When a company like Shell, with a history of extracting carbon from the ground and burning it, says it wants to become the biggest electricity producer in the world, it is best for onlookers to begin with at least an element of suspicion. That suspicion has been well and truly aroused this week when Shell has come out with a plan to spend $300 million, effectively on carbon credits. The press release says it will invest in natural ecosystems as part of its strategy to act on global climate change. But $300 million over 3 years, is $100 million a year, and as a percentage of its $388 billion revenue, it is less than 0.003%, and of positive cashflow around…