Last week, I explained a dismaying reality for planet-savers everywhere: Not even mega-blowout sales for Tesla’s new Model 3 sedan are enough to substantially green and decarbonize our global transportation system. There are simply too many cars on the road and too many new cars sold each year — the vast majority of which run on gasoline, not electricity, and will for some time.

What this means is that we’re probably now at the beginning of a gradual, rather than rapid, electrification of the transportation sector. Yeah, it’ll help out when it comes to greenhouse gas emissions — especially as the electricity that powers Teslas and other electric cars also becomes greener — but it probably won’t do so fast enough to save us in the critical two decades or more when all the big decisions about the planet’s future need to be made.

So how is it possible to scale up faster? Well, one answer may come by looking at the example of a country that has already done just that: Norway, where electric vehicles were fully 18 percent of new cars sold last year.

In a new paper in Applied Energy, Måns Nilsson of the Stockholm Environment Institute and Björn Nykvist of the KTH Royal Institute of Technology in Stockholm examine the policy moves that made this kind of high growth possible, using Norway and several other examples from around the world to drive their analysis.

The gist? You essentially need two things — public policies that address the current higher cost of these vehicles (through tax breaks or rebates) until those costs decline, and then other public policies that do something else: Get past people’s psychological blocks when it comes to driving electric vehicles. That’s a very big issue when people are used to pumping gas rather than charging, and so develop ‘range anxiety’ — the fear that their EV will run out of juice far from a recharging station.

“When you start to change some of the economic incentives, you get the first movers,” says Nilsson. “But then what we have seen is this norm change, that it’s like a cultural shift in certain pockets, typically certain communities, it could be certain suburbs, certain cities, where the electric car becomes the norm.”

In some key ways, Nilsson cautions, Norway isn’t an easily replicated example. Not only is it a wealthy country to begin with, but vehicle taxes are extremely high in the country, which means that special tax breaks for electric vehicles make them quite financially competitive.

“They have this incredibly high purchasing tax on cars,” Nilsson says. “They’ve had a tolerance for extremely expensive cars. They’re more than twice as expensive in neighboring countries. What they did with electric ones was they basically gave a tax extension. So a Tesla became on par with a regular Volvo or Volkswagen.”

Indeed, one recent study found that in Norway, a Tesla Model S that would normally cost $ 140,000 instead cost about $ 70,000 to purchase. “The financial incentives [for EVs] … are particularly strong incentives due to Norway’s high level of vehicle taxation,” the paper noted.

So the analogy is limited — but still, the general principles can still apply. Norway has used government incentives and subsidies to prompt EV purchases — offsetting the relatively high cost of the vehicle, which in turn, is substantially driven by the cost of the battery — while also using policy to speed up changes in drivers behaviors’ and habits and thus, more quickly normalize electric vehicle use. Those additional policies include giving EV owners free public parking, free use of toll roads, and using government funds to set up a large network of (free) charging stations.

The Applied Energy paper, accordingly, outlines what is termed a “breakthrough scenario,” in which global electric car growth is not merely incremental (which seems to be what we are currently looking at in the U.S.). Rather, it blows up fast, with global electric vehicles approaching 70 percent of all cars sold in 2030, and nearly 30 percent of the overall vehicle fleet.

But to get there, well, you need government policy. “The breakthrough scenario is strongly dependent on a stronger public policy signal that inspires both business and consumer confidence. It is also strongly dependent on continued rapid cost reduction of battery packs,” write the authors. They continue: “Public and private investment in charging infrastructure are keys in the breakthrough scenario, not just for directly enabling charging, but also to support the build-up of user confidence and enhance the norm and perception of the BEV [battery electric vehicle].”

Policies embraced in the paper therefore include major deployment of electric vehicle charging infrastructure and requirements that manufacturers build electric vehicles.

To see why norms and perceptions are so important, consider some recent research by the National Renewable Energy Laboratory (NREL), which underscores that many American consumers just aren’t ready, psychologically, for electric cars. The survey of 1,015 Americans found that just 18 percent of people were aware of the locations of charging stations on driving routes with which they were familiar, and only a little more than half could park near an outlet at home. Most important — and signaling the “range anxiety” problem — the study concluded that “A pure electric vehicle would need to be able to travel 300 miles on a single charge for 56% of respondents to be willing to consider purchasing one.”

That’s pretty odd, given that few if any of us drive 300 miles daily or on our commutes. But it certainly underscores the need for a major change in public attitudes and awareness. To do this, the new Applied Energy study envisions governments building massive installations of nationwide charging stations, and also pushing car manufacturers to make an electric transition.

So is there any place in the U.S. where this is actually happening?

Here, we don’t need to look all the way to Norway but rather to California, where manufacturers are required to make a percentage of their cars “zero emission” vehicles.

California, indeed, is the closest U.S. equivalent to a place like Norway, with multiple laws promoting electric vehicles and, according to the state’s Plug-in Electric Vehicle Collaborative, sales of 196,447 cars since 2011, compared with 428,816 sold nationally — or nearly half of all EVs sold in the United States.

EVs are about 3 percent of new California car sales at this point, says Gennet Paauwe, communications adviser to the collaborative. And this is the result of both things that are distinctive about the California — people drive a lot, there are big and longstanding problems with air pollution, the state is a leader in fighting climate change — but also public policies.

“We’ve got incentives for people to purchase these cars,” says Paauwe. “They range from carpooling access to the state rebate program.” The state gives as much as $ 6,500 to purchasers of zero-emission vehicles, which is on top of a federal credit of up to $ 7,500.

Granted, California isn’t Norway for many reasons — including because it doesn’t have the huge initial vehicle tax, and because U.S. gas prices are cheaper. “Gas prices in the US are now, it’s like a third of in Europe,” says Nilsson. “So I think it’s basically this economics factor.”

Still, current policies have already been enough to set California apart from the rest of the U.S. And there’s a feedback: In California, more people drive electric cars, which means that more people see electric cars on the road and around — and their use becomes more rapidly normalized.

So, right now the U.S. and much of the world may be on a moderate growth past for electric vehicles — but there’s no requirement that that be the case. It’s just that for things to move faster, we’d probably have to make a lot more use of that exceedingly controversial tool of change — government.

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