MIAMI - Within hours of landing in Brazil in late 2007 on a trade mission, Gov. Charlie Crist announced a $182 million investment by a Brazilian company to provide clean energy for the state capital.

"I am confident today's announcements are only the first of many new partnerships and new opportunities," Crist said.

But within months the deal had fallen through amid allegations of fraud, and a Tallahassee start-up was out $140,000.

As Congress gets ready to parcel out billions of dollars to create what President Obama likes to call "green collar jobs," energy analysts warn of the dangers of a rush into territory already littered with failed investments.

"Yes, there's gold in green," said Susan Glickman, southern regional director for the Climate Group, which builds bridges between business and government to promote a cleaner planet. "But not all green is gold."

The Tallahassee deal looked good on paper. Green Power Systems had already secured a 30-year power-purchasing agreement from the city of Tallahassee to turn nonrecyclable municipal solid waste into electricity using super-charged heat in a "plasma arc" incinerator.

"We are big believers in this technology," said Ben Cowart, power marketing manager of the city of Tallahassee, which owns the local utility serving 120,000 residential customers.

All that was needed was investors to come up with the millions it would take to build the facility.

Wealthy Colombian brokers in Miami Beach put Green Power Systems in touch with an Argentine businessman, Alberto Grosso, president of Controlsud International, purportedly the Brazilian branch of a multi-national firm with $10 billion in investor capital.

After several meetings, Controlsud agreed to put up $182 million.

"They said they had a whole world of financing behind them," said Ingo Krieg, president of Green Power Systems. "Turned out they were just stringing us along."

In the process Krieg was asked to pony up $140,000 to pay for a "risk assessment," outlining the company's business plan for investors.

Controlsud was never clear on who its investors were, Krieg said. "They said something about a Baron somebody in Germany and a big insurance company," Krieg said.

It turns out Controlsud had a history of offering large investments in green energy throughout Latin America and walking away from deals after payment of risk assessments, leaving a trail of angry former business partners.

A $342 million project to double ethanol production in Colombia was signed by Controlsud in December 2007, with the backing of the Colombian and U.S. governments. At a signing ceremony in the presidential palace in Bogota, Grosso was photographed with President Alvaro Uribe and U.S. Ambassador William Brownfield.

"They took us for a ride," said Juan Manuel Hernandez, president of the Ethanol Consortium Board, who signed the Colombian agreement with Controlsud, and put up $180,000 for a risk assessment. "Now we are broke."

In 2007, Controlsud also was part of an aborted $6.5 billion deal to build "pollution-free" oil refineries in Panama using plasma arc technology.

In a phone interview Grosso of Controlsud confirmed the deals had fallen through, but blamed the global economic meltdown.

He reiterated that his company was backed by major European banks and private investors. Among them he named Germany-based Allianz, one of the world's largest insurance and banking groups, as well as the private funds of Baron August von Finck, heir to a multibillion-dollar banking fortune.

Contacted by the St. Petersburg Times, Allianz said it could not confirm any relationship with Controlsud or Grosso. The office of von Finck emphatically denied any association.

"Mr. August von Finck does not know this company, and he is astonished about your report," his office responded in an e-mail.

Asked to explain, Grosso, who is vacationing in Argentina, said he was not surprised.

"That's their normal business policy to deny these things," he said, before contradicting his previous comments by saying he never claimed to have the personal backing of von Finck or Allianz.

Before Crist arrived in Brazil, the organizers of the state's trade mission looked into Controlsud and found nothing amiss.

"We did some due diligence on them," said Manny Mencia, head of International Trade and Business Development at Enterprise Florida, the not-for-profit government business partnership that organized the trip. "We didn't see anything out of the ordinary. It seemed good as gold."

Green Power Systems and the city of Tallahassee remain confident that the project will go ahead. Krieg is looking for new financing. "We hope to announce some very good news soon," he said.