Repowering Old Mines with New Energies in the Southwestern United States

A common challenge that mining companies face with legacy sites is what to do with the disturbed land once the resource has been exhausted or extraction is no longer profitable. After closure, mines need to undergo a long process of reclamation. At this stage, the reputation of mining companies—their social license to operate—becomes tied to the fate of the townships that used to provide the labor force for the mines, and that are now oftentimes searching for a new identity. But, mining communities in the Southwestern United States have another resource that can be mined: the sun. These communities, at risk of disappearing after mining operations have ended, can be greatly aided by renewable energy installations on former mine sites.

Over the last several years, Rocky Mountain Institute’s (RMI’s) Sunshine for Mines Initiative has embarked on several key partnerships with mining companies on the redevelopment of closed mine sites in the Southwest. Recently, our team was in Globe, Arizona with global resources company BHP to discuss economic development as part of an engagement organized by the nonprofit Rural Community Assistance Corporation, a group that provides training, technical and financial resources, and advocacy so rural communities can achieve their goals. Given that Arizona’s average irradiance of over 6 kWh/m2/day represents hands-down the best solar resource in the United States, Globe seems to be already ahead of the curve. The community understands that energy, more than ore, may hold the key to future economic growth.

Partnering for Potential

Across the country, there are swaths of mine lands, primarily brownfield sites that have been closed for one reason or another, that are now prime locations for renewable energy. That’s where Sunshine for Mines comes in. Our goal is to help the mining industry shift from a paradigm of extraction to one of stewardship, especially when it comes to energy and emissions. Sunshine for Mines has been very active in the US Southwest, collaborating with some of the largest players, including BHP and Freeport McMoRan, to figure out their ongoing role in the ever-changing energy landscape of a region traditionally devoted to mining. Clean energy and economic development are not mutually exclusive and can both thrive in towns like Globe. Thanks to the drop in costs of clean energy technologies, it is absolutely possible for legacy mining communities to benefit from the potential of renewable energy.

For example, elsewhere in the Southwest, in the state of Nevada, RMI has been collaborating with The Nature Conservancy to identify 2.8 million acres of brownfield sites that could be utilized for renewable energy. Even considering solar photovoltaics (PV) alone, these sites have the potential to provide 2,388 percent of Nevada’s current renewable portfolio standard (RPS). This is not a typo: that’s more than 20 times the capacity required for the state to meet the RPS. That’s a lot of clean and renewable energy available to be harnessed.

Renewables on Brownfields:  An obvious win-win, with some short-term challenges

Despite making economic sense, renewable energy installations are not yet an obvious choice for mining sites. Nationwide, examples are few and far between. While no significant on-site capacity exists on an active mine, closed sites have had a little more luck. The 1 MW concentrated solar plant built by Chevron in 2011 on its Questa mine site in New Mexico is now selling clean energy to a local cooperative. More dramatically, Asarco has a 35 MW clean energy facility in Arizona, in the territory of Tucson Electric Power. But further north, in the region of Globe, it has been more difficult for a project on mine land to come to fruition.

The main limiting factor across the Southwest seems to be that, despite the dramatic decrease in the cost of technology, which, in the case of solar PV, has dropped by 90 percent in recent years, creative and community-driven solutions are lacking. In many cases, local regulation does not help identify solutions. When initiation of a project is not driven by the local utility, the cookie-cutter solution for developing large-scale renewable capacity in this corner of the country is to find a large buyer for the electricity through a power purchase agreement (PPA). But it has been difficult to find or attract industrial demand in places like Globe.

Energy reliability is perhaps an even more pressing concern than clean energy in rural communities. Many mining townships are connected to the grid, but they sit at the edge of it. In Globe, it only takes a chat with some locals to hear stories of frequent blackouts.

A local, creative solution fostered by a large player might help. There is no one-size-fits-all answer, but rather an array of configurations: a large-scale solar and battery plant on a closed brownfield can power one or more large local energy consumers. The same large plant—which, in the case of Globe, might be owned by a mining company—can serve as the “anchor supplier” to a community solar effort, where a combination of large-scale off-site generation and residential rooftop solar would enable local residents and businesses to access cheaper and more reliable renewable power. At the very edge of a utility territory, a local microgrid can add huge value to both the community and the utility by adding resiliency. The formation of a municipal or cooperative utility might be part of a solution, too.

As the proportion of renewable energy that serves a territory gets larger, industrial consumers interested in this type of offtake would be incentivized to move to the region. On top of attempts to attract the new Amazon headquarters—bids were submitted for several locations near Globe, including Mesa, and Tempe, Arizona—a number of other data center companies have expressed interest in the region in the recent past. These types of energy consumers are typically sensitive to using a clean electricity mix. Electronics manufacturing, too, could exploit the semiconductors expertise that is present in the area.

Good for the Globe and Good for Globe

Brownfield development has the potential to change the face of local economic and environmental ecosystems without touching a single acre of pristine land, and it can chart a path of sustainable growth. This is something that can benefit both the upper-and the lower-case Globe. While the effects of climate change span the globe, mining communities like Globe are at risk of disappearing.

Mines in the Southwest produced a significant portion of the copper that was key to building the electricity grids in the United States in the 20th century, and many of the electronic appliances that drive today’s economy. For these mining companies, their social privilege to operate is now tied to the fate of the towns that used to provide the labor force for the mines and are now searching for a new identity. Maybe renewable energy is the key to once again getting the world coming to Globe —not in search of silver or copper, but rather to harness the resource that shines, strong and stable, over each square foot of this beautiful region.