The partnership between Würzburg and Mwanza, which has existed since 1966, was expanded in 2011 to include a climate change partnership. Various climate protection and adaptation projects are aimed at the sustainable use of solar energy. In Mwanza, for example, pilot solar arrays have been installed on municipal buildings, which not only cover the energy requirements of the buildings themselves, but also feed excess energy into the public grid. A further flagship project involves
renting out solar fishing lamps at Lake Victoria because the kerosene pressure lamps commonly used for night fishing produce around 15,000 tonnes of CO2 annually and are a source of considerable damage to the environment. The solar lamps also provide financial relief to fishermen, who otherwise have to spend up to 50 percent of their income on kerosene and maintenance. Medical projects such as the fight against schistosomiasis and the promotion of sustainable tourism round out the partnership.
On 14 November 2018, the jury of the German Sustainability Award will select the top 3 entries and the winner.