As the price of electric vehicles (EV) has dropped by nearly half the last few years, the number of Californians driving them has gone way up. Almost 300,000 EVs now ply our roadways, up from around 10,000 just five years ago. Every major automaker has now either introduced one or plans to do so soon.

This is good news for California’s energy and environmental goals, as EVs reduce local air pollution and greenhouse gas emissions, while the batteries can soak up surplus solar or wind energy.

But this progress is threatened by a lack of available charging stations. If you’re among the forty percent of Californians who live in an apartment, townhouse, or condominium without access to dedicated parking with charging capability (even a wall outlet), you may be unable to consider buying or leasing an EV. Notably, an even higher percentage live in these types of dwellings in the state’s urban areas.

These residents need chargers in their buildings to make EV ownership feasible. Failing that, they need dedicated EV chargers at their workplaces for daytime charging, along with convenient and reliable public fast chargers (which can boost the battery to 90 miles of additional range in 30 minutes) at convenient locations, such as at neighborhood grocery stores or commercial centers.

But the state is lagging in deploying the needed infrastructure. Researchers estimate that California may need up to 220,000 publicly accessible charging ports by 2020 to meet projected demand, well beyond the roughly 12,000 available today. Hundreds of thousands of additional charging stations will be necessary at multi-unit dwellings.

This immense infrastructure deployment is unlikely to occur without policy action, which is the subject of our recent report “Plugging Away: How To Boost Electric Vehicle Charging Infrastructure” from the Center for Law, Energy & the Environment at Berkeley Law and UCLA Law. While private sector investment will address some of the need, many charging stations are simply too expensive to build and operate right now, without dependable near-term revenue to cover costs and produce a profit.

The costs are myriad, from the charger to on-site electrical installation to insurance and maintenance. Some charging station owners also face prohibitively high electricity rates, depending on their location and usage. Meanwhile, revenues to cover these costs are uncertain at best and insufficient at worst, typically coming from customer payments and on-site retail purchases as drivers shop while they wait for their vehicles to charge.

Policy makers can take steps to lower costs, primarily through incentives and permit streamlining. Examples include targeted rebates and grants for office and multi-unit dwelling building owners to install charging stations, as well as expedited permitting to allow more curbside charging. Regulators can also reduce fees for adding energy storage to charging sites to decrease electricity costs and simplify the process of connection to the grid.

These measures will help. But they will not be enough by themselves. We’ll need more robust and strategic electric utility investments in charging infrastructure, at least for any new wiring to the charging station. These investments should happen in key locations to stimulate maximum EV convenience and adoption. In addition, utilities and regulators should revise electricity rates to encourage charging at the right places and times to best meet grid needs, simultaneously saving ratepayers money and helping make the grid cleaner and more efficient.

Smart policies and innovation from automakers and battery suppliers has helped make large-scale adoption of electric vehicles in California feasible. But only with continued policy action will we see the corresponding innovation needed on the charging infrastructure side.

If we don’t get that deployment right, too many Californians will miss their chance at an electric ride.