Energy is the most important resource on Earth. It is estimated to account for nearly 10 per cent of the world’s economy.1 Over more than a century the sector has grown to become a tightly controlled behemoth, much of which is in the hands of a small number of multinational corporations. Over the last 40 years, however, the growth of renewable energy has started to challenge this status quo. For the fi rst time, it is possible to generate high-grade, sustainable electricity; that is, to generate electricity without depleting our fi nite mineral resources. Solar power is central to this ‘democratisation’ of the world’s energy.