Welcome to the 30th installment of The Wal-Mart Weekly, a column dedicated to bringing you insight, wit, facts, results, opinions and just a bit of everything else when it comes down to a very hot topic these days: Wal-Mart.

Last week, I brought you a two part series on what Wal-Mart Stores, Inc. (NYSE: WMT) needs to focus on in order to restore the consistent growth it has enjoyed for well over a decade now. Here is part 1 and part 2.

This week, I'll be looking at a burgeoning opportunity with the retailer that is getting some pretty decent traction in the press, but is being lost on the Wal-Mart customer. That is, the retailer's growth in the last 18 months as a "green-friendly" corporate citizen, which has the chance to make a significant impact on the global environment. As usual, it seems this message is not being trumpeted from every voice within Wal-Mart to every Wal-Mart customer. It should be, though.

Wal-Mart's environmental sustainability efforts

Since 2006, Wal-Mart's initiatives in the environmental arena have generated a wealth of new programs. The retailer has required vendors to curb back on packaging sizes (or risk losing business), has implemented energy conservation strategies in many store locations, has been a huge proponent of selling compact fluorescent light bulbs (CFLs) in stores and has begun initiatives to make its nationwide truck fleet conserve energy through several methods.

Add to that this week's announcement that the world's largest retailer would soon only stock concentrated laundry detergent, and it's easy to see that Wal-Mart is slowly but surely making the move to offering "greener" products to customers. So, with energy conservation, waste reduction, pollution reduction and product categorization, the retailer is attacking overuse and overconsumption head-on. Now, Wal-Mart is not the only retailer involved with these actions -- many smart and forward-looking companies apply some or all of these principles as well. But, in Wal-Mart's case, the retailer has the reach and scale to make massive contributions to the sustainability of the planet. The problem? I'd suspect most Wal-Mart customers don't even have a clue.

The failure of marketing a huge piece of competitive advantage

Wal-Mart's environmental moves are seem by detractors as lip service or good public relations in the face of continued labor and employment criticism. But those moves are very real, and to a point it seems natural for the world's largest retailer to give back to the environment. Wal-Mart's choice a few years ago to lumber onto the environmental bandwagon was required in a sense -- it wasn't voluntary. If it hadn't started these programs, it would probably have seen sales slump at a worse rate than they already have in the last three to four quarters.

At this time, though, the retailer is really doing some great things. However, instead of these programs being filed in the distant memories of the press, environmental groups and informed customers, Wal-Mart needs a major marketing initiative here, and it begs for introduction inside all of its regular stores, Supercenters and Sam's Clubs.

I asked eight friends and relatives this week if they knew Wal-Mart was on the ball when it came to making a meaningful and influential environmental impact. Just one person knew that they could buy "energy-saving" lightbulbs at Wal-Mart, although they did not see it as a competitive advantage. That's the issue here -- why don't Wal-Mart customers know? Because, the retailer is not telling them, instead focusing still on "always low prices." But then again, it's trying to increase sales and attempting to get away from the image as a bargain-basement price hunter's paradise. Herein likes a prime opportunity.

Getting the word on the street, in stores and on products

Wal-Mart does a dismal job of informing its customer base about all the good it does for the environment these days. Global warming, environmental impacts and energy conservation are in the media and on the nightly news very regularly -- so the American public is aware of these issues. The timing would have been perfect if Wal-Mart had begun consumer education and marketing on its green initiatives 12 months ago, but since then very little movement has been made on that front from what I have seen.

How about this: install displays, educational information (that's hard to miss) and point-of-purchase educational material -- all known as marketing -- in the most appropriate places all over the store. If a vendor's product has a small packaging footprint or is made from recycled materials, highlight it. That'll make vendors of competitive products stand up and change as well, don't you think?

In addition, the 8.5" x 11" photocopy taped to the hardware shelf that spells out the advantages of CFLs needs to go. How about a large, eye-catching display with 'at-a-glance' statistics. Try this one out (as an example): if one in 10 Wal-Mart shoppers replaced just 10 standard light bulbs in their homes with lower-energy CFLs, the country could save XX trees from being cut down. Find striking bullet points that customers can understand and easily ingest and plaster them visibly throughout the store.

Get customers "in the know" about products in Wal-Mart stores that create more environmental sustainability and let them know that even outside of product selections, the company has many more eco-friendly programs that really do make a global impact -- and they're getting better. With all the combatants that pick apart Wal-Mart for increased business with China and with poor labor practices (among other things), this is a way to highlight the positive the company is doing. It should be marketed as a top competitive advantage to goose more sales and get customers appreciating Wal-Mart again outside of the age-old "Always Low Prices" image. It's your opportunity to lose, Wal-Mart.

Stay tuned next week for another edition of The Wal-Mart Weekly. Until then, have a great -- and green -- weekend.