First timer going full-bore in Central America

[miahallen]

Update - thanks again for all the help guys. I ordered & received my system and will post build updates in a separate thread.
I ended up with the following bits:

• (x20) Topoint JTM230-60P, 60 cell, poly, 230W
• Midnight Solar, Combiner box, 120A for 6 PV Breakers
• (x4) Midnight Solar, Circuit Breaker, DIN mount, 15A, 150VDC
• Outback, FLEXpowerONE, FX3048T, 3000W, 60Hz, 120VAC Bypass, 48VDC, GFDI, Mate3, HUB10, RTS, FM80, FN-DC, SP
• (x8)Trojan L16P 6VDC, 420AH
• Honda EU2000i with tri-fuel conversion (will be propane powered).
• all required wiring

The parts are now in a shipment to my future home, and the build will commence immediately upon arrival later next month.

[barbant]

We bought the EU3000 with the tri-fuel kit so it could run on propane. We used ours much more than you ever would, but the valves needed servicing before they should've, according to the mechanic - because not designed for propane. Also, you probably don't need auto-start, but this would be a trick considering it needs to be choked or primed.
Otherwise a great generator.
How's things going for you so far?

[paulcheung]

I use 4 panels in a series, the total VOC volts is just under the 150 volt limit, I don't too worry about it as where I live don't have cold weather, may be you should wire them 3 panels in a series to be safe, so use 15 panels wire 3 in series. and keep couple of them in case you have to replace a panel or two.

Cheers.

[miahallen]

Thanks Mike, that's great info on the generators...

Paul, these are the panels...chosen simply for cost. I could probably squeeze in 16, or 12 would be simple.

Mod note - No links to sales sites.

[paulcheung]

To OP, 14 panels is bad idea. Unless you get one of the 600volt charge controller to wire all series, if you wire 2 set of 7 series, most controllers can't manage the input voltage, not even the classic 250. I would use either 12 or 15 or 16 panels depend on the panels specs.

cheers.

[Mike90250]

You want to have a totally separate backup charging system, and flexible. I have a small gas generator that can power my IOTA charger (bad power factor and all). I have 2 smallish (3.5Kw) diesel generators as my prime & backup. The integral charger in the Inverter, only works if the inverter is working. I experience 2 week long sunless periods in winter, all run from bio-diesel.

The new style inverter generators are very fuel efficient under partial loads, but about the same when fully loaded as other generators.

You can get 48-60V DC generators, but they are quite expensive. The inverter generators only have a small 12V DC, 3 amp tap for a starter battery, and their conversion losses are quite low, internally they are 3-6 phase AC, rectified to hi-volt DC, then inverted to pure sine.

Tri-fuel EU2000's are fine, as long as you check that the conversion kit is actually working before you ship it out. LP gas is less expensive, because it has less "energy content" than gasoline, and you will burn 20-30% more of it, to create the same power. But it does store forever!

[miahallen]

Cool....thanks for the link, I just found this diagram which really helps me a lot

FLEXpowerONE.JPG

[ButchDeal]

Hey guys, thanks again for all your input and suggestions thus far. I've decided to source all my stuff from gogreensolar.com. Having said that, it seems my only real option for a decent inverter/charge is the Outback Power FX3048T. Based on these new limitations, I'm reconfiguring my proposed system as follows:

1. Shooting for 5Kwh per day or less.
2. Fudge factor - 5Kwh x 1.5 = 7.5Kwh
3. Solar isolation in December = 4Kwh/m2/day
4. Solar panel array = 7.5Kwh / 4h = 1875W required ... I would use fourteen 230W panels = 3220W
5. Battery size required = 5Kwh x 5 = 25Kwh / 48V = approx 520Ah @ 48V
6. Charge controller = 3220wh / 48V = 67A ... I would use a 150A MidNite Solar Classic 150
7. Battery bank = 8 x Rolls S-530 530Ah 6V = 530Ah @ 48V

Does it seem my system will is adequate to the tasks?

The other question is about the charge controller, it seems the Outback Power FX3048T has one built in, do I really need the separate charge controller? Why?

