[RE-wrenches] Whole Home UPS, Generator Charging

[Jason Szumlanski]

We are seeing an uptick in consumers looking for whole home battery backup
systems without solar panels for shorter grid outages. They either want
battery only or battery with generator charging capability, either portable
or fixed.

I was planning on offering primarily Sol-Ark 15k for this scenario. But I
have had mixed results in getting any appreciable battery charging from
generators. I had a 48kW recently barely able to provide 3kW within the
Sol-Ark's parameters, and a 22kW that can charge at 18kW without breaking a
sweat. Portable generators are all over the map, too. I've used a Honda
2200 inverter generator to charge at 1,500W, a piece of junk 8kW cage
rattler that was happy charging at 8kW, and a 5kW that didn't like giving
up even 500W.

Is there any rhyme or reason to what generators are best or why this
happens? Sometimes I'm faced with clients that have existing generators and
I have to tell them that I can't promise how well it will work. That's not
a great sales pitch.

Yes, I have adjusted the volt/freq windows and set the Sol-Ark to General
Standard. I have tried peak shaving with no real positive results for the
generators that performed poorly.

Also, if Sol-Ark isn't the best answer, I'm open to alternatives. I also
considered installing these systems with separate 48V chargers connected to
the generator output, but I'm not sure how much better that will be and if
there are adjustable chargers I can use on a range of generator outputs.

Any advice would be appreciated, and I would also like to know if others
are seeing this trend for whole home UPS. It could just be hurricane
related here, of course.

Jason Szumlanski
Florida Solar Design Group
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20241028/76c417ea/attachment.htm>