DUNDALK, Ireland: When the fearsome Cuchulainn was transformed by the rage of battle into a Celtic Incredible Hulk, according to Irish mythology, the warrior's intensity melted snow for 30 feet around him. That was an impressive generation of alternative energy from this Achilles-like hero so closely associated with Dundalk, but this town on Ireland's east coast is turning to less ephemeral kinds of power as it tests technologies to reduce the country's thirst for fossil fuels. The goal is innovation on a local scale, developing clean energy sources and reducing energy demand in a 4-square-kilometer, or 1.5-square-mile, site called a Sustainable Energy Zone. The project is part of a European Union program to encourage pilot projects that can be scaled up to regional or national levels. Dundalk is working with two other towns, in Austria and Switzerland, on a total budget of about