With over 100,000 electric vehicles (EVs) in the Pacific Gas and Electric Company (PG&E) service area of northern and central California placing increasing pressure on the electric grid, the utility could have viewed this growth with dread.
However, the utility sees EV drivers as a “growing resource” and is keen to understand the full potential of EV charging and how it can help stabilise the grid and support the integration of renewables.
The utility adopted a two-phase two year pilot, ChargeForward, alongside vehicle manufacturer BMW to research the potential benefits that EVs can bring to the grid. The programme, launched in July 2015, involves the incentivising of EV drivers to participate in demand response (DR) programmes.
BMW i3, BMW i8 and iPerformance EV and plug-in hybrid EV owners in the greater San Francisco Bay Area who are also PG&E customers have been encouraged to participate in the programme which focuses on managed EV charging.
During the trial, BMW will manage the at-home and on-the-go charging of selected BMW i3, BMW i8 and iPerformance vehicles in partnership with PG&E to optimise grid reliability and support renewable energy integration.
The first phase of the pilot, which ended in December 2016, highlighted the viability of creating grid value by optimising EV smart charging. Now PG&E and BMW are in the second phase of the programme to test how well EVs can support the grid and integrate renewable energy through smart charging anywhere - not just at home.
Funding for the second phase was secured by BMW through a competitive bid for a California Energy Commission grant.
Phase 1-Optimising smart charging
The first phase of the ChargeForward pilot involved 100 BMW i3 drivers located in the San Francisco Bay Area. The incentives existed for the duration of the pilot from July 2015 through December 2016.
Participating customers received an upfront incentive to enroll and an ongoing incentive based on their performance in reducing load. Each customer was able to track the value of the ongoing incentive as well as opt in or opt out of each event via a phone app throughout the pilot.
BMW developed solutions that use the vehicle’s current communication system to create value for customers and improve grid reliability through DR.
PG&E sent signals to BMW requesting a load reduction on the grid of up to 100kW. In response to these DR signals, BMW selected vehicles for delayed charging – up to one hour delay per day – based on drivers' needs. Participants could choose to opt-out of participation if they needed to begin charging their BMW i3 immediately. BMW supplemented the smart charging of these vehicles with a solar-powered energy storage system made from "second life" EV batteries – lithium-ion batteries from old MINI E demonstration EVs – as a back-up to support the grid during these demand response events as necessary. The results of the first phase are impressive. Satisfaction levels of participants reached 92% and 86% are likely to recommend it to family or friends. A total of 209 DR events took place from July 2015 to December 2016. In 94% of the DR events through October 2016, BMW successfully reached the full grid load reduction of 100kW requested by PG&E.
By August 2016, over 20,000kWh were shifted as a result of ChargeForward events – enough to power the electricity for two homes over one year, thus avoiding costly and carbon-intensive electricity generation.
Ari Vanrenen, Corporate Relations, PG&E told Engerati: “This is the first pilot that PG&E has run that specifically leverages a combination of managed charging and used EV batteries. However, this pilot programme is similar to what other large industrial and commercial customers do today as part of PG&E’s DR programmes.
“The pilot demonstrates that EVs can be an effective grid resource. Through our customer research, we have learned that asking customers to delay charging can be achieved with minimum disruption to customers.”
Phase 2-Optimise the EV charge anywhere
Building on the functionality tested in the first phase of the initiative, the second phase will explore the ability to optimise charging events regardless of where the vehicle is charging.
The aim is to broaden and test new smart charging functionalities, creating more benefits for the grid as well as EV drivers. This includes for instance the optimisation of charging across multiple charging events, shifting charging across grid locations, and adjusting charging according to the level of renewables on the grid.
BMW has engaged with over 250 BMW i3, BMW i8 and iPerformance drivers in the greater San Francisco Bay Area to participate in the second part of the pilot. Through BMW ConnectedDrive, which enables connectivity between cars, drivers and their surroundings, and the BMW ChargeForward smartphone app, participating drivers can opt-out of any smart charging requests when necessary.
If they don’t, vehicle charging can be shifted to meet the needs of the grid especially during peak times. Participants can earn up to $900 for participating in this pilot, with all participants receiving a $300 initial incentive.
The total amount earned over the two years depends upon individual participation in charging events. Customers may also have the opportunity to earn additional incentives for participating in short-term charging tests, or sub-pilot projects, that may occur during the period.
The goal of the pilot is to make smart charging more beneficial to the grid and more rewarding to participating drivers. By sharing the benefits of this optimisation with EV drivers through incentives, smart charging helps reduce the total cost of EV ownership which may encourage adoption, adds Vanrenen.