Jump to content

Night losses


dpmiller

Recommended Posts

Our PV uses six Hoymiles dual microinverters. These have a dark current of around 25W each so the 150 or so Watts that they're supping overnight is a consideration. As I've a twilight switched circuit for the outside lights, any harm in using it to control a contactor, taking the inverters offline at night?

Link to comment
Share on other sites

25W each is a bit savage.  My four old-school (>10 years old) SunnyBoy string inverters (my rooftop array is in 4 parts) is drawing less than 1W per inverter at the moment.

 

In fact 2 of yours would be about our entire overnight load (mainly the fridge/freezer): are you sure that figure is right?  It might look like that with simpler (eg plain current clamp) load measuring, while actually being much lower.

 

Rgds

 

Damon

Link to comment
Share on other sites

Does look like you're correct, @DamonHD and that it might be something power factor-ish. Book says sub-50mW each but I'm kinda loathe to take as gospel Chinese specs...

 

Both of my CT-monitors, an Owl and a Sava read about the same; are there any low-cost options for more accurate monitoring that'll let me confirm what's going on?

Link to comment
Share on other sites

Sounds like the power factor is confusing the CT.

Can you look at your main meter and see if it is really drawing current at night.  150W would soon show up at 1 flash of the LED for every Wh.

 

9 hours ago, DamonHD said:

In fact 2 of yours would be about our entire overnight load (mainly the fridge/freezer)

Time for new white goods then.  My fridge uses next to nothing.

Link to comment
Share on other sites

2 minutes ago, dpmiller said:

I could certainly try,  I'd need to kill all the other loads tho as the MVHR probably uses a coouple of hundred watts.

Got to be an hour well spent.

Only a case of flipping the circuit breakers on everything except the PV.

And then spending the rest of the night resetting anything that does not auto rest.

Edited by SteamyTea
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...