In this COP26 special, we look at the immense challenge of making energy carbon-neutral. As the International Energy Agency records a surge in coal use and record jump in greenhouse gas emissions, its head, Fatih Birol, tells us what he wants from the climate summit. And the CEO of UK electricity market disruptor Octopus Energy says data will be the key to switching to renewables. Plus a view on COP26 and climate change from young Peruvian @InesYabar.