In Sept 2023, the OC and Grant Committee did some preliminary research scoping cost and infrastructure requirements for charging cars at The Rochester followed by a poll open to all residents assessing our level of readiness and interest in EV charging. Here is a summary of the poll feedback.
A. Four to six EVs could potentially plug in to the domestic 10 amp power points in the basement and draw a trickle charge (about 10-15 kms of travel/hour of charging). More cars than this creates a high risk that the demand for power will cause instability in the electrical system and trip out the whole building.
A. To use a domestic power point safely you need to use approved single cables for your vehicle and ensure cables are not a trip hazard. All leads need to be tested and tagged by an electrician before use. Cables should not run along the ground as we have a 'wet' basement and in times of heavy rain it is common for water to be trailing across the floor.
A. Yes and no. The electrical engineer for The Rochester has given some of the back history. Initially the building was designed to have the electrical capacity to allow every owner to install EV charging. This was to be achieved through an on-site substation receiving a high voltage supply. Because only two lots opted for an EV charger at time of purchase, the developer reduced costs and did not proceed with the substation.
The two apartments that opted for EV charging, off-the-plan, got a local workaround for their wiring that was within the capacity of the revised electrical design.
A. The Rochester has a low-voltage supply of 215 amps (equivalent to 77 KVA) which is called the Maximum Demand for the building. If this demand is exceeded the building circuit breaker activates to protect the circuits.
Our real time demand varies throughout the day and over the seasons. Metered power use for 2022 shows there is surplus capacity in the system to charge EVs. In 2022, the maximum demand was about 48 KVA (on a cold July afternoon) while the minimum demand over summer (when hydronic heating was off) was about 6 KVA. There is spare capacity that could be used for EV charging, but charging would need to be done at the right time of the day, and staged across vehicles though the use of a Load Management System.
A. A LMS monitors the power demand of each charging station and allocates the available electrical capacity among them. The LMS ensures that the total power consumption doesn't exceed the capacity of the electrical infrastructure, preventing overloads and voltage drops. The LMS can take advantage of lower electricity rates during off-peak hours, scheduling charging for EVs when electricity is cheaper, and collects data on charging station usage and power consumption to streamline billing systems.
A. Once we have more than 4-6 owners/tenants wanting to charge their EVs at home the current electrical system cannot deal with the load. Once we reach > 4-6 EVs access to common area charging will have to be restricted in both number of power points and time spent charging. This becomes unworkable for those driving any distance each day, as the charge rate of 10-15 kms/hour is not going to be useful to anyone if you can only charge for an hour or every second day.
Although we have spare capacity, The Rochester is going to need to be really efficient with how that electricity is used for EV owners to get enough charge to be useful for a daily commute.
A. If you have an EV charger at a house, you do not need a LMS. Currently a home EV charger costs in the order of $600-$2,500 plus installation of $500 -$1,500 depending on the location of existing wiring and any upgrades needed. See NRMA EV Charging $
Where an LMS is operating, the charger needs to have extra “smarts” to talk to the system to manage the load and record electricity use for billing. These chargers are more expensive costing in the order of $2,600-$5,400 installed.
A. The Rochester OC Committee has two quotes for EV infrastructure from mid-2023, both relatively close to $80,000. Without a crystal ball we won’t know if this is enough when time comes to do the work but it is the best estimate we can make. If we proceed with the work, the funds will be raised through a Special Levy over a couple of years with quarterly payments indexed to CPI to help account for the likely rise in prices for materials and labour over time.
A. Yes – is the easy answer to this question! Technologies are rapidly evolving and in the future are likely to have the capacity to manage both behind the meter demand and grid demand by using EV batteries as energy storage. The risk of EV charging technology being superseded will be managed through the consideration of lease versus owned assets when the system is being specified ready for installation.
A. Local real estate agents report that there is no established price premium yet for apartments that provide EV charging. Feedback from agents is that there are two demographics asking about EV charging at open house viewings – Baby Boomers and Millennials. The median difference in price of apartments with and without an ordinary car park is well established and is in the order of $185,000 for apartments in our area. The premium for access to EV charging is likely to be lower than that for a parking space but still likely to be significant. The majority of Lot Owners at The Rochester believe EV charging infrastructure will add to the capital value of their apartment and its attractiveness as a rental.
In Sept 2023, residents of The Rochester were polled on their thoughts about EV charging. The responses are summarised here.
Click here to check out the interim and long term plan for the Rochester
For the full analysis of how the Rochester will transition to full EV capability, click here