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As I wrote back in December last year, my first commandment of climate change is ‘Don’t take carbon atoms out of the ground and put them into the atmosphere’. Taking oil out of the ground and burning it is a very efficient way of breaking that commandment. Internal combustion engine (ICE) powered cars are excellent devices for burning oil and putting the resultant carbon atoms into the atmosphere. Transport accounts for 21% of New Zealand’s annual greenhouse gas emissions. Making the next vehicle you buy an electric vehicle (EV) should, all else being equal, go a long way to avoid breaking this first commandment of climate change. But not all else is equal, is it?

What I want to do in this piece is to consider some of the criticisms that are levelled against the uptake of EVs, and potential answers to those criticisms.

 

Problem #1 - Electricity supply source
If New Zealand were to shift its entire vehicle fleet to EVs, and we would need to build a couple more coal-fired power stations to generate the electricity needed to run the fleet, that would be a little pointless. If you’re going to be taking carbon atoms out of the ground in the form of coal for that purpose, you might just as well have taken them out in the form of oil and made the oil into petrol.

Potential solutions: An obvious solution is to grow New Zealand’s renewable electricity generation capacity at a rate that keeps up with the increasing demand generated by the shift to an EV fleet. The government has an ambitious goal of having New Zealand’s electricity generation being 100% renewable by 2030. This may depend in large part on the construction of the Lake Onslow scheme to ensure that we can make it through a dry winter where the hydropower generation capacity is diminished. An update regarding that scheme appeared on the front page of the 31 March edition of ‘The News’. But the Lake Onslow scheme doesn’t represent a new source of electricity, it’s just a big battery. The question remains, therefore, whether the growth in renewable electricity generation will be sufficient in the face of a large-scale shift to an EV fleet? That’s a challenge for us individually and as a country.

Having an EV can boost electricity supply resilience. Over the last three months, my house has been using, on average, 7.5 kWh of electricity each day. This is quite low because I have solar PV on the roof generating quite a lot of electricity. But it’s annoying that I must buy any electricity at all; during summer I generate way more than I use. Being able to plug my EV into my house and to have the 40-kWh battery in my car store electricity when it is being generated and then used by the house during the night or on cloudy days when the solar panels can’t keep up, would go a long way to further reducing my electricity demand. I have heard that the technology for plugging my Nissan Leaf into my house electricity system so that it can use the car’s battery as storage is coming this year. Now of course you will have noticed that if I’m using 7.5 kWh per day that a 40-kWh battery can only carry the house for 5 days. I am looking forward to seeing how things go through the coming winter to see if there is enough coming off the solar panels so that, together with battery storage, it would be sufficient to fully cover my electricity use.

The bottom-line here is that coal-fired electricity generation in New Zealand is primarily required to cover short-term peaks in electricity demand. Having EVs connected to houses, even if those houses have no solar PV, could be very useful in smoothing out electricity demand such that we never need to burn coal.

 

Problem #2 - Infrastructure
It has been said that an EV vehicle fleet can never work because the infrastructure needed to charge them all (lots of charging stations) aren’t available. I suspect similar things were said when electricity was proposed as a way of providing energy - “This is never going to work! How are you going to get the electricity from where it is generated to everyone’s home? Don’t tell me you’re going to string out wires everywhere. That’s simply ridiculous!”. Or maybe the same when ICE-powered cars were invented - “But where do I get the petrol for my car? There aren’t any petrol stations!”.

Potential solutions: I acknowledge that a lot more charging stations need to be built, but, personally, I don’t see the lack of many charging stations being a deal-breaker for shifting from ICEs to EVs. Most people I know who own an EV charge them up at home. Other than a few farmers with a diesel tank on the farm, nobody I know who owns an ICE vehicle has a fuel pump at home. If anything, EVs require less infrastructure than ICEs. I would like to see 10 EV charging stations up and down Tarbert Street (and other main streets in Central Otago towns), right outside the shops. Yes, they would each need a 50-kW power supply but surely that’s doable. Alexandra is a good spot to charge up an EV when travelling from Queenstown to Dunedin, and it takes around 30-40 minutes for a full charge. Just the right amount of time for a hot chocolate and a muffin or browsing around some shops that are right where you parked to charge up.

