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Michael G. H. Bell Institute of Transport and Logistics Studies The University of Sydney, Australia |
The pandemic is offering planners and politicians an opportunity to rethink city logistics. Before the pandemic, there had been growing public concern about urban air quality and the contribution made to emissions (and noise) by trucks used in city logistics. This spans trucks used for deliveries to retail outlets, offices, and homes as well as trucks used in the construction industry and refuse collection. The culprit is generally seen to be the diesel engine, because of the greenhouse gases (GHG), nitrogen oxide (NOx), and particulates they emit, along with the noise they produce.
Progress is being made in designing cleaner diesel engines and the Euro standards are providing a lever to help phase out the use of older, more polluting diesel engines in urban areas. The Euro 1 standard of 1992 limited NOx emissions to 9 grams per kilowatt-hour (kWh) and particulates to 0.4 grams per kWh. By 2014, the Euro 6 standard limited NOx emissions to 2 grams per kWh and particulates to 0.02 grams per kWh (National Infrastructure Commission, 2019). In the UK, London introduced a Low Emission Zone in 2008 followed by an Ultra Low Emission Zone (ULEZ) in 2019. All vehicles entering the ULEZ not meeting the Euro 6 emissions standard pay a penalty of GBP100 per day for trucks and GBP12.50 per day for vans and cars.
While cleaner diesel engines clearly help, electric vehicles are seen as the ultimate solution. Electric vehicles have many advantages for city logistics. Firstly, they produce zero emissions at the point of use. Secondly, they are relatively quiet. Thirdly, small electric vans can be operated safely and unobtrusively in shared and pedestrianized spaces.
The use of electric vehicles in city logistics is by no means new. In 1930 the first electric milk float (a small open-sided electric van) was introduced and for 70 years delivered milk in UK cities. Due to changes in cost, diesel vehicles replaced the electric milk floats in 2000. However, StreetScooters (electric vans produced for DHL by Ford of Europe) entered into service in 2016, reflecting improvements in electric vehicles, in particular, battery technology (see https://www.milkandmore.co.uk/electric-pioneers, accessed 6/4/20).
One problem with the use of trucks in city centers is the difficulty in finding free parking spaces or loading zones that are close to the cargo destination. In this respect, cargo bikes are attractive as they can use bike lanes, enter pedestrianized areas and, if parked on street, need less space. A wide range of cargo bikes are available. The Armadillo electric cargo bike from Velove, Sweden, together with the ‘city container’ (sometimes referred to as the ‘meter cube box’) is proving to be a popular alternative in Europe (Erlandsson, 2019).
In some cities, specialized electric vehicles are allowed to operate in pedestrianized areas, which are otherwise closed to vans and trucks. For example, the Cargohopper found in Utrecht, Holland, consists of an electric tractor pulling a series of trailers and is designed for narrow streets and cobbled surfaces (Eltis, 2015).
Many vehicle manufacturers are now active in the electric vehicle market offering a range of vehicle types and sizes, attracted by improvements in battery technology (McKinsey, 2017). Since 1990, battery energy density measured in kWh per kg has more than doubled while the cost measured in US$ per kWh has fallen by more than factor six. Energy density may continue to improve linearly, but cost reductions seem to be leveling out (National Infrastructure Commission, 2019).
Electric propulsion is not only attractive for small goods vehicles. Volvo Trucks has been developing electric trucks with a payload of 12.4 tonnes (Pink, 2019). These vehicles, which are particularly suited to the construction industry and waste collection, are nearly silent with near-zero emissions at the point of use. Battery capacity can be chosen to suit the application and charging opportunities.
One issue with electric vans is their limited range and the time it takes to recharge their batteries. To increase the range of electric vehicles, they can be equipped with hydrogen tanks and fuel cells to convert the hydrogen to electricity. In this way, the range of electric vehicles can be at least doubled and refueling can be performed quickly. However, hydrogen as a fuel for vehicles is not energy efficient. Where hydrogen is generated by electrolysis, the energy consumed by electrolysis, compression of the hydrogen, the fuel cell, the inverter, and the electric motor is such that only about a quarter is left for transporting cargo. Batteries are much more energy efficient. The energy consumed by the charger, the inverter, and the motor leaves about three quarters for transporting cargo. There are technologies other than electrolysis for producing hydrogen, but these are neither energy-efficient nor green as they generate GHG emissions (Baxter, 2020).
In summary, the pandemic is offering an opportunity to change the way city logistics is delivered. Electric vehicles offer a cleaner and greener solution.
References:
Baxter, T (2020) Hydrogen cars won’t overtake electric vehicles because they’re hampered by the laws of science, The Conversation (downloaded from https://theconversation.com/hydrogen-cars-wont-overtake-electric-vehicles-because-theyre-hampered-by-the-laws-of-science-139899, 9/6/20).
Eltis (2015) Utrecht’s sustainable freight transport (The Netherlands). https://www.eltis.org/discover/case-studies/utrechts-sustainable-freight-transport-netherlands, accessed 6/4/20.
Erlandsson, J (2019) Why is the Velove CEO out delivering each Friday? https://www.velove.se/news/why-is-the-velove-ceo-out-delivering-each-friday, accessed 6/4/20.
National Infrastructure Commission (2019) Better Delivery: The challenge for freight. https://www.nic.org.uk/publications/better-delivery-the-challenge-for-freight/, accessed 6/4/20.
Pink, H (2019) Volvo to showcase FE-Electric 6×2 hook-lift rigid at Freight in the City Expo on 6 November. https://motortransport.co.uk/blog/2019/10/29/volvo-to-showcase-fe-electric-6x2-hook-lift-rigid-at-freight-in-the-city-expo-on-6-november/, accessed 6/4/20.