Quite a bit.

Aaron Z

 

[Soundguy]

the btu comes fromt he gas. pilot and control electroncs are easy.

in an emergency. all you may really need is water and refer.

I know in times of extended outtages.. to conserve fuel. we only powere dup every 4 hours to run the refer for an hour, and pump up the well, then alternator over to using the water heater to heat the load pumped up. with being carefull of openingthe fridge only when needed. you can run a house at emergency level for a week on 10g of fuel... environmental controls were off... so when it's hot.. yer hot. when it's old.. you bundle up..e tc.

 

[grsthegreat]

I'm not sure what type of panel is in my basement. I know its 200 amps though. As I don't see myself getting a bigger tractor any time soon. It's not needed on this property 2 acres, cleared and in good shape. I'm thinking that a 12-15 kw may be overboard if I can only produce about 7.5 with the bx. Then perhaps I should be looking at the 10 kw versions.

I think this is my first job to get sorted out. The size that I can honestly use. I believe that I could tailor my needs to what power I was able to produce?

For looking at various sites, there seems to be a wide range of how many kw I would need.

Does anyone know of an honest / good one?

As I said.. I'm not knowledgeable on this topic… so… this may be a dumb question, but if my furnace and water heater are natural gas does that lighten the load?

furnace and water heater are usually the largest loads on residential units. An electric furnace can add 80-120 amps (20 - 30KW) to a system. The average water heater can easily use 5,000 - 6,000 watts.

Using gas fires furnace and water heaters would only make a small demand on the generator....like maybe 1 amp (100 - 200 watts) for fan and controls.

 

[MikePA]

I'm not sure what type of panel is in my basement. I know its 200 amps though. As I don't see myself getting a bigger tractor any time soon. It's not needed on this property 2 acres, cleared and in good shape. I'm thinking that a 12-15 kw may be overboard if I can only produce about 7.5 with the bx. Then perhaps I should be looking at the 10 kw versions.

No offense, but focusing on the generator is going about this backwards.

1. List the appliances, lights, devices, you must run, in all seasons of the year.
2. List the appliances, lights, devices, you want to run, in all seasons of the year.

This is no more complicated than walking around the house, yard, garage, etc., pretending the power is out and making a list.

3. Map every item on your list to a circuit in your breaker box, noting the voltage and the amperage of the circuit.
4. Total the 110v circuits and the 220v circuits and associated amps.

A spreadsheet works really well for this exercise.

5. Sit back and review the list. You will probably end up moving your "musts" and "wants" around.
6. Note any circuits that have to be on at the same time.

With this information, you'll be able to look for a generator and transfer switch.

One of the nice features of my automatic transfer switch is it does automatic load balancing between all the circuits and allows me to identify, by circuit, whether it can be load balanced, minimum on time, minimum off time, etc.

 

[Gary Fowler]

No offense, but focusing on the generator is going about this backwards.

1. List the appliances, lights, devices, you must run, in all seasons of the year.
2. List the appliances, lights, devices, you want to run, in all seasons of the year.

This is no more complicated than walking around the house, yard, garage, etc., pretending the power is out and making a list.

3. Map every item on your list to a circuit in your breaker box, noting the voltage and the amperage of the circuit.
4. Total the 110v circuits and the 220v circuits and associated amps.

A spreadsheet works really well for this exercise.

5. Sit back and review the list. You will probably end up moving your "musts" and "wants" around.
6. Note any circuits that have to be on at the same time.

With this information, you'll be able to look for a generator and transfer switch.

One of the nice features of my automatic transfer switch is it does automatic load balancing between all the circuits and allows me to identify, by circuit, whether it can be load balanced, minimum on time, minimum off time, etc.

While tallying up these circuits remember that not many circuits are required to run all of the time so even though you tally up 100 amps you may not need but 1 of the 20 amp circuits at any given time and it wont be pulling 20 amps if your house is wired correctly. You do have to account for any startup load for a large appliance like AC for your Genset needs if you plan to use that equipment but for those you can use the surge amp rating for your generator.

