(Reuters) - U.S. utility companies Duke Energy Corp and Xcel Energy Inc XEL.O said natural gas will remain part of their power mix for years to come to help keep electric grids reliable and power affordable as they transition to cleaner forms of energy. Speaking at CERAWeek by IHS Markit, Xcel Chief Executive Benjamin Fowke said “We need to keep some gas to keep our system reliable. We can’t sacrifice affordability and reliability.” Fowke said wind power can play a very big role in the energy mix, noting “this year wind will be largest source of power on our grid and it’s the cheapest form of energy we have on our system.” Xcel has a goal to reduce carbon emissions by 80% compared with 2005 levels by 2030 and reach net-zero emissions by 2050. “To get to 80% is not an easy thing,” Fowke said, noting the company will continue to move away from coal, preserve its existing nuclear fleet and have about 65%-70% of energy from renewables by 2030. To reach the last 20%, however, Fowke said “I want to get to 100% carbon free and I think 2050 is the right timeframe, we need new technologies” like next-generation nuclear, more battery storage and carbon capture and storage. Duke CEO Lynn Good said on the same CERAWeek panel that “We share a common goal of reducing carbon emissions but we need to do it in a reliable way.” “Natural gas plays an import role in balancing the system,” Good said, noting “gas will continue playing a role into the future.” She said 50% of generation in the Carolinas comes from carbon-free sources like nuclear and solar. North Carolina was third in the nation with installed solar. Like Xcel, Duke is striving to reach net-zero carbon emissions by 2050. Separately, Good said Duke sees opportunities to reduce its real estate costs as more people work from home during the coronavirus pandemic.