I can’t answer your question about efficiency without asking a whole lot of questions.
Forgive me but why generator at all?
I was lead to believe that a good generator run properly would produce power at a lower cost than my public utility.
Are you worried about not having enough batteries?
Yes, in the short run, 1-5 years. No in the long run.
Not enough Solar to charge them?
I don't know yet. I currently have 5KW of solar and no grid tie or batteries. My energy bill is still $250 per month. I use a lot of power.
With the changes I'm making I expect a radical change in my power costs.
With your off peak rates so low you could use utilities to charge battery unless you just want them out of the picture completely.
That is the plan, for this next version of the system. As soon as I go off peak rates, switch from battery draw to utility.
My array is designed for winter and I over produce in the summer.
Mine is presently limited to what I draw. Since I have more draw, I can ask for more solar. Once I go from 20 to 50 solar panels I plan to increase my draw: electric car, electric lawn mower, electric snow blower, etc.
Then more panels, but once I hit 20kw the programs for the utility and insurance change. Maybe not terrible but I have no experience with them yet.
you got an insanely low off peak rate. You can never compete with a generator with that.
Just buy enough batteries - charge during off peak and call it a day.
That is the present plan based on this news that generators are not great.
a $2000 generator will never last 25 years, be happy if it's last 5 years. You need to change the oil every 100 hours, and lots of other stupid maintenance. Do you want to buy a hobby? Are you bored?
I estimate in the summer if I have 2 days of battery power on hand that it would run perhaps 2 - 4 hours per month.
In the winter, probably more like: 8 - 10.
With that use I would expect 1 oil change per year.
Is this a hobby: yes
Am I bored: No, I have a hobby
.
You need to spend like $10-15k for something which lasts 25 years.
Great input, thx, perhaps it's also that range of cash to acquire a generator that is $0.08 / kwh efficiency?
I was doing this calculation once for my 5500W Onan generator, which needs 1/2 gallon with no load and 3/4- 1 gallon per hour at full load.
Getting about 5kw/h into the batteries per hour. so it's 1 Gallon for 5kwh.
It's not really something I would be recommending permanent. 60cents - $1 per kw/h It's very expensive to run that thing.
Just so that you know 1 gallon is roughly 33kw/h. It might have made sense when gasoline was a $1.5 but not in $3-4 times.
I appreciate the information. I keep hearing people talk about gas or diesel. I have a little 120v gas generator. I've never calculated the $/kwh because the cost was more about losing food (refrigerators, I have 6), and communications / internet.
I am only interested in natural gas because I have a pipe feeding my home. I would never recoup the time it takes to go get gas regularly. That is not a hobby I'm interested in. As it stands I'm taking out all the gas powered stuff and replacing it with electric so I can spend more time with the electric hobby I enjoy.
I wondered if this one natural gas powered engine was the one that would provide freedom from the grid. From what I'm hearing so far, it is not efficient enough to do so.
