A Marshalltown-based R-E-C has installed a new-fangled tubing system that will filter sunlight to unlit areas of their new headquarters. Brian Heithoff , general manager of Consumers Energy in Marshalltown, says it’s called “solar tube” technology.Heithoff says the tubes connect to a hole in the roof, and the tubes transmit the sunlight throughout the building. The system was financed, in part, by a 120-thousand dollar federal grant. The R-E-C intends to install a couple of wind turbines to provide electricity for their new corporate headquarters, which they bought from a transportation company. Heithoff says since the R-E-C is an energy company, one of the first things they noticed was the building wasn’t well-insulated. So, they used isonene insulation which is sprayed on rather than traditional fiberglass insulation. Heithoff says they hope to have the building ready for occupation by the end of March.