Alternative-energy investments are hot. But is the reward worth the risk? If a report released earlier this week is anywhere close to accurate, the answer is a solid no. It could be a decade until we see any solid growth.

Alternative energy is hot stuff. Sure energy demand is waning during the economic downturn and crude prices have dropped to a third of their all-time highs, but we all know the bears will eventually fill their stomachs and move on.

At least that is what the folks investing in solar, wind, biofuels and geothermal technology are betting on.

There is a report out this week stirring their ambition. According to research released yesterday by Clean Edge, worldwide alternative energy revenues soared by 53% in 2008 to $116 billion. Not bad, but it pales in comparison to the $477 billion in revenues Exxon Mobil (NYSE:XOM) recorded during the same period.

Fortunately, the industry is expected to grow, but we will have to wait at least a year or so. The current recession has created a nasty speed bump for the “green” economy. Even with Obama’s massive spending efforts, it will be at least a decade until alternative-energy revenues double. Clean Edge estimates the industry’s revenues at about $325 billion by 2018.

Lots of risk, little reward

That is steady growth, but does not come anywhere close to matching the ambition held by so many investors that are planning to get rich overnight thanks to “green” growth.

Looking forward, we cannot be fooled into hoping for too much change. Five years ago investors (or was it politicians?) were claiming clean coal technology was going to power the nation in the near future. We all see how that industry is still lacking its formal introduction to the world.

Read the full article here: In-and-out strategies for alternative investment profits