How to build a Homemade Super Efficient Portable Solar Generator

    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 100W Polycrystalline Solar Panel.

    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.

    On the back of the system, we have 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 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 circuit that is further connected to battery positive through a switch. The USB ports,12V DC outlet, DC meter all are connected to the respective terminals of the batteries.

    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 an 15A inline fuse and a current transformer. The ammeter is connected to current transformer and the 110V outlet.

    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. Amp meter tells how many amps we drawing 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 inverter, case temperature sensor, cooling fans , AC power outlets. We install a key and power up the AC side of the system. There is two fans on the back that push air in and draw air out of the case to keep the AC DC inverter cool.

    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 emergency 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 build up 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 cables to transfer the power back and forth between the batteries. These type of batteries require less maintenance. Also installed a wooden frame with exact dimension of 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 , 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 a SAE 2 pin port.



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