Humming along in a green SUV

In 2000 Jonathan Goodwin, a self-described 'gearhead', bought his first Hummer, an old H1, in the US state of Colorado.

"The thing did eight miles to the gallon (3km per litre) and nought to 100kph in about two days," he recalls.

On his drive home to Kansas, it broke down three times. The first morning home with it, he decided to run the Hummer through the pond behind his house. "It was supposed to be waterproof," he says. This one wasn't. He hit the water at 50mph and turned his new vehicle into a submarine. The engine died.

Rather than fix the engine, he replaced it with a new Duramax diesel and increased the fuel economy to 20 miles per US gallon (equivalent to 24 miles per Imperial gallon), tripled the horsepower to 600 and quadrupled the torque to 1,200ft lbs. Driven by his quest for more power and less consumption he had inadvertently stumbled across a solution for the Middle East's SUV-loving masses. The byproduct of the system he installed is lower emissions - a greener output for these thirsty beasts. "Now we can have our cake and eat it," he claims.

Today Goodwin drives a green Hummer H2 that he transformed from a 325hp, 10mpg gasbucket into a 500hp, 25mpg, 900ft lbs of torque white-knuckle ride, using the Duramax 6.6 litre engine that he runs on biodiesel - in this case, B100 canola oil. In addition, with the systems he has designed, the engine will run on multiple types of vegetable oil, CNG (LPG) or hydrogen.

With basic conversion costs starting at around $27,000 (BD10,164) it's not for the budget commuter, but with the double jackpot of increased power and greater efficiency he's not short of orders as co-founder of SAE Energy, which works at the forefront of alternative fuel research.

He has transformed gas- guzzling SUVs into fuel-efficient high-performance green machines and is now converting vintage autos to biodiesel and electric hybrids for the likes of California governor Arnold Schwarzenegger and rock legend Neil Young.

What Goodwin managed will become increasingly important to carmakers in the US, where the Corporate Average Fuel Economy (CAFE) bill means on average a company's cars must manage at least 35 miles per US gallon by 2010. Mercedes Benz was recently hit with a record $30 million fine for only managing 24.8mpg, short of the 2006 limits of 27.5mpg.

Goodwin's take on the struggling Detroit car industry is typically straightforward: he feels the American carmakers should be fighting for their lives. "It would be so easy to take a well-established auto company and turn it cutting-edge. The technology already exists, it's just off-the-shelf parts - not rocket science."

He feels CAFE's increase in standards is too low: he would set it at 60mpg. Some new cars already exceed that: the new VW Polo Diesel will run at 74mpg.

Two years ago, en route to SEMA, the annual Specialty Equipment Market Association show, he woke up at the hotel to find the Hummer he'd converted surrounded by people. They asked if it had been converted to run on biodiesel and wanted to hear it run.

It was so smooth that they didn't believe it was until they noticed the fan was on. Then they introduced themselves as engineers from GM. "They told us that this couldn't possibly work," he says. Last year, GM produced a line of H2s using the same Duramax engine.

The delivery company UPS recently consulted Goodwin on solutions for its fleet's astronomical costs. He estimates that switching its vehicles to a biofuel/gas-hybrid system could save more than $1 per gallon used, reduce their emissions and provide greater longevity to the engines.

"It's difficult for these huge companies. The technology is there to make cars that have vastly improved consumption figures already, but they're driven by the need to sell all the cars they currently make," Goodwin says.

"If they announced they were bringing out a 100mpg car then no-one would buy the old line, leaving the industry stranded with millions of cars, so they introduce the change slowly. The situation is ripe for a smaller firm to take advantage of."

Goodwin sees three stages to a process of change: converting all autos to diesel which can then run on biofuel, making the step to bio-electric and finally to hydroelectric, meaning cars will run on water.

His approach to being on the cutting edge of fuel-efficient technology is not your average chief executive's.

Nothing is written down and no plans or drawings are made; it's all worked out in his head. He's often to be found on the phone, bouncing around different ideas with whoever is on the other end. These days the person calling is often Neil Young, for long discussions on the constantly changing brief for his 1959 Lincoln Continental.

Encouraged by Young to "go for it", a plan was hatched to convert the car to what he calls a Series Hybrid, using an electric motor driven by a biodiesel-powered turbine. It runs on the same principle as a diesel locomotive: as the car is driven, the turbine generates excess power which is stored in capacitor batteries.

When they're fully charged the turbine cuts out and the batteries kick in. This is capable of cutting fuel consumption and emissions by an estimated 50 per cent. "We're hoping to break the 100mpg barrier," Goodwin says.

Goodwin is talking to a leading carmaker about production of a line of biodiesel cars that his company, Marquee, will oversee the engine work on. His ultimate goal is to build a multipurpose vehicle that can be amphibian, off-road, sports and urban - the car for every situation.