For my house, all electric, to use my central heat would require 100 amps minimum to power the heating elements and to get that I would need a 30KvA minimum, so no HVAC for me nor will I try to power my hot water heater, 9000 watts continuous. If I were into a long period of time without power, I could drop out one of the heating elements and get some hot water if needed, but for short outages, I will just do without the hot water. But I can power the rest of my house using power sparingly and not using oven or over one burner on my range at one time while using my 8000 running watts Generac generator. Most of the lighting is LED so I have no issue with lighting, most cooking is with an electric skillet so that isn't an issue and fridge and freezer wont take a lot of power as they can go for 24 hours without power if doors are kept closed. As for summer time cooling, I have a 110v window AC that I can install in one of the bedrooms and cool only that room at night so I can sleep comfortably. As for heat in winter, I have a portable propane heater that will provide enough heat to keep the house almost comfortable and nothing wrong with wearing a jacket to keep warm, even if power is on, we keep our thermostat at 68f in winter.

 

[MacTractor]

This is exactly what I need but it would appear that is not approved in the Province of NB.....

Will probably end up with a double throw 3 pole switch that is ratd for exterior.

The Gener-link is the among the simplest and economical methods to power the entire electrical service with up to 10 or 12.5KW of power. Even includes a 20ft power cable. Max rating is 40amp per line. Probably the easiest unit to satisfy electrical inspectors with too.
The sliding interlock bolted onto the face of the existing breaker panel is probably the cheapest if there is a way to run power from inside to outside the house. More capacity possible too above 40amps.

 

[daybreak1998]

Howdy,

Generator sizing?
Do you have a well? usual smallest size would be around 6000watt generator

Do you want minimalist living? your on city water? nat gas water heater? you could probably get by with a 2000watt unit

Do you want to have most? around a full 30amp capable generator (7500watt and higher)

Lights in a house are nothing... lights just really do not use much power.

PTO Generator = don't get all caught up in what your tractor puts out. Yes, they say the rule of thumb for tractor horsepower is 2hp for 1 kw power. That is only a very rough idea, to help noobies understand. To be a little more precise, you could use a better formula of 1.82hp=1kw power produced.

10KW PTO generator would be fine, although, for a little more, better AVR capability, and power surge motor starting ability, and less variability with power draw changes. I would rather go for a 15kw PTO unit

15kw PTO generator hook-up
to get the most out of all that available power to your panel, you could use a interlock and double pole 60amp breaker.

AVR= automatic voltage regulation = does just that, it means its going to be more electronic friendly of power.

With any generator, you will want a clean 60Hz cycle, and to keep it on that 60Hz during loads as well. That is the most important part of power from the generator. 60Hz and 110-130volts

PTO Generators = smaller units have internal mass rotation of 3600rpms (internal 2-pole alternator) while larger units will spin at 1800rpms (internal 4-pole alternator) This is part of the reasoning of gear box translation from tractor 540rpm PTO through the gearing to make the correct 60Hz power.

PTO generator = Need to use your tractor to power it. OK, How much yard cleanup are you gonna have? how much snow is gotta be moved? 3-4 hours? OK, now hook up the generator and make power

 

[gogojuice]

Thanks for all the info.. I have a kubota bx 2670 so thats about 19.5 rear pto. (not changing the tractor or property 2.0 acres cleared… this is the retirement home)

I would like to keep the house with as much power as possible, keeping in mind cost and limitations of the tractor and my appliances.

Mike I know you suggested not looking at the generator… but I think I would get the one that is the biggest for the tractor, so that takes care of that factor. I can't produce more than my tractor. I was hoping that I would be able to power the whole house and not have to pick certain circuits. Perhaps I was hoping for too much power.

We don't get hurricanes / tornadoes up here that many people get. So clean up is not the issue. For up here it is downed power lines due to snow primarily. Ice storms. We have been fortunate at our place, but further south there are reports of people being without power for about a week. So I don't think yard clean up is an issue. Perhaps clearing the driveway after the snow has stopped (2 hrs approx)

My house setup:

- Natural gas water supplies. (water heater / furnace / fireplace)
- Well water and water softener
- Fridge
- Freezer
- Microwave
- Electric stove
- Electric washer / dryer
- Electric dishwasher
- Air Conditioner (not sure what size.. its buried under snow right now)
- Pool 18x36. (not sure on equipment. it's snowing lol)
- Various electronic items

These are all the power hungry items I can think of. I have no idea what I could run from that list. Things would change as the seasons / circumstances dictate.

Hope that adds a bit more info

 

[batwing]

We have a 6000 watt gen with a 11 hp. gas engine we bought 6 years ago when power was going to be off for several days. We ran everything in our house except electric stove including window air conditioner,(have gas water heater) done great on gas. I put sea-foam in it and let it run all the fuel out of carb, let set for 4 years before it was needed again. not a lot of money, Happy Happy Happy!!!

Ron