Harvesting tornadoes as power plants; renewable wind vortex energy
Rhett A. Butler, mongabay.com
October 9, 2005

Engineers are working to use artificial tornadoes as a renewable energy source according to an article in last week's issue of The Economist.

Storms release a tremendous amount of energy. Hurricane Katrina, a category 4 hurricane, released enough energy to supply the world's power needs for a year, while the typical tornado produces as much power as a large power station.

Engineers are looking a ways to harness this energy for human use. Louis Michaud, a Canadian engineer, has developed the "atmospheric vortex engine" -- a device that he believes can capture and control energy stored in artificial tornadoes.

As described in The Economist, his system "works on a similar principle to a solar chimney, which consists of a tall, hollow cylinder surrounded by a large greenhouse. The sun heats the air in the greenhouse, and the hot air rises. But its only escape route is via the chimney. A turbine at the base of the chimney generates electricity as the air rushes by... His scheme replaces the chimney with a tornado-like vortex of spinning air, which could extend several kilometres into the atmosphere."

Michaud's "vortex would be produced inside a large cylindrical wall, 200 metres in diameter and 100 metres tall. Warm air at ground level enters via tangential inlets around the base of the wall. Steam is also injected to get the vortex started. Once established, the heat content of the air at ground level is enough to keep the vortex going. As the air rises, it expands and cools, and water vapour condenses, releasing even more heat," much like how a hurricane frees energy by drawing warm humid air from its base (usually tropical sea water) and then releasing cold, wet air 7 miles (12 kilometers) up in the troposphere.

"The intensity of the vortex would be controlled by closing the inlets around the base, or by opening another set of inlets to inject air in the opposite direction and so slow the vortex's rotation. And, of course, there would be a set of turbines at the base of the vortex that would allow its energy to be harnessed as air rushed through the inlets. Mr Michaud estimates that an atmospheric vortex engine with a diameter of 200 metres would produce around 200 megawatts of power."

History of solar chimney designs

A solar chimney is a device for harnessing solar energy by the convection of heated air. First officially described in 1931 by a German author, Hanns Günther, the first functional model solar chimney power station was built in 1982 in Manzaranes, Spain. Funded by the German Government, the power plant operated for eight years. The chimney had a diameter of 10 metres and a height of 195 metres, with a collection area (greenhouse) of 46,000 m² (about 11 acres) obtaining a maximum power output of about 50 kW.

source: Wikipedia
Mr Michaud is not the only person working on harnessing energy using a solar chimney concept. EnviroMission, a public company in Australia, is building a 50MW power station on the Sunraysia site in Buronga, New South Wales, that is based on a solar chimney concept. The technology, which EnviroMission calls a Solar Tower power station, uses the sun's heat to warm a large body of air which then rises through a vertical wind tunnel causing large turbines to spin and generate electricity. The amount of energy generated is directly proportional to the height of the tower. The proposed Buronga tower will be over 3300 feet (1000 meters) tall.

EnviroMission says a single 200MW Solar Tower power station will provide enough electricity to power around 200,000 households, but at a savings of more than 900,000 tons of carbon dioxide, an important greenhouse gas. Such a wind-based power scheme could play an important part in supplying energy in a future where carbon-based fossils fuels are expensive and heavily regulated due to their impact on the environment and global climate.

Related energy articles

Related articles

High oil prices make Asia pursue green energy September 9, 2005
For energy-hungry Asian governments, the answer could literally be blowing in the wind. Across the region, renewable energy such as solar, wind and geothermal power is gaining ever greater credence as a way to curb the region's appetite for oil and cut runaway import bills. With oil prices near $70, and expected by many analysts to stay over $50 through the end of 2006, governments believe alternative energy will help keep their economies growing.

Cockroaches and rats used as batteries? August 24, 2005
An article in today's Manilla Times highlights some local research into using common household pests as energy sources. A group of scientists from Feati University recently devised a biological fuel cell that uses the enzyme Nicotinamide Adenine Dinucleotide (NAD) to directly convert biochemical energy into electricity. Their research raises the possibility that household pests like mosquitoes, rats, cockroaches and flies could be used as biofuel sources. Cockroaches generated the highest amperage, according to the article.

Australian inventor believes he can turn sewage into energy source August 23, 2005
An Australian inventor believes he can turn human waste into an energy source. Cy d'Oliveira, an inventor from Queensland, Australia, has devised a system that purportedly converts sewage and paper pulp into methane and other raw energy sources. He calls the system the d'Oliveira Natural Gas Refinery (dNGR) and claims the technology could produce up to 4.71 Kwh (17,000MJ) of electricity per 1Kg of sewerage sludge. Mr. d'Oliveira views his dNGR as a potential way for reducing greenhouse gas emissions produced by the combustion of fossil fuels.

Poor need renewable energy sources says Annan August 23, 2005
In a new report, United Nations Secretary-General Kofi Annan says energy poverty is seriously impeding socio-economic development in the world's poorest countries. Noting that in the developing countries some 1.6 billion people still lack access to electricity and about 2.4 billion continue to rely on traditional biomass like fuelwood for cooking and heating, Annan calls for intensified efforts to promote renewable energy sources for the poor.

Renewable energy in China, a strategic future? August 2, 2005
With a host of environmental and domestic social concerns -- and potential future international conflict -- China could be well suited to pursue renewable energy sources. China's failed bid for American petroleum firm Unocal may prompt it to further focus on its development of alternative energy sources. The country has recently passed a renewable energy law that requires power operators to buy electricity from alternative energy producers and the government has increased spending for research on wind, solar, biofuel, and tidal technologies.

China to add wind power capacity August 15, 2005
In recent years China has significantly expanded its interests in renewable energy sources including wind, solar, biofuels, tidal, and small hydroelectric dams. Below is an article from the Associated Press on a planned expansion of the country's wind power capacity.

Cow manure + sunlight + metal ore = hydrogen fuel? A safe way for storing hydrogen August 11, 2005
Researchers led by Michael Epstein at the Weizmann Institute of Science in Israel think they may have an energy efficient way of collecting solar energy to generate hydrogen, a key input for green energy technologies like fuel cells. Currently, most hydrogen is produced by processes that require the combustion of fossil fuels which produce polluting greenhouse gases. Further, to date, finding safe and cost-effective means for the storage and transportation of hydrogen gas have proved elusive. Epstein's process has the potential to address a number of these issues by "creating an easily storable intermediate energy source form from metal ore, such as zinc oxide," according to a release from the Weizmann Institute of Science."

China announces wave power station technology advancements July 27, 2005
China announced that it has developed typhoon-resistant technologies for the world's first experimental wave power station. The announcement comes two months after a Norwegian firm signed an agreement to construct a commercial wave farm to harvest electricity from sea swells off the coast of Scottland.

China's Imminent Water Crisis May 30, 2005
China has long suffered from alternating periods of severe flooding and drought. Combined with high pollution levels and a history of heedless and haphazard policies, the country is witnessing a precipitous drop in this most essential supply. High ranking officials and international agencies alike are deeply concerned about the situation and with good reason.

The article used quotes and information from The Economist: "Alternative energy -- The power of spin," Sep 29th 2005.

Rhett A. Butler, mongabay.com (October 09, 2005).

Harvesting tornados as power plants; renewable wind vortex energy.