The demand for Electric Vehicle (EV) charging facilities in residential strata is expected to lead to a significant increase in energy consumption in years to come. In the case of Blackwattle Mews it is likely that owners and residents will start installing charging facilities in their individual garages. This is easily facilitated as the final electrical distribution board for each townhouse is located in the garage. In considering the trends in EV adoption it would be prudent to design the solar system and allow sufficient capacity from the main switch board and sub boards to cater for this future demand.
Blackwattle Mews has undertaken a electric vehicle survey report to gauge interest from residents on whether they would purchase an Electric Vehicle. Seventeen residents have responded to the survey out of a total of 18, which is a high response rate. The results show that 7 residents are interested in purchasing an Electric Vehicle within the next 10 years. In addition, 14 residents are against providing a charging facility to the public and most want individual chargers on their car spaces.
The survey results also shows that the average driving distance for residents is approximately 106km per week. Using the data for an Electric Vehicle model currently available in the market, the annual energy consumption is calculated to be 1,275kWh. If we assume 7 residents get Electric Vehicles and install charging within the next 10 years, the additional load impact is estimated to be 8,925 kWh. If this additional energy demand were to be accommodated with solar power, the additional solar system size that would generate the equivalent amount of energy is calculated to be 6.6kW.
However, it needs to be highlighted that the interest in purchasing an Electric Vehicle may change over time. For example, government incentive programs and the installation of additional public charging stations can encourage a higher uptake of Electric Vehicles by residents. This may translate to a larger solar system size being required to offset the load from Electric Vehicle charging.
Another consideration is whether or not residents who own an Electric Vehicle would be charging their vehicle during the day. Residents who work from 9 to 5 may prefer to charge their vehicle over night to ensure the battery level is full the next day. This only leaves them the opportunity over the weekend to utilise solar power for charging. On the other hand, retirees who are at home during weekdays would be able to utilise more solar power in comparison with others. As a result, the solar system size that is suitable for charging electric vehicles is heavily dependent on the charging behaviour of residents.
The Owners Corporation may wish to take a long term view on the potential impact of electric vehicle charging in consideration of the overall electrical network design and solar sizing. Assuming 100% adoption of electric vehicle charging, this could account for approximately 25% of the energy usage of the site. Once several electric vehicle charging facilities have been installed at the site, there may be additional demand from the rental market and property buyers. Over time those seeking existing EV charging facilities or ease of installation may drive additional property demand and therefore higher EV adoption rates than indicated by the survey results.