Thoughts on additional power walls

[gpez]

Never said free

I mean, you did:

Had my generator a year and zero cost to maintain so far.

But then you say it hasn't been zero cost since you've been running biweekly maintenance cycles, which consume fuel.

$250/year is not 0 was only my point. Generators need to run maintenance cycles which consumes fuel, have oil changes, have starter batteries replaced, replace coolant or air filters, get inspected/tuned up, etc. Powerwall is literally $0 and 0 time to maintain.

Really trying not to start a snark fest or be overly pedantic here but you're talking a lot in absolutes that frankly aren't. A generator may be low maintenance or the maintenance expense may be worth the benefits but that doesn't make it 0.

 

[BGbreeder]

My tank is 500 gallons. Now, for me, when I use the generator, I do NOT keep it running 24/7.

You are lucky enough to live in a place where it rarely goes below 32F. Just as a reminder, lots of folks here aren't so lucky, and might want/need generator backup during a winter storm. Tank sizing gets to be a real issue for cold weather use.

It is great that you are able not to run your generator 24/7. Not everyone is so fortunate, e.g. my neighbors who have health issues that require constant power.

FWIW: (check your own manual first!) Generac recommends an oil change (and filter) at the end of the first month/20 hours of use, and at least annually/150 hours of use thereafter, whichever is sooner. Some techs recommend every six months/100hours of use. I'm not saying it is a big cost, but most generator owners want their generator to step up and just work when the chips are down, so it would seem to be prudent. I think it is also required for the warranty. In the old ounce of prevention mode, it is also a great time to check that insects haven't filled the air filter, or mice haven't set up residence.

All the best,

BG

 

[h2ofun]

You are lucky enough to live in a place where it rarely goes below 32F. Just as a reminder, lots of folks here aren't so lucky, and might want/need generator backup during a winter storm. Tank sizing gets to be a real issue for cold weather use.

It is great that you are able not to run your generator 24/7. Not everyone is so fortunate, e.g. my neighbors who have health issues that require constant power.

FWIW: Generac recommends an oil change (and filter) at the end of the first month/20 hours of use, and every six months/100hours of use thereafter, whichever is sooner. I'm not saying it is a big cost, but most generator owners want their generator to step up and just work when the chips are down, so it is prudent. I think it is also required for the warranty. In the old ounce of prevention mode, it is also a great time to check that insects haven't filled the air filter, or mice haven't set up residence.

All the best,

BG

Yep, my installer does what ever needs to be down for warranty.

Yes, we are all different. one size does not fit all. And most folks do not have unlimited money to spend

 

[Lloyd]

When you have powerwalls and solar, you only need to use the generator to charge the batteries until the solar can take over and fully charge the powerwalls. This is usually only an hour or so to get the powerwalls from a minimum level say 10% to 25%. This is a minimum use of propane/gas/diesel.

 

[h2ofun]

When you have powerwalls and solar, you only need to use the generator to charge the batteries until the solar can take over and fully charge the powerwalls. This is usually only an hour or so to get the powerwalls from a minimum level say 10% to 25%. This is a minimum use of propane/gas/diesel.

My generator will not charge my batteries

 

[jjrandorin]

When you have powerwalls and solar, you only need to use the generator to charge the batteries until the solar can take over and fully charge the powerwalls. This is usually only an hour or so to get the powerwalls from a minimum level say 10% to 25%. This is a minimum use of propane/gas/diesel.

Generators are not configured to charge powerwalls in any grid tied setup we have heard about here. We have read that it might be possible for the generator to be in the position of "the grid" in a fully off grid setup, but in a regular grid tied setup the generator never sees the powerwalls, so cant charge it.

==============
moderator note: the thread topic is adding additional powerwalls. I am not moving the "generator" discussion out of this thread, but further discussion on generators vs powerwalls should be directed to the existing thread for that topic, which is here:

batteries vs generator

I had a solar guy comment back to a comment I made which was "When I was trained in the energy industry long ago, the rule was “Batteries are best suited for small amounts of power over long periods of time. And generators are best suited for lots of power over short periods of time.” Still a...

teslamotorsclub.com

 

[charlesj]

... We cannot take our money with us, so why not. ...

I take it wherever I go now.

 

[charlesj]

My generator will not charge my batteries

Have you checked what the output frequency of that generator is? My older gasoline generator outputs 63 Hz.

 

[Lloyd]

Generators are not configured to charge powerwalls in any grid tied setup we have heard about here. We have read that it might be possible for the generator to be in the position of "the grid" in a fully off grid setup, but in a regular grid tied setup the generator never sees the powerwalls, so cant charge it.

==============
moderator note: the thread topic is adding additional powerwalls. I am not moving the "generator" discussion out of this thread, but further discussion on generators vs powerwalls should be directed to the existing thread for that topic, which is here:

batteries vs generator

I had a solar guy comment back to a comment I made which was "When I was trained in the energy industry long ago, the rule was “Batteries are best suited for small amounts of power over long periods of time. And generators are best suited for lots of power over short periods of time.” Still a...

teslamotorsclub.com

My intent is to be off grid.

 

[h2ofun]

My intent is to be off grid.

Looking forward to seeing the details on how you can legally do this. Plus, if you can do a technical process where a generator charges batteries, what equipment is used.

 

[Lloyd]

Looking forward to seeing the details on how you can legally do this. Plus, if you can do a technical process where a generator charges batteries, what equipment is used.

Tesla recommends Three Generators:

Kohler RESA 8 kw to 20 kw
Kubota GL series
Himoinsa HYW single phase series

 

[h2ofun]

Tesla recommends Three Generators:

Kohler RESA 8 kw to 20 kw
Kubota GL series
Himoinsa HYW single phase series

And Tesla says these can power powerwalls?

 

[Lloyd]

And Tesla says these can power powerwalls?

Yes, I have an off grid planning and installation guide I found online. It is marked with an NDA so I can't post it here.

 

[Southpasfan]

In terms of the initial question, although PWs and generators both will power the house during an outage, otherwise they are different.

Its fine for a generator to sit there. My understanding is its not good for a PW to sit charged all the time.

So when you get PWs, you use them. I use mine so that I use all the solar I generate and as little of gird provided partially carbon energy as possisble.

Other posters use them so that they never buy any expensive energy during peak periods because their utility screws them over.

Other than storm-watch mode, no one in the US charges their PWs from anything other than the sun.

I don't know if anyone who runs their generator every night just to avoid buying electricity from a utility. There are, of course, true off grid people who may run generators routinely but generally that is not who posts here.

So, you might pay, say $10k for a generator set up that you intentionally hardly ever use. And when you use it, unless generator kwh are insanely cheap you are not going to use it to charge PWs, that's for sure.

So:

Generator (costs what it costs) = true back up system/not really aimed at either rate arbitrage or being environmentally friendly in the slightest.

PWs. (cost what they cost) = true back up system to the extent of their capability/allow daily rate arbitrage/allow you to use your solar at all times of day, without using environmentally dirty energy at night.

So that means, unless you have a really, really small energy footprint one PW is not really sensible. Its not enough for significant back up, but one PW would get you through the peak period rip off every night, that's true.

Two or more PWs, are really the way to go IMO for how they are used.

 

[Lloyd]

If I design my system properly the Generator should not ever have to come on. It requires enough generation from solar and enough storage from the powerwalls to power your microgrid. There are off grid systems in Colorado I am told that use powerwalls that can charge from generators where grid power is not available. The generator is only used say when your powerwalls are depleated to 10% and then turns off when the level gets to 25%. Thus maximizing the power you use from Solar.