Several credit-card companies are unveiling new “green” cards that will allow users to channel a percentage of their spending toward efforts to cut greenhouse-gas emissions, reports The Wall Street Journal.

Among the companies, General Electric’s Earth Rewards MasterCard targets as much as 1 percent of total spending on the card toward emission-reduction projects, while Bank of America’s Brighter Planet Visa matches every dollar spent with one point that can be accumulated and traded in for “carbon offsets.”

Although such cards have been available in Europe for several years, environmentalists in the United States are concerned about the lack of transparency surrounding carbon offsets in a voluntary market. Some critics, such as Leslie Lowe, director of the Interfaith Center on Corporate Responsibility on Energy and Environment, a nonprofit group in New York, wonder whether this method is an effective means to reduce greenhouse-gas emissions. “What I am more concerned about is that it gives people an easy pass: ‘OK, I’ve got my green credit card, so I can do things that are carbon-ridiculous,’” she said.

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