Urban Transformation

3 surprising reasons why cities are struggling to slash emissions

cities An e-scooter user logs on to an app to rent a scooter from Bird in Munich, Germany, September 5, 2021. Picture taken September 5, 2021.

We need a standardised approach for accounting and reporting the carbon emission intensity of urban mobility in cities. Image: REUTERS/Nick Carey.

Adam Gromis
Public Policy Manager, Sustainability & Environmental Impact, Uber Technologies
Maya Ben Dror
Industry Manager, Automotive and New Mobility & Advanced Manufacturing, World Economic Forum Geneva
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  • Cities account for 50% of global emissions and transport emissions from travel and deliveries are growing.
  • Mobility service providers are capturing and sharing emissions data, and researchers have developed methodologies and emission factors for cities.
  • New mobility integrations can help make inroads into slashing emissions in cities but they need to be based on real-world data.

About 18% of global energy emissions can be attributed to road vehicles, of which 60% come from passenger vehicles. Moreover, these emissions are on the rise, and half of them originate in city trips. Through a combination of existing solutions, trip emissions can be reduced to zero or near-zero levels at the tailpipe, while serving an urban mobility demand.

“Cities are leading the way in taking action to reduce emissions from transport. The unprecedented choice now available in urban mobility can help meet the needs of citizens and businesses, while also advancing climate goals. Old truths about transportation planning are no longer valid. We need high quality, fresh and comparable data to make informed choices about promotion and regulation.” Daniel Firth, Programme Director, Transport and Urban Planning, C40 Cities.

Still, tackling city mobility emissions means grappling with many surprising challenges and fast evolving realities. Understanding these challenges can better position city leaders to tackle growing city mobility emissions head on. It will also help a sustainable mobility ecosystem grow in cities, contributing to their societal, environmental and economic goals.

Here are three challenges that leaders must understand to slash mobility emissions in their city.

1. Simple city trips aren’t that simple

A city trip often does not start when a rider enters a vehicle door and ends when the rider steps out of the same door. It increasingly looks more like a series of trips combined into one travel need. An example of this would be to compare the carbon intensity of a commute involving a ride-share to a park and ride train station in the suburbs versus taking an express bus into the city with a bicycle-sharing scheme to cover the first or last mile, incorporating direct and indirect emissions related to the operation of the mobility assets.

What’s needed next: While the cleanest trips for cities to prioritise are non-motorized trips, such as walking or cycling, that is not always feasible, efficient or safe for citizens and visitors. Cities need to understand the full scope of transportation operations and potential impact of potential alternatives. Cities need to look into the truly messy carbon footprint of travel and deliveries that occur in its authoritative jurisdiction. Only then, will they be able to collect and combine the pieces of information needed for setting impactful policies. For instance, by acknowledging the full range of transport options any one trip requires, cities can have a better sense of its full carbon intensity. From there, they can incentivize and disincentivize trips with carbon intensity in mind to encourage the right types of operations and behaviours – bringing long-lasting benefits to health, the economy and climate.

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2. There’s no standard way to measure progress

There’s currently no standardised, consistent and comparable approach for accounting and reporting on the carbon emission intensity of urban mobility. This makes it difficult for users, mobility operators, service providers and cities to truly understand and compare carbon emissions and reductions across all mobility modes, whether used individually or in combination with complete a trip. However, some precedents do exist, for instance fuel efficiency is often used as an intensity metric to understand the carbon impact per mile (or kilometre) of petrol vehicles. However, in urban areas, with a vibrant landscape of current and emerging urban mobility modes, the fuel efficiency metric holds limited relevance to compare between modes.

Still, standard metrics can be powerful. Many shared micromobility operators have started reporting in recent years on carbon emissions per passenger kilometre, and this reporting incentivized business actions useful to both the financial and environmental performance of these companies. TIER has been tracking the carbon emission intensity per passenger kilometres (CO2/pKm) of its e-scooters for the past few years. This has resulted in design improvements. For instance, instead of collecting scooters for maintenance, maintenance is provided on site using an electric cargo bike service.

This new approach not only slashed operating emissions which go into the footprint of each kilometre travelled on scooters, but also improved the financial performance of the company. Altogether, these changes led to a 60% reduction in CO2/pKm. Voi, a shared e-scooter provider, has been tracking well-to-wheel CO2/pKm for its e-scooters and is implementing a variety of measures to reduce their footprint, including a 400% increase in scooter lifespan.

