The four-day event in Husum, on northern Germany's windswept North Sea coast, had just 743 firms showing off their wares last time it was held in 2008, and the exhibition space has been increased by 40 percent.
Although the wind energy market's prospects are seen as healthy in the medium term, participants in Husum said that the number of wind turbines installed is set to fall this year, due largely to a slowdown of the US market.
In host country Germany, meanwhile, renewable energy firms are angry at plans by Chancellor Angela Merkel's government to postpone the date when Europe's biggest economy abandons nuclear power.
Merkel wants to extend the lifetime of Germany's 17 nuclear reactors by an average of 12 years beyond a previously scheduled shutdown of around 2020 as a "bridge" until renewable sources of energy such as wind and solar suffice.
"The government's plans are torpedoing the development of renewable energy," said Hermann Albers, head of the German Wind Energy Association (BWE).
Anti-nuclear protesters have vowed further demonstrations in the coming weeks after tens of thousands rallied in Berlin on Saturday, while opposition lawmakers have said they want a referendum on the issue.