Town of Genesee-based Generac will add capacity to one of its Wisconsin plants and fast track opening its new facility in South Carolina following a first quarter where sales for its products increased by 70% year-over-year.The generator manufacturer achieved its highest-ever revenue for a single quarter, which increased from $475.9 million to $807.4 million compared to last year. Residential product sales, including home standby generators, increased by 110% compared to last year.Net income also jumped to $149 million, or $2.33 per share compared to $44 million, or 68 cents per share for the same quarter in 2020.Generac’s first-quarter results benefited from the major power outages in Texas caused by winter storms along with measures the company took to expand production of home standby generators. With broad-based growth across Generac’s entire business, the company adjusted its guidance to about 40% to 45% growth compared to a previously reported range of 25% to 30%.The manufacturer already doubled capacity at Wisconsin plants compared to levels from 12 to 18 months ago, said president and CEO Aaron Jagdfeld. Now Generac plans to double capacity for standby residential generators by adding a permanent line at its Jefferson, Wisconsin plant and opening its new facility in Trenton, South Carolina earlier than expected, Jagdfeld recently told analysts.“That second line we’re adding in Wisconsin, the quicker ramp of Trenton and then bringing on more equipment early next year is what gets us to doubling where we’re at today,” Jagdfeld said. “So, if we do get an active hurricane season, we feel like we would be ready for that.”Generac Power Systems Inc. recently acquired a 421,000 square-foot manufacturing and distribution facility in Trenton, South Carolina. The facility will support increased demand for standby generators and associated energy technologies while serving as a distribution center to consumers in southeastern United States.Generac expects the new facility and added capacity at its Jefferson plant to come online by the third quarter of 2021, Jagdfeld said.