Carports provide shade for cars and energy for buildings in the area. Image: SunPower.

2015 was another great year for U.S. companies installing solar energy, and according to the Solar Means Business 2015 report by the Solar Energy Industries Association there are now over 907 MW of solar in 1,686 corporate installations around the country. That's up 59% from a year ago, and growth should accelerate in 2016 as the investment tax credit winds down from 30% to 10% for installers.

Here are the corporate players that love solar energy.

The leaders in corporate solar
Walmart (NYSE:WMT) has long been ahead of the curve on solar energy, partnering with SolarCity (NASDAQ:SCTY.DL) to expand its presence even further in 2015 to 348 locations. That's impressive, but there's still a lot of upside with 4,835 locations in the U.S. and about 11,000 worldwide.

Target (NYSE:TGT) experienced the most growth this year, driven by a partnership with SunPower (NASDAQ:SPWR) to install systems. The company hopes to have rooftop solar at 500 locations by 2020. 


Installations in 2014 

Installations in 2015 



105.1 MW

142.0 MW

+36.9 MW


84.9 MW 

97.5 MW

+12.6 MW


14.9 MW

71.9 MW

+57.0 MW


40.7 MW

60.7 MW

+20.0 MW


48.1 MW

50.7 MW

+2.6 MW

Source: Solar Means Business 2015 and 2014, SEIA.

Apple is the other very high profile solar installer, although it's not putting it on rooftops like most retailers are. Instead, Apple is building small installations of around 20 MW near data centers in North Carolina and Nevada with SunPower. And it's taking that love of solar international as well.

SolarCity is hoping the ZS Peak design improves its position in commercial solar. Image: SolarCity.

U.S. companies are taking solar international
The Solar Means Business 2015 report tracks U.S. commercial solar users, but it doesn't track international installations -- and those are starting to grow for these same companies. Apple, for example, already has 40 MW of SunPower projects producing enough power to cover its offices and retail space in China. And it recently announced a deal to build 170 MW of solar in Inner Mongolia, with SunPower and Apple each owning an equity stake in the project. 

In total, Apple is hoping to get its supply chain partners involved in building solar, meaning 2 GW of solar will eventually be built to offset the company's energy footprint in China.

Solar is a corporate no-brainer
Solar energy isn't just clean energy companies can use to project a green image; it can save businesses 20% or more on energy bills. Over the life of a solar system the savings can add up to hundreds of thousands of dollars for a single building. The one-two punch makes solar a no-brainer for companies in the U.S., and you can see that some of the biggest, most profitable companies in the country are installing solar at a very rapid rate.

As costs fall and new technologies like energy management and energy storage become more competitive, I think we'll see energy consumption shift rapidly in Corporate America, with solar playing a central roll. The momentum taking solar this far isn't going to stop anytime soon, and that's good for both solar companies and their corporate customers alike.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.