Hunting cabin with air conditioning, it's florida for God's sake

[wetsu151]

We don't roll like that , will be getting a new Kubota/Mecc alt genset , smallest they have and I feel comfortable with is 7kw unit, we had a 9.5kw
Also will be sizing this Solar setup to run a small deep freezer and led lighting

[Mike90250]

....The smallest they make is a 7kva genset, sips .25 gph at 50% load. Thank goodness we have a few of us chipping in for the cost

Check papers and fleabay for Lister or Changfa diesels, may be able to find a genset, or cobble one together yourself

http://www.microcogen.info/index.php?topic=3557.0

[wetsu151]

Thanks, no insurance , as its probably cost prohibitive due to the remote location, but never checked. No Physical injuries, just mental.
The a/c's pull 800 watts each, the freezer is manual defrost and is 100watts when running, everything else is how you described, diesel of course.
The smallest they make is a 7kva genset, sips .25 gph at 50% load. Thank goodness we have a few of us chipping in for the cost

[Sunking]

New Twist on our solar install, The wildfires in the big cypress burned down our 9.5kw Kubota generator and lawnmower. Thankfully they caught it before our cabin caught fire but we still suffered a 10K loss.
I am now trying to re-size the new generator we will buy, thinking we should get a 7kw as the most we run is two 8000btu window units, deep freezer and a 1/4hp water pump

I am going to assume those two AC units are window shakers with the lowest SEER allowed of 10 which means they use 800 watts each for a total of 1600 watts. Fridge will not use more than 500 watts during defrost cycle, 300 watts for a water pump, and another 1000 watts for toys and gizmos. 3400 watts max. 5 Kva genny is more than enough and consumes less fuel. Just make sure it is LPG, NG, or diesel. Do not use gasoline.

[J.P.M.]

New Twist on our solar install, The wildfires in the big cypress burned down our 9.5kw Kubota generator and lawnmower. Thankfully they caught it before our cabin caught fire but we still suffered a 10K loss.
I am now trying to re-size the new generator we will buy, thinking we should get a 7kw as the most we run is two 8000btu window units, deep freezer and a 1/4hp water pump

Sorry for your loss. Hope all's well and insurance covers at least some of the loss. Any injuries ?

Not being intentionally dour, but if the fire had taken the cabin, you might have had an opportunity to rebuild a structure that wasn't as much of a heat sieve as what you apparently have now.

Finding ways and means of not using energy is almost always cheaper than getting more of it. Just sayin'.

[wetsu151]

New Twist on our solar install, The wildfires in the big cypress burned down our 9.5kw Kubota generator and lawnmower. Thankfully they caught it before our cabin caught fire but we still suffered a 10K loss.
I am now trying to re-size the new generator we will buy, thinking we should get a 7kw as the most we run is two 8000btu window units, deep freezer and a 1/4hp water pump

[Sunking]

one other question, is it hard on the fla batteries to have them float charging for a couple weeks in between uses

Not at all, exact opposite is true. Float charging is the kindest gentlest charging algorithm that can be used. The reason solar users or anyone else who uses the battery daily do not use Float charging algorithm is because it takes up to 24 hours to recharge. So as obvious there is not time to recharge using Float Charge.

It is so good that is exactly what Telecom. military, and data centers use. In fact many FLA cells are Float Charged for 30 years and still going strong and capacity test confirm. However they use their batteries in a completely different application called Emergency Standby Float Service. Rectifiers hold the batteries at 54 volts on a 48 volt plant, and the rectifiers supply power to the loads. When and if there is an interruption in service, the batteries are already online and supply the power until commercial power is restored. After power is restored the batteries are Float Charged back to 100% SOC.

Another application everyone has sen, but unaware of is Emergency Egress Lighting, and Fire Alarm Control panels in every commercial building and commercial passenger airplanes. They work just like the telecom above, rectifiers (charger) Floats the batteries and supplies power under normal operation. If power fails the batteries are already online.

What makes it so kind and gentle is the Float Voltage is well below Gassing Voltage, and keeps the batteries at 100% SOC so no sulfate can build up. Where as 3-Stage charging requires an over charge voltage to speed the process up which is above Gassing Voltage. It stresses the batteries doing that. But with daily cycle applications you have no choice.

[Mike90250]

..., is it hard on the fla batteries to have them float charging for a couple weeks in between uses

not nearly as hard as letting them decline and sulfate ! A float charge for just 1 day a week, is fine to maintain a idle battery.

[wetsu151]

You guys are the Bomb, thanks for taking the time helping me figure this out

I read the manual and sure enough it says panel voltage should be 12-24 volts above battery volts for the best efficiency

I'm very exited to get this done, been wanting to a accomplish this for years

one other question, is it hard on the fla batteries to have them float charging for a couple weeks in between uses

dave

[Mike90250]

68V is going to have a hard time doing a proper EQ in the winter (when you need it most) 75v (2 in series) should be fine,

[Sunking]

Can't edit last post, continued here
at that temp extreme it comes out overvoltage, plus , if I wire them 2 in series the Vmp is 75.2
that looks to be closer to the most efficient input voltage for the flexmax 60
thanks
dave

You got it.

[wetsu151]

Thank you for the owners manual, I did not have that. Looking forward to reading that
I will have a 48v battery bank consisting of 8 batteries of the correct ah in series.
I read the info from their 2 page specification brochure dated 04/2017E
it stated peak efficiency was 68vdc input w/48v battery. (98.3%)
I read on page 102 of the owners manual that I'm probably over thinking this as the efficiency only drops to 95% even when 100v is charging a 24v bank.
I'm slightly concerned stringing my 3 panels (72 cell 325w) in series for a max Bmp of 112.8, Voc of 138. I dont think it will get cold enough here to push em over 150v. Maybe you experts can help decide
thanks as usual
dave

[ButchDeal]

Thanks mike, the specs on the outback fm-60 state peak efficiency of 98.1% is at 68vdc input, the only drawback is a few more wire lenghts

Do you have a 24V or 48V battery bank? I think you miss read the manual check page 102 again:

http://www.outbackpower.com/downloads/documents/charge_controllers/flexmax_6080/owner_manual.pdf

[Mike90250]

Thanks mike, the specs on the outback fm-60 state peak efficiency of 98.1% is at 68vdc input, the only drawback is a few more wire lenghts

At what battery voltage ? There should be charts for 12, 24, 48 battery voltages.

[wetsu151]

Thanks mike, the specs on the outback fm-60 state peak efficiency of 98.1% is at 68vdc input, the only drawback is a few more wire lenghts