240V Batteryless, Utility Backedup Inverter

[bob.longmire]

Hi,

I've seen that some inverters can run Battery free off Utility/Grid AC.

But I can't seem to find one that will do this with 240V input/output. Some of the units that can function in series/paralell say that the Grid-Backup only works for 120V.

Is there an inverter, or 2 in parallel, I can run a 50 AMP Grid AC line to, and have it use solar first, and grid as needed?

I'm trying to avoid the batteries to save cost on the whole system.

Any general guidance/advice on the best way to run an AC with solar during the day and grid at night (or when a bird lands on the panel?).

Thanks all!

 

[chrisski]

You seem to be describing grid tied solar in the US.

What keeps me away from installing what you describe is the permitting and inspection process. The grid tied inverters without batteries can take a much broader range DC input from a solar panel.

This inverter has an 80-600 VDC input range

Fronius Primo 6.0-1 6,000 Watt Grid-Tie Inverter

Note: This item is on backorder, We expect to have it back in stock sometime in August, 2022

www.solar-electric.com

Versus the battery tied 24 volt inverter I have that has an input range of 21.4 - 33 VDC.

https://samlexamerica.com/wp-content/uploads/2020/01/11001-PST-3000-12-24-1221_Lrez.pdf

That first inverter looks tied to have only panels in all sorts of parallel, series, and series parallel configurations without a battery.

 

[bob.longmire]

Yes, sorry, I should have been more clear. I'm not going to run the entire house on the Solar.

I'm only running the AC and electric car charger, so it won't be hooked into the panel and shouldn't have any backfeed onto the grid in the event of an outage.

It's like grid-tied solar for 2 outlets.

Does that help?

Thanks!

 

[chrisski]

If you're asking for 3000-watt solar inverter that will run without battery and does not need the grid, then I have not found anything like that for sale.

I have a solar inverter that runs off the battery and panels. I am able to get a 2000 watt load supplied constantly from the solar panel, but when the load turns on, there's several seconds that the batteries need to provide the energy as the solar panels catch up. Also, when a cloud goes overhead, the battery needs to supply the energy the panel can't make. I think of it as a buffer.

There are inverters that don't need batteries to be used, and these can power a load, but then you still have the problem of what happens when a cloud goes over. Will made a video of something similar:

I don't know if you can get two of those Growatt inverter and use L1 and L2 to make 240 volts as some inverters can, or if multiple inverters can be set up to in parallel provide more power.

 

[ncsolarelectric]

The Sol-Ark inverters can operate from solar without the battery if there is enough sunlight and solar panels present. However, your AC Unit needs to have a soft-start or a very low inrush current since there are no batteries to draw the surge current from when the compressor starts. The car charger should be okay, but most Level 2 chargers are around 7.5kW. You would need at least 10kW of solar to hope to provide full power to the charger, long enough to get a full charge in a couple of days. Sol-Ark makes a 12kW inverter that has 120/240V output for a sub-panel.
Until a few weeks ago, I didn't know it could do this. Now they have my attention.

 

[bob.longmire]

Yeah, I'm hoping to use the grid as the battery. So when a cloud goes over, it uses AC from the grid.

It looks like 2 of the Sol-Arc in parallel could do this. It says battery or batteryless function in 240V Sol-Arc Inverter.

i think this may be the one (if i get two)

Thanks!

 

[ncsolarelectric]

Yeah, I'm hoping to use the grid as the battery. So when a cloud goes over, it uses AC from the grid.

It looks like 2 of the Sol-Arc in parallel could do this. It says battery or batteryless function in 240V Sol-Arc Inverter.

i think this may be the one (if i get two)

Thanks!

LMK if it works, please.