Is this setup acceptible?

[jawarren77]

My father-in-law installed this system on their lake cabin about 7-8 years ago. He as since passed away and I am looking to make sure this system is running at peak performance and if not, what needs to be improved.

System is set up as follows:
(4) Keyocera 130w TM panels in series, Outback MX-60 mppt, Magna Sine and (2) L16 6v AGM batteries. (photo shows old L16s)

Took readings off of the Outback last weekend and wondering if they are whats expected from this system.

PV Volts=65, 1.4Amps
Watts= 80
AmpHr= 34
Battery Volts= 12.5, 6.4Amps

Thanks for you input.

[sensij]

Not looking too good. 2 x L16 AGM means you've probably got something like 375-400 Ah at 12 V. Recommended charge current for AGM's is usually C/5, 75-80 A in your case. You wrote 6.4 A... was that in the middle of the eclipse?

Without knowing your loads and usage it is hard to set expectations. Are you using it just a few days in the summer? The requirements will be different than if you intend to live there full time year round.

[jawarren77]

Its only used mainly during the summer. It was overcast when I took the readings. We winterize in October and open up in April.
All lights in the house are LED and when we need to use the Well pump or Microwave we turn the generator on (which we can charge the batteries with as well).
We also have a propane fridge that requires constant 12v source for ignition.
The L16s are http://www.fullriverbattery.com/prod...teries/DC400-6

[jawarren77]

After running some quick calcs, looks like we have about 3310 watt hours/day (very high fluff factor) our biggest draw is our 12v LP fridge @1600 watt hours/day.

So 100 Kwh/month.
get about 1000 W of panels and 2 more L16s to run at 24v

I also need to figure out the correct placement of the panels.

[SunEagle]

After running some quick calcs, looks like we have about 3310 watt hours/day (very high fluff factor) our biggest draw is our 12v LP fridge @1600 watt hours/day.

So 100 Kwh/month.
get about 1000 W of panels and 2 more L16s to run at 24v

I also need to figure out the correct placement of the panels.

Your current battery system is 12v @ 415Ah which can safely deliver about 1250watt hours a day. Your 4 x 130w panels with that Outback MPPT CC should be able to produce about 43 amps which is just fine for your battery system.

The problem I see is your estimated 3310 daily watt hour usage which IMO is a little high for your current set up. Going up to a 1000watt panel system and a 24v 415Ah battery system will help a lot getting you to your estimated daily watt hour usage but be careful since you will only be able to safely generate about 2500 watt hours a day if you get a lot of clouds.

[jawarren77]

In my calcs I put everything in that we plug in. We keep most things unplugged until we use them, including the Microwave (which we run the generator for usually), we only vacuum when leaving the cabin, never watch TV, but I put it in the calcs anyway, and we never have all the lights on but they are all in my calcs as well.

[sensij]

Your 4 x 130w panels with that Outback MPPT CC should be able to produce about 43 amps which is just fine for your battery system.

Recommended charge current for AGM batteries is higher than FLA (C/5 vs C/10) , so I'd say there is room to add more PV before battery capacity needs to increase.

The usage calculations look off to me.. how does a 12 V, LP fridge use 1.6 kWh daily? A typical residential refrigerator you would buy at a big box store only uses around 1 kWh daily.

[jawarren77]

Maybe I did the calc wrong. Here is the fridge: http://www.thetford.com/product/1210-ultraline/ it is the LP version.

[SunEagle]

Recommended charge current for AGM batteries is higher than FLA (C/5 vs C/10) , so I'd say there is room to add more PV before battery capacity needs to increase.

The usage calculations look off to me.. how does a 12 V, LP fridge use 1.6 kWh daily? A typical residential refrigerator you would buy at a big box store only uses around 1 kWh daily.

Yes he should go with a faster charge rate for those AGM's but the system has been around for a few years which indicates the C/10 seems to have worked but those L16's are probably close to the end of life even if they were not discharged much.

[jawarren77]

Yes he should go with a faster charge rate for those AGM's but the system has been around for a few years which indicates the C/10 seems to have worked but those L16's are probably close to the end of life even if they were not discharged much.

The L16s are 2 years old.

[SunEagle]

The L16s are 2 years old.

Ok. They should still have a lot of life in them if they have been properly equalized every once and a while.

I think your best move is to increase the panel wattage up to max out that 60A CC. That will get you closer to getting a charging rate around C/7 for that 415Ah system.

Unfortunately to get a C/5 charge rate for a 415Ah system you would need to get an 80Amp MPPT CC. At 24volts that will require almost 2000 watts so I would say if you need to increase your system you will end up spending a bit for panels, CC and batteries.

Based on some other estimates a solar/battery system can cost between $2500 & $3000 per kWh so if you were starting from scratch you could be looking at spending almost $9k for a 3kWh a day system.

[sensij]

Ok. They should still have a lot of life in them if they have been properly equalized every once and a while.

Hold on there... most AGM batteries should not be equalized. Fullriver, in their charging instructions, does not recommend equalization, and suggests only that a full "refresh charge" be completed at some interval based on storage temperature.

[sensij]

Maybe I did the calc wrong. Here is the fridge: http://www.thetford.com/product/1210-ultraline/ it is the LP version.

Are you primarily operating it with LP? I think the current draw listed only applies when running off 12 V, when propane isn't available.

[ButchDeal]

Are you primarily operating it with LP? I think the current draw listed only applies when running off 12 V, when propane isn't available.

It is a three way fridge and can operate off of 12V DC, 120V AC, or LP

Most of these are pretty inefficient in 12V mode, and yes in LP mode it should have very little if any electric load (maybe just the light).

[SunEagle]

Hold on there... most AGM batteries should not be equalized. Fullriver, in their charging instructions, does not recommend equalization, and suggests only that a full "refresh charge" be completed at some interval based on storage temperature.

Sorry. I meant a full "refresh" charge and got caught up in using the wrong term "equalize". Whenever it is called the OP needs to follow the charging procedures associated with those batteries.