Author:
Dunstan Power, ByteSnap Design and Versinetic
Date
12/29/2020
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Figure 1: VIGIL Project 1 - Charge post charging vehicle at Aston University test site
Enabling EVs to return energy to the power grid when parked and plugged for charging, will increase grid resilience, allow for better exploitation of renewable sources and lower the cost of ownership for EV owners – leading to new business opportunities and clear advantages for EV users and energy consumers.
VIGIL was backed by Innovate UK, the Office for Low Emission Vehicles (OLEV) and the Department for Business Energy and Industrial Strategy (BEIS). £15 million of funding was available for a number of V2G projects and VIGIL secured some of that budget. The project was delivered by a consortium of partners: ByteSnap Design, EBRI at Aston University, Nortech and Grid Edge.
Challenge
The VIGIL project was set up to address issues around local power distribution as more EVs appear on the road, and especially to:
1. Avoid substation overload – imagine the scenario, where the UK population predominantly drives EVs. We arrive home from work and all start charging; this would lead to pressure on the grid. A successful VIGIL project was to demonstrate how EVs could give and take energy from buildings.
2. Use an EV as an energy storage unit – VIGIL needed to prove that car batteries can be used to store renewable energy, such as wind power. Energy stored travels with the car and any excess could be discharged to buildings.
VIGIL also looked to linking data from a set of electric vehicles right through to the grid to a smart building energy management system (BEMS) to optimise power used and minimise infrastructure costs. For instance, at a shopping centre, cars within the surrounding car park can balance power to the centre itself during the day, reducing the peaks and troughs on the local substations.
Solution
VIGIL is ground-breaking; it proved that expensive grid upgrades are not necessary to benefit from the V2G technology available within some EVs, such as the Nissan Leaf, and it can remove headaches from future planning around large scale EV parking at commercial premises - giving more confidence that this development in society provides a solution, rather than a problem.
The off-vehicle system controls how, when and the rate at which electric vehicle batteries are charged/discharged with respect to local substation constraints and EV/building energy requirements.
The VIGIL-ANM (Active Network Management) is responsible for managing the distribution network constraints. VIGIL-ANM equipment comprises a substation monitor and the Envoy-ANM controller communicating with Nortech’s iHost platform. The iHost platform hosts the VIGIL-ANM engine that determines the substation’s available capacity based on real-time network conditions.
The V2G/BEMS controller comprises the Grid Edge monitoring and control panel. This securely connects to the building’s management and energy monitoring systems. The data is used to optimise the dispatch of assets in the buildings and the charge/discharge strategy of the V2G units such that the grid constraints are met and building performance and service are maintained as far as possible.
Embedded electronics consultancy ByteSnap Design developed a V2G OCPP EVSE smart charge point communications controller which provides interoperability and control of any EV charger via the OCPP 2.0 standard. The controller reduces latency and improves system robustness by allowing direct control via the building management system. ByteSnap also built a communications adaptor, leveraging its expertise in EV charge post design. The communications adaptor safeguards the flexibility and interoperability of the VIGIL platform with V2G charge-points of varying manufacturers.
The ByteSnap controller, named MantaRay, can be adapted for controlling many other V2G or smart chargers with different communication standard providing complete local control. ByteSnap also created a V2G mobile application which is being delivered together with an optimised building management system.
As part of the project, the team at Aston University investigated a prediction model for EV battery-life performance considering factors such as State-of-Charge, State-of-Health, Charging-speed, Depth-of-Discharge, and remaining energy capacity. Power quality issues for different V2G/network scenarios was also investigated with research findings disseminated to industry and academia.The team published its research outcome at IET International Conference on Renewable Power Generation 2019. The paper was awarded “Conference Best Paper” by the conference committee.
In May 2019, the demonstrator was first installed at Aston University’s EBRI centre, which acts as the smart building within the demonstration. A further threeV2G charge posts and harmonic meters were added at Aston site and in 2020 were fully commissioned and ready for service.
Following testing of the end-to-end communications, there is now a fully operational system collecting data – this means communications from car to charge point to the DNO (distributed network operator) controlling distribution of electricity.
Today, a driver can plug a car in and use the mobile app to stop and start the charging process and change demand on the system.The new communications system provides the DNO with network control and the V2G/EV owners with charging control, avoiding the requirement of a third party.
The project (including the V2G mobile app) has been trialled on several EVs.
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Figure 2: VIGIL Project 2-1 - VIGIL charge post
Benefits
The main purpose of the project has been achieved; to analyse the effects of V2G on a vehicle’s battery and learn what strategies work for load balancing that avoids draining the EV’s battery, whilst satisfying the EV owners demand to have enough energy in their battery for their use when they want it. By using local EVs as a form of energy storage, electric vehicle drivers can avoid costly upgrades and disruption to the energy network.
VIGIL supports two-way communication of information and charge-scheduling, allowing two-way trust to be established, to ensure DNO's confidence in a secured network and EV/charge-point owner in satisfactorily performing equipment/EV.
There are four V2G chargersat Aston University equating to 40kW of transferable power. The VIGIL platform allows this energy stored within the attached cars to offset power used within the smart building.
As a result of the success of the project, ByteSnap Design has launched a dedicated EV charging division called Versinetic. The new firm is built from the VIGIL team and those that have worked on other charging projects, including the London Olympics. Through a set of flexible products and services called Charging Blox, Versinetic can accelerate an EV charging project’s time-to-market.
