Wal-Mart today announced a major commitment to solar power. This is part of the retail giant’s ambitious, ongoing drive towards sustainability, about which I’ve written a lot. Long term, Wal-Mart wants to get 100% of its energy from renewable sources–as we all must if we intend to live in a truly sustainable world.

This week’s CNNMoney.com column looks at the Wal-Mart deal. A couple of noteworthy elements: Wal-Mart will never own the solar panels on its roofs, instead entering into long-term contracts will its solar suppliers, which finance, own and maintain the systems. Also: This will be a money-saver for WMT from day one, in part because of generous subsidies for solar power.

Here’s how the column begins:

Wal-Mart is looking to the sun for power – and to save a few pennies on its electric bills.

The giant retailer says it will install solar rooftop panels at 22 facilities in California and Hawaii that will provide as much as 20 megawatts of electricity, for prices less than it currently pays local utilities.

Wal-Mart will purchase the electricity from BP Solar, a unit of global energy giant BP based in Frederick, MD, from SunEdison, a privately held firm headquartered in Beltsville, MD, and from SunPower Corp. of San Jose, which provides solar power to Wal-Mart’s experimental store in Colorado.

You can read the rest here.