RV Solar Design Requested

OK folks, your design assistance would be appreciated.

I have a Ford E350 extended van with a 20"-tall fiberglass top on which, five years ago, I mounted four PV solar panels. My previous solar charge controller failed and, without naming names, I wasn’t all that impressed with it anyway. So, I now have the opportunity to re-think and re-design my PV solar system.

My two primary electric loads are as follows:

1. Engel Combi Fridge Freezer combo
Model: MT60
Volume: 34 Qt Fridge / 26.5 Qt Freezer
Power Source: 12V DC / 24V DC / 110V AC
Power Consumption: Variable from 0.7 - 2.8 Amps (12V DC)

Daily Amp Hr Usage 24x4= 96 Amps per day
So aren’t watts 12x4= 48 W
Engel: Daily Watt Usage 24x 48= 1152W

http://www.engel-usa.com/index.php?page=shop.product_details&flypage=vmj_genx.tpl&product_id=26&category_id=1&option=com_virtuemart&Itemid=59

Note: I have had the Engel for 5 years. My actual experience, regardless of what the manual says regarding duty cycle or amp usage, is that my BMV 600S battery monitor says that it draws 4 amps continually around the clock at least when outside temperature is 100F.

2. Webasto Dual Top diesel furnace/hot water heater
Model: RHA-100
Power Source: 12V DC; operating range 10.5 to 15V DC
Current Input at 12 V DC: 0.5 to 7 A
Power Consumption in use: 15 to 65 W
Power Consumption standby: >1 W

Daily Amp Hr Usage: 6x7= 42 Amps/ day
Daily Watt Usage
24x(15+65/2=40)x 24= 960 W

Similar to:
http://www.webasto-outdoors.com/heating/dual-top/dual-top-evo-6.html


Battery: I have a 250 Amp Hour sealed AGM house battery (electrically isolated fr the starting batteries)
Universal Power Group
UB-8D AGM 9925089 250aH 12V DC
20.5" x 10.5" x 10" 167 lbs.


PV Solar Panels:

I have four BP 380J panels flat mounted on the roof (and can fit and would like to add a fifth)
BP 380
Rated power (Pmax) 80 W
Power tolerance ± 5%
Nominal voltage 12 V
Maximum power (Pmax)3 80 W
Voltage at Pmax (Vmp) 17.6 V
Current at Pmax (Imp) 4.5 A
Warranted minimum Pmax 76 W
Short-circuit current (Isc) 4.8 A
Open-circuit voltage (Voc) 22.1 V
Temperature coefficient of Isc (0.065±0.015)%/ °C
Temperature coefficient of Voc -(80±10)mV/°C
Temperature coefficient of power -(0.5±0.05)%/ °C
NOCT (Air 20°C; Sun 0.8kW/m2; wind 1m/s) 47±2°C
Maximum series fuse rating 20 A
Maximum system voltage 600 V


Additional facts:

My home base is Sacramento, CA. My usage is usually around Latitude 38.

The Engel Combi Fridge Freezer runs the hardest in the Summers camping, etc. when the outside temperatures are 90 to 100F during the day. Again, my actual experience, regardless of what the manual says regarding duty cycle or amp usage, is that my BMV 600S battery monitor says that it draws 4 amps continually around the clock at least when outside temperature is 100F.

The Webasto Dual Top diesel furnace runs the hardest in the Winter (I use the sportsmobile as an rv every weekend at Kirkwood Ski Resort where the outside temperatures can run from -17F to +50F.


My Load calculations:

You shouldn’t have to do my homework. I should have to do that, but could you check it? I am not a numbers person and I probably screwed up something below, or my assumptions are wrong for my flat panel mounted panels for my latitude, or I didn’t even see the elephant in the room which is obvious to you. Accordingly, your correction of my homework as well as any additional comments and suggestions would be greatly appreciated.

1. Assuming I will run both the Engel and the Webasto during the Winter:

Load: 96 A (Engel) + 42 A (Webasto) = 138 AHr/day

Four PV Panels (what I have now):
Voltage at Pmax (Vmp) 17.6 V
Current at Pmax (Imp) 4.5 A
4.5 A x 4 = 18 A derate 50% = 9 A
9 A x 10 hours of effective sunlight/day = 90 AHr/ day

This leaves a deficit of 48 AHr per day (90-138=48 AHr). Thus, 4 panels will not be able to replenish the usage via the PV array each day. Accordingly, running a generator will be required.

Five PV Panels (max that can fit on the van roof):_
4.5 A x 5 = 22.5 A derate 50% = 11.25 A
11.25 A x 10 hours of effective sunlight/day = 112.5 AHr/ day

This leaves a deficit of 25.5 AHr per day (112.5-138=25.5 AHr). Thus, even 5 panels will not be able to replenish the usage via the PV array each day. Accordingly, running a generator will be required.

2. Assuming I will run only the Engel in the Summer:

Load: 96 A (Engel) alone = 96 A/day

Four PV Panels (what I have now):
4.5 A x 4 = 18 A derate 50% = 9 A/Hr
9 A x 10 hours of effective sunlight/day = 90 AHr/day

This leaves a deficit of 6 AHr per day (90-96=6 AHr). Thus, 4 panels would not replenish the usage via the PV array each day. Accordingly, running a generator will be required.

Five PV Panels (max that can fit on the van roof):
4.5 A x 5 = 22.5 A derate 50% = 11.25 A/Hr
11.25 A x 10 hours of effective sunlight/day = 112.5 AHr/day

5 panels would replenish the usage via the PV array each day. Accordingly, running a generator should not be required


Questions:

Assuming that money is no object (which it is not but I want purely electrical advice) what is the best solar charge controller for my needs?
Would an MPPT charger actually (rather than theoretically) increase my charging amps per day?
Should I wire my panels in series or parallel?
(I previously wired them in series but I can easily re-wire them in parallel.)
In the event that I have killed my battery because it is five years old and I have undercharged it and over-discharged it, what would you recommend. I can fit golf batteries in parallel or in series.
Finally, please correct my abbreviations/nomenclature.
Do you have any other suggestions?

Thanks. Your time and knowledge would be greatly appreciated.