Making Black Cars Green

Now that congestion pricing is behind us (at least for now), attention can turn to other PlaNYC 2030 proposals to lower the carbon footprint of some of the traffic we see every day in our city.

To do that, the Taxi and Limousine Commission recently approved regulations will increase the fuel economy of all new "black cars" that service the city's business community to a minimum of 25 miles-per-gallon (mpg) next year and to a minimum of 30 mpg beginning in 2010.

The proposal to green the city's roughly 10,000 black cars is an obvious follow-up to last year's regulation that is, slowly but surely, converting the city's yellow cabs to fuel-efficient hybrids, thanks to Local Law 72 of 2005.

Switching to more fuel-efficient models (whether hybrid or not) cuts fuel costs for drivers and operators, while reducing the global warming impacts of the overall industry.

Though this new regulation is well intentioned, it may not provide as much global warming as possible.
The Myth of MPG

Here's why: the use of "mpg" ratings (set by the U.S. Environmental Protection Agency for all cars sold in the U.S.) as the performance indicator is an imperfect way to measure the global warming impact of these vehicles. It's imperfect for two reasons.

First, the agency's mpg ratings are flawed because they are based on the agency's assumptions regarding the typical style of driving in cities and on highways across the nation. These assumptions bear no relationship to the way black cars are actually driven in New York City. To put it as simply as possible, EPA assumes cars drive faster, sit in less traffic, idle less, and use less air-conditioning than any city black car.

Second, mpg ratings are imperfect because there are significant, so-called "upstream" global warming emissions that stem from the manufacturing and transport of the vehicles to New York, as well as from the production, refining, processing and/or transport of whatever fuel is used (i.e., gasoline, diesel, biofuels, or alternative fuels such as natural gas or electric power). The agency's ratings govern only the amount of fuel that one can expect to use in typical city or highway driving, not the actual global warming pollution that comes from the driving (and the production) of the car.
A Footprint Approach

A more comprehensive approach would be to measure the full, life-cycle "carbon footprint" of the vehicles. Such an approach would ensure that the city is driving the black car industry towards the vehicles that provide the least amount of global warming pollution.

Of course, requiring car fleets to calculate their carbon footprint is a bit harder than simply reading the EPA mpg ratings. So, a practical solution would be to give fleets a choice: fleets could choose to comply with the regulation simply by using vehicles that meet the mpg threshold —- or they could use vehicles that provide, on a life-cycle basis, an equivalent or better carbon footprint. Providing this option would open the door to alternative fuel vehicles that may have very low upstream emissions, yet that do not meet the Environmental Protection Agency's mpg threshold of the regulation.

How could this work?

The city could add an alternative compliance mechanism to its newly approved regulations that allows (but does not require) fleets to use a full, life-cycle global warming analysis to demonstrate compliance with the new rule. With such an alternative compliance mechanism in place, a vehicle with low upstream impacts could comply with the rule, even if its mpg rating does not meet the 25 or 30 mpg threshold (or, as in the case of some vehicles that are retrofitted to run on alternative fuels, no EPA mpg rating at all).

Adding such a mechanism would move the city closer to the ground-breaking approach being proposed in California. In that state, regulators are considering a "low-carbon" approach to regulating fuels and vehicles, rather than regulating mpg or biofuels. The city should share California's goal: to encourage the fuels and vehicles that are the lowest in global warming impact on a life-cycle basis, rather than rely on the more-limited view of the miles-per-gallon of the vehicle, the amount of biofuels used, or the emissions at the tailpipe (all of which are used in various PlaNYC 2030 proposals).
Setting Standards

Lawyers reading this may say, "Wait a minute - the City cannot set its own emission standards."

That's right: only the Environmental Protection Agency and California can set emissions standards for vehicles, and other states can choose to follow them (New York tends to follow the more stringent California standards). But the approach summarized above would not run afoul of the federal restrictions on the city's ability to set vehicle emission standards, because it would not be a mandatory requirement on the fleets. Instead, it would simply be an alternative compliance mechanism that could be used by the fleets or not, as they wish. Thus, such a mechanism should comply with the federal restrictions on the city's ability to regulate vehicle emissions.

The Taxi and Limousine Commission deserves support for its plan to improve the environmental performance of the city's black cars.

Like the yellow cabs, these vehicles drive more miles, consume more fuel, and emit more pollution than other cars on city streets. However, the commission can make a strong plan even stronger by amending the final rule to enable fleets to use life-cycle analyses to unlock the potential of lower-carbon vehicles that could provide effective service in the five boroughs.
Rich Kassel is a senior attorney at the Natural Resources Defense Council, where he focuses on urban air pollution and transportation issues. He also chairs the Tri-State Transportation Campaign, a regional transportation advocacy organization and blogs on a variety of environmental issues on the NRDC switchboard.