How to optimise home EV charging to soak up rooftop solar and overnight troughs

Energy retailer Origin Energy, the country’s largest, says it is having big success encouraging its EV-driving customers to push their home charging times either into the middle of the day, to soak up rooftop solar, or to low demand periods overnight.

“We’re very excited by what we’ve been able to achieve in that regard,” Origin CEO Frank Calabria told analysts in a briefing for the company’s half year results on Thursday.

Calabria says the graphs below show how demand for EV charging – and electric hot water heating – can be shifted through optimised tariffs.

“What we’ve demonstrated on the right hand side is … how that benefit can be realised by shifting loads to times of low demand or high supply, whether that be overnight or whether there’s an abundance of solar energy,” he said.

“We’re applying and actively managing that to a bunch of customer cohorts now and continuing to refine. “Our focus to date has been on scale connections and technical capability, and it’s increasingly moving towards the customer propositions.”

The graph are important  because they illustrate how behaviour can be changed through tariffs, and why EV charging – and other consumer demand for that matter – does not all have to happen in the evening peak.

And it also points to the immediate future, with Daniel Bleakley reporting on how Origin’s partly owned Octopus Energy introducing the first V2G tariff in the UK, with savings of up to $1,640 a year. See: Costs down, resilience up. First vehicle-to-grid tariff to save drivers $1,640 per year

In the graph above on the right, based on what Origin is doing here so far, the blue line shows the baseline, what most people would do given no incentives, and they tend to charge their EVs in the evening.

The red line shows how that demand shifts to the middle of the day and soak up solar, and the yellow line shows how it can be shifted to the middle of the night, when there is normally low demand.

Origin says it is also growing its electric fleet offering, with 90 businesses with more than 600 EVs now participating in its program and new products.