Holistic Fleet Electrification
Fleets are rapidly electrifying and new electric vehicles (EVs), charging systems and start-ups are appearing on the scene on an almost weekly basis. In short, the sector is booming. But apart from scaling, what is next for the industry?
When working with our clients and collaborators in the UK, a trend we are noticing is an emerging need for better integrated, smarter and more holistic systems. Local authorities are tasked with thinking about many moving parts, from electrifying their fleets and installing public charging points, to addressing broader net-zero requirements linked to their street lighting or housing management activities. The market is providing solutions to all of the above one-by-one, but siloed delivery is expensive and inefficient. Allocating a charging point and necessary grid capacity for each EV in each fleet – as we are doing today- will mean an unnecessary overdesign of the network, leaving plenty of unused charging equipment and an oversized power supply capability in the ground. To electrify all vehicles in the country and reach net-zero targets, it seems necessary to think more strategically about how we create a sustainable and efficient EV future.
Many of our partners are local authorities who have the scale and remit to consider the implications of the above. So, we at DG Cities decided to develop two alternative approaches to EV charging that better align with the more sustainable and efficient future we hope to see.
Could RCVs power our cities?
The UK currently has around 13,000 refuse collection vehicles (RCVs), making daily rounds in the neighbourhoods that they serve to collect the rubbish left outside the 23 million homes we live in. Apart from a handful of electric RCVs operating, all of these large vehicles are running on diesel, contributing significantly to pollution and CO2 emissions. Just to put it into context, the CO2 emissions in a year from a fleet of 50 RCVs is similar to emissions from 500 small vans. However, we think in the next phase of their evolution they could be part of a holistic solution against climate change.
Electric refuse collection vehicles have very large batteries (~300kWh), using approximately half of this during their operational day. This means that once the vehicles’ shifts are finished around 3-5pm and they park at their depot, there is a huge storage capacity available for other use. This capacity could total 2.5GWh nationwide (assuming 150kWh available from all 14,000 vehicles) and could be released back to the grid through vehicle-to-grid charging points. Considering a constant release during the peak electricity demand times of 5-10pm, this could add 0.5GWh to the national supply. 0.5GWh is 10% of the ~5GWh jump the network experiences at peak times as people get home, start cooking, washing and turning on their TVs. It’s also equivalent to the capacity of about 50 large wind turbines.
Not only would this supply be quite significant, it is critically located at the right places. Bin lorries operate where people live, hence they could provide supply without the requirement of transporting it huge distances. The simple ability to draw on this reliable supply could help the grid to be balanced locally.
Why would fleets do this?
Apart from the positive environmental impacts, this system could generate money for fleets. If we assume a 10p average difference between peak energy costs, when the fleet could be selling electricity to the grid, and the off-peak costs at night and weekends, when RCVs would be charging, for a vehicle fleet of 50 electric RCVs, it could be making fleet managers £750 per day (or nearly £200,000 a year). And this would still have all vehicles charged up by the morning. Meanwhile today running the same routes on a diesel fleet costs £1,800 per day, just on fuel costs.
This approach could be integrated with sustainable housing energy projects, where the vehicle batteries can be used to directly power buildings nearby. This model could reduce the need for a large back-up power supply during peak times, providing a better business case for alternative energy generation options, i.e., solar panels or heat pumps to power the homes consistently.
Whilst a refuse collection vehicle might need a charge every day, many of the smaller fleet vehicles do not. In our work analysing the fleet of a London borough, we understood that the average mileage was quite low with 90% of all daily journeys being under 50 miles (75 km). With smart charging and allocating vehicles to chargers only when needed, we could show that one charger for every four vehicles is sufficient to keep the fleet running. This approach can significantly reduce the required charging capacity at the depot, making it cheaper and more feasible for an electric transition.
If we want to further reduce depot-based charging, we can analyse where vehicles are during the day, whether they have regular stops and if they are near to specific locations to see if off-depot charging could be an option. Working with our partners at Imperial College London, we identified a total of 62 sites where the borough’s fleet vehicles stopped regularly (over 500 times in a year) for over 30 minutes at a time. Installing EV charging points at these locations would support the council’s fleet, further reducing the number of vehicles that need to be charged at the depots. From the 550 vehicles, there were 86 (15%) that visited one of the 62 sites over 300 times in a year, giving an opportunity for daily top-up charge. As vehicles only travel a maximum of ~300kms (186 miles) a week, 1-1.5 full charge a week is sufficient, which takes about 1.5 hours at a fast charger, but not more than 10 hours even at slow chargers. Based on our survey with drivers, this amount of charging time is achievable without disrupting operations, as drivers would be delivering tasks, having lunch, picking up supplies, etc., all whilst their vehicle is parked.
Although a 15% further reduction in charging points might not seem significant at first glance, we wanted to be conservative with this approach to ensure that operations are not disrupted. Based on future trial work, we believe that we could double the vehicles using this charging approach, extending it to 1/3 of the fleet.
Further, this approach only considered the council’s fleet. In the next phase of our work, we are looking to combine the fleet’s requirements with the public EV charging deployment of the borough to create multi-use charging points; ones that can be used by the public most of the day but also reservable by the council fleet. We are also looking to extend this approach to other fleets operating in the borough, who are looking to electrify but might not have the right scale or necessary investment to install their own charging infrastructure, or if they might be considering relocating from their existing depot in the near future. Blue light service fleets (police, fire brigade, ambulance), delivery vehicles, white vans, taxis, etc. all experience the same pressures to electrify their vehicles; meaning that a collaboration that creates a distributed charging network that can support all of them would be beneficial and a viable option for this borough, or indeed any other city.
At DG Cities we work with our clients to identify such innovative and holistic solutions to help them electrify their fleets. By knowing how our clients operate, we can always find practical steps to ensure we can achieve tangible results. For us, the path towards a zero-carbon future is about more than just eliminating fossil fuels; it encompasses smart thinking to better use available assets, move beyond siloed thinking and have a real, material impact at multiple levels. If we don’t follow this approach, electrification might become prohibitively expensive and not fully sustainable.
DG Cities’ Head of Delivery, Balázs Csuvár.