Dr. Edmonds says the advantage of his balloon engine lies in geographical areas that do not have very much wind, but has abundant amounts of sunlight.
In the New Scientist article “Hot-Air Balloons Power Up,” Edmonds states, “It is like a huge two-stroke engine, with a capacity of 45 million litres, a stroke of 3 kilometres, and a frequency of one revolution per hour.” [January 17-23, 2009, page 19]
To see a diagram of the cycle of the balloon engine, please go to the January 26, 2009 Inhabitat.com’s article “Hot Air Balloons Could Power Your House.”
For the complete paper describing Dr. Edmonds invention in the journal Renewable Energy, go to Solartran/Renewable Energy (pdf file).
For a history of hot air balloons, go to "The History of Hot Air Balloons."