You need a charge controller as that is the equipment that the PV panels are connected to. to put it simply, the CC controlls the panels output and feeds it to the DC BUS (batteries). The Outback inverters does have a battery charge capability but that is from AC power to the DC bus not from DC Panels to DC battery.
You might want to look at an integrated system like the flexpower One which has all this integrated designed together :

http://www.outbackpower.com/outback-products/integrated-systems/item/flexpower-one?category_id=441

[miahallen]

Hey guys, thanks again for all your input and suggestions thus far. I've decided to source all my stuff from gogreensolar.com. Having said that, it seems my only real option for a decent inverter/charge is the Outback Power FX3048T. Based on these new limitations, I'm reconfiguring my proposed system as follows:

1. Shooting for 5Kwh per day or less.
2. Fudge factor - 5Kwh x 1.5 = 7.5Kwh
3. Solar isolation in December = 4Kwh/m2/day
4. Solar panel array = 7.5Kwh / 4h = 1875W required ... I would use fourteen 230W panels = 3220W
5. Battery size required = 5Kwh x 5 = 25Kwh / 48V = approx 520Ah @ 48V
6. Charge controller = 3220wh / 48V = 67A ... I would use a 150A MidNite Solar Classic 150
7. Battery bank = 8 x Rolls S-530 530Ah 6V = 530Ah @ 48V

I'm using 14 panels just simply because the roof I'm mounting them on is the perfect dimensions to mount 14 evenly. I'll buy a pallet of 20 and sell the extras to my off-grid neighbors.
I don't really understand what the battery charge rate is calculated or why it is important...what does C8 or C12 mean and how is it calculated?

I'm not going to use a sump pump after all...so I will be using the following electrical devices on a regular basis:
energy efficient refrigerator (12ft3)
about a dozen florescent (10-20W) light bulbs
A newer, energy efficient 46" TV 10-15 hours per week (~120W)
Stereo system (minimal wattage)
A gaming PC, for 2-3 hours a week (500W max)
Modern clothes washing machine & gas dryer
a few other misc items (battery chargers etc...)

Does it seem my system will is adequate to the tasks?

Generator. There is a new style of generator, with auto-throttle speed/power control, that provides DC to an Inverter, and the inverter produces nice, clean AC. The Honda EU-2000 is the typical of that class. They are very quiet, and at less than full load, slow themselves down, saving fuel. Called Inverter Generators. Even Harbor Freight has an inverter model now (but I hear it only sounds like a generator)

Inverter. Many of the higher quality inverters, have a way to feed AC power into it, and it turns into a battery charger. A 95% efficient charger. Most chargers are in the 60 - 75% efficient class, and you pay for it in extra fuel costs, because you need a larger generator. And Outback and Xantrex/Schneider/Conext have inverters that can work WITH a generator, charging the batteries, and then supplying peak surge power if a load comes on that is more than the generator can handle. (Generator Support). Do you have a well pump?

Mike, based on your description above, it seems as if you are suggesting getting a generator which converts DC power into AC, running that to an inverter/charger which converts the SC back into DC to charge the batteries. Wouldn't it be MUCH better to run the DC from the generator directly to the battery bank for charging to avoid efficiency losses in the double conversion?

The other question is about the charge controller, it seems the Outback Power FX3048T has one built in, do I really need the separate charge controller? Why?

My other generator question is of the availability of this type of generator that will run on LP as it is MUCH cheaper than gasoline where I am planning to live?
edit - I just found a store that will sell the EU2000i with a tri-fuel conversion installed for about $1300...would that work?

Thanks again guys, you have been extremely helpful to me

[Mike90250]

Based on the calculations above, how does the shopping cart below look? .

See what the price difference between the 4548 & 6048 is. Lots more capacity for only a few hundred more. or spend the difference on the Conext ComBox.... a really handy piece of gear for recording & logging data for your computer.

Look for what genset is available / repairable at your destination, it's useless if you have to wait 4 months for a fresh fuel filter.

[paulcheung]

Get the Rolls 4000 series S530 batteries, because the price is not much more than the S460. you get 50 more amps and get 12 of those panels instead 8, get 2 charge controller or one Classic 150 which will give you 96 amps charge. the total price will be a little more than $10,000 but you will have a bit more power.

Cheers

[miahallen]

Insolation - for Panama City try summer high of 6.24 kW/m2/day and a winter low of 3.88

http://www.gaisma.com/en/location/panama.html

Look two posts above...I found data showing 4Kw/m2/day low in Belize

So, does this look about right for all my primary components?
solar.JPG

[russ]

Insolation - for Panama City try summer high of 6.24 kW/m2/day and a winter low of 3.88

http://www.gaisma.com/en/location/panama.html

[miahallen]

Excellent, thanks Paul...money is most definitely an issue, so that would bring my total system down to around $10K which is excellent

[paulcheung]

If you use 820 or 925 amps battery you need to use panels produce at least 4000watts to charge the batteries at C12 rate. if you only use 10kwh in 24 hours and most of the heavy load are in the day when sun shining, and you have a generator for rainy days. I would just get 450 amps battery and 3000 watts panels and replace the battery every 3 years or 4 if you carefully maintain these batteries.

If money is not a problem, by all means get these 820 or 925 amps batteries and put the panels to 4000 watts and use two Charge controllers, you will be ok.

Cheers.