Off-grid standby generator

[ColoradoRider]

I've been looking through this forum and I haven't found a thing on this topic. I'm fat, dumb, and stupid when it comes to all of the ins and outs of solar power, but the one thing that I'm sure of is that if I don't plan for the worst case scenario it is guaranteed to happen. I'm building a 4.4 kw system with AGM battery back up. I had to go AGM due to the uber high cost of the good lithium batteries. I am putting this all together at my "retirement home" which sits at 9400 feet on the western flank of Pikes Peak here in Colorado. With almost 6 hours of sunshine per day, I shouldn't ever have a need for a standby generator (or so I think). Still though, having one would give me a good deal of peace of mind.

Due to the high altitude of my future home, most generators lose a substantial amount of power production (or so I have been told by some pretty knowledgeable peeps). I'm really into overkill, but there are limits to my wallet, so I'm trying to be practical. I've been looking at Generac's in the 10 Kw range, but I don't want to limit myself to one brand. So, the question is, what generator currently on the market would you all recommend?

 

[John Frum]

If I had a solar system I personally would not go with a standby generator.
I would start my generator manually as required to top up the batteries.
If the sun cooperate and you need to charge batteries fire up the generator for ~5 hours during the day.
Enjoy peace and quiet for the other ~19 hours.

Maybe a fuel injected generator would cope better with the altitude.

https://powerequipment.honda.ca/generators/ultra-quiet-7000i-es

7000 Watt Electronic Fuel Injection Generator - RYOBI Tools

7000 Watt Electronic Fuel Injection Generator

www.ryobitools.com

On the other hand storing gasoline is a pita.
You are probably just going to have to de-rate for altitude.
Do you have natural gas available?
How about propane?

 

[ColoradoRider]

On the other hand storing gasoline is a pita.
You are probably just going to have to de-rate for altitude.
Do you have natural gas available?
How about propane?

The nearest neighbor is about 2 miles away, but I don't want a noisy generator. It has to run on propane since that is the only non-solar power source I'll have available. My hope is that the generator will only come into play when we have the odd times where it is cloudy for a week at a time and the solar system struggles to produce enough energy to support our needs.

I'm planning on having everything in place by the middle of June so that when it comes time to start nailing sticks together we'll have all the power needed.

 

[Steve_S]

I'm OFF GRID and Solar Powered and have two gensets, the main backup one is 7.2/9kw.
I hear exactly where you are coming from, a lot of us around here are solar powered offgrid and a common Genset I see off gridder's using now up here is the Champion Stand-By Gensets. My Gennies are Champions and never ever had a lick of trouble with them (hundreds of hours on them). They also can't be beat for Bang for Buck. They sometimes come on sale at TSC (Tractor Supply) for an really super price but shop them around. One thing though, I am anal when it comes to maintaining my equipment and the gennies ONLY see 0W50 Synthetic Oil and get regular maintenance runs & cycles. (I'm in the deep north, can be snowed in for DAYS and my life can depend on extra emergency power if needed, so no chances) 1st rule of Crisis Management is Prevention and 2nd rule is planning (backups).

Home Standby Generators – Champion Power Equipment

A Champion home standby generator provides peace of mind, security and convenience for your family during an emergency by automatically powering the essentials or your entire home.

www.championpowerequipment.com

 

[John Frum]

The nearest neighbor is about 2 miles away, but I don't want a noisy generator. It has to run on propane since that is the only non-solar power source I'll have available. My hope is that the generator will only come into play when we have the odd times where it is cloudy for a week at a time and the solar system struggles to produce enough energy to support our needs.

I'm planning on having everything in place by the middle of June so that when it comes time to start nailing sticks together we'll have all the power needed.

Ok looks like propane and de-rating accordingly is the way forward.
Its my understanding the residential standby generators are only good for about less than 1000 hours.

 

[upnorthandpersonal]

I use an ATG Multifuel which can run on diesel, heating oil, vegetable oil (canola oil, sunflower oil, corn oil, soy bean oil, etc.) and cleaned waste vegetable oil.

 

[namesgolden]

~3500w inverter based dual fuel generators are obtainable for $1000 or so. they'll probably be closer to 3000w on LP at altitude.

 

[ColoradoRider]

~3500w inverter based dual fuel generators are obtainable for $1000 or so. they'll probably be closer to 3000w on LP at altitude.

Yep, but is 3kw enough to charge batteries AND allow me to maintain a solar-normal lifestyle? I think I need just a little bit more juice than that. Is 10kw overkill?

 

[ColoradoRider]

I use an ATG Multifuel which can run on diesel, heating oil, vegetable oil (canola oil, sunflower oil, corn oil, soy bean oil, etc.) and cleaned waste vegetable oil.

I have NO idea what you are talking about, but it kind of sounds like one of those old military vehicles that were advertised as running on anything shy of water. They could run on all those types of fuels, just not very well.

 

[upnorthandpersonal]

I have NO idea what you are talking about, but it kind of sounds like one of those old military vehicles that were advertised as running on anything shy of water. They could run on all those types of fuels, just not very well.

This one: https://www.atg-germany.com/atg-multifuel-3sp/

Runs extremely well.

 

[madmax]

If you were intending on operating an 4.4kw system, a 3500-4000W generator should be more than sufficient.
Lets put it in terms of how much you use in a day, and how much you could generate in a day. I'd figure you'd at least try and use the daily power generated (even if not dipping into the batteries).

6HR*4.4kw=26.4KW production/day. Im going to assume you will use some of this energy as it is generated. Storing all of that will be expensive. Some people do, but I don't know of too many people with 4.4kw storing more than 3-4kw at a time.

As far as generator backup, a smaller more fuel efficient unit running at 75-80% of its rating will be the best power/fuel economy. Think of the power produced as water flowing through the stream.. and then to the battery bank, which is the lake. The lake stores the extra, and can open the "dam" for large power demands.

You can't run those large power demands off a small generator. But a 1200W generator run for 24 hrs a day produces just as much power.

You also have to figure out the inverter/charger type system your going for. Having a generator sized larger than the charger can deliver will also be a waste.

Larger generators however have electric start- and some have electric stop. Some charge controllers have contact starters, so they can trigger a generator to start.

 

[madmax]

saw it, its expensive. kinda like a goal zero.
Won't be buying it though. Its not small enough to be handy for light purposes. It might be useful for some contractor who needs to run some table saws... without the generator noise.