I have no personal experience with installation, operation or maintenance of off-grid systems, though I have studied renewable energy for several years. My suggestion would be to find the technical data for each peice of equipment you currently have in use, such as battery AHr ratings, Charge controller output, etc. Then, I would calculate the total amp/hour per day consumption (how much energy you will use) and compare it to what your equipment is capable of producing. Keep in mind that when using power inveters you will not have 100% efficiency. Inverters are rated at approximately 80-90% for sinewave, and 85-95% for modified sinewave, depending on the percentage of rated output (or load).
Other things I would consider are: how many hours per day of sunlight multiplied by wattage output os PV panels to give watt/hours/day of battery charging and load carrying capacity. Having more than enough battery capacity won't hurt as days with reduced charge output will occur. I also would suggest that whatever your calculated daily watt/hr or AHr useage is, multiply it by 1.5 to 2.0 and you'll stand less chance of experiencing discharged battery banks.
Regarding batteries, I have read mixed feelings from various sources about the acceptable discharge state or percent of charge prior to recharging. It would apear to me that 50% state of charge is probably a good time to recharge. So, if you have a 195 AHr battery, I would plan for only using 95-100 AHr before charging, or 1/2 the rated capacity. Fully discharged batteries are can be dificult to recover, especially flooded lead acid type. A solar powered battery desulfator would be a good investment for proper battery maintenance. I have a computer controlled smart charger/desulfator for automotive batteries and thus far have recovered at least a dozen batteries in the past 3 years.
The best thing you can do is educate yourself with as much information pertaining to your equipment as possible and then you be able to make the best decision on a course of action. Good luck. |