It's clear that more public charging stations are needed to boost the practicality of driving electric cars.

And it turns out that a good place to put those stations is the location where many peoples' cars spend hours parked: the workplace.

Charging at work gives commuters who would otherwise have to rely on home charging only a little more flexibility, and it's having a significant affect.

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As part of its EV Everywhere Workplace Charging Challenge, the U.S. Department of Energy (DoE) recently conducted a survey that found employees of companies with at-work charging are 20 times more likely to drive a plug-in car.

The survey--which included all of the companies participating in the Charging Challenge--found that at workplaces where charging stations are provided, one in 73 employees drove a plug-in electric car.

That compares to the national average of one in 1,400.

Ford Fusion Energi charging.

Overall, the DoE says workplace charging has nearly doubled in roughly the past two years, going from around 2,000 charging stations installed or planned before June 2013, to just under 4,000 in May 2014.

Around 3,000 of those stations are 240-Volt Level 2 units, while the remainder are 120-Volt Level 1 stations.

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The EV Everywhere Workplace Charging Challenge was started in 2013 with the goal of achieving results like these.

The DoE provides companies with information on charging stations and installation, as well access to experts from charging-network operators, companies that already offer workplace charging, and other relevant groups.

It quickly grew from just 13 "founding partner" companies in 2013 to more than 150 today. Together, these companies account for more than 300 workplaces and around 600,000 employees.

MetLife electric-car charging station for employee use - Dayton, Ohio

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That's the equivalent of saving 800,000 gallons of gasoline, cutting 5.5 million pounds of greenhouse-gas emissions, and displacing 1,500 average internal-combustion cars from U.S. roads.

The DoE hopes to achieve even greater workplace-charging growth by the time of the Charging Challenge's conclusion in 2018, so hopefully it will be able to keep up the momentum established so far.

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