Electric vehicles (EVs) are slowly becoming more popular in Australia, with new car sales increased during the last two years. Although Australia is behind in EV deployment compared to other countries, Federal and state governments have taken serious steps to accelerate EV uptake. Therefore, EVs could play a significant role in the future of the National Electricity Market (NEM), especially after 2030, when EV uptake could exceed 7,000 MWh based on the forecast in AEMO’s Step Change scenario.
On the other hand, EVs could be beneficial to the NEM, acting as “batteries on wheels”. However, to realise these benefits requires an evolution in how we think about EVs. Simply put, EVs can help the grid in two ways, including:
- Managed charging: A charging management aims for EVs to be charged during solar peak and/or midnight.
- Vehicle-to-grid (V2G): Employing V2G technology that provides the grid with energy and frequency control supports, making EVs an opportunity rather than a challenge.
EV deployment in Australia is comparatively low compared to other countries due partly to a lack of solid infrastructure to support EV uptake. However, as EV uptake increases, charging management developed via efficient policy and regulatory guidelines is a feasible and realistic initial solution to EV integration into the NEM.
In this regard, there are a number of questions that should be addressed:
- Which groups of EVs (passengers, trucks, buses, commercial buses, etc.) are the largest in terms of annual load demand?
- Are these groups flexible enough to shift their load if required?
- How much GWh of EV load can be shifted to high renewable generation hours by changing EVs charging patterns?
- How much GW would AEMO expect as the maximum EV load demand during a peak dispatch interval?
To answer these questions, in this Chart of the week, Cornwall Insight Australia simulates the growth trend of EVs across different groups in terms of annual load. Then, the most potential group/s will be selected based on their total EV load and also flexibility to shift their charging profile to high solar/wind generation hours. Finally, the potential GWh of shifting for the most extreme EV load scenario is evaluated to realise the expected renewable generation utilisation.
Our simulations show that the passenger EV group has the highest load demand among all EV groups, with an average yearly share of around 75%. Passenger EVs have higher aggregation potential and flexibility to shift their charging time compared to other groups as well. Therefore, it will be more beneficial for retailers and EV aggregators to focus on this group. Based on these simulations, the range of passenger EV capacity forecast over a 30-year period is displayed in Chart 1. The range represents the passenger EV capacity in high population-high EV to low population-low EV uptake scenarios. In this regard, AEMO could deal with an uncertain daily EV load in the range of 16.18GWh to a staggering 36.61GWh for the passenger group in the year 2052, based on our model.
An outstanding concern about the high EV penetration is power system constraints after a sudden rise in EV charging load during peak time. Chart 2 shows three potential EV charging approaches, while the objective is to switch passenger EVs load from peak period (convenience charging – CH1 in Chart 2) to high solar/wind generation periods (midday and night charging – CH2 and CHE3 in Chart 2 respectively).
As can be seen in this chart, by 2052, the convenience charging profile results in a 3.13 GWh EV load during the peak interval of 20:30 in the extreme high population-high EV scenario. By shifting from convenience to midday charging (CH1àCH2), 11.02GWh more utilisation of solar generation can be obtained. Similarly, 11.55GWh more wind power utilisation/less curtailment is expected by changing the charging pattern from convenience to night-time (CH1àCH3).
While this is an extreme scenario, it is necessary to highlight the role of governments and aggregators in offering some incentives to EV customers and persuading them to change their charging habits.
Cornwall Insight Australia recently presented a webinar on the state of the EV market in Australia. The webinar explored the EV market to date, projections for the future and regulatory and market changes needed to manage the EV uptake. For a copy of the webinar slide deck, please contact us at enquiries@cornwall-insight.com.au.
