Case study (UK): Electric vehicle-to-grid (V2G) charging
- Distribution Network
- Generation and Wholesale Market
- Supply and Retail Market
- Transmission Network
Kaluza is part of a pioneering UK research and development project on one of the world’s largest V2G systems. It uses AI and market signals to automatically charge vehicles at the cheapest and greenest times.
This case study is supplied by Conor Maher-McWilliams, Head of Flexibility at Kaluza (an OVO company).
Electricity grids around the globe are on the cusp of seismic transformation. As energy systems integrate more renewable power and enable the electrification of heat and transport at an accelerating pace, maintaining a balanced, stable grid is becoming increasingly challenging.
A landmark vehicle-to-grid (V2G) programme began in April 2018, a collaboration between OVO Energy, Kaluza, Nissan Motor Company, research consultancy Cenex, and Indra Renewable Technology, and supported by funding from the Office for Low Emission Vehicles (OLEV, now OZEV) and the Department for Business Energy and Industrial Strategy (BEIS). By bringing together expert organisations across energy, transport and infrastructure, the project sought to roll out V2G across UK homes, showcasing the significant economic, environmental and societal value presented by the technology.
V2G charging enables energy to flow bi-directionally - from the grid into an electric car and back again. Connected to Kaluza’s platform, V2G chargers are optimised to import energy when renewable energy is in abundance and then export it back to the grid based on the live-needs of the energy system. Kaluza does this using artificial intelligence (AI) that combines real-time market signals - such as wholesale electricity price feeds, weather and grid data - to automatically charge V2G-connected cars when prices and carbon levels are low, and instruct cars to export energy to the grid when the local grid needs support.
V2G owners get paid for the energy sold back to the grid from their vehicle at a rate of 30p per kWh and use Kaluza’s mobile app to tell the platform when they would like their car ready to drive. This data feeds into Kaluza’s real-time automation engine so that the platform enables the V2G-connected cars to charge using the cheapest energy. This often becomes available at short notice due to, for example, short-term spikes in wind supply. Customers can also see in real-time if their car is importing or exporting energy and how much it is earning them.
Impact and outcomes
Since the beginning of the project, 330 V2G devices have been installed across the UK, and over three million ‘free’ miles made available to customers who exported energy back to the grid during peak times.
Customers in the trial have been able to earn as much as £725 a year without needing to do anything except keep their cars plugged in when they are not in use.
Research has shown V2G has the potential to save £3.5bn per year in areas such as grid infrastructure reinforcement, storage and generation, as a result of the support it offers during periods of increased energy demand.
During the early stages of the coronavirus pandemic, lockdown in the UK also highlighted the potential of V2G. As an unprecedented number of people lived and worked solely at home, the amount of flexible capacity in Kaluza’s V2G portfolio increased by up to 30% compared with pre-lockdown levels.
Such capabilities will become increasingly necessary and valuable as millions more electric cars and heating systems connect to the energy system. By 2030, the UK could have almost 11 million EVs on the road. If 50% of these vehicles were V2G enabled, this would open up 22 TWh of flexible EV discharging capacity per year and could provide ~16GW of daily flexible capacity to the grid.
The V2G rollout project has so far highlighted key areas of development that are needed to support the success of this technology at scale.
- Cost of charging hardware and installation. By the end of the trial, the V2G hardware and installation cost was around £3,700 higher than a smart (monodirectional) charge point. However, with mass production, this cost is expected to decrease rapidly. A cost of around £1,000 would mean the payback period for V2G could comfortably be below five years.
- Vehicle compatibility. In the trial, the only type of compatible EV was a Nissan Leaf, meaning that the pool of customers who were eligible and willing to have V2G hardware installed was relatively small.
- Certifications and localising V2G chargers. We experienced some delays to the V2G hardware gaining the necessary CHAdeMO (‘Charge de Move’) certification, and there were challenges around costs and processes associated with connecting V2G chargers to various distribution networks.
- Market access and value. Exploring monetisation opportunities to scale domestic V2G also provided insight into the challenges that exist and the investment case outlook in the medium-term for technology like V2G. Ancillary market access for domestic flexibility is currently limited due to high entry thresholds, unscalable on-boarding and operational processes at a national level, and early-stage development at local networks level.
While further development is still needed across hardware and installation costs, vehicle compatibility and energy market reform, it is clear that hardware costs are falling markedly and rapidly, and reform in energy markets across the world is accelerating.
Through the trial, this emerging V2G technology has proven its potential for real-world impact and the clear benefits it offers both customers and the grid. For the UK and beyond, it could be a powerful tool helping to unlock a flexible, robust and decarbonised energy system of the future.
- Customers participating in the trial can earn as much as £725 a year without needing to do anything except keep their cars plugged in when they are not in use.
- V2G has the potential to save £3.5bn per year in areas such as grid infrastructure reinforcement and generation, as a result of the support it offers during periods of increased demand.
- By 2030, the UK could have almost 11 million EVs on the road. If 50% of these vehicles were V2G enabled, this would open up 22 TWh of flexible EV discharging capacity per year and could provide ~16GW of daily flexible capacity to the grid.