Even in the biggest electric vehicle markets, a driver venturing too far from home can have a hard time finding a place to recharge.

Try your luck on California’s Pacific Coast Highway. The roughly 600-mile route between San Diego and San Francisco has dramatic sea cliffs, off-the-grid retreats, lush vineyards—and, in some long stretches, few places to recharge for anyone who isn’t behind the wheel of a Tesla Inc. car.

California is home to about half the battery-powered passenger cars in the U.S. and does more than almost anywhere else to encourage EVs, but that doesn’t mean it’s always easy to plug in. Drivers face similar frustrations outside of China’s major urban hubs and on road trips through Europe. Executives in the nascent charging industry, drawing investment from automakers and energy giants alike, know that limited infrastructure has become a chokepoint.

“It’s a pretty rubbish experience charging a car today,” Roy Williamson, vice president of oil giant BP Plc’s advanced mobility unit, which is investing in charging operators and technology companies, said at a BloombergNEF conference in San Francisco this month.

The first thing needed is more places to plug in. The global electric-vehicle fleet reached 5 million last year, according to BNEF, supported by a little more than 600,000 public charging points around the world.

Under a scenario where EVs hit 30 percent market share by 2030, the International Energy Agency projects a need for somewhere between 14 million and 30 million public chargers deployed globally to serve regular passenger vehicles.

Today’s limited infrastructure isn’t created equally. About half of existing public chargers are concentrated in China, by far the top EV market, and more than two-thirds globally are slower units that may add only 10 miles of power for every 30 minutes at the plug. The best-performing EVs are capable of driving more than 200 miles on a full charge, which means anyone who finds an out-of-date charger risks an hours-long wait before their batteries are filled.

That means drivers can have wildly different experiences depending on where they recharge. A regular household wall socket can take about 12 hours to replenish a battery run down to 20 percent, although if this takes place overnight it will hardly be a problem. Hooking up to a charger capable of medium speeds—available at the homes of some EV owners, alongside highways or in a shopping-mall parking lots—will add between 10 miles and 60 miles of driving range per hour. The most common fast chargers can add at least 75 miles in 30 minutes, at a premium cost, although most still fall short of the dream of matching the 10-minute time it takes to refill at a gas station.

There’s also nowhere near standardization of the charging infrastructure itself. Some charging points, such as those owned by Tesla, are designed with plugs that won’t work with rival electric car models; others might require clunky adapters. The price of charging outside the home can vary wildly and sometimes require a cumbersome array of subscriptions or mobile apps. The U.S. has three charging standards, compared to one in China.

“Using an electric car to run long distance is a fake proposition at the moment,” said Beijing-based Chen Zhen, who owns two EVs, including a Tesla Model S, but uses a gasoline-powered car for trips outside the city. Charging at public facilities costs Zhen more than double the price he pays for electricity at home, while units are often out of service or incompatible with his cars. For many drivers, he said, “if they don’t have charging facilities at home, buying an EV would only cause them trouble.”

While for now about 80 percent of EV charging is done at home or the workplace, the roll-out of millions in additional public charging points is seen as crucial to give motorists enough confidence to ditch combustion-engine models. That balance of charging inside or outside the home is also seen shifting as EV prices fall and the vehicles are increasingly purchased by drivers who don’t have space to park within plug’s reach of their home. Already, it’s not uncommon to see power cords trailing from upper-floor windows of Chinese apartment blocks to charge vehicles parked at street-level, according to a report published this month by Columbia University.

Some markets are also proving to be a conundrum. In Norway, low volumes of public chargers haven’t impeded the rise of EVs, which now account for about half of new vehicle sales. Germany, on the other hand, has more chargers than any country besides the U.S. and China—and EVs make up about 2 percent of sales.

In Britain, where EVs are relatively scarce, planners aren’t sure how to proceed. “Do we build out now and hope the demand kicks in? Or do we wait and then build the infrastructure, leaving consumers waiting?” said Graeme Cooper, project director of electric vehicles at National Grid Plc, the U.K.’s power and gas network operator. But markets with healthy demand find infrastructure a similar puzzle: “Getting even to 7 million electric vehicles in California by 2030, and the charging that is needed for that, is going to be a huge lift,” Drew Murphy, Southern California Edison’s senior vice president of strategy and corporate development, said in an interview.

