The future of energy supply: where we are, where we should go

A brief analysis of the present energy system will be illustrated, with particular emphasis on unconventional fossil fuels and renewable energies, showing that the latter - and particularly solar energy - is the radical solution to the energy conundrum. To foster the transition to a sun-powered world a few key strategies have to be implemented: (1) increasing the share of electricity in energy end use; (2) establishing technologies for the manufacturing of solar fuels; (3) enhancing the efficiency in energy production and use; (4) reducing the energy consumption in affluent countries; (5) recycling of the equipment used for converting renewable energy flows, in order to secure materials available in very limited supply (e.g. precious metals) to future generations. The energy transition compels the mobilization of huge human and economic resources in several scientific and technological fields, in connection to a knowledge-driven political action that must govern what is probably the most complex challenge ever faced by mankind.