Guardian: Vestas, the world’s largest wind turbine maker, brought some cheer to a renewable power sector struggling against the credit crunch. The Danish company today reported a better-than-expected 51% rise in its full-year operating profit and maintained its 2009 sales and profit forecasts. But it admitted that profit growth seen over the last three years would slow during the next 12 months and said costs would be cut back if there was improvement in demand over the next …