After welcoming Tony as a new member, we started the session following on from last time, with a quick review of rotary electric motors.  We saw two working examples of how automatic on/off and directional control of small motors can be achieved with only simple switches.

We then moved on to the main topic in this session: Domestic microgeneration, a.k.a. 'green energy'.  We looked at how solar panels worked and the physics of the photovoltaic effect.  We looked at the various jobs a hybrid inverter does to convert DC into AC, control battery charging and manage power import and export.  Finally we considered the electrical requirements for an EV charger, both the physical infrastructure and how they interact electrically with the other components of an integrated domestic microgeneration system.

To finish, Richard bought along a wooden marble-run toy, that he would like to motorize.  It is to have a press-button to turn it on, and should switch itself off after a certain length of time.  In future sessions we will consider the design of an appropriate gear-train to obtain the correct speed and toque from a small motor, and also the design of the electronics for the on/off timer.