Experts are trying to find out if re-purposing former iron mines is a smart investment

Nov 23, 2011 10:55 GMT  ·  By
Abandoned baryte mine shaft in Perthshire, Scotland; an example of small scale open pit mining
   Abandoned baryte mine shaft in Perthshire, Scotland; an example of small scale open pit mining

A group of scientists from the University of Minnesota-Duluth’s Natural Resources Research Institute (NRRI) want to prove that abandoned open pit iron ore mines can harness wind power, supporting a process that will boost the profit margins of the wind industry.

Once put into practice, this theory would provide a win-win situation, both for the considerable land surface facing degradation and for the development of wind power, taking into consideration that such a decision could increase the profit margins of major companies operating on this market, reports CleanTechnica.

This initiative comes as an effective response to Minnesota's capacity of exploiting clean wind power, due to its climate conditions and its geography. The state’s Renewable Portfolio Standard (RPS) highlights that 25% of the entire energy demand has to be satisfied by renewable sources, until 2025.

In order to achieve this ambitious goal, a recent study proves that abandoned open pit mines in the Mesabi Iron Range fulfill all the conditions requested to solve the problem of wind energy storage.

Currently, Minnesota can provide a lot of wind energy, but mostly at night. However, the energy demand is lower at that point in time and the manufacturing companies receive less than what they would get for selling wind power during the day.

Hydroelectric pumped storage systems have been first introduced on the market in the 1890's, in Italy and Switzerland and are able to provide an efficient answer to the present challenges, as they guarantee that 85% of the energy stored can be converted into actual power.

Even so, this alternative is far from being cost-effective, as building such projects requires a significant amount of money.

In order to develop a facility that could provide 1,000-megawatt of power, a company would have to invest up to $2 billion. Therefore, a former pit mine that is already partially or entirely filled with water could represent a convenient option, taking care of a significant percentage of the total costs implied by the operations.

All in all, the builders would still have to take care of the equipment and drilling the tunnels, an action that still involves a significant financial support.

Study shows that former mines have a lot of potential, but a functional 100-megawatt mining-pit system is evaluated at approximately $120 million. While trying to figure out if this path is worth being followed, scientists also take into consideration potential threats and environmental effects.

“It’s very difficult to manage [wind] without some kind of storage capability, and that’s where this type of project fits in[...] the potential is certainly there, based on our study,” states Don Fosnacht, the study’s lead investigator and director of NRRI’s Center for Applied Research and Technology, according to Clean Technica.