Published December 7, 2009
Lifelong inventor Johann Hoffmann has devised a way to harness river power to generate electricity without building expensive, environmentally destructive dams
Johann Hoffmann started patenting inventions to protect the environment while still a young boy in his native Austria. His first?
created when he was just 14?was a buoy system to contain oil spills in the ocean, a system that's still being used today. Hoffman's work eventually led him to Brazil, where among other things, he developed a method to clean up mercury contamination from gold mining in the Amazon River.
Now 61, the lifelong inventor is today working not only on keeping waterways clean but also on exploiting their enormous energy. The
goal: to bring clean electricity to areas with little or no access to power. Hoffmann and his partners at CARE Electric Energia, based in Belo Horizonte, Brazil, have designed a turbine system that generates electricity from the natural flow of a river?without needing to build a dam.
The system purports to be more efficient than traditional hydroelectric systems while at the same time being kinder to the environment. "It is not just a technological advance that has been achieved," says Hoffmann, "but a way of providing greater socioeconomic development for poor communities in developing countries and increasing clean energy."
CARE Electric Energia is one of 26 companies named on Dec. 3 by the World Economic Forum as 2010 Tech Pioneers offering new technologies or business models that could advance the global economy and have a positive impact on peoples' lives.
Free Passage for Fish and Boats
The Brazilian company's novel approach to hydroelectric power involves suspending structures in the middle of a flowing river?structures that contain turbine blades, which spin not only from the horizontal flow of the water but also from vertical water pressure that builds up behind the installation. CARE Energy says this allows its turbines to generate power at 90% of their installed capacity, compared with productivity for traditional hydroelectric systems that rarely exceeds 60%.
There are numerous other advantages. Fish and boats can pass by the structures, allowing the river to maintain its ecological balance and its often vital role in commerce and transportation. Unlike a dam, which causes silt and other material to build up behind it, the river continues to flow unimpeded past CARE Energy installations. And except for seasonal variations in the height of the river, the system can operate year-round?unlike dam-based systems, which typically must be throttled for months at a time during dry spells to allow the reservoir to replenish.
The module nature of the turbine system also makes it easy to build in out-of?the-way places: The parts can be manufactured on an assembly line, like a car, and individual sections can be transported to a site, by helicopter if necessary, and assembled at the point of operation. The units are adaptable to almost any river, eliminating long and costly planning, the company says.
No Need for Reservoirs
Two factors make the cost of operation low. First, the turbines are automated by software, allowing them to be remotely controlled by sensors and cameras and supervised via the Internet. Secondly, their design allows them to be placed almost anywhere, so they can be located close to the point of energy consumption.
Of course, one of the greatest advantages of the CARE Electric system is that it doesn't involve constructing a dam, filling a reservoir, and flooding land. That's hugely important, especially in Brazil, where 34,000 square kilometers (8.4 million acres) of land have been flooded to build dams, with more than a million people forced to relocate from their homes. With CARE's technology, people will no longer have to move to make way for dam projects. And it will become economically feasible for the first time to bring electricity to remote areas with little or no access to power?while reducing pollution from diesel fuels.
If the use of CARE's turbines spreads from Brazil to the rest of the world, even developed countries could ramp up production of hydroelectric power, one of the cleanest and most reliable sources of renewable energy on the market today.
Jennifer L. Schenker is the founder and editor of Informilo, a European technology Web site and conference producer, and a former BusinessWeek correspondent in Paris.