• The US's big-box retail stores have an opportunity to become more sustainable.
  • 84.4 terawatt-hours of energy can be generated annually from rooftop solar panel placement on the US's big-box stores.
  • With this innovative climate solution, greenhouse gas emissions would be reduced by 52 million metric tons of carbon dioxide annually.

An innovative climate solution would give the US’s big-box retail stores a sustainable makeover.

A new report from Environment America and the Frontier Group calculated that the big, flat and sun-exposed roofs of superstores like Walmart and Ikea would make ideal locations for solar panels. If the 7.2 billion cumulative square feet of big-box roof space in the US were covered in solar panels, that would generate enough electricity to power nearly eight million homes.

“There’s massive potential across the entire country for big-box stores to produce solar,” report author Wade Wilson told The Washington Post. “These are big rooftops that need to be taken advantage of, and we need to start using them.”

The report relied on data from the National Renewable Energy Laboratory to calculate total roof space on the US’s more than 100,000 big-box stores. If all of this potential were used for solar panels, that could generate 84.4 terawatt-hours of energy each year.

What's the World Economic Forum doing about the transition to clean energy?

Moving to clean energy is key to combating climate change, yet in the past five years, the energy transition has stagnated.

Energy consumption and production contribute to two-thirds of global emissions, and 81% of the global energy system is still based on fossil fuels, the same percentage as 30 years ago. Plus, improvements in the energy intensity of the global economy (the amount of energy used per unit of economic activity) are slowing. In 2018 energy intensity improved by 1.2%, the slowest rate since 2010.

Effective policies, private-sector action and public-private cooperation are needed to create a more inclusive, sustainable, affordable and secure global energy system.

Benchmarking progress is essential to a successful transition. The World Economic Forum’s Energy Transition Index, which ranks 115 economies on how well they balance energy security and access with environmental sustainability and affordability, shows that the biggest challenge facing energy transition is the lack of readiness among the world’s largest emitters, including US, China, India and Russia. The 10 countries that score the highest in terms of readiness account for only 2.6% of global annual emissions.

To future-proof the global energy system, the Forum’s Shaping the Future of Energy and Materials Platform is working on initiatives including, Systemic Efficiency, Innovation and Clean Energy and the Global Battery Alliance to encourage and enable innovative energy investments, technologies and solutions.

Additionally, the Mission Possible Platform (MPP) is working to assemble public and private partners to further the industry transition to set heavy industry and mobility sectors on the pathway towards net-zero emissions. MPP is an initiative created by the World Economic Forum and the Energy Transitions Commission.

Is your organisation interested in working with the World Economic Forum? Find out more here.

The study authors wrote that this would have several advantages:

It would reduce greenhouse gas emissions by 52 million metric tons of carbon dioxide a year, which is the same as taking more than 11.3 million cars off the road. It would enable superstores to replace half of their yearly electricity use. It would reduce the energy lost when electricity is sent from one location to another, losses that accounted for 6% of electricity generation in 2020. It would make the electricity grid more resilient.

Some stores and locations have more potential to take advantage of this solution than others. The states that would stand to benefit the most are California, Florida, Texas, Ohio and Illinois. Meanwhile, Walmart has the greatest potential, The Washington Post reported, with nearly 784 million square feet of potential space. Target and Home Depot have the next most potential, Gizmodo reported.

Some of these stores are already taking advantage of the potential of solar energy. Walmart has installed solar panels on its California stores that provide each building with 20-30% of their electricity.

“On-site solar, including rooftop solar, is one of the many tools we use to meet our renewable energy goals,” Walmart spokesperson Mariel Messier said in a statement reported by The Washington Post.

Ikea is another leader with solar panels installed on 90% of its US locations.

However, these and other stores could still do more. The commercial sector generated 12.9 terawatt-hours of solar in 2020, which is about 15% of what the report authors said was possible from big-box stores.