This project goes over the build of a Homemade medium-sized and moderately priced portable solar power generator that is designed to be powered by a 100W Polycrystalline Solar Panel.
STEP 1 :CHOOSING A CASE
The case for this portable system is from Plano sportsman, quite sturdy and rugged that a typical container. Costs about $25. It has a nice top with handles that latch it down.
STEP 2 : CONNECTING THE BATTERY
On the back of the system, we have a two-pin SAE port that allows the energy from the solar panel to come into the system. It directly goes into a 30A solar charge controller. The negative from the charge controller is connected to the negative of the batteries. The positive is connected via a switch to the positive of the battery. The negatives and positives of the batteries are connected to each other. The negative of the inverter is connected to the negative of the battery. The positive is connected to a battery switch off the circuit that is further connected to the battery positive through a switch. The USB ports,12V DC outlet, and DC meter all are connected to the respective terminals of the batteries.
STEP 3 : CONNECTING TO AN AC OUTLET
To connect to the AC outlet from the inverter, we take a 3 wire extension cord which can be bought from the local hardware store. The negative end of this wire is connected to the negative of the shallow box AC outlet and the positive is connected via a 15A inline fuse and a current transformer. The ammeter is connected to the current transformer and the 110V outlet.
STEP 4 : ACCESSORY PORTS
On the front of the system, we have the accessory ports including a 12V power indicator, 2 USB ports with 5V one amp and 5V 2.1amp, 12V outlet, AC Voltmeter, and ammeter. The Amp meter tells how many amps we draw out of the system using various appliances. This can help us understand how much solar power is being generated during the day versus solar power being utilized from the system.
The whole system is turned on a 12V master key switch that activates the inverter, case temperature sensor, cooling fans, and AC power outlets. We install a key and power up the AC side of the system. There are two fans on the back that push air in and draw air out of the case to keep the AC DC inverter cool.
STEP 5 : CONFIGURING THE INVERTER AND CHARGE CONTROLLER
Inside we have a deck tray made from backboard material available at Home Depot. We have installed a 400W pure sine wave inverter, a 30A MPPT solar charge controller and a 12V LED light on them, also has four vents that allow air to circulate through the top portion of the case as well as through the bottom. The vents keep the batteries cool and allow any off-gas buildup from the batteries to pass it through.
Here the inverter has a built-in automatic shutdown feature that ensures that the batteries are not discharged to a significant level. So it is safely connected to the batteries.
Once the deck tray is taken apart, we have 2 55AH AGM sealed batteries that are wired in parallel to a 2 AWG cable to transfer the power back and forth between the batteries. These types of batteries require less maintenance. Also installed is a wooden frame with the exact dimension of the inside of the case to keep the batteries in place and keep them from moving around.
To protect all the components we have fuses ranging from ANL 50amp fuses between the inverter and the battery, and inline 30amp fuse between the solar charge controller and the batteries.
To attach jumper cables we have an option for external heavy-duty battery terminals. To connect to an AC float charger we have added an SAE 2 pin port.
Image Credits : Jim Fisher DIY Portable Solar Power