In the short term, the EV industry faces a chicken-or-egg scenario: A lack of sufficient charging points is seen as a factor holding back adoption, yet low rates of EV penetration mean the economics of building new charging stations are challenging. Fast-charging stations need at least eight customers each day to break even, according to BNEF, but today the average public charger in some markets sees less than five customers.

“Consistent profits are elusive today,” Brett Hauser, chief executive officer of Greenlots, a Los Angeles-based provider of hardware and software to manage charging stations, said at the BloombergNEF summit in San Francisco. EV charging is “one of the biggest pain points, given how hard it is to finance and operate a standalone unit,” said BNEF analyst Salim Morsy. “You’ll need to see regulatory support.”

New Jersey has just five public chargers for every 100,000 residents, said Ralph Izzo, chief executive officer of Public Service Enterprise Group Inc., which owns the state’s biggest utility. So it’s proposing about $364 million of electric vehicle-related infrastructure, the bulk of which is for single- and multi-family home charging.

Automakers who are eager to lure customers for their rapidly expanding electric lineups have started taking action.

Tesla built charging stations and networks on four continents to help spur car sales and fill massive gaps in infrastructure. The electric automaker is one of the only operators to have charging stations in both the U.S. and China. An alliance of Volkswagen AG, Daimler AG, Ford Motor Co. and BMW AG, meanwhile, plans to build a total of 400 charging stations across Europe by next year, seeking to add charge points about every 120 kilometers along the continent’s highways.

Volkswagen’s Electrify America unit plans to spend $2 billion to support zero-emission vehicles in the U.S., including $800 million in California. This week the company announced it had 105 electric-vehicle charging sites in the U.S. and plans to have 484 built by July 1. It’s a quick ramp-up: At this point last year, Electrify America had zero ultra-fast charging sites.

The company, seeded with money from VW’s diesel-gate settlement, is building an open network available to most EVs, including some Tesla models. “The flood of cars is coming,” said Brendan Jones, Electrify America’s chief operating officer.

The world’s EV sales jumped 82 percent last year, and electric models are expected to account for a third of the car fleet by 2040, according to BNEF. The coming boom is spurring utilities, oil and gas companies and other new entrants to join automakers in investing in a charging industry that’s so far been dominated by little-known companies.

For oil firms that dominated the gasoline market, it may also be about protecting turf. “We’ve always looked at this as a land grab,” said Michael Farkas, chief executive officer of U.S. incumbent Blink Charging Co., in an interview.

Royal Dutch Shell Plc will be the first oil major to own a U.S.-based charging service outright after closing its acquisition of Greenlots, according to BNEF. Rival oil giants Total SA and BP, along with companies producing fuel pumps and gas station equipment, are also making investment and acquisitions.

What’s clear is that charging options aren’t likely to replicate the combustion engine-era’s networks of highway gas stations. Motorists will want their car to recharge wherever it’s parked, while they shop for groceries or spend a day at work, rather than make a specific stop for charging, said Ford’s Rebecca Shelby, manager of electrification policy and standards, at the BNEF summit.

Future innovations may also include socket-free wireless charging. XCharge, a Beijing-based supplier of charging technology to stations in more than 50 cities in China, is working to use robotic arms to help charge driver-less cars.

For now, there are marked differences in how charging infrastructure is developing in different markets. Automakers are playing a larger role in the U.S., while in China—where charging infrastructure was dominated by state-owned utility companies until about 2015—the majority of points are being installed by hardware manufacturers or other private operators, according to Colin McKerracher, a London-based analyst at BloombergNEF.

There’s a contrasting role from governments, too. China’s federal policymakers are promoting development of charging networks with funding, targets for installations and by mandating standards. In the U.S., there’s a more modest approach at a federal level, according to Columbia University’s study, although some states are taking an active role.

Charging network operators need to prepare for new consumers in the next decade who’ll be less tolerant than early adopters. Current EV drivers are “pretty smug” and willing to trade “quite a lot of pain” in exchange for the kudos of going electric first, BP’s Williamson said. He included himself in that number.

For EVs to go from “crazy boutique small to mainstream,” the industry needs cheaper vehicles that can drive further on a single charge, EVgo’s Cathy Zoi said in a Bloomberg Television interview. And, she added, “there has to be charging infrastructure everywhere.”