· 9 min read
This is part three of a three-part series on electric vehicle (EV) charging strategies. You can find part one here and part two here.
In conjunction with a modal shift to better public and active transport, electric vehicles (EVs) offer a massive opportunity to reduce emissions and improve urban air quality. However, crafting effective EV charging strategies requires holistic thinking at the intersection of transport, energy, the built environment, behavioural science, and economics.
Part one examined the EV owner experience and introduced charging policy fundamentals. Part two reconsidered electric vehicles as “batteries on wheels” and assessed the implications for charging policies, technologies and integration. Part three puts the charging policy onion together.
The need for smarter EV charging infrastructure
By now it should be clear that if EV charging infrastructure doesn’t become smart enough to negotiate with both the grid and vehicle owners, then we could wind up needing to “gold plate” electricity distribution by adding additional cable, substation and transformer capacity across the network.
On the other hand, if charging is smart, and, critically, if EV batteries can be used to supply to and help stabilise the grid (using vehicle to grid, or V2G), then we can potentially avoid a huge amount of investment in grid and stationary storage upgrades, and enjoy even cheaper renewable energy.
As mentioned earlier, the protocols and technology are on the way, but tariff structures that incentivise owners to leave their cars plugged in when they’re not charging might take a while to work out. After all, why would you give power back to the grid for, say, 10 cents per kWh if you have recently charged at a DC fast charger and paid 60 cents? On the other hand, if you do a lot of your charging for free off rooftop solar, that rate could be an appropriate incentive.
Meanwhile, owners with off-street parking and solar might value using their EV battery to power their home overnight, avoiding the need for a home battery. Again, smart charging is needed to match the load and ensure the vehicle still has sufficient capacity for the next day’s driving.
The trick for policymakers is scaling Level 1 and 2 charging in the right places; ensuring they are grid smart (can be ramped and throttled to meet grid, distribution network and building constraints/opportunities); minimizing Level 3 fast charging to only where it’s really warranted; and getting tariff structures right, as is summarised in Table 3.
Table 3. Charging Strategy Considerations by Location Type
Area character |
Mass Public Transit hubs |
CBDs / Office & Industrial Parks |
Supermarkets |
Residential: mainly on-street parking |
Residential: mainly off-street parking |
Highway service stations and small towns |
Parking behaviours |
Majority park for most of business day (8 hours+). |
Majority park for most of business day (8 hours+). |
Supermarkets |
Vehicles parked overnight or for multiple days. |
Vehicles parked overnight |
Transiting vehicles stopping specifically |
Level 1 (slow |
N/A |
Employers may choose to provide free use of normal power outlets rather than installing L2 charging. Or for fleet uses. Consider smart sockets linked to software that can regulate supply and recover electricity costs* |
N/A | N/A |
Many home owners with off street parking will choose level Support apartment buildings to provide |
N/A apart |
Level 2 (medium 7- |
Provide and scale L2 smart chargers at park & ride parking (7kW due to longer dwell times). |
Require commercial building parking to meet minimum L2 smart charger densities, scaling up over time. Employers may choose to add L2 chargers to support fleet uses. |
Requirements will vary by locality depending on availability of offstreet Provide and scale; throttled dependent on available building/ |
Initially: light pole chargers. |
Support apartment buildings to provide supporting infrast Charging software systems could be |
N/A apart |
Level 3 (fast 50kW+ charging) |
Not required. Typical dwell time exceeds efficient utilisation of L3 fast chargers. |
Provide limited on-street L3 smart fast chargers in strategic locations for commercial vehicle top ups. Employers may choose to provide L3 chargers to support fleet charging needs. |
Assess and provide limited L3 fast chargers for distributed fleet users on short breaks (e.g. taxis). |
Not required. | Not required. |
Provide at stopping points that have existing food / shopping / recreation amenity. |
eBike/ |
Provide and scale (no cost to public transport users). |
Require private end of trip facilities to provide. |
Not required. | Not required. | Require new apartments to provide infrastru cture. |
Not required. |
Solar/ |
Require solar canopies over carparks. |
Require solar canopies over car parks. | Require solar canopies over car parks. | N/A | N/A | Provide to support higher charging density in areas that have insufficient electrical capacity. |
Tariff structure |
Ultra cheap day time charging aligned with peak solar. Throttled from evening. | Ultra cheap day time charging aligned with peak solar. Throttled overnight (when such car parks generally see low utilitsation). | Cheap day time charging. Throttled during evening peak; mid price overnight (if parking facility remains open). | Cheap day time charging. Throttled during evening peak; mid price overnight. | Time of use tariff for EV charging, aligned with renewables generation and shortfalls. | Commercial rates set by third party charging service providers. |
*For example, Australian start up Alchemy Charge retrofits existing electrical sockets with networked smart sockets linked to software that allows the building owner to set tariffs and control usage. A QR code at the socket allows vehicle users to provide payment details and monitor their charging. This is a solution for apartment or condominium buildings where there may be limited electricity capacity, or where power in the carpark is provided from the common area electricity meter rather than individual apartments’ meters.
