There are no offshore wind turbines generating electricity in U.S. waters yet, but that’s expected to change soon if wind-power advocates and wind developers have their way. The first U.S. offshore wind turbines could be spinning in as little as three to five years if all goes well. The U.S. Interior Department is already conducting environmental impact studies for offshore wind farms at 10 sites in federal waters off the U.S. East Coast, and the agency is expected to finalize its rules for offshore alternative-energy production by the end of the year. For their part, wind-energy companies are especially excited about the offshore potential of the East Coast due to its high electricity prices, high winds, proximity to plenty of energy-hungry population centers, and relatively shallow offshore waters. Yet, despite the momentum and the offshore industry’s promise, the forecast offshore wind-power boom could potentially slow to a crawl if the current federal tax breaks for wind-power projects aren’t renewed before they expire at the end of the year.