Provided by Dow Jones By Dominic Chopping Vestas Wind Systems AS on Wednesday posted an unexpected first-quarter net loss but backed full-year guidance as it pledged to make up lost ground later this year. The Danish wind-turbine maker posted a net loss of 61 million euros ($73.3 million) from a loss of EUR75 million a year earlier, missing an analyst consensus of a EUR9 million profit, according to a FactSet poll. Revenue fell 12% to EUR1.96 billion compared with the consensus view of EUR2.56 billion, driven by lower wind turbine deliveries, supply chain constraints and a negative impact of around EUR100 million from foreign exchange rate translations effects.