More than 800,000 natural gas users in Minnesota will pay more now that CenterPoint Energy has permission for a temporary 4.9% rate increase. State regulators approved the increase this week for CenterPoint, which is pushing to rebuild its aging pipeline network. The company plans to double investment in its distribution system over the next 15 years, and says that it will need more rate hikes than in the past. It has many buried pipelines built from the 1940s through the 1960s. CenterPoint last sought higher Minnesota rates in 2008. It has a request before the Public Utilities Commission for a slightly higher permanent hike.