Nottingham City Council in the UK is part of a European project that will test a single control platform for managing local energy generation, storage and vehicle-to-grid (V2G) charging to reduce energy costs.

The pilot, which is one of four across north-west Europe, will start in early 2019. Cenex, a not-for-profit technology centre focused on the integration of electric vehicles (EVs), clean generation and energy storage, is also a key partner across all pilots.

Across Europe cities are investing in renewables and charging infrastructure for electric vehicles (EVs). But as these are usually distinct endeavours, the control systems for energy generation, usage, energy storage and EV charging are separate from each other, resulting in missed opportunities to align clean, competitive renewable electricity sources with EV charging.

In the CleanMobilEnergy initiative Nottingham and the three other cities will host trials for the software platform. Interreg North-West Europe (NWE), a European Territorial Cooperation Programme set up by the European Commission, is providing funding support for the project, including the individual city pilots.

The software controls will enable smart integration of different hardware component blocks, such as solar PV, energy storage and bidirectional V2G chargers through interoperability based on open standards for analysis and data flow tools.

Each city will provide a different use case for the iEMS, which will be sought by the partners through an open procurement process in the coming months.


Forward thinking

Nottingham, already forward thinking among UK councils when it comes to provision of public EV charging infrastructure, was asked to take part by CleanMobilEnergy’s lead partner, Gemeente Arnhem in the Netherlands. The two other city pilots will be in London, UK and Schwäbisch Gmünd, in Germany.

The thrust of Nottingham’s project is to show how the city council can reduce its energy costs, which could potentially increase in future as fleets switch to EVs, as the council facilitates charging at work.

An 88kW rooftop solar PV array will be installed on one of the council’s buildings that will be connected to a 378kW/676kWh

Aerial view of Nottingham City Council’s plans to install solar PV, birectional EV chargers and battery as part of the CleanMobilEnergy pilot (Courtesy of Cenex)

battery. Bidirectional chargers for as many as 40 EVs, each with a 30kWh battery pack, will provide an additional 1.2MWh storage resource.

In the coming months, procurement of the PV, storage system, chargers and other components will start, in time for January 2019 when the system will need to be installed by. The project will run until March 2021.

Traditionally the various departments within Nottingham City Council have managed their own fuel budgets. As more of the fleet switches over to electricity-powered EVs, fiscal responsibility for their running costs will roll into the council’s energy services department, increasing its energy bill.

While some of this spend can be charged back to the different departments the project will demonstrate significant reductions in the cost of energy associated with EV charging.


Solar self-consumption for EV charging

Using solar generated electricity and surplus stored in the battery will allow onsite clean energy to provide electricity for vehicle charging. The system will be specified to provide other functions and services as markets develop.

The V2G chargers will allow the cars, when parked, to participate in grid balancing services earning revenues that can be set off against energy costs.

Impact of EVs on the grid with and without bidirectional charging (Courtesy of Cenex)

V2G expertise

Cenex has developed expertise in the use of bidirectional chargers, which allow electric cars to provide energy support to buildings and also the grid, reducing peak demand and providing balancing services to generate additional revenue.

“If we can show that the council’s internal energy costs for EV charging can be minimised then it means more money for frontline services, so it is an important project from that perspective,” says Katie Greenhalgh, senior energy projects officer at Nottingham City Council.

As the project progresses and information is disseminated it will serve as a valuable example for other councils across the UK to learn from and adopt.

According to Greenhalgh the project will also give the council first hand experience of how a large-scale behind the meter battery can be deployed.

“We’ve got a couple of small batteries installed at the council and although we’ve wanted to install a larger a battery such an investment has not been possible until joining the CleanEnergyMobil project. So we are excited about seeing what this technology can do with the view to future deployments to optimise low carbon generation and reduce energy costs,” she says.