Grid-tied solar

[Carl_NH]

Too much information ?

I tend to do that.......

No - you explain things well and clear - much appreciated since when you see kits on line for x KW they don't really go into the electrical aspects and wire size and details needed.

Thanks again,

Carl

 

[TnAndy]

Enphase is kinda nice in that you can see how many systems are around the world (for those that have chosen to allow a limited, public view of their data....most do...it actually defaults to that unless you opt out), and get details on specific ones (the public side)....190,000 systems around the world. You can zero in on your area and see if any of your neighbors have an Enphase system.

https://enlighten.enphaseenergy.com/public_systems


For that one above I finished up last month, today is his one month online day.....his system has produced 1239kwhrs for the month it has been in operation. You can mouse over the blue boxes and see the daily production. Today, for example, was fairly lousy because we had only a little sun this morning, and rain most of the afternoon. He only did 12.3kwhrs today. On a good day, he will do mid-60's.

Click on "Energy Production"....it has Months, Days, Hours. If you use the hours section, you can about tell the sunshine quality of any give day.

https://enlighten.enphaseenergy.com/pv/public_systems/sntr451420/grid/months

 

[Redneck in training]

Enphase is great for DYI installation. Certain disadvantage is that it can't be islanded or used to charge batteries while off grid. If you can install a breaker and/or new outlet you should be able to install PV system with microinverters.

 

[farmer2009]

Good info. Nice web site to track generation.

 

[TnAndy]

Enphase is great for DYI installation. Certain disadvantage is that it can't be islanded or used to charge batteries while off grid. If you can install a breaker and/or new outlet you should be able to install PV system with microinverters.

Yep....that is true. They are designed for grid tie ONLY situations. No grid power, they shut off. Folks considering a system need to get that important point.

But on the plus side, the install is so much more simple, and far cheaper.....batteries ain't cheap. One needs to decide WHY you want a system.....backup power, OR strictly reduction of electric bill......then pick which road to travel. My guess is 90%+ of grid tied systems do not include backup power. And that's OK, as long as you understand the difference.

My own system, I started with a grid tied, battery backup system using a pair of Outback 2500w inverters. (master/slave arrangement gives true 240AC output) I have 6kw of panels on that system, which maxes out the 5,000w output of the inverters. If grid power goes down, I flip a transfer switch, and we keep on operating off that amount of power. It's enough to take care of the basics...refrigeration, lights, and a few other uses I consider important.

Then I added 5kw of Enphase based panels/inverters that grid tie only.

Between the two, we have no electric bill, and generate about a 50-60 buck/mo credit. They will issue us a check at the end of the year if the amount is positive. Right now, we're up about 500 bucks.

Redneck IT:

Visited your Enphase site....WOW....that's a heck of a system ! 96 inverters = about what, 24kw system ? That's a honking BIG system.

 

[ultrarunner]

Anyone have this inverter which is grid tied AND provides a single outlet without batteries?

Seems like a practical solutions... enough to keep data or maybe a refrigerator working?

SMA 5000TL-US Sunny Boy Grid Tie Inverter with Emergency Power Outlet

 

[buickanddeere]

Anyone have this inverter which is grid tied AND provides a single outlet without batteries?

Seems like a practical solutions... enough to keep data or maybe a refrigerator working?

SMA 5000TL-US Sunny Boy Grid Tie Inverter with Emergency Power Outlet

How does that operate a few priority loads when the utility grid goes down and there are no batteries ?

 

[Scooby074]

How does that operate a few priority loads when the utility grid goes down and there are no batteries ?

It will only generate AC from whatever DC is present. Ie: if the outage is at night you are SOL. I dont believe there is a way to add a battery pack to the unit to provide some overnight power. I suppose you could use the "emergency" power to charge up a UPS or something similar.

"he Sunny Boy 5000TL-US ships with a handful of new features including an SMA exclusive Secure Power Supply (SPS) which can provide up to 1,500 watts of dedicated power in the event of a daytime power outage"

 

[buickanddeere]

A battery buffer is required. You can't operate a typical AC load with just solar panels and an inverter with nothing in between. If the inverter is grid tie it's not going to output power with the utility down.

 

[TnAndy]

A battery buffer is required. You can't operate a typical AC load with just solar panels and an inverter with nothing in between. If the inverter is grid tie it's not going to output power with the utility down.

Near as I can read, there is no battery in the unit. (no actual experience with these)

My guess is they use some capacitors as a very small buffer, but when the power from the panels falls to a certain point, it simply shuts down the limited off grid outlet.

Or it may simply be a case of full 1500watts ( if you have enough sun on the panels), or nothing (if it falls to 1499w)...I wouldn't think so, since that would play havoc with some electrical things....one one second, off the next if a cloud passed over, on again shortly later. ( Which IS one reason you typically want batteries in an off grid system....a GOOD buffer)