'Green' companies likely to cost you.

FAR TOO MANY alternative energy stocks may be the dot-com bombs of this decade ? sexy today, nowhere tomorrow. With gasoline and crude oil prices hovering at record highs, Wall Street has focused on alternative-energy companies with a dangerous exuberance. Like most fledgling technology companies, many of these green darlings will fizzle or not make a profit for years. Yet there's a compelling reason for investing in this sector as several industry experts foresee petroleum and gas production peaking and emerging economies demanding more energy.