Poor Air Quality Forces London's Hand

By Theodora Filis

The British government received a second and final written warning this summer from Europe to clean up London's air or be taken to the European Court of Justice and face fines of up to £300m for being in breach of air quality standards. It is currently waiting for the outcome by the European Commission of a time-extension request.

London’s mayor, Boris Johnson, is under pressure to tackle London's poor air quality, which sees an estimated 4,267 Londoners dying prematurely each year because of long-term exposure to airborne pollution, according to figures released by city hall this year.

A universal fleet of emission-free black cabs within 10 years was outlined by Johnson in his final air quality strategy, published this week. 

Mayor Johnson hopes to encourage London cabbies to switch to low-emission alternatives. The mayor has announced a £1m pot designed to offer a reduction in the purchase price for taxi drivers upgrading to low-emission vehicles and encourage the taxi industry to develop an affordable, workable vehicle in time for the new target.

The new policy in London comes as officials announced plans to install 4,000 new electric vehicle charging stations throughout the UK, calling 2011 the “year of the electric car.”

All new taxis entering the fleet by April 2012 will also have to meet the strictest emission vehicle standards, and eco-driving training for those training to be black-cab drivers will be made mandatory from January of the same year.

All new taxis entering the fleet by 2020 will have to be "affordable zero-emission taxis capable of zero-emission operation", with a 60% improvement in fuel economy required by 2015 from a baseline of 2010.

The targeted action on London's cab fleet is part of a wider set of measures outlined in the mayor's third and final draft on how to clean up London's air.

Johnson said: "London's magnificent cabbies are famous the world over for their top-notch service, but I also want the capital's taxi fleet to match up to the highest environmental standards that a great city like ours deserves.

From 2012 when the world heads to London, we will remove the oldest, dirtiest cabs from our streets. But we are also offering a juicy carrot, with the establishment of a fund to help speed up the introduction of electric black cabs. This forms part of a robust package of long-term measures to progressively clean up London's air."

Hybrid vehicles generally possess both a conventional internal combustion engine and a battery capable of being used to propel the vehicle. The addition of the battery allows the engine to be run more cleanly and economically, substantially lowering vehicle emissions.

An ordinary hybrid such as the well-known Toyota Prius gets all its power from its fuel tank: the battery cannot propel the car any useful distance without help. A few black cabs will be zero-emitters. For the first hour or so each day, anyway. 

Some of the technologies mentioned are, as Mayor Johnson points out "capable of zero tailpipe emission operation". Specifically, plug-in hybrids, battery-only cars, and hydrogen fuel-cell vehicles could be operated without any tailpipe emissions.

Battery-only cars would make terrible taxicabs because a plug-in hybrid can only operate as a zero-emissions vehicle by driving small distances each day. Possible for a typical commuter, but not for a London taxi driver. The first couple of dozen miles driven will be in zero-emission battery mode, and then for the rest of the day, the engine will provide all the energy. The taxi will then become just another hybrid.

Nothing wrong with that, of course, the hybrid has much lower emissions than a typical present-day diesel cab, but the use of the term "zero emission" is at best ignorant and at worst misleading. 

The likeliest technology for the "zero emissions capable" taxi of 2020 is, of course, a plug-in hybrid. General Motors is banking on it with the Volt.