Ireland can meet its ambitious carbon emissions reductions more easily by encouraging the take-up of hybrid cars, rather than cars powered only by batteries. That’s the claim of Emissions Analytics, an independent company which monitors vehicle emissions.
Established by Nick Molden, Emissions Analytics has been carefully checking and comparing the real-world emissions of cars since 2011, and it was data from them that partially blew the whistle on the 2015 diesel scandal. Now, in the wake of the announcement of Ireland’s plans to trim Co2 emissions by pushing the sales of electric cars, Molden claims that actually we can achieve more by keeping petrol and diesel engines, but using more hybrid technology.
“One of our biggest challenges is fleet turnover, with vehicles staying on the road typically for up to 12 years,” explains Molden. “It means that refreshing the entire fleet is a very slow process. Given reservations about current battery electric vehicles (BEVs), we require an alternative that will have a more immediate impact. Due to Co2’s long life in the atmosphere, a small change now is far better than a large change in the future. We need to optimise the use of the industry’s available battery capacity to facilitate a critical early reduction.”
The problem is twofold.
On one side, you have that slow, steady take-up of electric cars by the public. Even if sales accelerate dramatically between now and 2030, when the Irish Government wants to ban the sales of combustion-engined cars, that will still leave huge numbers of the circa-two-million vehicles on our roads still running on fossil fuel. Combined with that is the restriction on the availability of electric vehicles — battery production is still well behind what we will need to provide the numbers of electric cars being talked about, and supply of electric cars on the market is still tight. Huge investments are being made in battery factories, but they will take time to come on stream.
The hybrid advantage
Molden’s argument is that it’s better to spread that available battery-making capacity out over as many cars as possible. That means using smaller batteries per vehicle, which means going hybrid, rather than fully electric.
The figures are startling. Emissions Analytics used mild, full and plug-in hybrid real-world emissions test data, from both European and US vehicles, and comparing hybrids with their internal combustion engine equivalents. Using the company’s standardised on-road cycle, it determined the average Co2 reduction from hybridisation was 23 per cent for the EU and 34 per cent for the US, with an average of 30 per cent across all pairings.
Carbon reduction potential
The thing that Emissions Analytics is talking about here is the amount of carbon reduction that can be achieved with the current amount of battery production capacity. EA’s argument is that we can achieve more, faster, by spreading the available battery production out among as many cars as possible, rather than clustering battery production around a smaller number of high-capacity models.
EA has calculated the distance-specific Co2 reduction per unit of battery size (capacity), in grammes of Co2 per km per kilowatt-hour, for mild, full, plug-in hybrids and BEVs. The results indicated that mild hybrids are the most efficient way to reduce Co2, given limited global battery capacity. With a reduction of 73.9g/km/kWh, the technology was a clear favourite, with full hybrids coming in second at 50.5g/km/kWh. Due to their disproportionately large batteries, battery-electric vehicles (BEVs) were the worst of the available options, with a mere 3.5g/km/kWh reduction. The size of BEV batteries tends to be large to accommodate infrequent, extreme use cases – like high-mileage trips, not often undertaken by average drivers – and do not make the best uses of limited supply.
That, incidentally, is not taking into account how the electricity to charge the batteries is produced — it’s only looking at the localised tail-pipe emissions of the cars themselves.
A need for a policy redirection
It’s a piece of analysis that may well undermine some of the Irish Government’s planning around electric cars and their ability to reduce the country’s Co2 emissions. Currently, the Climate Action plan has it that we should be buying only electric cars (or at least, as the paper states, ‘zero-emissions capable’ cars which does potentially leave the door open to plugin hybrids too) by 2030, but the EA argument seems to be that we could do much more, and do it now, by focusing on mild hybrids and hybrids.
“Electrification has proved to be a promising path to reducing tailpipe emissions,” said Nick Molden. “The most extreme form of the technology – fully-electric vehicles – are often hailed as the solution. Paradoxically, full BEVs appear to be a highly inefficient way to achieve an urgent and meaningful Co2 reduction. With supply chain issues and consumer acceptance challenges including range and price, there is cause to investigate alternative use of our limited battery capacity.”
Diesel may not be dead.
Controversially, Molden went on to suggest that diesel power still has a huge potential part to play. He says that a mass switch to diesel power would reduce Co2 emissions by 11 per cent. Add a mild-hybrid system to those diesels, and you reduce another six per cent. A final swap to full hybrids would deliver an addition 16 per cent reduction for a 34 per cent total. Alternatively, switching directly from gasoline to gasoline mild hybrids provides an 11 per cent reduction, with a further 23 per cent from the move to full hybrid. Molden points out that as the EU’s 2030 target is a 37.5 per cent reduction in vehicle emissions, we can get almost all the way there, in theory, without a single battery-electric car being added to the mix.
Could hybrids be an answer?
“The ideal solution is an immediate transition to petrol and diesel hybrids, with a further decade spent refining the technology, infrastructure and battery supply chain to allow the adoption of BEVs,” concluded Molden. “By 2030, the EU and the US would have had another decade to develop expanded, cleaner electricity generation capacity, improving the lifecycle emissions of BEVs. Alternatively, by 2030 the availability and price of renewable energy may well fall to a level at which hydrogen fuel cells could be economically viable. These avoid the environmental and geopolitical issues caused by large-scale battery production and would likely offer even lower lifecycle emissions. The overall message is this though: it is paramount that governments and industry take into consideration real-world data when promoting technologies to efficiently reduce Co2.”
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