Sustainable Development Goals
Primary SDG: SDG 11 – Sustainable Cities and Communities
Secondary SDGs: SDG 7 – Affordable and Clean Energy; SDG 13 – Climate Action
Background and motivation
The transition from petrol and diesel vehicles to electric vehicles (EVs) is essential for building sustainable, liveable cities with cleaner air and lower greenhouse gas emissions. A typical mid-sized petrol car emits on the order of 150–200 g of CO₂ per kilometre, whereas an electric vehicle powered from the grid can be closer to 50–80 g of CO₂/km on today’s UK electricity mix, and considerably lower as the grid decarbonises. This means that, even when electricity is generated from fossil fuels, EVs can reduce emissions per kilometre by a factor of roughly 2–3 compared with conventional vehicles. When low-carbon generation (renewables, nuclear, high-efficiency combined-cycle plants) is added, the emissions advantage of EVs becomes even more pronounced.
However, large-scale EV adoption creates major challenges for electricity networks in urban areas such as London. A typical UK home might have a peak demand of around 2–5 kW, whereas a common home EV charger operates at about 7 kW, already drawing power comparable to several houses at once. Fast public chargers rated at 50 kW, 150 kW or even 250 kW can briefly consume as much power as 20–125 homes. Distribution networks were never designed on the assumption that every house would draw its maximum power simultaneously; instead they rely on diversity, with households using energy at different times of day. EV charging undermines this assumption and, if unmanaged, can threaten the reliability and affordability of electricity supply in cities.
There are two key issues. First, network capacity: if a significant fraction of households in a neighbourhood each add one or two EVs with 7 kW chargers, the effective peak demand on a local feeder can increase by tens or even hundreds of kilowatts, potentially exceeding the rating of cables and transformers unless costly reinforcement is undertaken. Second, the stochastic nature of EV charging: traditional loads (lighting, heating, industry) follow relatively predictable patterns linked to time of day, temperature, and season, which allows operators to match generation and demand. By contrast, EV charging is triggered by individual travel patterns and battery state of charge. A single 150 kW fast charger can appear on the system like 75 typical houses for an hour at a random time and then disappear. Time-of-use tariffs are currently used to discourage charging at peak times, but if many people shift to night-time charging, the “off-peak” period will no longer be off-peak, and both load profiles and economic models will need to be rethought.
This project therefore sits at the intersection of sustainable transport, energy systems, and urban planning, directly supporting SDG 11 (Sustainable Cities and Communities), with strong links to SDG 7 (Affordable and Clean Energy) and SDG 13 (Climate Action).
Research aims
1. To characterise and model EV charging patterns and how they differ from traditional urban electricity demand.
2. To develop a simple, tractable model of EV charging load that can be integrated into low-voltage network planning and operation.
3. To investigate how different charging behaviours and tariff structures affect network loading, peak demand, and overall utilisation in a city context.
4. To identify strategies (e.g. smart charging, tariff design, managed charging windows) that can support widespread EV adoption in cities without excessive network reinforcement.