PORTLAND, Ore. (AP) — Stephanie Terrell bought a used Nissan Leaf last month and was excited to join the wave of drivers adopting electric vehicles to save on gas money and reduce her carbon footprint.

But Terrell quickly encountered a bump in the road on her journey to clean driving: As a renter, she doesn't have a private garage where she can power up overnight, and the few public charging stations near her are often in use, with long wait times. On a recent day, the 23-year-old nearly ran out of power on the freeway because a public charging station she was counting on was busy.

"It was really scary and I was really worried I wasn't going to make it, but luckily I made it here. Now I have to wait a couple hours to even use it because I can't go any further," she said while waiting at a different station as a half-dozen EV drivers circled the parking lot, waiting their turn.

The great transition to electric is well underway for single-family homeowners who can charge their cars at home overnight, but for millions of renters like Terrell, access to charging remains a significant barrier to owning a zero-emissions vehicle. People who rent are also more likely to buy used EVs that have a lower mileage range than the latest models, making reliable public charging even more critical for them.

Now, cities from Portland to Los Angeles to New York City are scrambling to come up with innovative public charging solutions as drivers string power cords across sidewalks, stand up their own private charging stations on city right-of-ways and create long lines at overburdened public facilities.

The Biden administration last month approved plans from all 50 states to roll out a network of high-speed chargers along interstate highways coast-to-coast using $5 billion in federal funding over the next five years. But states must wait to apply for an additional $2.5 billion in local grants to fill in charging gaps, including in low- and moderate-income areas of cities and in neighborhoods with limited private parking.

"We have a really large challenge right now with making it easy for people to charge who live in apartments. It's a large percentage of the U.S. population and .... depending on what part of the country you live in, it could easily be 50% of the population," said Jeff Allen, executive director of Forth, a nonprofit that advocates for equity in electric vehicle ownership and charging access.

Nationwide, there are about 120,00 public charging ports featuring faster Level 2 charging or above and nearly 1.5 million electric vehicles registered in the U.S. — a ratio of just over one charger per 12 cars nationally, according to U.S. Department of Transportation data. But those chargers are not spread out evenly: In Arizona, for example, the ratio of cars to charging ports is 18:1 and in California, which has 39% of the nation's EVs, there are 16 zero-emissions cars for every charging port.

Electric vehicles can charge on a standard residential outlet, or Level 1 charger, but reaching a full battery from empty can take up to 50 hours, so most public chargers are Level 2 or faster. Experts say the demand for charging — and particularly for Level 3, which can fill an empty battery in an hour or less — will only increase as more drivers take advantage of new EV tax incentives and as some states, like California, begin to phase out gas vehicles entirely.

A briefing prepared for the U.S. Department of Energy last year by the Pacific Northwest National Laboratory forecasts a total of just under 19 million electric vehicles on the road by 2030, with a projected need for an extra 9.6 million charging stations to meet that demand.

In Los Angeles, for example, nearly one-quarter of all new vehicles registered in July were zero-emissions cars. The city estimates by 2035, it will have to expand its distribution capacity anywhere from 25% to 50%, with roughly two-thirds of the new power demand coming from electric vehicles, said Yamen Nanne, manager of Los Angeles Department of Water and Power's transportation electrification program.

Amid the boom, dense city neighborhoods are rapidly becoming pressure points in the patchy transition to electrification, with EV owners who rent stringing cords across public sidewalks and jerry-rigging charging stations on their own. Those who aren't willing to do that flock to public charging stations and often have to wait in line or circle the parking lot until a charger is free.

To meet the need, U.S. cities and the utilities that serve them are scrambling to add infrastructure now while also crafting policies to ensure charging capacity and equitable access are baked into future development.

In Los Angeles, the city has installed over 500 electric vehicle chargers — 450 on street lights and about 50 of them on power poles — to meet the demand for public charging and has a goal of adding 200 chargers per year on light poles, Nanne said. The chargers on street lights are strategically installed in areas where there are apartment complexes or near amenities and draw from the same electric connections that feed the lights, he said.

Similar initiatives to install pole-mounted chargers are in place or being considered in cities from New York City to Charlotte, N.C. to Kansas City, Missouri and the utility Seattle City Light is in the early stages of a pilot project to install chargers in neighborhoods where EV owners can't charge at home through an opt-in process.

Other cities, like Portland, are working to amend building codes for new construction to require electrified parking spaces for new apartment complexes and mixed-use development. A proposal being developed currently would require 50% of parking spaces in new multi-family dwellings to be wired for electric and all spaces would need to be pre-wired in complexes with five units or fewer.

The city's Bureau of Transportation is also working on new policies that would allow charging infrastructure in the public right-of-way in areas with a high density of multi-family dwellings and mixed-use buildings to address equal access for lower-income residents.

Policies that provide equal access to charging are the priority because with tax incentives and the development of a robust used-EV market, zero-emissions cars are finally within financial reach for lower-income drivers, said Ingrid Fish, who is in charge of Portland's transportation decarbonization program.

The initiatives mimic those that have already been deployed in other nations that are much further along in EVadoption.

London, for example, has deployed 4,000 public chargers on street lights to make charging accessible while spending about one-third of the amount it would cost to wire a charging station from the sidewalk, said Vishant Kothari, manager of the electric mobility team at the World Resources Institute.

But London and Los Angeles have an advantage over many U.S. cities: Their street lights operate on 240 volts, the same current strength needed for EV charging. Most American cities' street lights operate on 120 volts, which would take hours to charge a vehicle, said Kothari, who co-authored a study on the potential for pole-mounted charging in U.S. cities.

That means cities considering pole-mounted charging must also come up with other solutions, from zoning changes to pre-wiring new apartment complex parking lots for EVs to policies that encourage workplace fast-charging.

Yet changes can't come fast enough for renters who already own electric vehicles and are struggling to charge them.

Rebecca DeWhitt rents a house but isn't allowed to use the garage. For several years, she and her partner strung a standard extension cord 40 feet from an outlet near the home's front door, across their lawn, down a grassy knoll and across a public sidewalk to reach their Nissan Leaf on the street.

They upgraded to a thicker extension cord and began parking in the driveway — also a violation of their rental contract — when their first cord charred from the strong current and stopped working. Now, it takes them up to two days to fully charge their new Hyundai Kona using their home outlet or they must drive to a nearby grocery store and wait for one of two fast-charging stations.