The United States is under-investing in clean technology and will ultimately suffer a long-term market share loss if it doesn’t boost spending, according to a report commissioned by the World Wildlife Fund.

Despite having the second largest renewable energy manufacturing sales value worldwide, the U.S. lags behind China, Denmark, Germany and Brazil in those sales when considering the size of its overall economy, the report states.

Clean energy manufacturing sales increased 17 percent in the U.S. in 2011, a positive yet markedly slower pace than the 28 percent surge it experienced in 2010, according to the report.

The Clean Economy, Living Planet report ranks 25 countries based on the 2011 sales of the clean energy technology products manufactured in that country, such as solar panels and wind turbines. China had the largest market, followed by the U.S. and Germany, the report found.

Taiwan was the fastest growing market in 2011, with a 36 percent hike in sales. China earned the number two ranking with a 29 percent uptick in sales. India and South Korea also reported higher growth rates than the U.S. with a 19 percent market increase.

“Other countries are moving on clean technology opportunities and making big investments in the industry, while US policymakers in Washington seems to be content to let all the recent growth in the US wither on the vine by not providing policy certainty and not going after growth opportunities,” said Marty Spitzer, director of US climate policy for WWF. “It’s stable, visionary policy that’s driving the market leaders to the top.”

Main photo credit: nowpicnic/Flickr