Mayor Jerry Abramson is inviting business owners and building managers to take part in the second annual Louisville Kilowatt Crackdown. It's a yearlong contest in which the owners and managers report their monthly energy usage and come up with ways to make the structures more efficient.Abramson says the first Kilowatt Crackdown, which continues through the end of the year, drew many more participants than expected."We had hoped initially to get 15 buildings signed up for the contest. We must have struck a nerve because i'm proud to announce that in the first year of our Kilowatt Crackdown, 240 building's participated," Abramson said.The EPA's ENERGY STAR program says commerical buildings are responsible for nearly 50-percent of national greenhouse gas emissions.Abramson says there's no cost to enter the Kilowatt Crackdown contest.