Designing a Solar Phone Charger
1. Students will be able to design a device that can charge a phone with 4 hours of sun a day. 2. Students will use collected data and be able to support their design – i.e. the data will show that the unit will produce enough energy to charge a phone given it receives 4 hours of sun a day. 3. Students will also be able to calculate efficiency from their power calculations. 4. Students will be able to compare efficiencies of their circuit to others tested in this unit. 5. Students can calculate how much energy 4 hours of sunlight can produce on the solar modules they will use.
This is the culminating activity for the unit “Off the Grid.” Students will be given some restricted parameters around which to design a solar powered battery operated phone (or other USB device) charger. They will charge the AA battery packs that have been using throughout the unit using photovoltaics, and then hook these battery packs into their USB charging device (for a phone, bike light, etc.). This process requires that they combine background knowledge such as voltage and current requirements for their devices they are charging, the function of boost and buck converters, and the correct construction of circuits. Included at the end of this lesson is a written assessment for the entire unit.