Among them: With the help of a seed grant from IonE's Initiative for Renewable Energy and the Environment, NRRI project engineer Kyle Bartholomew is pilot testing the concept of using taconite tailings to make decorative tiles. The tiles not only look good, they also can function as part of a passive solar energy system, absorbing the sun's energy and radiating it as warmth to provide an efficient source of space heating for homes and businesses.
The process Bartholomew developed starts with a pile of tailings, which look like dusty gray gravel. Bartholomew heats the tailings until they melt, then uses molds to shape the molten material into shiny black tiles. In one test run, he arranged the tiles into a 5-foot by 9-foot array and measured the amount of heat it radiated when struck by the sun's rays. With air temperatures below zero, Bartholomew found the panel could heat its surroundings to 80 degrees.
Used in a trombe wall-type array, Bartholomew says, the transformed taconite panels could add an artistic touch to a room and also help heat it on cold winter days. He's now working with a private-sector partner to move the tailings-to-tiles clean energy invention into commercial production.
Photos courtesy of Kyle Bartholomew