Ernsting examines the most advanced uses of renewable energy as practiced in Scotland and Denmark and reaches the following conclusion:
Any meaningful response to climate change must involve rapidly phasing out fossil fuel use while protecting remaining ecosystems, including healthy soils, and restoring and allowing as many damaged ecosystems as possible to regenerate. Wind and solar power, depending on where they are sited, can be amongst the ‘lowest-impact’ and ‘lowest-carbon’ forms of energy, so their expansion will indeed need to be supported. But ‘lowest-impact’ is far from ‘low impact’, and lower carbon is nowhere near ‘zero carbon’. Nor, as we have seen, is it realistic to expect such forms of energy to replace current fossil fuel use, and certainly not in the time necessary to prevent the most disastrous effects of climate change. Moving towards a low-energy society remains the only path for avoiding a climate catastrophe. [my emphasis]This conclusion obviously means that we must end capitalism and move immediately to a sustainable social system if we as humans are to have any hope of survival.