After a few months experimenting with solar energy generation in my spare time, I finally was able to start using the system to power up some of our lighting requirements. We have about seven CFL bulbs lighting our right of way and part of the perimeter fence at night. This is controlled by an optical switch that automaticall turns on the lights when it is evening and turns them off in the morning.
I measured about 120W of power drawn from the battery for all the lights. Assuming the lights are on 12hours, I will be saving about 1.44kWhr per day or about 43.2kWhr per month. At Php8.5/kWhr, this amounts to Php367/month. This doesn’t seem much but this actually means that I only need to increase battery storage capacity and also solar panel generating capacity and I can increase my savings gradually until I get free electricity.
The lights at our right-of-way and part of the fence/perimeter are now powered by solar energy.
My solar panel, after checking it again, actually has a capacity of 128W and not 100W as I mentioned before. This means I have only less than 10W reserved generating capacity to allow for cloudy days. So I will change some of the bulbs to a slightly lower power rating in order to keep the power consumption at about 80W.
I also plan to add another set of batteries to make my total storage capacity of 400AH because during brownouts, I can also use the system to power up my network equipment that consumes about 230W. I can avoid using the generator if the power interruption is only for short periods. This is handy for night time power interruptions because the generator doesn’t help me get a good sleep.
In the next week, I will see how my setup performs in various conditions. I will also start to source out solar panels to increase my generation capacity. At this point, I can add solar panels for up to 2kW generating capacity which is the maximum capacity of the charge controller. So it is just a matter of acquiring the panels to start generating a few thousand pesos savings monthly.
Solar Power Tips:
- Lead-acid batteries should not be left discharged for long periods. This can permanently damage a battery when the chemical reactions causes sulfation. Desulfation is a process of forcing the batteries to recover from being discharged for long periods. Some battery chargers include the desulfation action when the battery is charge near full capacity. Good charge controllers should include a desulfation or equalization charge in its process of charging batteries to help ensure long battery life.
- Lead-acid batteries will need to be topped up with distilled water every 6 months or so because during charging, the battery’s chemical reactions will release hydrogen and oxygen. Adding distilled water will enable the battery to do the chemical reactions to the optimum level.
- Battery fluid (sulfuric acid solution) should not be added to the lead-acid battery.