From wind turbines to fuel cells... clean-tech businesses are ushering in a green-energy revolution that may help lift Britain out of recession. The government hopes thousands of jobs will be created in low-carbon industries, but seeking investment is a challenge as funding tightens. Here, we profile seven innovative companies flourishing despite the downturn

Quiet Revolution
Industry: wind power
Turnover: £2m
Amount invested: around £7m
Principal investors: RWE, Hazel Capital, Robert Webb and Ben Guest

The problem with putting wind-powered turbines in urban areas is the quality of the wind. Buildings of various heights produce a gusty, turbulent airflow, which is constantly changing direction. There is another barrier: turbines are noisy once they get going, which isn't a problem in the Scottish Highlands or out at sea, but an anti-social menace in a densely populated city.

Quiet Revolution claims to have the answer. "If you have the space, and you can get planning permission, go and get the biggest turbine you can find," says the company's commercial director, Julia Groves. "Where we come in is where big wind can't happen, or the nature of the wind is very different."

Conventional, three-blade, horizontal-axis wind turbines (HAWT) must rotate to pick up the prevailing wind, but Quiet Revolution turbines can gather wind from all directions without tracking. Groves says they are 20-40 per cent more efficient in turbulent winds than HAWT models. They also "whisper" rather than whine. "The curve and tapering of the blade helps the wind to be shared across the turbine more evenly," she says. One of the company's 75 UK installations is on top of the science block at King's College School in Wimbledon. "It is inaudible from below," says Groves.

Intelligent Energy
Industry: fuel cells
Turnover: undisclosed
Amount invested: £59.3m
Principal investors: Credit Suisse Securities, Black River Commodity Clean Energy Investment Fund, Black River Global Equity Fund, Meditor Capital Management and Evolution Placements Corporation

Intelligent Energy was spun out from Loughborough University in 1988, but only recently has its fuel-cell technology been considered ready for commercial use.

Originally a partnership between Loughborough's chemistry and automotive departments, Intelligent Energy's chief innovation has been to make the hydrogen fuel cell scalable and affordable. Chief executive Henri Winand says he's had to battle scepticism over the technology's availability. "People will have you think it's something for tomorrow. But it's working today."

In February last year, Intelligent Energy teamed up with Boeing to launch the inaugural flight of the world's first manned fuel cell-powered aircraft. The company has a deal with Peugeot to power its H2Origin delivery van. And it also supplies the fuel cell for Suzuki's much-anticipated Crosscage motorbike, although it's still not clear when the bike will go into production.

Winand says he is open to partnerships with other technology providers. Fuel cells, for example, can power a car over long distances, while batteries are useful for short-distance acceleration, making fuel-cell hybrids viable. "The difference in the debate since I joined as CEO in 2006 is that the discourse between myself and competitors is [no longer] about the technology and whether it works. It's about my assets plus your assets: how can we tackle a commercial market? That is far more exciting than 'my technology is better than yours'."

E-stack
Industry: ventilation
Turnover: undisclosed
Amount invested: £2.5m (to the research programme)
Principal investor: BP

E-stack is a good example of how industry-funded research at universities can spin out into a profitable business. In simple terms, the E-stack low-energy ventilation system has the potential to cut the fuel consumption for naturally ventilated buildings by half.

The business was spun out of a research programme—funded by BP in 2000 to the tune of £2.5m-between the University of Cambridge and MIT (Massachusetts Institute of Technology), which had as its one big question: how do you create a low-energy building? The final answer: a ventilation system that overcomes the two big challenges for natural ventilation—draughts in winter and overheating in summer—by recycling heat generated by people, IT equipment and lighting.

Shaun Fitzgerald is the company's managing director and an original research team member. He and Professor Andy Woods filed a patent for the idea and, "after going through some hoops", a deal was negotiated for exclusive rights to the technology for themselves and BP, while the university became a shareholder. That was in 2006. They now have 15 installations across the UK.

Given that buildings account for 40 to 50 per cent of all energy consumption in the developed world, Fitzgerald says it's obvious why BP are still involved. "Historically, they've been an energy provider, but in 50 years' time, will we need energy provided in the same form? By being involved with a company that makes it its business to understand the way energy is used and do something about it, they're continually informed and educated."

Martek Marine
Industry: marine
Turnover: £2.5m (for MariNox)
Amount invested: £250,000 (in MariNox)
Principal investors: Paul Luen, Mike Pringle and Steve Coulson

Martek Marine, a maker of environmental monitoring systems for the global shipping industry, is making a splash in a sector that has seen little "green" legislation in the past. "The engine of a large ship uses the same amount of fuel as a small power station-hundreds of tonnes a day," says founder and managing director Paul Luen. "Ships were burning dirty fuel and there was no restriction really on what they were emitting."

But this is changing as the industry recognises that ships have to become greener, following tireless lobbying by pressure groups such as Friends of the Earth and Greenpeace.

