Hi grill , I ' m a hot dog and want to be on you . <| sep |> I actually disagree with your assumption . Disagree with the Google engineers with a billion dollar budget to work on renewable energies . We decided to combine our energy innovation study ' s bestcase scenario results with Hansen ' s climate model to see whether a 55 percent emission cut by 2050 would bring the world back below that 350 ppm threshold . Our calculations revealed otherwise . Even if every renewable energy technology advanced as quickly as imagined and they were all applied globally , atmospheric CO 2 levels wouldn ' t just remain above 350 ppm they would continue to rise exponentially due to continued fossil fuel use . So our bestcase scenario , which was based on our most optimistic forecasts for renewable energy , would still result in severe climate change , with all its dire consequences shifting climatic zones , freshwater shortages , eroding coasts , and ocean acidification , among others . Our reckoning showed that reversing the trend would require . radical technological advances in cheap zerocarbon energy , as well as a method of extracting CO 2 from the atmosphere and sequestering the carbon . Those calculations cast our work at Google ' s REC program in a sobering new light . Suppose for a moment that it had achieved the most extraordinary success possible , and that we had found cheap renewable energy technologies that could gradually replace all the world ' s coal plants a situation roughly equivalent to the energy innovation study ' s bestcase scenario . Even if that dream had come to pass , it still wouldn ' t have solved climate change . This realization was frankly shocking Not only had REC failed to reach its goal of creating energy cheaper than coal , but that goal had not been ambitious enough to reverse climate change . e n g i n e e r s e x p l a i n w h y t h e y s toppedrdinrenewableenergy