Lego renewable energy add on set lego 9688 p an exciting add on set for use with the lego em simple and powered machines set 9686 em order code 70 6053 p p it allows students to learn all about renewable energy sources and is compatible with both the machines and mechanisms portfolio and lego mindstorms education the set features a solar panel turbine blades a motor generator led lights an extension wire and the unique lego energy meter the set includes full colou