When installing EV infrastructure in a strata building, there are two options for where to draw the power from. These are either from the building’s power or from the individual residents power. Which one you choose depends on a number of factors which I’m going to take you through today in this video.
So we’ll start off with connecting to the building’s power.
This is the most common approach taken in strata buildings. It involves powering all the EV charging stations through the building’s centralised power. This means that the owners corporation is being charged for the residents’ power usage.
The main benefit of this approach is that it costs the residents less to charge – this is because the building is buying the power at a wholesale rate vs a retail rate. So when the resident’s are charging, they are paying significantly less per KW verse what they would be paying if they were using their own power and being charged directly by their energy retailer.
There are a few things to consider though when connecting to the building’s power. Both load management and billing software will be required.
So load management software is necessary to make sure that the circuit isn’t tripped when EV chargers are in use. It does this by dynamically working out in real time what power the building has available and then evenly distributes this to the EV chargers in use. You can check out our load management video for more in-depth information around load management.
Billing software manages all the payments for the resident using the building’s power. So how it works is really simple. It charges the resident for their usage at the time of charging their vehicle and then this is reimbursed to the owners corporations bank account on a regular basis.
So what are the costs associated? Well, there is an annual subscription for load management and billing. This varies depending on the provider but is generally around $150 mark per year. This is charged directly to the EV resident, not the owners corporation.
Now onto connecting to the individual’s power.
So connecting to the individual’s power involves running their EV charging station off their individual main switch. This is the less common approach and is generally only suitable for smaller strata’s whose resident’s main switches are located in the carpark and also have enough capacity. So let’s unpack both of those for a second.
In order to connect to the residents power, their main switch needs to be located in a central location in the carpark. This is generally not the case for the majority of buildings that we go into, with most resident’s main switches being located in the apartment themselves. This means that in order for us to connect their EV infrastructure to their main switch, we would have to run cabling from the residents apartment all the way to their car space. As you can image this isn’t a viable option because of the cost to run the cables but also because there generally isn’t a suitable pathway to run the cables in the first place.
The other requirement is that the individual has a large enough power supply on their main switch. So all residents will have what we call a main switch. These come in all sizes and determine how much capacity they have in their apartment to run all their electric devices. So their dishwasher, their lights, their heaters and so on. If they’re running their EV charging station off their main switch, then it needs to be at least 63 amps. This is because a single phase EV charging station at full charge will use 32A of power, so straight away when they want to charge their vehicle they would be using over half of their capacity. If their main switch doesn’t have enough capacity then their power would trip every single time they plugged their EV in to charge, so it wouldn’t be viable. In most strata building’s the residents main switches are less than 63 Amp so again this is often a limiting factor for most buildings being able to connect to the resident’s individual power.
That being said if your building has the residents main switches in a central location in the carpark and they are at least 63 amps then connecting to them is the best option. The main benefit of this approach is that no load management or billing software is required. This is because the power is being drawn from the residents power and is charged directly to them by their energy retailer. So this would save the resident $150/year for a load management and billing software subscription, however you would also need to take into account the fact that they would be paying retail rate for their electricity not wholesale rate, so the cost saving would actually be less.
So that’s a little bit about the difference between connecting to the building’s power vs the individual’s power. As always we recommend getting in touch with us here at EV Installations, to help you to determine which approach is best for your building and to help you get started on your EV journey