“The micromobility industry has made huge strides in terms of sustainability,” said Fredik Hjelm, CEO and Co-Founder at Voi. “To bring sustainability to the next level and democratise these improvements across the sector, standardised emission reporting practises are needed to ensure we compare apples to apples and cities can select the most sustainable services.”

What’s needed next: Measuring passenger carbon intensity – emissions per passenger distance – would be a more meaningful metric to understand emission intensity-related performance of different mobility modes. It suggests that relevant mobility operators, service providers and cities should agree on the use of similar metrics and methodologies to allow for meaningful comparisons between operators and providers and modes.

3. Policy approaches aren't shifting fast enough

Where they do exist, electric vehicle (EV) policies have been largely written for private vehicle owners and not shared-use applications. That’s a missed opportunity. Although commercial shared-use operators like taxi and ridehail tend to account for only a few percent of urban travel mileage, a shared-use driver averages three times the annual mileage of private car user and therefore three times the emissions savings opportunity when they go electric. Recent emissions reporting by ride-hailing companies reveals increased EV uptake by drivers where policy environments exist like zero emission areas, where tailpipe emitting vehicles are restricted, and clean air plans, where the city introduced restrictions to limit air pollutants.

In London, more than 3.5 million trips were taken in fully EVs by drivers using the Uber app in the first half of 2021, and by year end Uber’s platform hosted eight times greater EV use than the general vehicle population. Uber attributes much of the outsized, early success of EV uptake in London to the city’s world-leading congestion and emissions pricing schemes. Following the implementation of a congestion charge zone in 2003, London’s traffic decreased by 15% and travel time decreased by 30%. A recent report by the city calls for a 27% reduction this decade, alongside a more rapid shift away from fossil fuel vehicles towards active transport, public transport and cleaner vehicles.

What’s needed next: Research from the International Council on Clean Transportation shows that policy needs to account for a combination of incentives. This combination could include restricted zoning access, preferential lane access, subsidies for vehicle replacement, charging and battery swapping infrastructure investments, for addressing the various barriers to high mileage vehicle transition to EVs. Policy environments can also pave the way for a range of other solutions, including dedicated mobility hubs, where a variety of mobility vehicles are available for hire or ridership. Such policy actions should be tailored per city, and their usefulness will be validated only if we continue to measure and report.

What can leaders do now?

We already possess many of the solutions needed to shift to zero tailpipe emissions, shared and automated travel and delivery, and have coalitions for synchronized action. What’s needed next is for leaders to apply best practises to maximise these technologies and approaches.

Some efforts are already underway. The European Commission, for example, recently released new guidance calling for cities to consider incentives to electrify high-mileage drivers as the region is battling to meet its carbon reduction goals. Cities now need to act, in Europe, North America, Asia, and beyond.

“Climate is a team sport. That’s why Uber is proud to work with peers, advocates and experts from the GNMC to offer these Principles for Reporting Emissions from Urban Mobility. The road to zero emissions requires transparency and being accountable for progress year after year, and the journey can only be made together.” Adam Gromis, Global Lead for Sustainability Policy, Uber

Additionally, public and private sector members of the World Economic Forum’s Global New Mobility Coalition recently came together to develop the Principles for Reporting Emissions from Urban Mobility. This executive paper was designed to inspire collaborative public-private action for employing real-world emissions data in decision making for cities.

Principles for Reporting Emissions from Urban Mobility. Source: The World Economic Forum.
Principles for Reporting Emissions from Urban Mobility. Source: The World Economic Forum.

“In order to avoid the most harmful impacts of climate change, we need to accurately and rapidly reduce carbon emissions from transportation.” said Robert Grant, SVP, Government Affairs & Social Impact at Cruise. “The Principles for Reporting Emissions from Urban Mobility provide shared mobility operators like Cruise the vision to truly start reducing transportation emissions globally, mile by mile.”

“We have the scale to support the transformation of the mobility system in Indonesia and this region, to one that is more sustainable and accessible for all. We have a responsibility to our drivers, users and everyone connected to our ecosystem, and these principles ensure we are reporting our shift towards Zero Emissions by 2030 in a credible, consistent and meaningful way.” Kevin Aluwi, CEO, Gojek.

A highly competitive business environment has inspired much innovation in micromobility operations and supportive urban design. These fast improvements are just the tip of the iceberg when it comes to transforming mobility. Enabling policy environments can pave the way for even more change ahead.

The Principles for Reporting Emissions from Urban Mobility are a joint effort of the members of the World Economic Forum’s Global New Mobility Coalition (GNMC), a network of 200+ globally renowned experts, NGOs and companies.

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Urban TransformationClimate Action
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