Margali's Griffin Wood Ranch

Weldman

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Got any leads or ideas for low watts? My 100W solar panel is only putting out ~20 for some reason. The fencer is taking about 8W and the little fountain pump is listed as 2.5W.
Yeah but it won't put out any air further than 2' that isn't worth mentioning. Anything over 77°F a solar panel will decrease output by 0.2% or thereabouts which is part of the reason your solar panel isn't at optimal, age is another factor as they lose 1% per a year in efficiency, mono or polycrystalline panels has an effect and lastly solar panels are about only 85% efficient as is coming from the factory.
 

Margali

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@Weldman The brand new panel came with 1ft long 14AWG leads but 10AWG is the largest wire I could fit into the terminals on Victron controller. The table I found said 12V system with 100W could go 33ft on 10AWG with <5% drop.

Is it 2% per degree above 77F? At 100F that would be:
Panel Panel Eff. Temp De-Rate Wire De-Rate
100W * 0.85 * 0.954 * 0.95 = 77W

That is still triple what I'm getting. I need to find an electricity for dummies course...
 

Ridgetop

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Back to misters - look in rabbit supply catalogs for misters. KW has been around for a long time. There are different types - some screw into nipples that attach to 1/2" PVC. Others are inserted into poly tubing. Yi can connect them to a garden hose. The newer ones put out so little water that the ground will not get sloppy, maybe barely damp. Also look in Lowes in the garden irrigation line department - sometimes they have them there. Misters can lower the ambient temperature in the barn by as much as 10-20%.

If the water pressure is too great, the rabbit catalogs also sell pressure reducers that will reduce the water pressure for drinking lines. We have a farm main on our property here in CA. In spite of having to travel over 500' straight uphill to our property we had to put on a reducer in the barn.

There are even battery regulators that you can connect to the misters that will automatically turn them on when the temperatures reach a certain point.

I put them all around my barn here in CA when DH was raising his rabbits. During a hot spell in February (we have occasional 100+ degree flash heat spells in winter) we lost several litters so I put up misters and we never lost another rabbit from heat. My kids were little at the time (about the ages of yours) and they helped. Putting the misters up was super simple and only took a couple hours. With no power in the barn misters are your best solution for now.
 

Weldman

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@Weldman The brand new panel came with 1ft long 14AWG leads but 10AWG is the largest wire I could fit into the terminals on Victron controller. The table I found said 12V system with 100W could go 33ft on 10AWG with <5% drop.

Is it 2% per degree above 77F? At 100F that would be:
Panel Panel Eff. Temp De-Rate Wire De-Rate
100W * 0.85 * 0.954 * 0.95 = 77W

That is still triple what I'm getting. I need to find an electricity for dummies course...
Missing amps/voltage here in this equation for me to answer this , not the nominal voltage of 12V. Yes you are supposed to be at least getting 70W, what brand of panel you have, direction it is orientated and the angle it's sitting at?
It's not the watts determining the length of the wiring, it's the voltage.
Though I think the .954 is off cause that's only 4.77° and Texas in the summer time is way over 81.77°F, either way something isn't right. Is this going to a battery?
Well that post even screws me up! 😱
Wow...I'm plug & play oriented. 🤣
Pretty simple, she has a 100W panel with the efficiency of 85% which is 0.85 take that number and set it to aside, take the temperature de rate for how hot it is over 77°F which is 4.77° which is 0.2% per each degree over 77°F which means she has 0.954% drop so take that 0.954 and multiply it by the panel efficiency of 0.85% take that answer and times it by the 5% power loss from wiring equals 77W.
 

Margali

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@Weldman Yes, going to biggest 12V battery I could carry at Walmart. Solar panel is mounted in full sun at ~30 degree angle with long axis oriented roughly West - East. Hyper links to items:

Victron SmartSolar MPPT 75V, 15 amp, 12V or 24V

Renogy Solar Panel 100 Watt 12 Volt

10 AWG 2 Conductor Copper Cable 26FT 300V


Did you mean 2.0 %/F vs 0.2 %/F
temperature de rate for how hot it is over 77°F ------- which is 0.2% per each degree over 77°F
(100F - 77F) = 23 F * 2.0 %/F = 46% loss = 1- 0.46 = 0.55 efficient
that would give
100W * 0.85 * 0.55 * 0.95 = 44.4W
 

