Electric vehicle (EV) charging sites with a greater number of charging plugs are more likely to see increased utilisation compared to sites with fewer plugs but more charging power.
These findings headline a new white paper produced by Finnish charging company Kempower, which operates around the world, including in Australia where it has a growing market share.
The findings are based on North American data collected by the company’s cloud-based EV charging management software, ChargEye, but there’s no reason to think that they would not apply in Australia, which – because of its long distances – has tended to focus on EV charting stations with just one or two bays, although that is slowing changing.
According to Kempower’s research – which is based on real-world charging data rather than customer surveys – utilisation of EV charging sites “depends far more on plug density and dynamic power sharing than on installed power alone.”
In fact, the data shows that a site’s installed power doesn’t really influence driver behaviour at all, with a correlation factor of only 0.22 between charging site utilisation and total installed power on site.
Conversely, the correlation factor between utilisation and the number of plugs is three times as high at 0.63. According to Kempower, “charging site utilisation climbs steadily as sites add charging points”.
For example, the data suggests that a site with 8 charging plugs delivered more than double the energy of a site with 4 plugs – 128,342 versus 61,453 kilowatt-hours (kWh).
And as public charging becomes not only more ubiquitous but also a more attractive infrastructure business opportunity, the focus will increasingly be on how operators can secure a greater return on investment.
With revenue for charge point operators coming from kilowatt-hour delivered rather than the speed with which a car is charged, the white paper finds that “more plugs translate directly into higher revenue potential”.
This doesn’t mean that charging speed doesn’t matter, but EV charging sites are traditionally designed around theoretical peak demand which, in practice, is rarely sustained. As such, “charging site utilisation is shaped more by operational dynamics — concurrent charging and power-distribution efficiency — than by absolute capacity.”
Designing EV charging sites, therefore, should focus more around “efficient power allocation and higher plug accessibility, so capacity is actively used, not passively provisioned.”
“Size EV charging sites around real demand and share power dynamically across more plugs, rather than provisioning peak power per outlet,” the white paper suggests. “Distributed charging reallocates unused capacity from idle plugs to active vehicles in real time, so each installed kilowatt works harder.”
“Public charging is increasingly becoming an infrastructure utilization challenge, not simply a power deployment challenge,” said Jed Routh, vice president for markets & products North America at Kempower.
“Our ChargEye data shows that giving more vehicles access to charging and dynamically distributing available power can help operators get more from their charging infrastructure.”
Kempower’s white paper also found that average EV charging sites using distributed charging achieved an 83 per cent higher utilisation rate than fixed-power charging sites.
