Robert Congel, a commercial real-estate developer who lives in upstate New York, has a plan to 'change the world.' Convinced that it will 'produce more benefit for humanity than any one thing that private enterprise has ever done,' he is raising $20 billion to make it happen. That' s 12 times the yearly budget of the United Nations and more than 25 times Congel' s own net worth. What Congel has in mind is an outsize and extremely unusual mega-mall. Destiny U.S.A., the retail-and entertainment complex he is building in upstate New York, aspires to be not only the biggest man-made structure on the planet but also the most environmentally friendly. Equal parts Disney World, Las Vegas, Bell Laboratories and Mall of America -- with a splash of Walden Pond -- the 'retail city' will include the usual shops and restaurants as well as an extensive research facility for testing advanced technologies and a 200-acre recreational biosphere complete with spring-like temperatures and an artificial river for kayaking. After a false start in 2002, countless changes of plan and a storm of local opposition, Congel is finally breaking ground again, with a projected completion date of 2009. Later this month, bulldozers powered by biodiesel are scheduled to begin leveling the site, a rehabilitated brownfield in Syracuse, Congel' s hometown. Whether Congel' s firm, the Pyramid Companies, can maintain the cash flow and political support needed to complete the project is a subject of much local debate. Also disputed are Congel' s goals of creating 200,000 jobs regionally and making Destiny nothing less than 'the No. l tourist destination in America.' More mind-boggling than the sheer scope of Destiny is its agenda. Congel emphasizes that renewable energy alone will power the mall, with its 1,000 shops and restaurants, 80,000 hotel rooms, 40,000-seat arena and Broadway-style. theaters. As a result, Congel says, Destiny will jump-start renewable-energy markets nationwide with its investments in solar, ,,wind, fuel cells and other alternative-energy sources. But if Congel does manage to erect his El Dorado, will it really help cure our country' s addiction to scarce and highly polluting fossil fuel? Or will it just be a cleverly marketed boondoggle that may create more environmental problems than it solves? All by itself, the mall would boost America' s solar-electric power capacity by nearly 10 percent. 'On every level, this project astounds,' Senator HIillary Clinton said in April, claiming that the mall could make the area a hub for clean technologies and deliver a shot of adrenaline to upstate New York' s ailing economy. To help foot the bill for Congel's project, Clinton and other politicians successfully persuaded Congress to provide financial incentives for mega-scale green development projects. (Destiny, of course, will face little competition to reap hose benefits.) The mall is astounding because ______.