The transition to electric vehicles (EVs) is well underway, and with it, the need to provide EV chargers in multi-residential buildings. What do developers, strata managers and architects need to know? And what can be done to future-proof new and existing assets? Ashburner Francis associate Toby Murdoch, an electrical engineer, explains
EV charging presents multiple challenges in terms of infrastructure and cost. It is essential to build an accurate picture of the size of the energy load from EVs and the ability to measure and allocate these costs. Central to this is an understanding of who will be charging EVs.
Parallel with the rise in EV sales has been property investor queries about EV charging . Owner-occupier purchases increasingly want access to charging points, while institutional investors want electrification in order to qualify for Green Star certification.
Designing for peak demand
EV chargers place additional demands on the electricity grid. It is critical to ensure that a building’s energy needs can be met during peak times, which may only occur a few times a year, for example when air conditioning is running in the evening. Switchboards must be designed to cope, and depending on the size of the building, transformers may be required. This can be expensive.
Whilst it may be too costly to engineer a system just to cope during peak periods, energy loads can be managed effectively using technology. A monitor on an electrical substation can send signals to the EV chargers to decrease or increase their charging rate to ensure the total building load remains safe.
Emerging technology developed in Brisbane goes one step further, using AI to tailor the
charge rate for each car. As an example, during times of high demand the system can
prioritise a car that is at 20 per cent battery charge plugged in at 5:30pm over a car with 70 per cent charge plugged in at the same time.
Emerging technology developed in Brisbane goes one step further, using AI to tailor the charge rate for each car. As an example, during times of high demand the system can prioritise a car that is at 20 per cent battery charge plugged in at 5:30pm over a car with 70 per cent charge plugged in at the same time.
In the future, there is also the potential for car batteries to feed power back into the grid in the same way as home solar batteries currently do. In this scenario, a car could power an office or home during the evening when solar power is not functioning.
New builds – get it right the first time
Asking the right questions at the beginning of the design process is key to a future-proof system. How many people will charge how many cars, at what time of the day, and with what type of charger? Superchargers can charge a car much faster than a standard charger but require DC power, an added expense.
Care should be taken not to market a development as “EV ready” without first defining what that means for everyone involved. A decision needs to be made early on whether every car space will be EV-ready and how many shared charging stations and vehicles will be available. Developers should discuss the options at the beginning of the project and architects should engage electrical engineers during the DA phase to mitigate costly mistakes.
At Ashburner Francis we have been involved in projects where the architects haven’t factored in the required space for the switchboards and transformers, and as a result, an entire apartment has to be reclaimed. Understanding and defining what’s needed may add a couple of thousand dollars in engineering fees at the start but could save hundreds of thousands of dollars later.
The complexities of retrofitting
Retrofitting offers a different set of challenges. Each property must be assessed on a case-by-case basis, with scale, existing infrastructure and geographic location all factors that impact the choice of solutions.
For retrofits, start by monitoring the existing system to measure its spare capacity. From there, work out whether it can cope with EV charging or whether we need to upgrade the system and add a transformer. This is also contingent on the grid in the local area having capacity, something the local energy supplier needs to advise on.
Importantly, EVs weigh more than petrol cars, so in older buildings with concrete floor slabs, too many EVs may mean the slabs need to be structurally reinforced.
Who pays?
This is the question that’s top of mind for everyone. Ownership structures will determine who pays for the infrastructure, factoring in what electricity suppliers in different states are willing to contribute. In most cases, privately owned assets must pay for upgrades themselves.
The cost of electricity can be allocated in different ways. In new developments of up to about eight stories, it’s not hard to feed power down from an individual dwelling to its car bay so that the electricity cost is charged directly to the owner’s bill. For larger developments where this isn’t feasible, it will be necessary to install metering devices that measure and charge by use.
For a retrofit, the owners need to fund the necessary infrastructure upgrade. As the number of EVs in general use grows, properties that don’t have the capacity for EV charging will likely lose value. However, until EVs become the norm it may be hard to convince owner-occupiers in a strata scheme to chip in. Installing communal chargers can be the best and most economic solution.
EV charging can be leveraged as a marketing tool.
Simon White is the founder of design advisory consultancy DVLP and was design manager at property developer Aria for eight years. He has seen a rapid increase in demand for EV chargers. At Aria’s ‘Upper House’, a 32-level, Koichi Takada designed tower due to open mid-2023, an EV charger backbone has been pre-installed throughout the basement and podium parking areas. Distribution boards and full cable tray runs on each level simplify the process for residents to add a charger to their own parking spaces. The capital cost means the residents can add a standard charger for around 60 per cent less than if no backbone had been installed.
At Aria’s completed development ‘The Standard’, three Tesla Series 3 vehicles were purchased and gifted to the body corporate for communal use. The building has since enlisted the services of Ohmie Go to manage the booking, cleaning and insurance of the common vehicles. The communal vehicles mean a resident has less reason to have a second car, and over time, it will help to reduce the number of cars in these buildings generally.
Strata managers beware – get it in writing
It is essential that strata by-laws reference EV charging. For example, by-laws should clearly state if charging will be slower during peak periods and define rules around when you can charge and how charging is metered. Electrical engineers can add value by helping to draft strata by-laws.
Clearly capturing the who, how and when of EV charging – whether for a new build or a retrofit – is enormously beneficial for everyone and can save a lot of arguments. It’s a valuable service that engineers offer that is not widely known or leveraged.
Amidst the rapid evolution of technology in EV batteries, chargers and the associated management software, regular communication with engineers is the best way for developers, strata managers and architects alike to stay informed and avoid costly mistakes.
