Most owners were impressed by the tech, if caught-on-the-hop by their Powerwall batteries being remotely triggered to fully charge from the grid during the wee hours, before the breakfast-time cold-snap crunch. Photo / Getty Images
Tech industry figure Matthew Harrison woke up to a surprise this morning.
His Tesla Powerwall battery had been remotely triggered during the night to fully charge, using electricity from the grid (ordinarily, the battery is used to store power collected by solar panels). It put his household in good shapefor the possible blackout.
Tesla could not be immediately reached to confirm events.
But discussion among multiple Powerwall owners on the private Solar and Self Sufficiency NZ group - and Harrison’s own analysis - indicated that with Transpower warning of possible power blackouts between 7am and 9am today, Tesla had remotely activated the Powerwall’s Storm Watch feature, which it says “Ensures that your Powerwall has enough stored energy to power the home in the event of a grid outage.”
Echoing the sentiment of many on the Facebook group, Harrison told the Herald he was happy to be enlisted in Telsa’s effort to relieve pressure on the grid.
But the owner of Taranaki wireless internet provider Primo and Technology Users Association (Tuanz) board member added, “From a customer service point of view, it would have been good to have been told that Storm Watch had been triggered.”
And then there was a mismatch between the price of charging a Powerwall, and the rate that power companies buy surplus power, which left some a small amount out of pocket (others were on plans that allowed for free or discounted charging from the grid overnight).
In the Facebook group, one user said “I paid 26c/kWh to charge overnight and exporting at 7c/kWh now.”
Others were exporting surplus solar power at 13c/kWh, or about half the amount it cost to charge their Powerwall.
‘$1.50 to help out New Zealand’
Harrison said the sums involved shouldn’t be over-egged.
“We’re talking about $3 to charge from the grid to help out New Zealand.
“And the solar we export in its place means we’re only $1.50 down.”
NZ is one of only six countries where Storm Watch is offered - though going by the social media discussion, its very existence had caught many on the hop. Once aware of it, Powerwall owners can go into settings and disable it if they wish.
Overall, Harrison said he was impressed by the tech. His Powerwall had been triggered to charge in the wee small hours, when pressure was low on the grid. “It was full by 5:30 am just in time for the 6-9am shortfall,” he said.
Tesla has been asked for comment.
Chris Keall is an Auckland-based member of the Herald’s business team. He joined the Herald in 2018 and is the technology editor and a senior business writer.