Clean energy is coming. What's Exxon waiting for?

New York(CNN Business) BP will soon own the UK's largest electric vehicle charging company. In France, oil giant Total already controls one of America's largest solar panel makers. Even the state oil company of oil-rich Norway is launching floating wind farms.

Europe's oil industry, under fire from governments and shareholders, is grabbing a foothold in clean energy.

It's a smart way to get in on the ground floor of new technology — while hedging their fossil fuel empires for the eventual rise of renewables and electric vehicles.

Yet, unlike their European rivals, American juggernauts ExxonMobil (XOM) and Chevron (CVX) have not yet made large-scale investments in solar, wind, electric cars or energy storage. Their more cautious approach raises their risk of being left behind if the energy revolution arrives faster than they anticipate.

"Exxon and Chevron have held their fire," said Tom Ellacott, senior vice president of corporate research at energy consulting firm Wood Mackenzie.

Big Oil would have to spend $350 billion on wind and solar by 2035 to match the 12% market share it holds in global oil and gas, Wood Mackenzie estimates.

"At some point in the future, the oil and gas market will start to get squeezed as the energy transition takes off," Ellacott said.

Electric vehicles pose a long-term threat to the industry's business model. Almost half of America's appetite for crude oil comes from passenger vehicles. Yet BP (BP) thinks 320 million electric vehicles will be on the world's roads by 2040, compared with 2 million in 2016.

"Exxon thinks they can ride it out. They'll be the last to move," said Jeff McDermott, managing partner at Greentech Capital Advisors, a sustainable energy investment firm.

McDermott said that although drilling for oil has been a "damn profitable business," disconnecting from change "does not recapture the past — it loses the future."

Europe dips its toes in clean energy

Beth Comstock, former vice chair at General Electric (GE) and author of "Imagine it Forward," a book about embracing change in business, told CNN Business that BP and Norway's Equinor have done "incredibly innovative work" in renewables.

Not only is BP acquiring electric vehicle charging company Chargemaster, last year it placed a $200 million bet on solar by purchasing a stake in Lightsource, Europe's largest solar development company.

Another European oil giant, France's Total, spent $1.4 billion in 2011 to acquire a majority stake in San Jose, California-based solar panel maker SunPower (SPWR). And in 2016, Total (TOT) paid $1.1 billion to buy Saft Group, a manufacturer of lithium-ion batteries used to power electric vehicles.

Equinor, which was known as Statoil until this year, recently launched the world's first floating wind farm near Scotland. It's planning to build a wind farm off the coast of New York's Long Island by 2023.

Comstock's advice for Big Oil: "You have to look around the world, see this is happening — and at least hedge your bets."

When will the tipping point arrive?

The world is moving toward a cleaner energy future. But there's fierce debate about when the tipping point will arrive.

OPEC sees oil demand growing through at least 2040 — suggesting there's no urgent need for Big Oil to shift its thinking. No wonder Exxon is spending billions to pump oil in far-flung locales like Guyana, Mozambique and Brazil.

However, other companies believe the winds of change are blowing harder.

"The risk is there's a game-changing technology that brings forward peak oil demand," Ellacott said.

BP says demand could "plateau" during the late 2030s because of the rise of electric vehicles. Royal Dutch Shell (RDSA), which last year acquired an electric charging provider, says peak oil demand could come within 15 years. Equinor predicts a peak around 2030.

Meanwhile DNV GL, an energy-focused risk advisory firm, recently warned that peak oil is coming much sooner — in 2023.

'How do you actually make money?'

Of course, there are legitimate reasons European oil companies have been more aggressive with clean energy than their American peers. European governments are cracking down on carbon. France, Britain and Norway even want to ditch gas and diesel cars altogether. Electric vehicles made up 39% of new car sales in Norway last year, compared with 1% in the United States, according to the International Energy Agency.

Rather than worry about renewables, American oil companies are focused on capitalizing on the lucrative shale boom at home.

Exxon, which was late to the shale game, has recently invested heavily in the Permian Basin. The gushing oilfield in West Texas has made the United States the world leader in crude production for the first time since 1973. Chevron, and more recently BP, have also become major players in the Permian.

It's safe to say that money spent in the Permian will generate better returns than pumping money into renewables.

"Renewables sound good, but how do you actually make money?" said John Herrlin, an analyst covering the oil industry at Societe Generale.

However, Wood Mackenzie said that renewable projects can offer similar returns as refining — with "much lower risk." And companies will pour $200 billion per year into wind and solar projects by 2022, double the amount going into the US shale oil and gas business, Wood Mackenzie estimates.

At first blush, it may not make much sense for Exxon to get involved in renewables because it's not a power utility.

However, Wood Mackenzie argues that major oil companies have both the "engineering expertise" to succeed in complex offshore wind projects and the balance sheets to invest in large-scale solar projects. Exxon and Chevron also have vast experience working in challenging terrains and with foreign governments.

Others think Big Oil should explore powering electric vehicles. It could be a natural shift from gas stations to charging stations, albeit less profitable.

Pavel Molchanov, a Raymond James analyst, believes US oil companies will eventually do just that.

"Beyond 2025, we think electric vehicles will begin to be needle-moving for oil demand," Molchanov said.

Chevron launches future energy fund

To be sure, US oil giants have not ignored the shifting landscape. The shale gas boom prompted Exxon and others to push further into natural gas, the cleanest-burning fossil fuel. And natural gas plays a major role powering the grid that powers electric vehicles.

Last month, Exxon, Chevron and Occidental Petroleum (OXY) became the first US members of the Oil and Gas Climate Initiative. The group aims to "mitigate the risks of climate change."

"They're not running their businesses with blinders on," Herrlin said.

In a statement, Chevron said it's taking "prudent, practical and cost-effective actions to address potential climate change risks." That includes investing about $1.1 billion in carbon capture and storage projects in Australia and Canada and recently launching a $100 million Future Energy Fund to invest in "breakthrough technologies." Carbon capture is the process of preventing power plant emissions from reaching the atmosphere.

Chevron said it is using internal research and partnerships with universities to understand and evaluate the "economic viability of different energy sources."

Exxon bets on algae

For its part, Exxon has pledged to slash methane emissions by 15% and flaring by 25%. Flaring, the burning of excess natural gas at oil wells, is a significant source of greenhouse gas emissions.

Exxon defended its work on clean energy by pointing to partnerships with leading universities and other companies to come up with solutions.

"Others choose to invest in companies. Our approach is sweat equity: Let's put our best brains with any other set of best brains," Vijay Swarup, head of research and development at Exxon, told CNN Business.

For instance, Exxon has plowed more than $9 billion into lower-carbon technology since 2000, including advancements in carbon capture.

Swarup is most excited about Exxon's research over the past decade into algae biofuels as a way to power heavy-duty trucks or even airplanes. Exxon and biotech firm Synthetic Genomics recently achieved a technical breakthrough on algae by using advanced cell engineering.

"I think we're on to something. If we can solve it, this is one of the big game-changing technologies," Swarup said.

Others say Exxon should be putting its money into more advanced renewable technology.

"The future of mobility is electrification, not algae. Those investments are a mistake. That's why they are gun-shy," said McDermott.

Comstock, the former GE executive, said that all too often large businesses are scared to make bold bets on the future. Companies don't want to lose market share, and executives fear for their jobs.

"Human nature is afraid of risk. But disruptive change is coming in many different forms — and it's surprising us more often," Comstock said.

Will Exxon be the next large company caught off guard?