Adding wind to an existing solar + battery system

Hi,

My existing setup is 6.25kwh panels (Canadian Solar) with a 5kwh Sungrow inverter and an LG Resu 10 battery (grid connected on single phase power).

While we normally produce more than enough to cover our usage, top up the battery and send a bit to the grid each day (on a good sunny day we might produce 30-38kwh, send 20kwh to the grid and use the remaining/top up the battery).

Recently we had a week of rain/cloudy conditions where we had to buy 1-3kwh from the grid each day as we didn’t get enough sun to get the battery topped up and cover our use, which got me thinking if adding wind might be possible and economical.

Our house is elevated and a good distance from the neighbours and we a pretty constant breeze (we often don’t need to bother with the fans or AC) and I was thinking maybe we could add a small wind turbine or two into the mix.

I see Amazon Australia has a bunch of ones rated between 400wh - 800wh priced at pretty low prices (between $250-$500)

https://www.amazon.com.au/s?k=wind+turbine+generator

Has any tried adding wind into the mix? My thinking if I could get two 800wh ones on the roof, even if they only produce half their rated capacity (a total of 800wh) that would more than cover our normal household use (which as long as we aren’t running any major appliance seems to be 300-400wh/h) and keep the battery topped up when we have a week of rain and clouds.

Has anyone integrated wind into an existing system like mine and have any tips on how they did it? I’m just starting to research how to do it/if this is possible/economical but I thought i’d post here to see if anyone and point me in the right direction.

Thanks!

Hi @tlspambait

Where is your property located?

I’d be very interested to hear other people’s experience with this, although I’d also be very surprised if it was economical.

@Svarky has looked into it I think.

Cheers
Marty

Hi @tlspambait

Unfortunately, you cannot add a small (DC) wind generator to your existing system as it does not have the capability to integrate with the Sungrow & LG chem battery system. The reason is there is no way for the battery to tell the wind turbine to ramp down or turn off when it has reached full capacity. The wind turbine will just keep spinning and overload causing damage.

The only way to add a wind generator would be to use a more expensive AC wind generator which is grid-connected but it will still not be able to charge the battery directly, it will only help offset some consumption. However, the cost of setting this up will far outweigh any saving from buying 1-3kWh of
electricity from the grid.

In my experience with small scale wind turbines I have concluded that is far easier and more reliable to just add more solar (if possible). Small cheap wind turbines can be very problematic.

Thanks for the responses, its too bad this doesn’t look viable. Most of the posts of various forums were quite dated and for off grid systems so I wasn’t finding much of a starting point.

I was just hoping there might be some option at a reasonable cost to supplement solar – I hate buying power that’s likely come from coal! Hopefully the technology catches up in a few years and there might be some options!

At least the sun is back to shining today and my battery is at 100%!

I should have mentioned the more advanced off-grid inverters do have the capability of using multiple generation sources including, solar, wind, hydro, etc to charge a battery. However, your economical Sungrow hyrbid inverter does not have the capability to control multiple DC-coupled energy sources.

The more advanced off-grid systems are much more expensive but they are very flexible and modular making adding more solar or wind possible.

I can understand why you do not want to use electricity made from coal so another option is to use an electricity retailer like Momentum or Powershop who source their energy from renewable sources and support renewable projects.

Unfortunately I’m in Ergon territory, so I have no choice of retailer (or of a good feed-in tarriff!) Cheers.

I pretty much agree, and I don’t know the Sungrow system, but I don’t understand why a wind turbine cannot be used in parallel if if has its own integrated controller. That controller should sense when the batteries need no more charging and turn-off. What am I missing please?

@cjpetrie

The wind turbine controller would need to have Can-BUS (RS485) communications with the battery, but I don’t know of any wind controllers that have this. Also, this would conflict with the Can-BUS comms to the Sungrow inverter.

The only way this could work is by using an AC-coupled wind generator. Then the Sungrow energy meter (CT) can be set to use excess AC generation to charge a battery. However, this would only work with a grid-connected system.

(Note: only more advanced multi-mode inverters have current shunt inputs so they can monitor and control more than one DC coupled source)

My situation is different. I have an off-grid system with the batteries charged by a MPPT controller from the panels. The inverter is separate. So it would seem a wind turbine with its own controller could also charge the batteries. If it sees an overcharge, it should shut down. Is this not how it would work? I haven’t done this but am contemplating it for a future add-on.