A simple idea – cover a 55,000 sports stadium with solar panels, and use them to power (75% of) the lights. This is in Taiwan, ready for the World Games, and, more importantly, Rugby sevens.
When there is no match then the power is fed into the grid – to the tune of 1.14 Gigiwatt hours per year. New Zealand uses about 42,000 GWh per year, so it isn’t a huge amount of electricity – but it is wonderfully sustainable. (I guess in wellington we could use windmills instead)
They built this with no recordable accidents – which is also a stunning achievement.