The chairman of Germany’s largest luxury carmaker, Daimler-Benz, braved boos and a frosty reception as guest speaker at a Greens party congress on Sunday to tell delegates he too wants CO2-free cars on the roads. Dieter Zetsche, whose company is demonized by many Greens, said the firm had not missed the boat developing electric cars and said it backs climate protection goals. But he dismissed their call to ban the sale of new cars powered…