With on-demand rides available at the click of a button,?? ?? ??? it's all too easy to get into a carbon-spewing vehicle without batting an eye.

But as a Union of Concerned Scientists (UCS) study released Tuesday shows, all those rides are catching up to us. Instead of walking, biking, scooting, catching the bus, and even carpooling, too many of us are calling up our own private Uber and Lyft vehicles (and taxis, even though there are fewer of those compared to ride-hailing app options). The environmental advocacy group discovered this alarming number: Ride-hailing generates 47 percent more emissions than a private car trip. Then there's this: Ride-hailing trips are 69 percent more polluting as the trips they displace.

Displaced trips were assumed to be either public transit, taxi, or bike and walking trips, or staying home.

Mostly to blame for ride-hailing trips' extra emissions is "dead-heading," the term for when a driver is in an otherwise unoccupied vehicle while driving to or from a fare. With more Uber and Lyft drivers out there, the amount of time driving around without getting someone somewhere goes up.

These charts show different emission levels for different transportation methods:

How does your ride compare? Credit: Union of Concerned Scientists Share the ride. Credit: UNION OF CONCERNED SCIENTISTS

But it's not all hopeless. The same study found carpooling while ride-hailing in an electric vehicle mitigates a lot of the harm of ordering a private ride. The analysis determined electric ride-hailing cuts emissions by more than 50 percent compared to a private car trip. A pooled and electric ride reduces emissions all the way to 70 percent compared to a private car.

The group wrote, "Pooled trips and EVs can minimize, or even eliminate, the climate disadvantage of a ride-hailing trip."

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Both Lyft and Uber have robust carpooling options including options to walk to a shared ride. Both are heavily invested in electric bikes, traditional bicycles, e-scooters, and offering public transportation options built into the apps. In Denver, for example, the Uber Transit option maps out a public transportation-only route on city buses and lets you buy a bus ticket, all within the Uber app.

Lyft has a "green mode" to request electric and hybrid cars in Seattle and added EVs to its driver rental programs in Seattle, Atlanta, and Denver. Since 2018, Lyft has been carbon neutral through a carbon offset program. Uber has EV programs in various cities and in London set a 2025 goal to have an entire electric fleet.

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Both Lyft and Uber responded to the analysis and pointed to the myriad programs and options each company offers to reduce its environmental impact.

"We want Uber to be a part of the solution to address climate change by working with cities to help create a low carbon transportation future," an Uber spokesperson said in an emailed statement. "To unlock the opportunities we have to reduce emissions, we will continue to invest in products and advocate for policies that reduce car ownership, promote more pooled trips and support greater adoption of bikes, scooters, green vehicles and the use of public transit.”

Lyft called the UCS report "misleading" in a statement. The spokesperson continued, "Lyft encourages the use of shared rides, was the first rideshare company to put public transit information into our app, and last year, made one of the largest single deployments of electric vehicles in the nation. We are eager to continue this work in partnership with cities to advance shared, sustainable transportation."

SEE ALSO: No one should ever buy a car again. Here's why.

Among various issues with the study (it's an analysis constrained by existing data, much of which is based on studies from only a few U.S. cities), the report doesn't take into account the vehicles that people aren't buying because of the prevalence of ride-share options. Lyft's 2020 Economic Impact Report puts estimates close to 500,000 vehicles off the road because of ride-share availability. Almost 30 percent of Los Angeles Lyft riders don't own a vehicle.

No matter the issues with the study's methodology, it still stands that one of the main contributors to carbon emissions from ride-hailing (and taxis) is dead-heading. But if you start piling in passengers, dead-heading time goes down and ride efficiency goes up. Also, calling a car instead of taking a much lower-emission travel method, like walking or biking, doesn't help to cut back pollution. Ride-hailing is so accessible, however, that it's often the easiest option to get somewhere.

None of that even touches on the issue of ride-hailing and congestion, though. All of which is to say: If you are going to order that Lyft or Uber, at least make it a carpool.

Topics Uber lyft