When it comes to electric cars, buyers are often interested in two types of green.

The lower environmental impact of a zero-emission vehicle, and the potential to save cash by eliminating gasoline use are both typically factors that motivate the purchase of an electric car, to varying degrees in different individuals.

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It's also generally assumed that--for the mass market of car buyers--saving money is more important than saving the environment.

That has implications for the way electric cars are marketed, leaving carmakers to contemplate which benefits to emphasize.

Photovoltaic solar panels on roof of Honda Smart Home at UC-Davis, California

Photovoltaic solar panels on roof of Honda Smart Home at UC-Davis, California

Now, a new study suggests the environmental factor may be more important than many believe.

Participants who were reminded that conserving energy would cut air pollution used less electricity in their homes than those who were reminded only of the money they saved, according to the study results (via TakePart).

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Titled "Altruism, Self-Interest, and Energy Consumption," the study was conducted by researchers at the the University of California--Los Angeles (UCLA) and published in the journal PNAS.

At the outset, participants were asked what kinds of messages would get them to cut energy consumption.

The majority answered that it those would be messages on how much money they'd be saving. Reminders about air pollution would be less persuasive, they said.

National Drive Electric Week 2014: Eyeing a Tesla in Ottawa. Photo by Ottawa Centre EcoDistrict.

National Drive Electric Week 2014: Eyeing a Tesla in Ottawa. Photo by Ottawa Centre EcoDistrict.

Yet in practice, consumers who received messages about environmental benefits saved more electricity than those who received only messages about money.

Each household surveyed received updates comparing electricity use to that of their neighbors, to add a dash of competition.

One group was told how many pounds of pollution they were responsible for, while the other was shown the difference in electricity bills among neighbors.

The group that got the environmental messages saved more--cutting electricity use by an average 8 percent, or a remarkable 19 percent in households with children.

2014 BMW i3 electric cars waiting at East Coast shipping port for distribution, May 2014

2014 BMW i3 electric cars waiting at East Coast shipping port for distribution, May 2014

In a statement, lead researcher Magali Delmas attributed that result primarily to the "dual good" of reducing air pollution as a matter of public policy, and reducing health risks for individuals.

She said the environmental message was effective because it bundled public and private good, driving the point home for individuals.

Reminding consumers about personal health risks arguably taps into the same self-interest that motivate people to make a decision for financial reasons.

That duality between altruistic and personal motivation could make cutting air pollution a possible centerpiece for electric-car marketing.

Having two reasons to do something is better than one, after all.

[hat tip: John C. Briggs]

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