More than four years after the first modern electric cars went on sale in significant numbers, concerted efforts by carmakers, governments, and assorted advocates have ensured a modicum of success.

But what more would it take to move electric cars from the small niche they currently occupy to the dominant form of vehicle?

Advocacy group Plug-In America believes it's not only possible for electric cars to replace internal combustion, but that the right policy moves could see that happen within 25 years.

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The group issued a report last week surveying efforts to promote electric cars between 2011 and today. It concluded that a unifying force is needed to replace the current disparate efforts to promote electric cars.

It identified a "patchwork quilt" of inconsistent government policies, and advocacy efforts that rely too heavily on the whims of carmakers and other corporate interests as impediments to greater electric car adoption.

The report includes 11 "key findings" in three main areas: marketing, public policy, and potential support networks.

Tesla Model S 85D, 2015 Detroit Auto Show

Tesla Model S 85D, 2015 Detroit Auto Show

Not just selling cars, raising awareness

On the marketing front, Plug-In America calls for a broader effort that promotes electric cars as a category, rather than relying manufacturers' promotion of individual models.

The report notes that electric cars sell well in major metropolitan areas on both coasts--but not in the middle of the U.S.

ALSO SEE: Which Electric Car Dominates Sales In New York State?

To expand sales, Plug-In America advocates a broader range of models, noting that many of the current offerings are "compliance cars" offered in a limited number of states.

It calls for carmakers to market models nationwide, offer a greater range of vehicle types including trucks and SUVs, and encourage dealers to promote them actively.

Promotional efforts outside the car industry were also recommended, including a national ad campaign along the lines of the dairy industry's "Got Milk" campaign, and a "Twenty Million Test Drive" initiative to get more people to experience electric driving.

Chevrolet Spark EV at CCS fast charging station in San Diego.

Chevrolet Spark EV at CCS fast charging station in San Diego.

Policy goals

The report also calls for greater alignment of policies that promote electric cars on a national level.

That means taking policies that have worked in certain states and municipalities and spreading the knowledge to other areas, the authors say.

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It also means standardizing things like charging-station signage and metrics for targets of electric-car adoption, which the authors suggest could be expressed in vehicle-miles traveled.

Even when policies are in place to promote electric cars, the report claims their effectiveness may be limited.

It criticizes what authors call the "one-size-fits-all" approach of emphasizing public Level 2 charging.

BMW i3 and Volkswagen e-Golf electric cars using Combined Charging System (CCS) DC fast charging

BMW i3 and Volkswagen e-Golf electric cars using Combined Charging System (CCS) DC fast charging

It says charging-station installations in a given area should be allowed to include a greater variety of options--including Level 1 and DC fast charging--with decisions informed by user data where available.

And while policies like the Federal tax credit for electric cars (with a maximum battery size of 16 kilowatt-hours) and California's zero-emission vehicle mandate have been helpful, the report's authors say they may also hinder development of electric cars as a market segment.

Carmakers presently have no incentive to develop models with longer ranges, or sell cars nationwide, they say.

Solidifying support

Just as it advocates greater focus in marketing and policy, Plug-In America says lobbying efforts on behalf of electric cars should solidify.

While electric-car ownership is generally associated with the political left, the report's authors argue that there is significant bipartisan support--and that it should be harnessed through the creation of "PEV Caucuses" at the Federal and state levels.

National Drive Electric Week 2014: Peeking under the hood in Perrysburg, OH. Photo by Michael Hall.

National Drive Electric Week 2014: Peeking under the hood in Perrysburg, OH. Photo by Michael Hall.

Another potential resource of support cited is the cohort of electric-car drivers themselves.

They can be among the most persuasive advocates for electric cars, and are generally highly visible in their communities, the report says.

Finally, Plug-In America believes philanthropic organizations can provide valuable resources for supporting electric cars in their current early stage of development.

Will this blend of public policy, corporate marketing, and individual advocacy bring electric cars into the mainstream over the next two and a half decades?

Stay tuned.

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