Identifying an increasing need for responsible operators to be able to accurately determine CO2 usage, Martek created MariNox, an engine emissions monitoring system. "It was clear there would be commercial drivers in the industry that would create the need for these systems on board ships," says Luen.

By measuring emissions as well as temperature, pressure, humidity and fuel flow, MariNox allows operators to tune engines in a different way to cut fuel consumption. Trials have shown an average fuel saving of 2.45 per cent. "That may not sound an awful lot, but for a big ship it can be the equivalent of the CO2 emissions of 3,200 cars," explains Luen. "So while it's only two to three per cent in real terms it's an awful lot of CO2 that's being saved."

Origo Industries
Industry: carbon capture
Turnover: £2.4m (from carbon trading)
Amount invested: undisclosed
Principal investor: Ian Houston

Origo makes a carbon-capture device called the Ecobox. Founder Ian Houston first tested the Ecobox last year on his Mitsubishi Shogun Sport. The equipment, which is fixed to the exhaust, reduced the vehicle's emissions from 275g per kilometre to less than 100g. "It went from being in the highest road-tax band to no road tax," he explains. The captured carbon can be converted back into fuel. Houston says he receives "880,000 pre-estimated orders for Ecobox each month", mostly from car dealerships, and he is in talks with vehicle manufacturers. Fitting the device to one million British cars would remove around 8,000 tonnes of CO2 from the atmosphere each day, the equivalent of "disconnecting an entire power station from the national grid".

The Ecobox has other uses. Fitted to the air conditioning unit of a building, it can capture people's carbon emissions, too. Origo has signed a partnership with John Lennon airport in Liverpool to trial CO2 capture from inside the terminal building. The captured carbon is recycled through a photo-bioreactor to produce an algae-based biofuel, which can be used to power the airport's ground vehicles and generate electricity. "We could capture up to 10 tonnes just from the passengers walking to get their flight," says Houston. "If you can take that CO2 and convert it back to fuel, you're reducing the carbon footprint of that airport and the passenger."

Green Energy UK
Industry: energy provider
Turnover: £5m
Amount invested: £50,000
Principal investor: Doug Stewart

From a car dealer to a provider of environmentally friendly electricity is a big leap. But Doug Stewart, founder of Green Energy UK, says he saw an opportunity to ease his conscience and create a commercially viable venture. "If you can make money doing good then you shouldn't be uncomfortable with that as a business model," he explains.

The company buys its electricity—100 per cent renewable and 100 per cent green—from a wide range of sources. Renewable means wind, sun and water. Green energy is low carbon and low impact, bought from combined heat and power units that recycle materials such as pig waste or vegetable oil into fuel. "We're not wedded to wind," says Stewart. "What we like is predictable energy. We've always supported small-scale and emerging technologies. We set out to try to convert people from brown [fossil fuel/nuclear] to green energy."

Stewart says his customer base ranges from homes using as little as £50 worth of fuel a year to big businesses seeking to mitigate their environment impact by using a green tariff. What unites them, he says, is their desire to "take ethical stewardship" of the planet. "We deal with nice people at both ends of the spectrum, who collectively want to make a difference," he says.

Fittingly, he intends to grow the business organically, without seeking further investment.

Flybrid Systems
Industry: kinetic energy recovery systems
Turnover: £1m
Amount invested: £350,000
Principal investors: Jon Hilton and Doug Cross

In 2007 Flybrid developed a high-speed Flywheel-based energy storage and recovery system in response to a change of technical regulations for Formula One that allowed the use of kinetic energy recovery systems from the first race of 2009.

In a nutshell, the Flywheel captures and stores energy used by a vehicle as it breaks and passes the energy back to the wheel to help it accelerate again. "It can return about 70 per cent of the energy we capture—so for a racing car, this is used to make it go faster," explains managing partner Jon Hilton.

Although Flywheel-based hybrid systems are nothing new, part of Flybrid's core technology is how it has made the system run so fast and therefore can make it so small. Hilton claims that it's also technically better and cheaper to manufacture than battery electric systems.

Flybrid is now working more and more with road vehicle manufacturers. "On road cars we are using the technology to get the car back up to speed without using the engine—therefore saving a lot of fuel consumption and CO2 emissions," says Hilton. He adds: "In real world terms the CO2 saving is about 30-35 per cent with pretty much any car and any journey."

Hilton says they'll be supplying road cars in volume with the technology that we'll be able to buy by 2013. He believes the potential market is huge: that more than half, and maybe as much as 80 per cent of all new cars will have some sort of kinetic energy recovery system (known as KERS in the industry) fitted by 2020. He plans to capture as large a part of the market as possible.

"We're mad about going as fast as we possibly can to develop the technology and stake out a claim to as much of it [the market] as possible so that when the technology matures we're left holding a decent chunk of it," he says.