We've all seen those gently worded, politically correct suggestions in our hotel rooms - "____ gallons of water are used each day cleaning towels and sheets that have been used just once..." While guests are invited to re-use sheets or towels in the name of environmental friendliness, the conservation serves another purpose -- lowering housekeeping costs.

With occupancy rates on the decline, hotel chains are looking for ways to limit expenses, and one of these ways is by reducing housekeeping efforts. Some Wyhndham Worldwide (WYN) chains, such as Howard Johnson, Ramada, and Super 8, leave linens unchanged whenever possible. WYN's Days Inn chain is soon going to adopt a three-day change rule (I'm assuming all hotels still change between guests, regardless of the length of stay).

Ed Begley, Jr. will soon have more options should he be in need of a new electric car. Daimler AG has announced the acquisition of an equity stake of nearly 10% in Tesla Motors (not to be confused with these guys -- five man electrical band, indeed).

The German-based automaker is teaming up with the California company to work on making electric cars "a reality." Tesla is a visionary on the electric-car front; its Roadster, which runs on battery power, is the only electric vehicle approved for highway use in both Europe and North America. (Of course, it also comes with a price tag of $101,500 -- you'd have to save a lot on gas to make up for not buying a Taurus).

TechCrunch reports that Greenpeace is chiding Apple Inc. (NASDAQ: AAPL) for the iPhone's toxic chemical ingredients. Moreover, Greenpeace's analysis suggests that the iPhone is losing "green ground" to other mobile phone competitors which are in the process of eliminating the iPhone's toxic chemicals.

According to Greenpeace, the iPhone contains toxic brominated compounds (indicating the presence of brominated flame retardants (BFRs)) and hazardous PVCs. Two of the "phthalate plasticisers" found at high levels in the iPhone headphone cable are classified in Europe as 'toxic to reproduction, category 2′ and are banned from use in all toys or childcare articles sold in Europe.

Greenpeace's analysis of competitors is most interesting: Nokia Corp. (NYSE: NOK) is totally PVC free while Motorola Inc. (NYSE: MOT) and Sony Ericsson already have products on the market with BFR free components. I am in Greenpeace's camp on this one. I also think that if Apple cleaned up the iPhone, it would find that green means green -- particularly in Europe.

That's something that Apple shareholders and Greenpeace would both celebrate.

Peter Cohan is president of Peter S. Cohan & Associates. He also teaches management at Babson College and edits The Cohan Letter. He has no financial interest in the securities mentioned.

When I read about Wal-Mart Store's (NYSE:WMT) embrace of environmentally friendly light bulbs, I took a quick peak outside the window of my home office. To my surprise, the world as I know it didn't come to an end.

The problem I have with doing right by the environment (besides laziness) is that it's expensive and often requires government subsidies. That's what makes Wal-Mart's plans to sell compact fluorescent lights so interesting. These bulbs are eight times as costly as traditional incandescent bulbs but produce less greenhouse gasses. Wal-Mart wants to sell 100 million of the environmentally friendly light bulbs, which today make up 6 percent of the market, by 2008.

Wal-Mart's skeptical suppliers went along. After all, this is Wal-Mart, the last company any of them wants to annoy.

While Wal-Mart has increased sales of the greener lights, it's only one of many ambitious environmental goals which USA Today says includes reducing the amount of gas used by its trucking fleet, buying fish only from sustainable fisheries, as well as reducing sold waste and energy use at its 7,000 stores. USA Today says Al Gore's movie "An Inconvenient Truth" got a standing ovation when it was shown at Wal-Mart's headquarters.

Wal-Mart's critics argue that this green effort is merely a PR stunt. Other groups who have fought the retailers on many issues for years seem to be surprised that Wal-Mart has embraced the environmental movement. There may be some spin with Wal-Mart's green push, but it will be interesting to see if the huge company can make a big difference in making environmentally-friendly technology more economically viable.