As state lawmakers a year ago were setting a goal of reducing Minnesota's carbon emissions 15 percent by 2015 and 80 percent by 2050, lawmakers commissioned the University of Minnesota to conduct a study to determine whether the goal is achievable, and if so, how it can be done.
Julian Marshall is a co-author of the new report.
"We can meet our objectives, but we have to get going now," he said. "We have to begin sooner rather than later."
Marshall teaches environmental engineering at the University of Minnesota. He and his colleagues at the Center for Transportation Studies examined several strategies to see how well they would work to reduce emissions.
The strategies fall into three groups -- making vehicles more efficient; developing fuels that produce fewer emissions; and providing more choices in transportation.
The authors say Minnesota needs to use all three strategies in order to meet the goals in state law.
David Kittelson, a mechanical engineer who specializes in engines and fuels, says people in other countries, including Europe and China, are already driving cars that are as efficient as new U.S. standards call for 17 years from now.
Kittleson says high gas prices are prompting Americans to demand more fuel-efficient cars, and Detroit is starting to get the message.
"We can meet our objectives, but we have to get going now."
"The American strategy was always to make a small car chintzy, a little bit noisy, a little bit frayed around edges, a little bit uncomfortable, so that you'd want to buy a bigger car," Kittelson said. "The Europeans have shown that you can make smaller cars comfortable, quiet, luxurious, and still get good fuel economy."
The report proposes what the researchers call a feebate system. The idea combines fees on gas-guzzlers with rebates for more efficient cars.
It says we need to move beyond corn-based ethanol to cellulosic biofuels which are made with non-food crops, such as switchgrass.
It adds that electric vehicles would reduce carbon emissions, but only if the electricity isn't made with coal. David Kittelson says wind power isn't the only option. He says Sweden gets one-third of its electricity from biomass, such as waste from agriculture and forestry.
"The best thing you can do to biomass is to put it into a power plant, burn it, make electricity, and use that to drive electric vehicles," Kittelson said.
In addition to more efficient cars and carbon-friendly fuels, the report says Minnesotans need to reduce the number of miles they drive. That means encouraging people to live closer to downtown, and researcher Julian Marshall says that could require some changes in zoning rules.
"For example, removing height restrictions on buildings. There are areas where people would like to build taller buildings, and zoning laws prevent that," Marshall said.
For people who want to live farther out, he says light rail and bus transit can help reduce carbon emissions, as well as carpooling.
The question is, how do legislators make those changes happen? And how do they pay for the infrastructure required?
The university researchers did not attach a pricetag to the strategies they examined. But infrastructure can be expensive.
One example is the central corridor light rail project linking the Minneapolis and St. Paul downtowns -- it's projected to cost close to $1 billion.
The Legislature passed the emission reduction goals during a 2007 session that was a high point for action on energy issues.
This year, when lawmakers were expected to follow through with more specific legislation, they accomplished less than observers expected.
They rejected the California clean car standards, which a dozen other states have signed on to. Those standards would reduce emissions a little more than the newly tightened federal standards.
Rep. Melissa Hortman, DFL-Brooklyn Park, sponsored the clean car bill, and she says lawmakers may feel pressure from their constituents to reconsider it.
"I suspect that consumers will demand that we take a second look at that," said Hortman. "I think there are a lot of people who are ready to move forward on that type of measure, considering the high gas prices."
The report says fuel-efficient cars may be a little more expensive, but the fuel savings offset the higher cost.
In the long term, the study says policymakers need to encourage shippers to move their goods by train, which is much more energy efficient than trucking.