Oil giant Chevron recently wrote down over $10 billion in fossil fuel assets — things like natural gas projects and oil fields that are losing value. Some analysts suggest a glut of natural gas supply is driving the move, but many observers see a deeper climate change connection: the need to cut emissions is changing consumer demand. “Investors are quite concerned that companies like Chevron that are producing fossil fuels will continually be caught with assets that they can't sell. If utilities can buy solar at a cheaper rate than natural gas, that will impact Chevron,” said Danielle Fugere, president and chief counsel of shareholder advocacy group As You Sow.