Over the past decade, shared transportation services have grown tremendously in popularity as a result of renewed interest in environmental, energy, and economic concerns, all of which have intensified the need for sustainable solutions. There are several benefits of using shared mobility including, reduced traffic congestion, reduced transportation costs, equitable access and affordable choices for various income groups and it can be used as a first and last mile solution. But is shared mobility truly environmentally sustainable and why is this important?
With almost 30% of global CO2 emissions generated by the transportation industry, it’s important for us to take a closer look at how we are contributing to this output. Theoretically, a reduction in private car ownership means less miles travelled, which should equal a decrease in CO2 emissions – but with so little data on the topic, it’s hard to really quantify how environmentally sustainable our shared mobility services actually are. In this article we will share some of our findings from academic reports and relevant case studies and will discuss:
- The sustainable impact of car sharing
- The sustainable impact of micromobility
- Shared EVs impact on GHG emissions
If you want to read more of movmi’s recent articles on shared mobility, check out our blog page.
HOW ENVIRONMENTALLY SUSTAINABLE IN SHARED MOBILITY?
Whilst it is relatively simple to access information on the size of the transport sector, thanks to the statistics kept by governments and international organizations, the same cannot be said with respect to shared mobility services. For example, Transport Statistics Great Britain and The Committee for Review of Innovative Urban Mobility Services for the Transportation Research Board of the National Academy of Sciences in the United States, do not have any information on shared mobility. Even though shared mobility services are increasing, they have much less developed data and research than other modes of transport, mainly due to a lack of data sharing among companies.
However, we did find some very interesting and relevant academic papers, reports and case studies speaking on the topic of environmental sustainability with regards to shared mobility.
THE IMPACT OF CAR SHARING ON ENVIRONMENTAL SUSTAINABILITY
Case Study: Volvo Car Mobility, Stockholm
Capgemini Invent was commissioned by Volvo Car Mobility, to conduct a study on its sustainability impact. With their extensive database, the company was able to provide the data needed for the intended analysis.
In their report ‘The Sustainability Impact of Car Sharing’, they discuss the findings of a study into the impact of the Volvo Car Mobility service M on the city of Stockholm, examining its impact on both driver behaviour and emission levels, and what value it creates for cities, property developers, companies, and individual customers.
Their report revealed that up to 8 privately owned cars are removed from the streets of Stockholm in exchange for Volvo’s M car service each year. This equates to around 4,515 fewer cars based on the company’s current vehicle fleet size and a reduction of 8,200 tons of CO2 from tailpipe emissions. This is a 3.2 million litre reduction in fuel consumption and 3.8 million litres in water savings (due to less car washes.)
Furthermore, up to 41,300 tons of CO2 emissions could potentially be avoided from fewer cars being produced. This would also free up an area of 56,400m2 previously used for parking that could be replaced with green infrastructure or housing.
SHARED MOBILITY CHANGING TRAVEL PATTERNS & BEHAVIOURS
It is difficult to determine the percentage of trips that could realistically be replaced with shared mobility services in any city. However, as cited by Georgina Santos from the School of Geography and Planning, Cardiff University, a number of studies have investigated how and to what extent mobility sharing programs can change urban travel patterns.
In Germany, 12% of respondents of a car sharing users survey, reported giving up a car in their households (the authors estimate that the total vehicle miles travelled by the households that had given up a car was on average 50% lower than the total vehicle miles travelled by the households that had not), 40% reported they had abstained from buying a car, and 27% reported they were considering giving up a car.A model of the effects of full-scale implementation of shared mobility in the whole of the Lisbon metropolitan area (assuming a 100% replacement of all car and bus trips by new shared modes, rail-based public transport, and walking) found that total vehicle miles travelled at peak times would be reduced by 55%, and CO2 emissions would be reduced by 62%. A more realistic exercise for Helsinki, assuming that only 20% of car and taxi trips were replaced with shared mobility, found that vehicle miles travelled would go down by 7%, CO2 emissions would go down by 2%, and congestion would go down by 13%.
THE IMPACT OF CAR SHARING ON MOBILITY & CO2 EMISSIONS
In 2015, PBL created a study to understand the impact of car sharing on mobility and CO2 emissions in the Netherlands. The study consisted of a survey of 363 car sharers selected from a representative panel of TNS-NIPO to. To answer the question about the impact of car sharing on mobility and the environment, they then compared situations before and after car sharing as well as a hypothetical counterfactual.
The respondent car sharers, on average, drove around 9,100 kilometres per year by car, before they started car sharing. By 2014, they were driving considerably fewer kilometres, namely around 7,500 per year, a difference of 1,600 kilometres, mostly because owners who disposed of their privately owned car began to drive far less when car sharing.
This resulted in a reduction of 250 kilograms of CO2. However, for this number to be realistic, it would mean that the kilometres not driven in shared cars (1,600km) would have needed to be travelled using more environmentally friendly modes of transport, or not have been travelled at all. By choosing the car over other modes of transport, car sharers in 2014 cause an additional 160 kilograms in CO2 emissions.
