Portable solar powered power bank

Discussion in 'Power Electronics' started by baxxxter, Nov 28, 2017.

  1. baxxxter

    Thread Starter New Member

    Nov 28, 2017

    I am going to design and build a portable solar powered device which is able to charge a USB device and drive a 4w fan. It also includes lithium ion batteries to store energy in case the direct illumination is not present.
    *Portable ( foldable pv panel)
    *Efficient ( combination of MPPT and PMW)
    *keep the fan running in full speed and charge USB devices at the same time.(Ideally)
    * Prevent the battery from getting over-charged and over-discharged.
    *Satisfy USB devices charging specifications.(assuming be able to charge a mobile phones 3500mah battery within 1 hours in full illumination)
    *relatively low cost.

    I would appreciate it if you guys help me to find out where should I start in calculating . what steps should I take. what information's do I need. Components have to carefully calculated so u have to keep assumption minimal. In the end of the day this is a device that I eventually need to build and it has to work.
    P.S: attached a diagram of the system.
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  2. bushrat


    Nov 29, 2014
    There is a lot to take into consideration when building such project.
    • What solar panels will you be using, are they sufficient in size to provide enough power?
    • What efficiency solar power panels have? 5%? 10%? 20%?
    • How much solar radiation are you getting in your location? http://www.solarpanelsplus.com/workspace/uploads/solar-insolation-us.jpg
    • Is there anything blocking your panels from sun? Trees? Buildings? Cloud cover?
    • Will the panels be always facing south or are they gonna be rotating and auto-tracking the sun?
    • Have you calculated the power loss when converting power from solar panels to 5V USB?
    • Have you considered the price of such project? it may cost you more that you assume.
    Walmart already has something in your parameters, much cheaper.