Walmart has a lot of roof space.  A lot.  Walmart had fiscal year 2010 sales of $405 billion.

The retail giant's 2,700 supercenters have a combined roof area that exceeds 500 million square feet -- a blank slate that would make any solar installer or module maker salivate.

Starting with twenty to thirty sites in California and Arizona, SolarCity will install MiaSolé CIGS and First Solar CdTe panels on these flat roofs.  SolarCity will own and maintain the panels.  It's a huge win for SolarCity and perhaps an even bigger win and sign of market credibility for MiaSolé.

Walmart plans for the majority of the rooftop sites to use the new technologies.

When complete, this project is expected to:

  • Supply up to 20 percent to 30 percent of the total energy needs for each location
  • Produce up to 22.5 million kilowatt hours of clean energy per year
  • Add to the 31 current solar installations Walmart has in California and Hawaii

We've covered MiaSolé's recent funding and IPO news here.  Our most recent article addressing First Solar is here.

SolarCity will design, install, own and maintain the new solar power systems on the Walmart rooftops.  SolarCity was selected through an RFP process led by Walmart and the environmental group Environmental Defense Fund (EDF). The goal of the RFP was to identify the most innovative solar technologies that would create benefits on three fronts -- environment, technology, and financial viability.


Updated at 12:30 pm PT

I just spoke with SolarCity's CEO, Lyndon Rive, and he had a few crucial bits to add:

  • The size of the installation is "conservatively 15 megawatts" but, because the design is not finalized, could end up closer to 20 megawatts, which makes it SolarCity's biggest installation.
  • The RFP from Walmart specified thin film in an effort to help get that technology to scale.  SolarCity looked at a number of thin-film vendors and selected MiaSolé after their due-diligence allowed them "to feel comfortable about MiaSolé."
  • Walmart is the most price conscious of companies and "Walmart did not pay more for this," said Rive.  As solar becomes more affordable -- he expects to see Walmart add solar to more and more rooftops.