**Regulation is required to improve fire safety for e-micro mobility devices such as ebikes. Product standards and clearer owner guidance are essential. Sophisticated battery management and cooling systems in electric vehicles mean the risk of fire is far lower than for smaller battery-powered devices.
Putting the onion together – policy layers
Orchestration is the name of the game. For policymakers, the first step is to establish collaboration across levels of government, plus local utilities, major fleet managers, charging operators and EV original equipment manufacturers (OEMs). This range of stakeholders can provide valuable insights into actual and potential charging behaviours.
Clear targets for EV adoption (and therefore fleet density) will help policymakers plan appropriate charging infrastructure. Keeping the pace of charger adoption slightly ahead of the percentage of EVs in the fleet will improve vehicle buyer confidence, but if the provision of chargers is to be left to private companies, will rely on subsidies and/or patient capital.
Governments should oblige utilities to model the impact of electrification of transport and buildings at various densities against differing assumptions about the role that EV batteries and other distributed energy resources (DER: including rooftop solar; home, business, network and vehicle batteries; and demand management such as time-shifting hot water systems to periods of abundant solar, throttling battery charging rates; or being able to temporarily relieve air conditioning loads or commercial refrigeration to avoid destabilising local network nodes or the broader grid).
The objective of such scenario modelling should be to accommodate varying levels of vehicle fleet and building electrification (10% to 100%) while minimising network upgrades, given assumed uptake and uses of DER. Private network operators may require incentives or regulation to encourage them to undertake such modelling, particularly where it might conflict with network revenue structures that are based on a guaranteed return on capital.
It's clear that consistent protocols, standards, regulations and tariff structures are critical to ensure that, moving forward, EV chargers (including those installed in private buildings) have the smarts to support V2G, and the ability to be remotely throttled by network operators during periods of supply imbalance. EV manufacturers might need encouragement to ensure some of the orchestration features can be enabled.
(As an aside, a small enabler would be to facilitate “plug in and go” charging, where there is no need to have multiple apps or RFID fobs to use different chargers – a driver can pull up at any publicly accessible charging point, plug in, and tap with a credit card as easily as paying for parking. Perhaps there could be an “umbrella” app that will recognise the particular vehicle when it’s plugged in and link it with the owner’s preferred payment method, regardless of which company owns and manages the particular charger.)
More broadly, a range of overlapping federal, state and municipal policy areas should be harmonised, including aspects such as:
-
transport budget allocations
-
urban planning
-
building standards (including increasing minimum electrical capacity)
-
energy tariffs and network cost recovery structures
-
electricity grid and network planning
-
electric vehicle & charger standards
-
parking policies
-
public transport investment
-
taxes, duties, rebates and subsidies
-
public education and messaging programs
While EV charging strategy is complex and uncertainties remain, analysis and planning incorporating the foregoing considerations should lead to superior policy outcomes in terms of accelerating the transport transition.
What we need is enough reliable, simple and smart charging options to give more people the confidence to ditch their gas guzzlers and join the EV revolution. And, better still, enough cheap, convenient and reliable public / shared transport to give many people the confidence to ditch or downsize their gas guzzler altogether and make a substantial dent in the size of national vehicle fleets.
Governments must work collaboratively to avoid the potential EV millstone, instead seizing the enormous opportunity they provide to lower power prices and avoid massive infrastructure investment.
illuminem Voices is a democratic space presenting the thoughts and opinions of leading Sustainability & Energy writers, their opinions do not necessarily represent those of illuminem.