Solution Guidelines
Guidelines for Strata
It is expected that all strata will eventually need to make provision for electric vehicle charging facilities. These guidelines are provided to assist strata in that process and demonstrate various options according to building layout etc.
The Breakfast Point EV team has built a decision tree to help navigate strata through the various EV charging options.
A PDF version of this decision tree page may be downloaded here.
About the options
The complexity of both the installation and of allocating usage costs generally increases in order of the options.
Options 1-3 are configured to limit the power to the EV charging circuit to be within the design load for the individual apartment and/or the design load for the related phase.
Options 4 and 5 that utilise common property power need to ensure that the design parameters for the building as a whole are not exceeded. There are relatively inexpensive modules that provide dynamic load management and real time monitoring of the power usage to ensure EV power usage has no negative impact on the overall property supply.
For Options 1, 2a and 3 the full cost of both installation and power usage is covered by the Lot Owner and require the appropriate bylaws and limits to be in place. Where wholly or partly available these options are likely to be a preferred for both the Lot Owner and the Owners Corporation.
For Options 2b, 4 and 5 it would be expected that the Owners Corporation would need to fund all costs related to common property and typically the Lot owner would fund the supply and installation of the individual charger and any cabling specific to that charger.
Options 4 and 5 would provide the opportunity for the Owners Corporation to set a cost surcharge as a mechanism to recover the original capital costs in the long term and cover any ongoing management costs. The level of surcharge may be dictated by the level of usage.
For Option 5 there will potentially be an ongoing management charge that will vary depending on which third party provider is contracted.
It is possible that the Options 1-3 may co-exist with either Option 4 or 5 within the one building depending on the particular building configuration. In this circumstance the Owners Corporation may need to determine the appropriate mix of options. Maximising the use of Lot Owners power by accessing their A/C circuits or direct from their basement meters could maximise the available excess power for Options 4 and 5.
Option 1
EV Charger Power Sourced from Owner's AC Circuit
Use of the air conditioning power supply circuit in conjunction with an EVSE unit that incorporates active power management. The EVSE current sensor monitors the power being drawn by the air conditioning compressor and allocates any surplus power to the EVSE unit. The current limit specified in the EVSE unit may need to be adjusted to reflect the variation in connected load factor for air conditioning vs EV charging.
Option 2a
EV Charger Power Sourced from Owner's Basement Meter
Use of the output power from the dwellings meter in conjunction with an EVSE unit that incorporates load management. The EVSE current sensor monitors the total power demand of the dwelling, including EV charging, and reduces or disconnects power to the EVSE unit subject to a pre-determined limit. This limit will be related to the excess capacity determined for any individual phase of the supply. Excess capacity is more likely to occur during overnight off peak periods, ie 10 pm to 7am and should take into account the number of installed EVSE units per phase. The implementation of a predetermined limit can provide an interim solution until such time as an alternative solution might be required. Alternative solutions may include reducing the limit, rostering the available charging times or superimposing a “whole of building” dynamic load management system over the various individual EVSE units.
Option 2b
EV Charger Power Sourced from Owner's Basement Meter with Building Level DLM
This would be implementation of the “whole of building” DLM and in this case individual EVSE units would need to be OCPP compliant to communicate with the dynamic load management system. It would be prudent to initially specify an EVSE unit with OCPP compliance to ensure it can be integrated into an overall dynamic load management system if subsequently required. The dynamic load management system would need to be funded as an Owners Corporation facility.
Option 3
EV Charger Power Sourced from the Lot Owner's Distribution Board
Similar to Options 2a/2b but with power derived from the distribution board located within the dwelling. This potentially requires an existing riser to provide access for cabling between the dwelling and the related garage. Some newer buildings are providing risers specifically for EVSE cabling to comply with BCA requirements but having this option would be rare in Breakfast Point. There may be some ground floor apartments where cabling between the dwelling distribution board and the garage may be possible.
Option 4
EV Charger Power Sourced from Common Power and Regulated by Time of Day
There have been some implementations outside of Breakfast Point that have installed an entry level system using common property power where charging is limited to overnight off peak times and the power used is individually metered and billed by the Strata Manager. This is generally restricted to a limited number of users and at the present time the relatively low of cost dynamic load managements systems makes them a preferred option.
Option 5
EV Chargers Controlled by a Load Management System
Power is sourced from the building's common power. The Owner's Corporation installs the framework including a dynamic load monitoring system. Cabling to individual garage and wall charger is at the Lot Owner's expense. Typically installed and managed by third party provider. May have ongoing management fees.