A battery’s storage capacity is frequently expressed in terms of amp-hours [Ah]. The larger the number, the larger the capacity—also the heavier the battery. If the concept of battery capacity, expressed as amp-hours is difficult to grasp, think of a battery as a lake. The larger the lake, the more it takes to see a significant change in its level. I am using an 18Ah Sealed Lead Acid [SLA] Battery. In addition, using battery chargers, I can also store the sun’s energy in other batteries. To the right of the battery in the photo above, you see a AA/AAA Ni-MH battery charger. During yesterday’s test, I charged 4 AA and 4 AAA batteries. At the end of the day, my 18Ah battery did not need additional charging to be topped off. I have been asked why SLA versus a lighter battery. Comment # 1 has the question and my reply.
A solar charging system can use a charge controller to keep the battery from being overcharged or being excessively drained. I have such a controller. Think of it as a dam on the lake where you can maintain water levels [amp-hours (charging)] through its controls. The solar controller uses electronic gates. My controller has the following features:
- Auto charge and cut-off power when 12V SLA battery is full or low
- Protect battery from being overcharged and over-discharged to increase battery service life
- LED display battery storage level
- Built in fuse to protect short circuit and wrong polarity connection
- Moisture proof design for outdoor use
Then, there are meters that allow me to view various levels. I am using 2 DOC Wattson Meters. One monitoring charging input [the solar panels] and the other, the battery. The meter measures 7 DC values:
- Amp-Hours: (0 – 6554)
- Kilo Watt-hours: (0 – 650)
- Amps: (0-100 peak)
- Watts: (0 – 6554)
- Peak Amps & minimum Voltage ("sags")
- Voltage: (0 – 60)
Although the sun’s energy is relatively free, I think I should use it responsibly. By that I mean, I should not consume power from the battery because I can easily charge the system [at no apparent cost] in my hotel/motel room. Doing so increases the carbon footprint and is less GREEN than being conservative. Please see my comment #2. As best I can, I want power to keep my lighting, navigation, and communications systems working. I’ll use mechanical power to maintain the iPhone 3GS charge. I’ll post about that system after I write about the output of the stored solar energy, likely tomorrow, Friday, 02/05.
My BROL Quad [Fargo] Setup Thread
Remember this graphic…