Otteh Edubio, a former pupil of Schiller Gymnasium, returned to inform pupils in the LK (advanced) courses of English and Biology about the sustainable developmental goals of the United Nations, which looks at combining solutions for several problems in the world. One approach is to offer decentralised mesh grids which supply electricity obtained by renewable energy. Enough energy is generated by these grids, so that communities which formerly had no access to a national grid of electricity, can now use appliances which require more energy, such as refrigerators and microwaves.