A century ago, Consumers Energy pioneered renewable energy in Michigan with a string of hydroelectric plants along the state's rivers, and many of those plants still operate today alongside a newer generation of renewable energy sources led primarily by wind power, with plans to develop biomass, landfill gas, and solar energy as well. Electric power was pioneered in Michigan along its rivers, and Consumers Energy continues to operate 13 hydroelectric plants on five waterways. Built between 1906 and 1935, the plants have a combined generating capacity of about 130 megawatts, enough to serve more than 55,000 people. Near these hydro plants are campgrounds, boat launches, picnic spots, and other recreational facilities that support canoeing, fishing, bird watching, and exploration of nearby nature trails. At Mio Dam, the powerhouse was built beside the original river channel while the river was diverted so the embankments could be completed, and a left-side trestle used to transport materials became a key structural component of the embankment. Mio Dam was designed with a conduit, or under-sluice, spillway patented by engineer William W. Tefft and built within and under the powerhouse rather than beside it, unlike earlier dams on the Au Sable River such as Five Channels Dam. Because transportation in northern Michigan was still very limited during construction and the railroad never reached Mio, turbines were shipped by the Robinson Lumber Company narrow gauge rail from South Branch to the end of the line southwest of Mio and then hauled by horse-drawn sleigh to the dam site. Shortly after construction, Mio Dam used two Francis vertical turbines and two Allis-Chalmers generators.