Greenhouse Power Supply Upgrade

[Boofer]

I'm upgrading the power supply for my greenhouse and I wanted to elicit opinions on it before I wired it up. The original layout included four 100 watt panels, one MPPT, one inverter, and four 138ah LiFePO4 batteries. I'm adding four more batteries, a second MPPT, two 200 watt panels, two 100 watt panels, and a turbine. The turbine has an onboard MPPT.

 

[Boofer]

Okay, so I'm working in a vacuum...no opinions available, I guess.

Just hoping for a sanity check. Did my attempt to sketch it cause confusion?

 

[chrisski]

Do you have a Kwh per day requirement? number of days reserve for cloudy rather?

 

[Boofer]

Do you have a Kwh per day requirement? number of days reserve for cloudy rather?

Thanks for responding. I just want to power some LED grow lights and seed heating mats. The first iteration of this power supply was brought online late 2019. Then I saw how a week or longer of Pacific Northwest fall and winter can impact greenhouse growing. So I've doubled battery storage and boosted the supplied solar power.

I figure 3012wh x 3 (cloudy days) = 9036wh total
9036wh / 8 (hours of sun) = 1129.5w needed

I'm pushing it and being optimistic...the solar array hopefully will deliver something close to 1000w. Perhaps with a little help from the wind turbine, I may be closer to the 1129.5w target.

 

[chrisski]

You have a lot of shunts, so you should know if 1000 watts of PV will be enough, but I think you may need a lot more to build 9 kWh of power in a single day to last you three cloudy days.

Here is a good posting from another forum on panels and battery requirements based off Seattle and TUscon.

Solar Off-Grid Battery Design - Solar Panels - Solar Panels Forum

Discuss remote solar applications for homes, cabins, RV and boats. If you have a question on equipment for an off grid system, such as charge controllers or inverters, then post your question in this forum.

www.solarpaneltalk.com

I’m basically located in TUscon which is best case getting 5.6 sun hours per day, and you’re in the Pacific Northwest getting 1.2 sun hours per day. Those are the worst days of the year in winter. Sun hours will come over a website like PV watts.

If that number is correct, and you want to produce 9kwh per day to last you three days, math in my head says you need about 8 kWh of panels to make this in a winter day. I doubt you are running the greenhouse in winter times, so whatever the sun hours per day is off of PV watts. That website in the sun hours per day includes local weather patterns along with hours from sunset to sunrise and height of the sun.

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Aside from that, I don’t know a lot about wind power, but a 20 amp fuse for a 12 volt system does not seem like it will be enough for those super windy days. If the onboard MPPT limits production to 15 amps or less that’ll be fine. Which windmill did you get? I was looking at an Air Primus for a project, but did not get it. It came with everything including dump loads and excessive wind braking.

As far as I can tell, the only way to know wind mill production is to set it up and hope for the best.

 

[Boofer]

You have a lot of shunts,

Is that a problem?

Which windmill did you get?

Tycon Systems TPW-400DT-12--24 Horizontal Wind Turbine: Tycon Systems turbine

Thank you for the website link and directing me to "Solar Power Your Home for Dummies". Guess I'm a little "pie in the sky" with my expectations. Need to identify lower wattage grow lights, etc.

 

[chrisski]

I think that many shunts is good. It lets you know know exactly w hat you’re using at each point of the systeM. If you’re upgrading the system, and you have the shunts now, this gives you a good idea if the panels you’re buying will give you the power you need.

For the windmill, the chart on AMazon up top says a max output of 13 amps, but on bottom in the questions, the max output question says 26.4 amps. If that’s true, a 20 amp fuse may be a little small.

 

[Boofer]

I think that many shunts is good. It lets you know know exactly w hat you’re using at each point of the systeM. If you’re upgrading the system, and you have the shunts now, this gives you a good idea if the panels you’re buying will give you the power you need.

For the windmill, the chart on AMazon up top says a max output of 13 amps, but on bottom in the questions, the max output question says 26.4 amps. If that’s true, a 20 amp fuse may be a little small.

Yeah, I think the seller Remote Power Source is wrong. That chart from the vendor Tycon Systems shows around 14 amps max.

I see that I need a disconnect for the turbine, but do you see any other glaring errors or problems?

 

[chrisski]

Each of the MPPT gets 2s2p for panels. The 100 watt panels in the left looks fine. The other one will be good if VOC for the two 100 watt panels matches the VOC for the two 200 watt panels.
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Also, I think your amp calculation is wrong since they’re 2s2p. I think you should be dividing by 34.
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don’t see a need for a fuse and breaker by the battery. I think you want a class c fuse for lithium.
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Your SCC and Inverter probably has a chassis ground.
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Not sure of the reason for the second solar disconnect on the 600 watt panels. I think that needs to go to the windmill.
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I’d want a fuse on the dc fuse block. For my fuse block I added, I went with a 50 amp Maxi fuse

 

[Boofer]

I clarified the solar disconnects and grounding. The turbine booklet states 20 amp fuse should be used. All power inputs should have disconnects. Can you clarify VOC concerns? What's a "class c fuse for lithium"? Why does the dc fuse block need a fuse? Each connection on there is already individually fused.

My initial wiring design came from Will Prowse. That's why I had a 175 amp fuse right off the battery bank and a 175 amp breaker in front of the inverter. Is that wrong?