The solar trailer project got me thinking – Keith had had the idea of incorporating a pedal-powered generator to the trailer to demonstrate to people in terms of human effort how much energy is required to to do certain everyday tasks (such as brewing a cup of coffee), and how this relates to the amount of energy being generated by the solar panels.
After searching the web, I found that there weren’t many such devices available off the shelf, and the ones that were were very expensive, so I decided to have a go at building one my self. I bought a second-hand “turbo trainer” for £15 and salvaged a motor from a scrapped washine machine (many motors can be used to generate electricity if reversed). After making a crude test-rig, I connected up my bike to the motor and managed to get a promising 30volt output. To test the wattage, I then connected the motor to a 60w lightbulb. Even at max rpm from the pedals, there was no light! I scratched my head a bit, then found this trailer board lying around in the garage, so connected up to one of the 12v bulbs, which you can see lit up in the photo. I later calculated the output at a whopping 5w, so not very useful but it’s a start!
Next step is to try a few different generators and connect up to a battery for storage. Think I will try a car alternator first.