Bryan Leyland: Things you know that ain't so - electric cars

"Things you know that ain't so - our renewable energy resources will charge our electric cars."

The government is promoting (in effect, subsidising) electric cars because it believes that the electricity they need to charge the batteries will mostly come from our renewable energy resources – hydro, geothermal and wind.

The reality is somewhat different as you can see from my comments on a recent government press release:

New Zealand is one of the most EV-ready and friendly countries in the world. That’s because just over 80 percent of the country’s electricity is generated from renewable sources.

This is true but seriously misleading. Our renewable energy stations are fully committed to supplying existing loads. Fossil fuelled generation is running for more than 90% of the time and it supplies all new loads. Putting it another way, if the load suddenly dropped 100 MW the fossil fuel stations, not the renewable energy stations, would reduce output to accommodate the change.

New Zealand has more than enough consented renewable electricity generation waiting to support the widespread adoption of electric vehicles.

This may be true but, in reality most of it would not be used for changing electric vehicles because much of the charging load would be concentrated in the early hours of the evening and simply extend the period of the evening maximum demand and, inevitably, be met by fossil fuel generation. It is important to note that hydropower generation that could concentrate its operation over the peak demand period is violently opposed by the environmentalists, geothermal generation runs flat out all the time and wind generation is completely unpredictable.

Electric vehicles will replace petrol and diesel with clean, green, locally produced energy, lessening our reliance on imported oil.

This is true, but, given the low price of oil and the huge resource still available, is relatively trivial.

High renewable energy levels mean that the emission reduction benefits of electric vehicles in New Zealand are greater than in other countries.

Yes, but, as discussed above, not by much. As many studies show, it is a very expensive way of reducing emissions of carbon dioxide.

New Zealand motorists drive on average 29 kilometres per day. Average commutes in urban centres are even shorter, at about 22 kilometres a day—a distance electric vehicles can handle easily without recharging.

While this is true, it ignores the fact that most people rely on their car to transport them for the occasional long distance trip. Few people would tolerate having to stop for half an hour or more every 100 - 200 km to top up the battery.

85 percent of New Zealand homes have off-street parking, meaning electric vehicles can be easily charged overnight at home.

More and more people are living in townhouses and apartments where it would be very difficult to arrange for a charging point complete with its own meter.

New Zealand’s 230-volt electricity system means every home has the potential to charge an electric vehicle.

A standard 10 amp socket will give an 80% recharge to a 90 kWh Tesla Model S in 10 hours and virtually double the peak demand of the house. A 32 amp socket will do it quicker but it will result in a huge increase in household peak demand. As people move on to cost reflective tariffs, peak demand will become more and more expensive.

Electric vehicles are cheaper to run than petrol or diesel vehicles. On average, charging an electric vehicle at home is equivalent to buying petrol at 30 cents a litre, compared to petrol, which is around $2 a litre.

For certain, the fuel cost is less. According to the Electric Power Research Institute of the USA the overall ownership cost of a Nissan Leaf is comparable with the cost of a similar sized petrol vehicle. But it is important to remember that, in the United States, electric cars are heavily subsidised directly and indirectly.

One can only conclude that the case for subsidising or otherwise promoting electric cars in New Zealand is dubious in the extreme and the government policy is not founded on careful research.

Electric cars are less convenient and, in the long run cost about the same as conventional cars. They provide a small reduction in carbon dioxide emissions at a very high cost.

If many governments around the world decide that global warming is not a threat or that the carbon dioxide reduction of electric cars is not worth the cost and withdraw the subsidies, then the electric car industry could die.

This from Mercedes CEO Dieter Zetsche: “Manufacturers will not see a return within a reasonable time on the billions they’re investing now in electric cars…. You can reasonably say that nobody today is making a battery-powered vehicle that’s economically viable in its own right.”

NZ should wait until the technology improves and the economic advantage becomes substantial. Nobody knows when – or if – it will happen.