Why more electric vehicles won't make the lights go out

Energy Minister Megan Woods responds to the power cuts in August, ahead of the subsequent inquiries into the incident.

OPINION: When the power goes out on the chilliest night of the year, it stands to reason people would ask who was using so much that demand outran supply. And it’s no surprise, with the recent interest in electric vehicles (EVs), that many were wondering whether EV drivers were draining the grid, and if that will become more of a problem in the future.

The answer to both those questions is no.

Last week, the New Zealand vehicle fleet hit a milestone – more than 30,000 EVs are now on the road. While that number has grown considerably in the past few years, it still represents only about 1 per cent of all light vehicles in the country. And last Monday, when the power went out in parts of the country, their charging demand was less than 1 per cent of the total demand (an estimated 42 megawatts of the peak of approximately 7142MW).

Total cost of ownership of an EV is already cheaper than ICE vehicles in some cases. That’s only going to become more common.
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Total cost of ownership of an EV is already cheaper than ICE vehicles in some cases. That’s only going to become more common.

Electrification of the fleet is key to driving Aotearoa New Zealand’s emission reductions, and as the EV fleet continues to grow, there is enough capacity growth planned to meet it. EECA is also working with others from across government and the private sector to encourage the development of smart charging for all consumers.

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A smart charger will enable consumers, or their lines company, to monitor and manage their EV charging to take advantage of low off-peak prices but still ensure their EV is charged and ready to drive. This will be especially important as more consumers choose to drive EVs.

An EV charging station in Nelson. Soon smart chargers at home will allow users to take advantage of off-peak prices.
MARTIN DE RUYTER
An EV charging station in Nelson. Soon smart chargers at home will allow users to take advantage of off-peak prices.

In addition, advances in vehicle-to-home, or vehicle-to-grid, technology would allow your car to power your house, if needed, or even feed power back into the grid.

But efficient, smart technology doesn’t end with EVs, and we must ensure we’re using our electric goods as efficiently as possible. The good news for Kiwi consumers is they can be reassured that our regulations prevent poorly performing appliances from coming into the country: for example, last year, New Zealanders bought 235,000 new heat pumps, all of them energy-efficient due to the regulation around their efficiency.

Across all our regulated products sold in the 2019-20 year, Kiwis saved $31.4 million in energy costs, and reduced the amount of electricity it would take to power 35,000 homes.

Heat pumps are already energy-efficient, and can respond to signals that change how much energy they use, writes Marcos Pelenur.
Stuff
Heat pumps are already energy-efficient, and can respond to signals that change how much energy they use, writes Marcos Pelenur.

There’s a future for even more smart technology and devices to come online to help continue to smooth those demand peaks and ensure a more resilient system.

For decades, many hot water cylinders have had “ripple control” to help manage peaks on the local network. As a customer, this “demand management” happens without you even knowing.

Modern technology has the potential to take demand management to the next level to help keep New Zealand’s electricity supply reliable and cost-effective, and reduce the likelihood of power outages. More and more appliances, such as heat pumps, can respond to signals that change how much energy they use.

Marcos Pelenur is group manager of strategy, insights and regulations at the EECA.
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Marcos Pelenur is group manager of strategy, insights and regulations at the EECA.

To the consumer, these changes could be unnoticeable (apart from a lower electricity bill), but at a system level, they’d have a significant moderating effect on the peaks.

Energy, and especially electricity, are fundamental to modern life, and energy efficiency and increasingly demand management will help keep the lights on. Together they can defer the need to invest in as much new generation and transmission, saving all New Zealanders money.

Dr Marcos Pelenur is group manager, strategy, insights and regulations at the Energy Efficiency & Conservation Authority (EECA).

An earlier version of this article said the charging demand from EVs on the night of the power cuts was less than a tenth of 1 per cent of total demand. In fact, it was less than 1 per cent. (Amended August 19, 2021, 10.37am)