When we take both the number of car kilometres driven and the change in mode of transport into account, the reduced car use of car sharers yields an annual CO2 reduction of 90 kilograms on average. However, car ownership also involves CO2 emissions, as vehicle manufacturing and demolition require resources and energy, as well. Taking this into account as well, the decline in car ownership has led to an additional reduction in CO2 emissions of 85 to 175 kilograms per year, per household. Using a shared car has led to an average reduction of between 175 and 265 kilograms in CO2 per respondent. This equals a reduction of around 8% to 13% in emissions related to car ownership and car use.
IS MICROMOBILITY ENVIRONMENTALLY SUSTAINABLE
“Each mile someone rides on a bike-share bike instead of driving a car means about one pound of carbon dioxide is kept out of the atmosphere,” – Dr. Susan Shaheen.
The problem is that we don’t know for sure how many people ride a bike as an alternative to driving a car and that the data varies greatly from city to city. However, there are a few case studies highlighting the environmental benefits of current bike sharing systems. For example, in Denver, Colorado, 41% of B-Cycle bike trips replaced car trips, and the entire program is estimated to have avoided more than 1 million pounds of CO2 emissions.
B-Cycle, the company that designs the bike-sharing systems used in Denver and more than 20 other cities across the country, says that on all of its systems combined, 2.1 million bike trips covering 4.5 million miles have been made on its bicycles since 2010, all of which have offset more than 2,948 metric tons of CO2 emissions and saved more than 330,000 gallons of gasoline.
Also, research estimates that China had a ridership of 20.3 million bike-share users in 2016. Using big data analysis, Yongping Zhang of Nankai University and Zhifu Mi of University College London, found that in 2016, bike sharing in Shanghai reduced the consumption of petrol by 8,358 tonnes. Greenhouse gases like nitrogen oxide were reduced by 64 tonnes and carbon dioxide by 25,240 tonnes.
If we want to look at how environmentally sustainable shared e-scooters are, it’s important to look at the four main phases of its lifecycle. According to one study published by North Carolina State University, e-scooters emit about 202 g of CO2 per km and per passenger over their entire life cycle which is about as much as a conventional car and 3.5 times more than an electric car.
One of the main reasons for this is linked to the vehicle’s production where 50% of the carbon impact comes from. The second biggest problem is charging electric scooters. Trucks that emit CO2 are needed to collect each dockless scooter in order for them to be charged overnight. 43% of greenhouse gas emissions are linked to recharging, which means that the production of energy represents a little less than 5% of the GHG balance of electric scooters.
Researchers noted that the main way to reduce the environmental impact of scooters is to extend their lifespan, which is currently at around 1 year. This short lifespan means they’re only used for a few hundred kilometers and so the negative impact of battery production isn’t negated. By focusing on manufacturing and creating more durable vehicles that will last longer, e-scooters could significantly cut their contribution to CO2 emissions globally and become more much environmentally sustainable.
THE SUSTAINABLE IMPACT OF EVS ON GHG EMISSIONS
Comparisons between electric vehicles and conventional vehicles are quite complex. However, as a whole, EVs are responsible for considerably less emissions over their lifetime than conventional internal combustion engines. However, in countries with coal-intensive electricity generation, the benefits of EVs are smaller and they can have similar lifetime emissions to the most efficient conventional vehicles – such as hybrid-electric models. That being said, as countries decarbonise electricity generation to meet their climate targets, driving emissions will fall for existing EVs and manufacturing emissions will fall for new EVs.
It also has to be noted that there are uncertainties around the emissions associated with electric vehicle battery production. Like with most things, as battery prices fall and vehicle manufacturers start including larger batteries with longer driving ranges, battery production emissions can have a larger impact on the climate benefits of electric vehicles.
In a study, analyzing the effects of car sharing services on the reduction of greenhouse gas (GHG) emissions by Jiyeon Jung and Yoonmo Koo, they calculated a reduction in total GHG emissions resulting from an increased probability of choosing EV car sharing in the future.
They surmised that with an increase in EV infrastructure, more individuals will be willing to drive electric car sharing vehicles. If the number of EV charging stations increased to approximately 50% that of gasoline stations, the probability of choosing electric car sharing vehicles increased. Therefore, GHG emissions from vehicle use could be reduced to 1013.19 tCO2e/day. This represents an emissions reduction of 1796.64 tCO2e per day (i.e., 655,773.6 tCO2e per year).
If electric vehicle infrastructure was expanded, their analysis shows that total GHG emissions could be reduced to zero, compared to the current car sharing market situation. Thus, rather than supporting car sharing per se, a proliferation of fuel-efficient EV car sharing vehicles is a more effective means of reducing GHG emissions through car sharing services.
Even though there is limited data with regards to shared mobility services and their effect on the environment, it’s clear to see from selected studies, that with an uptick in the usage of sharing services, the number of privately owned vehicle trips decreases, which ultimately reduces the level of GHG emissions. However, we need to start building and implementing more charging infrastructure in our cities, so that we can launch more shared electric vehicles which will significantly impact our contribution to CO2 emissions. We also need to focus on decarbonising electricity generation for these vehicles to be truly environmentally sustainable and take a hard look at our battery manufacturing processes and how it can be improved to help me our climate goals.