The lesson of Green Week, Cramer said Friday, is that idealism and investing don't mix.
"Whether a company helps or hurts the environment shouldn't be an issue," Cramer explained. "You're looking for stocks that can go higher."
If not green, consider this "slightly less brown" industry: filtration and separation. Unlike traditional green stocks, like wind or solar names, filtration plays are actually working in this environment. Buildings and cars need air filters and industry processes require types of filtration, too. In the health field, there's a need for medicines that are sterile, foods and beverages that are pure and the same technology helps prevent the spread of disease by filtering blood.
Cramer likes two plays on filtration and separation, including Pall and Donaldson . Pall splits its business between industrial filtration and health filtration. The key with the filtration business is that customers are constantly having to buy replacement filters. That's why Pall gets three-quarters of its revenue from recurring consumables. It's well-balanced, too, with about a third of their business in the Western Hemisphere, a third in Europe and the final third in Asia. Pall's cash flow is expected to double from 2010 to 2013 thanks to cost cuts and new product sales.
With Donaldson, 58 percent of sales from from the company's engine business, where they make filters for off-road equipment, like construction, mining and farming equipment. The rest of the company's sales comes from dust collectors, compressed air purification systems and the like. Donaldson's outlook for both engines and industrial was incredibly bullish when they reported quarterly earnings Thursday. The company had a 12 cent beat and raised guidance for 2011. Cramer thinks this stock has room to run, too.
Call Cramer: 1-800-743-CNBC
Questions for Cramer? email@example.com
Questions, comments, suggestions for the Mad Money website? firstname.lastname@example.org