Portable - Solar Tracking Mounts
As long as the earth rotates the Sun will track the sky from East to West. Considering that a solar panel is only producing maximum power when it is facing the Sun and at right angles to the Sun. A solar panel positioned at a fixed angle will only producing optimum power for a very brief portion of the day. If these panels were turned every few minutes they would be much more efficient. But are you going to diligently change the angle of the panel and redirect it toward the Sun every hour? Probably not. That is why adding a solar trackeing mount makes so much sense. A small 50 watt panel that tracks the Sun will harvest more power than a large 50 watt panel at a fixed angle.
The system pictured above will track the Sun from sunrise to sunset. This system is constructed with aluminum extrusion, a sturdy set of wheels, a single axis tracker to control azimuth. The inclination is adjusted manually because it is portable and it will not go unattended for any length of time…or shouldn’t.
This particular system has a 50 watt solar panel, a solar charge controller, an affordable solar tracking component and a 12v dc actuator to position the panel. Simply connect a storage battery to the quick-connect wires and charge your storage battery. If you only require DC power and you happen to use only LEDS to provide light through the evening you would have all that you need. However, most folks require AC power for radios, TVs, coffee pots and perhaps even a refrigerator. In this case you will want to purchase additional batteries to create an array and connect them to an inverter. Or, you can purchase any number of portable power packs on the market that will combine them in a nice compact and light-weight assembly. Naturally, you can purchase more substantial power packs like the Goal Zero.
Before you decide to build your own system it is important to understand that this system will easily produce between 2-4 amps on a good solar day. So on an ideal solar day you may only produce 40 amps, this is what you have available (more or less) to replenish the storage battery.
If you are using a 100 AH (ampere hour) lead acid battery you can expect to only be able to discharge this battery to within 60%, or about 60 AH. That is because lead acid batteries should not be discharged below this level without possible damaging the cells. This simply is a rough rile-of-thumb and is not strictly adhered to. It should also not be charged too quickly for fear of warping the plates and potentially shorting them which can produce an arc. Given that Hydrogen is generated during the charging process it is best to avoid an arc of any kind. This can be a catastrophic failure with dangerous results. I recommend using LiFePO4 batteries(Lithium Iron Phosphate) in their place, they are safer, incredibly light and can be charged and discharged over a wider range.
I am no expert in these matters I am simply a guy that has incorporated readily available components and developed a means of putting them altogether to produce a small, lightweight portable solar tracking system. If you are feeling experimental and feel comfortable spending about $350-450 to build a system like this then continue to follow this Blog and my website at medomyself.com.
The frame work is made with aluminum t-slot extrusion, it is perhaps my favorite toy in the shop. I use this and all of the supporting hardware to make most of my projects. For this project you can modify the size of your mount a bit. Over the years I have greatly streamlined my design to use the least amount of extrusion to reduce the weight. Remember this is portable and keeping it light and mobile is the key.
You will need a metal saw blade well suited for cutting aluminum otherwise you risk melting the aluminum as you cut. If the blade is too aggressive you risk serious injury. The material cut list can be found here.
Here is a short video that puts things into perspective.
In future posts I will provide information on a few other solar related projects. I felt that a lot of the solar powered generators (essentially a battery, charge controller, AC power inverter in a box) were over priced and were heavy. The weight is primarily due to the lead acid battery which is rather dated technology…in my opinion. The new age in batteries is with LiFePO4 batteries. About ¼ the weight, deeper cycling and faster charging.