 

Problem #3 - Embedded carbon
I have heard the criticism made that while EVs generate no greenhouse gas emissions when they run, significant greenhouse gas emissions are incurred in the manufacturing of an EV (so-called ‘embedded carbon’). Of course, this is true, but it doesn’t present an apples-to-apples comparison. The key question to ask is: over its full lifecycle, from manufacturing to being used to being disposed of, which results in the greater quantity of greenhouse gas emissions, an EV or an ICE? I don’t know the answer but, setting aside the issue of the batteries (more on this below), an EV requires less metal (as there is no large engine) compared to an ICE and generates no greenhouse gas emissions when running. That said, EVs require about three times more copper than an ICE because of the use of copper in the electric motors – global demand for copper is expected to increase threefold by 2050 as a result.

Potential solutions: It would be ideal if all cars, both EVs and ICEs, could be manufactured 100% sustainably, e.g. using only recycled materials and renewable energy. I believe that is possible and impressive developments are underway towards achieving this goal.

 

Problem #4 - Heavy metals
This is the biggie (at least for me). The lithium-ion batteries found in most EVs are expensive to produce, heavy and only last for 5-7 years before their performance starts to degrade. EV batteries also require lots of heavy metals, some of which are mined in appalling conditions. In the case of the cobalt required to manufacture lithium-cobalt-oxide batteries, 60% of the world’s supply comes from the Democratic Republic of the Congo where large numbers of unregulated mines use young children as miners. Local water supplies are further contaminated by the discharge of waste from nearby mineral processing plants. The lithium required for EV batteries is found mainly in Australia, South America, and China where the mining of lithium is linked to a variety of negative environmental impacts. In South America vast quantities of water are pumped from underground as part of the extraction of lithium from ore. This use of water results in lowering of ground water levels and the spread of deserts.

Potential solutions: One possible solution is to make EV batteries much smaller and have them charged at regular intervals, e.g., every few kilometres by way of induction coils in the road that charge the battery as you drive along in much the same way as a wireless charger charges your mobile phone. There is research currently underway in New Zealand at the Robinson Research Institute at Victoria University of Wellington, funded by the Ministry of Business, Innovation and Employment, to develop this capability.

There is also a massive and growing need for better battery technology. Zinc-air batteries can store six times as much as lithium-ion batteries but currently are not rechargeable. However, last year a paper published in the journal Science reported on research that would allow a zinc-air battery to be rechargeable.

Regarding alternative sources for the copper, lithium, and cobalt required to manufacture EVs, we can look to alternative sources such as metal nodules which litter some parts of the ocean floor. These nodules, about the size of a potato, are rich in copper, cobalt, manganese and other metals. But can these nodules be harvested in a way that doesn’t cause further degradation of ocean ecosystems? A less likely (at least for now) solution is to mine near-Earth asteroids for these metals. About 10% of near-Earth asteroids are essentially massive mountains of nearly pure iron and nickel. Companies are starting to pop up (and then back down) to develop the technology required to mine near-Earth asteroids. I would feel a lot better about mining an asteroid to create my EV and the batteries and motors it needs to run, than destroying ecosystems to extract those same resources from the planet we are living on. Of course, that begs the question of the greenhouse gas emissions and other potential environmental costs of space flight.

 

Summary
So, are EVs the panacea for climate change that some hope for and/or claim? Given the processes currently used in their manufacturing, probably not. Does that mean you shouldn’t buy one? Certainly not. My approach as been to pick the lesser of the two evils, i.e., selecting an EV over an ICE, and then doing whatever I can to support continued development of the technologies on which EVs are based to minimise their environmental impacts.

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