A few years ago, if you asked consumers what the No. 1 obstacle to “going green” was, they’d answer, “It’s too expensive.”

As recently as 2007, in-person interviews with dozens of women nationwide revealed that, of all the barriers between them and a more environmentally friendly lifestyle, cost loomed largest. Sure, green shoppers were often stymied over what to buy, whether the quality would hold up, and where they could conveniently make an eco-purchase, but the price of a product – real or perceived –usually posed the greatest obstacle. Did people want to be greener? Yes. Did they think they could afford it? No.

Fast forward to 2009. As the recession’s hold on the economy moves from a grasp to a stranglehold, consumers are realizing that the fundamental principles of eco-living start not with buying, but with not buying: purchasing less, sharing and swapping more, and scaling down rather than ramping up.

And guess what? All of these actions cost … nothing.

In fact, they save people so much money that many consumers are starting to feel they can’t afford NOT to be green. As just one example, consumer finance guru David Bach, writing in Go Green Live Rich, identifies four environmental lifestyle changes – bringing lunch to work, carpooling, insulating your home, and using an energy-efficient thermostat – that could save you as much as $3,758 a year. That’s more than $10 per day, real money at a time when money is generally scarce and getting scarcer.

What a difference a downturn makes.

It’s not like environmentalists haven’t been advocating simple steps like these for decades. E.F. Schumacher’s Small is Beautiful tried as early as 1973 to promote simplicity as the antidote to environmentallydestructive consumption. The Center for a New American Dream launched in 1997 with the simple mantra, “Less stuff. More fun.” Google keywords “green+living” today and 105 million links show up, connecting you to billions of admonitions to reduce, reuse and recycle.

What’s new is the public’s appreciation for the link between “eco” and “economic.” That gives people more than one reason to feel good about finding ways to avoid new purchases. Sharing, for instance, instead of buying new keeps money in consumers’ pockets – and reduces pollution, saves energy, and protects resources that might otherwise be extracted for manufacturing. At a time when many have lost as much as 40 percent of their net worth, going green is the fastest way to save money.

This is not to say that some green products aren’t in fact more expensive than their conventional counterparts. A gallon of organic milk at my supermarket costs $3 more than the brand produced by dairy cows crammed into a feedlot and pumped full of hormones and antibiotics. Organic food can cost as much as 20 percent more than food soaked in pesticides and fertilizers. “Green” cleaners that contain “cheap” ingredients like vinegar, lemon juice and water cost more than those laden with synthetic chemicals that could cause cancer.

Smart consumers adapt not by expanding but by juggling their budgets. Almost 5,000 people, mostly women, have filed balance sheets with The Big Green Purse One in a Million Campaign to show how they have shifted at least $1,000 of their household budgets to products and services that offer the greatest environmental benefit. Many say they manage to afford higher prices on green products because their eco lifestyle saves them so much money overall — on home heating, transportation and new stuff they would have formerly bought but now realize they can do without.

As One in a Million members and millions of others make these shifts – whether because of the recession or because they’ve finally gotten the message that the environment needs their help – their impact on the price of products is growing. It has to do with that basic law of supply and demand we all learned in our high school economics classes: As demand increases, so does supply, bringing prices down. The first energy-saving compact fluorescent light bulb I bought – in 1984 – cost me $25. I became the only person I knew with CFLs in my living room lamps. Today, I don’t know anyone without at least a couple CFLs in their home, at a cost per bulb of a couple of bucks.

For 30 years, I tried with varying success to inspire people to adopt low-impact living. The recession did it in about 365 days. As painful as the economic slump has been for our pocketbooks, it’s achieved for our lifestyle what no amount of environmental preaching could do: persuade people they can afford to reduce consumption and choose products that improve both the environment and their quality of life.

Diane MacEachern is an award-winning entrepreneur and best-selling author who was recently named one of America's EcoHeroes by Glamour magazine. She founded Big Green Purse to inspire consumers to use their money to protect themselves and the planet.

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