DIY PV install ideas

hermitdave

hermitdave

Member
Joined
Aug 12, 2018
Messages
254
Hello folks,

I picked up 16 Siliken SLKM6L modules and SolarEdge SE3680H inverter a few days ago.

Since I have zero experience installing this, I plan to install 4 PV module on top of single storey extension. I was thinking of using micro-inverters on the 4 panels and see the output. Once I am happy, I was planning to get a scaffolding set in place to mount the remaining 10 panels on the main roof. The main roof could use the Solar Edge inverter.

My question is, can multiple grid tie inverters function together without issues ? If micro-inverters can, the answer should be obviously.

Any thoughts on the subject ?
 
I don't have any practical/meaningful experience but I believe that micro-inverters produce AC (with a sine wave) and when you combine them they have to go thru something (piece of equipment) to combine/synchronize the AC.
 
OffGridInTheCity said:
I don't have any practical/meaningful experience but I believe that micro-inverters produce AC (with a sine wave) and when you combine them they have to go thru something (piece of equipment) to combine/synchronize the AC.
Click to expand...

My understanding is that micro inverters can be stringed together but thats it theres nothing else. Micro inverter can connect to main consumer unit with 2 pole breaker and nothing else on between
 
hermitdave said:
OffGridInTheCity said:
I don't have any practical/meaningful experience but I believe that micro-inverters produce AC (with a sine wave) and when you combine them they have to go thru something (piece of equipment) to combine/synchronize the AC.
Click to expand...

My understanding is that micro inverters can be stringed together but thats it theres nothing else. Micro inverter can connect to main consumer unit with 2 pole breaker and nothing else on between
Click to expand...

Intersting. As I said, I don't know what I'm talking about :) Maybe the 'combiner' I saw was for centralized monitoring - e.g. some of these micro inverters let you get monitoring info from each one. In any case - I look forward to learning about your situation on this thread.
 
OffGridInTheCity said:
hermitdave said:
OffGridInTheCity said:
I don't have any practical/meaningful experience but I believe that micro-inverters produce AC (with a sine wave) and when you combine them they have to go thru something (piece of equipment) to combine/synchronize the AC.
Click to expand...

My understanding is that micro inverters can be stringed together but thats it theres nothing else. Micro inverter can connect to main consumer unit with 2 pole breaker and nothing else on between
Click to expand...

Intersting. As I said, I don't know what I'm talking about :) Maybe the 'combiner' I saw was for centralized monitoring - e.g. some of these micro inverters let you get monitoring info from each one. In any case - I look forward to learning about your situation on this thread.
Click to expand...

Yes they often have a gateway that allows monitoring.
 
There's two different types of micro-inverters that i've seen. One type is grid-tied. They have these in Fl all over the place. Last year when half the state was out of power, a LOT of solar owner were ticked off because they had 100's of kW's of panels, but they couldn't use them.
So these are like the one hermitdave mentions, just connects to the mains through a breaker. Essentially it's "backfeeding" through the breaker.

The other type of micro-inverter is like having a bunch of UPS units that are synced. You have 1 main unit, the one in the house, that sends out a particular sine wave, doesn't have be to 60Hz as the power goes through this unit before it goes out to the house. Then all the MI's just sync up to that output and push the voltage high enough to feed the unit. Each MI is also an MPPT as well.

Both of these systems do NOT use battery backup, unfortunately. I'm not aware of any that do. But that doesn't mean that there isn't some that do use battery backup.
 
Thank you @korishan. I was only aware of 1st type.

I wonder if I buy a small 1kW inverter, can I house it in an electrical enclosure outside? It would need weatherproofing while being ventilated
 
Just be aware of the approx 15 (10-20) % power loss in AC coupled systems "round trip" to/from storage (if any).
If you've got reasons like plenty of roof space & need/want simpler wiring, etc, then no problem.
 
Redpacket said:
Just be aware of the approx 15 (10-20) % power loss in AC coupled systems "round trip" to/from storage (if any).
If you've got reasons like plenty of roof space & need/want simpler wiring, etc, then no problem.
Click to expand...

Conversion losses I agree
PV to AC
AC to DC
DC to AC
15-20% would be about right.
I am after loosely coupled system so no way around that
 
You must log in or register to reply here.
Back
Top