Prime numbers problem

[svetz]

I Like @wattmatters' solution, make the top the same angle as the sides and it's just two strings. Alternatively, run the last set of panels with microinverters and feed them to a hybrid inverter (i.e., AC coupled)? With the low power panels, you should be able to get inexpensive microinverters.

 

[Rednecktek]

I Like @wattmatters' solution, make the top the same angle as the sides and it's just two strings. Alternatively, run the last set of panels with microinverters and feed them to a hybrid inverter (i.e., AC coupled)? With the low power panels, you should be able to get inexpensive microinverters.

That requires grid tie in and that's another $45,000 to make happen. The two strings idea might work though.

 

[Skypower]

The reason the video was linked was to show the ability of the LV6548 to run various high loads.

Right I know but that’s one inverter and it can do that, but I wouldn’t try that with multiple inverters in three phase or split phase configuration.

 

[camelCase]

For occasional welding and fabricating work, he'd be better served with buying a Lincoln or Miller gas powered multi-process welder. It would do double duty as a backup power source in a pinch, too.

 

[svetz]

[using microinverters for the oddly-placed panels] requires grid tie in [with a string inverter] and that's another $45,000 to make happen.

AC Coupling wouldn't be useful if the grid had to be up to get solar power, it just needs your main inverter (or battery like the Tesla Powerwall) to control the microinverters. I think the SolArk would work (see page 31) and @GXMnow has microinverters running into his Schneider, also linking @Ampster as I believe he has them running into a Skybox and he might have some ideas.

You can pick up M15 microinverters for those low-powered panels off eBay for under $60, so might be an inexpensive way to go.

 

[Zwy]

For occasional welding and fabricating work, he'd be better served with buying a Lincoln or Miller gas powered multi-process welder. It would do double duty as a backup power source in a pinch, too.

Ever own one? I have a Miller Bobcat 250 and it loves fuel.........

Would be money ahead to own a separate inverter style generator for backup.

 

[camelCase]

Ever own one? I have a Miller Bobcat 250 and it loves fuel.........

Would be money ahead to own a separate inverter style generator for backup.

True that. I don't own one, but have used them to glue equipment back together. (My welds look like chicken poop.) A 250 would basically have a commercial twin cylinder riding lawn mower engine.

 

[Rednecktek]

For occasional welding and fabricating work, he'd be better served with buying a Lincoln or Miller gas powered multi-process welder. It would do double duty as a backup power source in a pinch, too.

Lol! That's what he's got out there now and it requires holding it the right way, a can of starter fluid, dancing widdershins 3 times and a chicken to get the damn thing started each time.

AC Coupling wouldn't be useful if the grid had to be up to get solar power, it just needs your main inverter (or battery like the Tesla Powerwall) to control the microinverters. I think the SolArk would work (see page 31) and @GXMnow has microinverters running into his Schneider, also linking @Ampster as I believe he has them running into a Skybox and he might have some ideas.

Now see, I had a whole thread about microinverters off-grid and I was told that microinverters required the grid to function and that you can't use them off-grid.

 

[svetz]

Now see, I had a whole thread about microinverters off-grid and I was told that microinverters required the grid to function and that you can't use them off-grid.

Apologies for that, left a post to hopefully make it clearer for other readers.

BTW, in my earlier post I referenced Enphase microinverters off eBay. Decent gear, but might not be the best way to go as they're going to want an Envoy for activation most likely (not sure with the older inverters, might be a way around it).

 

[Rednecktek]

Apologies for that, left a post to hopefully make it clearer for other readers.

I just read that and it helps, thank you.

Still seems that microinverters are not really a good solution compared to just getting more panels next time he's in town.

Fortunately it's still a work-in-progress and he is probably only firing up the plasma cutter and air compressor for maybe 1 hour a week, so LOTS of time to refill the batteries. Definitely room to grow there.

Remember, we're sailors and time is a variable to us.

 

[svetz]

Still seems that microinverters are not really a good solution compared to just getting more panels next time he's in town.

Not sure what you mean, sounds like apples and oranges comparison.

Not sure what the costs would be, haven't looked in a long time (Enphase gear is good, but AP Systems is a lot cheaper and probably more so off eBay). But wanted to throw it out as an option as microinverters shine when the panels are at different orientations, have shade, or you can't plan well enough to know if you'll need more capacity.

BTW, just to be clear, the idea wasn't to use all microinverters..., it was to use a string inverter that worked with microinverters. That way you had the best of both worlds, that is the microinverters would only be used on the few panels that don't align with other panels where they would degrade string performance. It's to allow you to better use the barn roof geometry.

 

[Rednecktek]

BTW, just to be clear, the idea wasn't to use all microinverters..., it was to use a string inverter that worked with microinverters. That way you had the best of both worlds, that is the microinverters would only be used on the few panels that don't align with other panels where they would degrade string performance. It's to allow you to better use the barn roof geometry.

Aaahhh, so just on the oddball string and let the rest of the system provide the "control voltage" for that center string?

 

[svetz]

If your oddball string is all the same panel type with the same angle and w/o shade, this might be an inexpensive way to go: