If you want to get someone to do something—drive an electric car, say—then making it cheaper is a good way to start.

Purchase incentives and tax rebates have been a powerful tool for boosting electric-car adoption.

But there's another form of incentive that could yield impressive results as well.

DON'T MISS: Why I bought a new Nissan Leaf electric car 2 hours from home: $8,500 net cost

Group-buying programs have led to a spike in electric-car sales in certain regions, notes the Southwest Energy Efficiency Project (SWEEP).

These programs—typically partnerships between local governments and dealers—leverage collective buying power to lower prices for individual consumers.

Similar to a company making a fleet purchase, guaranteeing a given sales volumes makes dealers willing to cut prices on a group of cars.

2015 Nissan Leaf

2015 Nissan Leaf

Residents of a participating constituency have a limited time to take advantage of these discounts, which can be substantial.

One program run by the Colorado counties of Boulder, Adams, and Denver cut the price of a 2015 Nissan Leaf S for residents by $8,349.

Combined with Federal and state incentives, that effectively reduced the price of this model from $29,860 (including destination) to less than $13,000.

ALSO SEE: Group Buy Of Fiat 500e Electric Cars Ignites 'Feeding Frenzy,' 100-Plus Bought (Mar 2015)

And that apparently got the attention of car buyers.

In the areas where the discount was available, dealers sold 248 Leafs in four months last year, more than doubling their sales from the same period in 2014.

Sales from the program accounted for 5 percent of U.S. Leaf sales between September and December 2015, SWEEP claims.

2015 Nissan Leaf

2015 Nissan Leaf

Perhaps most critically, a survey of participants found that 72 percent did not intend to buy an electric car before the group-buy program.

The same program also included home solar power systems, of which 147 were sold as well.

MORE: Electric Cars: What's Needed To Eliminate Gasoline, Diesel In 25 Years (May 2015)

Group buying has yielded impressive results for other municipalities in the region.

A program in Ford Collins, Colorado, boosted year-to-year Leaf sales at a local Nissan dealership from 15 to 52.

2015 Nissan Leaf

2015 Nissan Leaf

Another in Salt Lake City is credited with 75 electric-car sales over six weeks.

That's nearly double the amount for the entire state of Utah during the same period the previous year.

It shows that while purchase incentives may be good, the even bigger potential discounts of group-buy programs could be even more enticing to consumers.

After all, who doesn't love a good deal?


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