Punjab will buy electricity worth Rs.4,000 crore for interrupted supply to farmers for eight hours a day during the ensuing kharif season where more than 28 lakh hectares would be cultivated, the authorities said on Monday.The Punjab State Power Corporation Limited has made multi-dimensional arrangements to meet the enhanced power demand, an official statement said.It said the corporation has signed agreements with various power companies to purchase electricity worth Rs.4,000 crore to provide interrupted supply to farmers for eight hours starting June 10.