So, while EVs are clearly the technology of the future, for the time being hybrids (whether serial or parallel, plug-in or not) are still cheaper and more popular. And since we must cut emissions as rapidly as possible, we should encourage any electric car, hybrid (HEV) or plug-in hybrid (PHEV) or full-on electric (EV).
The price gap between hybrids and the un-hybrid version of a car model seems to be low (see Toyota's biggest selling hybrid isn't the Prius)—just US$ 2,200. And that will deliver a 30 to 40% cut in emissions.
Here's the 2019 pricing of the Hyundai Ioniq in the US:
Plug-in Hybrid $25,350
Let's assume there were a Hyundai Ioniq without an electric motor, an "un-electric" as it were. Using the Corolla price gap, it would cost, say $20,000. This means that the full-on electric would cost roughly 50% more than the un-electric, the plug-in hybrid 25% more. Even though both the plug-in hybrid and the full electric will be cheaper to run than the un-electric, the sales of these cheaper electric versions of the Ioniq still wouldn't replace sales of the un-electric, because ppl have to find the up-front cost of the car, whereas the petrol costs are spread over its lifetime. You can lease a car, but not everyone is able or willing to do that, and HP requires a deposit and the costs are still mostly up-front.
So, what to do?
Let's suppose we gave a subsidy of $2,500 to all electric cars. Using the Ioniq as an exemple, that would remove the up-front cost disadvantage of the HEV, reduce it for the PHEV to where the HEV's is today, and reduce the cost premium of the full-on EV relative to the un-electric to 37% from 50%. With a $2500 subsidy, rational consumers would buy electric. At first, most would buy the simple hybrid, though some would buy plug-in hybrids, and a few would buy the full EV. Emissions would fall by at least 40% as the car fleet transitioned.
I don't know how much the Ioniq EV's battery bank costs, but the petrol engine + gearbox + radiator + petrol tank must cost more than an electric engine—look at the small gap between the HEV and the un-electric, which represents the addition of an electric engine plus a small battery. This means the Ioniq's EV battery bank costs, say, $12,000. In five years' time, given that battery prices are falling by 20% per annum, it will cost just $4000, so the cost of an EV Ioniq will be close to the cost of the HEV, and below the cost of the PHEV ('cos you'll only need one engine). At that point, the subsidy will encourage ppl to buy the 100% electric car instead of the HEV.
Eventually, the EV would be cost competitive even without subsidy. On the Ioniq's current pricing, EVs will equal the cost of an un-electric in 8 years (longer than I had thought—I've been estimating 2023 or 2024, but this suggests 2028). The trouble is, we haven't got 8 years to waste. We must electrify our car fleet as soon as we can.
Instead of a subsidy, we could set rising targets for electric (of whatever kind) sales as a percentage of total sales, starting at 10% and increasing each year by 15%, so that by 2027 the EV/HEV/PHEV target would be 100% . It works like this. If a car wholesaler/manufacturer reached their target, there would be no penalty. If they didn't, they would have to buy points from those who have. Let's say the target is 10%, but they only reach 8%. They'd have to buy points equal to 2% of their total car sales. If they exceeded the target, they would have surplus points available for sale. But unlike the Californian and Chinese schemes, under my scheme, the manufacturer would earn 1 point for each electric car, whatever its type, rather than 1/4 point for an HEV, 1/2 a point for a PHEV and 1 point for an EV*.
The Californian and Chinese EV targets encourage sales of EVs over PHEVs and PHEVs over HEVs, by giving more points to the EVs than lesser electric cars. But that distinction is prolly unnecessary, and may slow the uptake of electric vehicles. As EV costs decline, they will automatically be chosen over HEVs and PHEVs. A target/subsidy which simply rewards buying an EV of whatever kind would lead to a much bigger take-up of electric cars than one which rewards EVs only, because hybrids are only a little more expensive than un-electrics. As battery costs decline over the next 7 to 8 years, sales of full-on EVs would rise progressively, until 100% of electric sales are made up of EVs. This would mean that we could start cutting emissions from transport now, not in 5 or 7 or 10 years while we wait for EVs to become cost competitive.
If at first electric sales are mostly HEVs or PHEVs, it wouldn't matter, because each year emissions of 1/12 of the vehicle fleet (assuming a 12 year car life) would fall, by an increasing percentage, as the electric target bit deeper. After 6 years, emissions of an additional 1/12th of the total car fleet each year would fall by 40%, rising progressively as EVs took a larger and larger market share. This would mean that total car emissions would be falling by 3% per annum from 2025 onwards, and this decline would continue and accelerate as the percentage of EVs in the mix rises. Over the first 10 years, the cut in emissions would come from hybrids, over the next 10 from a further step-by-step switch to EVs.
The world must, at a minimum, target a 3% per annum cut in total emissions if we are to avoid a climate catastrophe. By being less purist about HEVs relative to EVs, we can rapidly reduce emissions from cars (and implicitly, lorries and busses) starting now. Almost all manufacturers have one or other kind of hybrid in their line-up. And they have them now. The transition would be simple and easy. And from 2026 onwards, we could take the next step: going for 100% electric.
Two reviews of the Ioniq:
Hyundai Ioniq Hybrid 2019 review
* or rather 1 point for an HEV, 2 points for a PHEV and 4 points for an EV, which implies that the effective EV target is lower than the stated one.