Weldman

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...pours stiff drink.... 30 minutes later....
Alright lets just erase the chalkboard here, I'm sure you are getting the 20W from a Bluetooth app on your phone of what the Victron is saying, yet about . So just as my system says I only got 4 to 5k going in from half of my 12.1kW system I'm sure there is more to come in, but the CC (charge controller) doesn't need it so it dials back. There is 3 phases to charging a battery bulk, absorb, and float. Bulk is when it's shoving in much as possible, absorb dials back the voltage/amperage to let it absorb, the deeper the discharge the longer you want your absorption rate, then you got float, the last 10% to fill a battery up or less which only few volts above a charged battery would be.
Forth stage is equalization/desulphation you want to do monthly to keep sulphating from building up on plates.

Speaking of which a full 12V battery is 12.7VDC and multiply that by each 12V you go up in system sizes. If your battery ever shows 12VDC it's about 50 to 40% full which you don't want, you want to keep around 80% SOC (state of charge)
Car batteries last a year or two, deep cycle batteries about 3 years, golf cart batteries about 3 to 5 years if you get the 6VDC ones, the 2VDC batteries can get about 10 plus years all due to thickness of the plates, the thicker the plates the longer it takes to charge them too.
I'm sure the battery didn't say how many Ah either only CCA (cold cranking amps), most batteries in the solar world are Ah rated (amp hours) based on 20 hr rate and 6 hr rate on forklift batteries. One hundred Ah battery would discharge to 0 at 5 Ah which you don't want to do so that 100 Ah battery is actually only good for 50Ah at most. With only 20% DOD (depth of discharge) which is optimum you only for 20 Ah and just as the solar panels that varies on temperatures.
You never mentioned the inverter size either, the larger the inverter the more draw it has when on, on idle.
Keep inverter size matched to solar panel size, about 1.35 over solar panel wattage is max you want. My system of 12.1kW would want the max inverter size of 16.336kW
This is the basics of FLA (flooded lead acid batteries)
Basically plug in a fan and relax if the inverter is large enough to handle it.

Be nice to know what battery you have too to know what is required to keep it up.
 

farmerjan

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...pours stiff drink.... 30 minutes later....
Alright lets just erase the chalkboard here, I'm sure you are getting the 20W from a Bluetooth app on your phone of what the Victron is saying, yet about . So just as my system says I only got 4 to 5k going in from half of my 12.1kW system I'm sure there is more to come in, but the CC (charge controller) doesn't need it so it dials back. There is 3 phases to charging a battery bulk, absorb, and float. Bulk is when it's shoving in much as possible, absorb dials back the voltage/amperage to let it absorb, the deeper the discharge the longer you want your absorption rate, then you got float, the last 10% to fill a battery up or less which only few volts above a charged battery would be.
Forth stage is equalization/desulphation you want to do monthly to keep sulphating from building up on plates.

Speaking of which a full 12V battery is 12.7VDC and multiply that by each 12V you go up in system sizes. If your battery ever shows 12VDC it's about 50 to 40% full which you don't want, you want to keep around 80% SOC (state of charge)
Car batteries last a year or two, deep cycle batteries about 3 years, golf cart batteries about 3 to 5 years if you get the 6VDC ones, the 2VDC batteries can get about 10 plus years all due to thickness of the plates, the thicker the plates the longer it takes to charge them too.
I'm sure the battery didn't say how many Ah either only CCA (cold cranking amps), most batteries in the solar world are Ah rated (amp hours) based on 20 hr rate and 6 hr rate on forklift batteries. One hundred Ah battery would discharge to 0 at 5 Ah which you don't want to do so that 100 Ah battery is actually only good for 50Ah at most. With only 20% DOD (depth of discharge) which is optimum you only for 20 Ah and just as the solar panels that varies on temperatures.
You never mentioned the inverter size either, the larger the inverter the more draw it has when on, on idle.
Keep inverter size matched to solar panel size, about 1.35 over solar panel wattage is max you want. My system of 12.1kW would want the max inverter size of 16.336kW
This is the basics of FLA (flooded lead acid batteries)
Basically plug in a fan and relax if the inverter is large enough to handle it.

Be nice to know what battery you have too to know what is required to keep it up.
:idunno:idunno:idunno😵‍💫😵‍💫😵‍💫:th:th


:lol::lol::lol:
 

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