Eight states will combine forces to drive sales of zero-emissions vehicles to 3.3 million by 2025, underscoring a target set two years ago and seen costing automakers millions of dollars to achieve and likely increasing the vehicle sticker prices.

“The basic word here is scale,” says Mary Nichols, chairman of the California Air Resource Board. “Scaling up a program that spans the United States.”

California already has laws in place calling for one in five vehicles sold in the state to be of the ZEV variety. The seven other states, including Vermont and New York, have similar laws on their books.

“We are in the midst of transformation, and our job is to make it happen,” Nichols says from a press conference in Sacramento.

By combining their efforts under a Memorandum of Understanding announced today, the state officials say, they can share information, such as policy approaches, and generally help spread the word faster about the environmental and financial advantages of ZEVs.

“The MOU will drive action,” says Deb Markowitz, Vermont’s secretary of natural resources.

Critics say the ZEV mandate is unnecessary and market forces should be left to determine growth rates of the cars, which have struggled to gain sales momentum.

Last year, hybrid-electric vehicles, plug-in HEVs and battery EVs combined for 482,570 light-vehicle sales and a 3.3% share of the 14.4 million-unit U.S. market, according to WardsAuto data.

The laws also put jobs at stake, they say.

“Auto makers are already producing advanced-technology vehicles, and if there is market demand for them, a mandate is not needed,” Gloria Bergquist, vice president-public relations for the Alliance of Automobile Manufacturers, recently told WardsAuto.

“If there is minimal market demand and these vehicles sit unsold on dealer lots, jobs will be at stake.”

A study by the Ann Arbor, MI-based Center for Automotive Research shows that technologies necessary to achieve ZEV status can cost up to $5,270, and consumers likely would lose at least $3,000 on their purchase if gasoline prices do not rise significantly in the coming years.

ZEV proponents argue a battery EV or advanced hybrid will cost slight more, but over its lifetime can save owners up to $6,000 on fuel. Americans also do not understand the continued health risks of tailpipe emissions, they say.

The five other states joining the MOU are Massachusetts, Maryland, Connecticut, Oregon and Rhode Island.

Specific goals of the MOU, the officials say, will be drafting common building codes to make it easier to install charging stations for electric vehicles; buying ZEV products for government fleets; establishing financial incentives for consumers to buy the cars; and developing common standards for roadway signage and charging networks.

The states will develop an action plan addressing those items over the next six months. The cost to taxpayers has not been determined.

“We have not monetized it, but we have looked at how to deploy funds,” Markowitz says, citing collections from clean-air violation settlements as one source of funding.