The following video is from Thursday's Digging for Value, in which host Alison Southwick, Motley Fool analyst Michael Olsen and fool.com contributor Tyler Crowe dive deep into the top stories for today's energy sector investors.The twice-weekly show can be viewed on Tuesdays and Thursdays. It can also be found on Twitter, along with our extended coverage of the energy and materials sectors: @TMFEnergy.

In this segment, Tyler discusses how Wal-Mart's (WMT 1.32%) ambitious goals to deliver 7 billion kilowatt-hours of renewable energy to its operations by 2020 plays right into the hands of SolarCity (SCTY.DL). The two companies have a working relationship building over 130 rooftop solar installations on Wal-Mart stores this year, and there is lots of potential to build more of them. While the deals thus far are not earth-shattering for one of the world's largest retailers, the work that SolarCity is doing for Wal-Mart is about 13% of their business this year. Tune into the video below to learn more about this relationship and some other companies that could be looking to ride Wal-Mart's energy goals.