Lately, we’ve been getting quite a few emails from readers asking us for advice about which companies to invest in. While we appreciate the fact that you seem to value our opinions and insight, it’s just not our business to make those kinds of recommendations. Your best bet is to reach out to an educated investor analyst.

This got me thinking back to when I first began writing for Biomass Magazine over seven years ago, when I interviewed some executives from a company called Mantria Industries, which was supposedly making biochar. Here are a couple of excerpts from the story:

Mantria Industries LLC recently opened a biochar production facility in Sequatchie County, Tenn. The operation, which utilizes a flash carbonization technology, was developed at the University of Hawaii…

Mantria CEO Troy Wragg said the company has also contracted 30,000 square feet at a distribution center in Atlanta, Ga. “We have an advanced bagging system in place so we can quickly get the product into the market,” he says. “Material handling is one of the biggest costs in any type of fertilizer or soil amendment market, so that’s one of the things we’ve stepped up on-providing the same type of standards the pot ash or fertilizer industry has, but creating the actual logistical distribution and shipping capabilities that other companies don’t have.”

Wragg says the company already has contracts in place for its EternaGreen biochar, and sees the industry gaining momentum. “I believe over the next two to five years, we’ll really start to see a boon for biochar, he says. “From 2011 on, we’re going to see biochar become one of the largest commodity products in the world, and I say that only because right now our current policies nationally and internationally are focused on energy playing a role to combat climate change when, in fact, agriculturally, we stand a chance to make a bigger impact.”

So fast-forward to—if I remember correctly—less than a year later, and here’s the headline of what I guess you could consider a follow-up piece that I wrote:

 Biochar company Mantria charged with investor fraud 

Needless to say, I didn’t feel great about that, and shortly thereafter ended up authoring apiece on avoiding green scams.

For that, one of my sources—John Gannon of the Financial Industry Regulatory Authority—said that interest in biochar as a means to sequester carbon and as a substitute for charcoal had reached new heights in recent years, thus making it appealing  to scammers. “When an area is hot for investors, scamsters understand that and so that’s where they target their scams,” he said.

Coindentally, less than a year later, another biochar company I had interviewed numerous times and met while it was exhibiting at some trade shows—New Earth Renewable Energy LLC—got caught and charged with fraud as well.

Anyway, this week I did some research to learn of the final results of the Mantria case. And, unbelievably, it is being labeled as the biggest green scam in American history, a $54.5 million Ponzi scheme. Run by some recent college grads. From what I’ve gathered, the majority of their victims were elderly persons or those near retirement.

And a side note: although the facility Wragg told me a bout in the interview did exist, according to the investigation, it did not produce any biochar.

I could go on, but I’ll get to my message here. We’re obviously advocates for the bioenergy industry and want to see companies succeed, but we can’t tell you which ones will. What we do recommend is being careful out there, especially if you’re looking to funnel dollars into the sectors that are “hot” right now. Lots of good guys out there making things happen, but, as there always has been and will be, there are some bad apples amongst them.