London 2012 Fleet Infrastructure Project - EDF Energy

The London 2012 Olympic and Paralympic Games were the first to be truly sustainable, and as part of this commitment LOCOG pioneered the inclusion of Electric Vehicles into the Games-time fleet.

As the official automotive partner to the London 2012 Olympic and Paralympic Games, BMW Group brought more than 4,000 low emissions vehicles to London for use at Games time. Included in the fleet were 200 full electric cars, represented by 40 converted MINI Es and 160 ActiveEs; the electric 1-Series coupe.

Five high profile sites at and around London Games venues were chosen by LOCOG as vehicle re-charging points, ranging from existing underground car parks to bespoke new builds. A recharging infrastructure was required at all these sites to accommodate concurrent recharging of up to 30 electric cars at any one time, in each of the venues.

The Team
Realising this vision required a number of specialists from several industries to come together to leverage their individual knowledge and skills in this emerging market; from energy to automotive to local Government, with cooperation across a broad network of stakeholders key to delivering a seamless Olympic experience for Games time whilst ensuring a legacy EV framework for future use.

The project partners, EDF Energy, BMW and GE, with the support of Charge Point Services and in partnership with Transport for London and LOCOG delivered 114 charge points at the 5 chosen locations to support the use of the 200 EVs which were used as venue transport for athletes, VIPs and staff.

EDF Energy provided technical expertise in power quality management and charge point infrastructure. 

Technical considerations
The project had a number of requirements and constraints:

• Unique usage patterns of the fleet – unpredictable journeys of a high daily mileage with limited availability for recharging
• Broad range of locations and site requirements.
• Charge point hardware had to be fully compliant with the IEC and IET standards.

Supply Capacity
The pattern of Olympic fleet operations was likely to require all charge points to be in use at full capacity at the same time. Therefore, supply capacity planning and load diversity were key considerations of the technical planning.

Today’s EV infrastructure in the UK is typically a mixture of ‘slow’ 3kW (13A), and ‘fast’ 7kW (32A) charge points in low density and at low utilisation, delivering concurrent charging loads of less than 100A per site. The project installed between 12 and 30 charge points of 7kW, 32A capacity at each site, and tested the installed infrastructure at maximum utilisation, delivering concurrent charging loads of over 900A. This load volume represents projected scenarios of destination and fleet recharging likely to be typical from 2020 onwards.*

Location
A key consideration for any infrastructure design is distance between charge points and the electrical supply intake.  In many of the Olympic installations, charge points were located some distance (up to 200 meters) from the electrical supply intake. This meant that close attention had to be paid to voltage drop within the installation and hence suitable cable sizing installed.

Earthing
Earthing can be a challenge in EV infrastructure installations. Extraneous metal work near the Olympic recharging infrastructure, such as crash barriers and hand rails – where contact could be made when charging a vehicle - were bonded into the electrical system, reducing the risk of a difference in potential between the vehicle and the buildings’ metal work.

Harmonics
Close attention also had to be paid to power quality impacts on both the local site’s electrical infrastructure and the grid network. It’s a known phenomenon that EV charging, in common with other forms of electrical control and switching systems, can generate harmonic and other impairments to the electrical supply, which if not managed effectively can cause disturbances within the site’s installation and back into the grid network.

EDF Energy carried out design studies to calculate expected levels of harmonic distortion voltage unbalance and other impairments due to EV charging under the full range of operating conditions. These design studies were then validated by the comprehensive testing programme undertaken at each site before Games mobilisation.

Testing
The programme of on-site tests was structured into a series of carefully conducted stages including:

• Progressive connection of EV charging load, increasing up to the full installed capacity at the site, in controlled increments
• A substantial period of steady-stage charging at full load
• Interruption and restoration of the electrical supply to the fully loaded charging infrastructure (simulating loss and recovery of power to the site.) – this included interruptions of different duration
• Completion of the charge cycle, monitoring the progressive reduction in load as cars reached their full charge.
• Connection of charging load to one supply phase only with no charging load on other phases (worst-case unbalance conditions)
• Connection of different mixes of the 2 vehicle variants used in the Olympic fleet
• Site load was taken into consideration and testing was carried out during the day when the site was under normal load and repeated at night with minimal load.

As predicated in the EDF Energy modelling, test results proved highly positive. The technical design ensured acceptable margins of power availability and voltage conditions were maintained and the infrastructure was not unduly stressed, even when running at full capacity. Power quality disturbances, though measurable, were comfortably within regulatory limits and not specific treatment measures were needed (although the installation design had made provisions to facilitate deployment of harmonic filtering and other techniques had these been required).

Successful Recharging at Scale
Successful Games time recharging was achieved without incident, enabling London 2012 to run a low carbon fleet incorporating EVs. The project confirmed that large scale concurrent vehicle fast charging can be accommodated given the right electrical solution.

The charge points have since been accepted into the Source London Network, and are open to Source London members where car parks have been returned to public use. The legacy of the project is much broader that just the physical infrastructure. Games time and test data captured by the Project, alongside the technical expertise and insight gained, is being shared with industry stakeholders to support the development of the EV recharging market through shaping future infrastructure strategies and ensuring safe and reliable recharging.

A positive legacy project – and another significant step forward in making electric vehicles an attractive and practical low carbon alternative to traditional motoring.

Whether planning the introduction of 1 or 2 vehicles or many more into your fleet – the considerations and constraints encountered by EDF Energy above, in what has been one of the largest EV charging infrastructure projects at scale in the UK - should highlight some useful considerations prior to your installation.

If you’d like further information or a survey of your site – please contact us at electricvehicles@edfenergy.com or call us on 01273 428281

*EDF Energy analysis. Based on an average of 30 charge points (required infrastructure volumes and utilisation given EV uptake scenarios charging at 32A.