I chose to not use bifacial even though we had a good setup for them. The snow shed off our barn roof would be behind them in the winter and I would use limestone screenings on the ground underneath them, which are concrete colored. So the reflection would be pretty good all year. The sales rep didn't actually try to talk me out of them but said he thought at this point in their evolution I'd be better off buying an extra mono facial panel if I needed more capacity. It's not clear how to calculate how much the increased production would be with bifacial and they have a higher up front cost, so it's harder to figure out if they're worth it. So in the end I decided to go with mono facial. I think in a few years there might be enough real world data available to do a better analysis. If I ever expand my system I'll look at them again.
I forgot about that benefit. With the 10 panel set up I was going to need to run two cables to the inverter, but with the 6 panel set up I only needed one cable. In my case I'm talking about an inverter with a really low Voc limit and a small sweet spot of operational voltage so panel choice really makes a big difference. Much less of an issue with a Fronius.
Yes.
www.fronius.com
Wow, had no idea such a thing existed. I have a Fronius Primo, so I could do this. We have a 10 year old whole house generator with an ATS, I think if it failed I would seriously look at this kind of solution. My only issue is that if the grid goes down in the winter, we use a fair bit of power to heat the water for livestock and the highest demand is at night when it's coldest. I guess if the batteries can't carry the heaters long enough the fallback would be a portable generator and plug the heaters into the generator.Yes.
e.g.:
MicroGrid & backup systems for grid independence
MicroGrids are a sustainable, inexpensive solution for ensuring a reliable source of energy in regions with an unstable power supply.
Do you have a preferred string calculator online to use? The last time I did calculations I did them by hand. I don't mind that, but it does take a bit of time.
Mine claims 3000 hour, 25 year lifespan. It will never see max hours, it will become unserviceable because parts are so expensive. They had to replace the system board under warranty, that was $800 for the part, not counting labor. Now that it's out of warranty and 10 years old, I would never put $1000 into repairs.
Yes that might be reasonable first step.
Yes, battery is the big issue. Livestock heaters are 3kW, they run about 50% duty cycle on "typical" winter day but on a cold windy night can run 100%, which means I would need 35-40kWh of battery to make it through one night which isn't cheap or compact. And it's cold enough here that batteries need to at least be in a garage or equipment room that's above freezing.
I went to their web page, it says it does as long as firmware is above certain level.
I used the Fronius tool.
