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  • MilesDriven

Passenger Vehicle Emissions, today and tomorrow.

What difference will a day make?

Rain drops cars

Today you can walk into a car dealership and buy a vast variety of different cars, from pure electric, to hybrid, to hydrogen-electric, all the way on to the more conventional petrol and diesel engines. In a decades time, the latter options will no longer be offered in some countries. This is due to a war on global emissions by governments that are desperately trying to find ways to reduce their carbon footprint as quickly as possible as they make legally binding promises on reducing their national emissions.

All this has heralded in the electric car, with startup tech firms becoming billion-dollar companies and legacy automakers removing large swathes of their production tooling and refitting them from engine building, to battery manufacture.

There are pluses and minuses to a switch for electric vehicles, but we will leave the preference of power delivery and driver experience at the door and tackle the bigger question. Are we concentrating our efforts on the easiest target, or the one that will make the biggest difference?

To break this down we will look at several aspects of global emissions caused only by passenger vehicles. The reason we are targeting passenger vehicles in this article is to separate them away from larger vehicles which may be harder, or less viable to switch over.

First, the problem, finding the emissions caused by passenger vehicles alone for the entire globe is more challenging than expected as most statistics either put 'ground transport' meaning everything from Heavy good vehicles, to motorbikes, and others quote 'transport', meaning planes, ships, and everything that rolls on wheels. Statista puts the figure of passenger vehicles (with some additional calculations) at around 12-14% of total global emissions, this will include taxis, but not buses.

We will use the high end of the estimate so that everything can be considered in a worst-case scenario.

There is a second problem, most reporting on transport emissions begins with a claim that any motoring enthusiast or casual observer of traffic will find hard to reconcile. This is that vehicle emissions have been near stagnant since the 1990's. The reason this is claimed is largely due to the ever-growing number of people that can afford personal transport, whilst the vehicles we actually buy have become a lot more fuel efficient and reduced their pollution significantly, we simply buy more of them. To put the figure another way, it would be similar to saying that electric car emissions are growing each year, a true statement, each year more electric cars are sold than the year before. The energy provided for those cars isn't switching as fast as the market is growing and so more power generation from fuel sources that are considered non-renewable, or 'unclean' are growing. The plan is that whilst that may be true for now, in time the power generation will become largely renewable, or 'clean' and so the problem will go away, but it is still unhelpful when discussing statistics.

The third problem is that the growing market for cars isn't occurring in the wealthiest nations, in fact, younger people are putting off buying a car for much longer than their parents did. The growth is centred in areas of the world that are transitioning, think African nations, South East Asia, India, China, and pockets of South America. So what's the problem? Look in the cities and towns of these growing nations and many vehicles are older, much older, and will likely be used until their odometers flip around back to 0 again or the wheels rust off. This may seem an insignificant point, but if we are going to consider this as a global issue, we must look at a global problem, the largest vehicle uptake is happening in nations that have been buying older cars or cheaper vehicles that are not creating the much smaller footprint of their newer stablemates. No one will begrudge them of this, if someone in Morocco just got the first car they have ever owned and it is a thirty five year old Toyota then we should be happy for them, after all, that is what prosperity and quality of life increases are all about. The trouble is that for the global emissions figure it leaves the worst emitters in with the least and wraps them all in a big bow. Buying a brand new Volkswagen Polo with a petrol engine shouldn't be seen as contributing to the 14% of global emissions from cars, but actually seen as dragging down the global average of emissions, if millions of people switched to a new car tomorrow that 14% would likely drop to 13%, a small margin, but every little helps. (Leaving aside the emissions caused to create those new cars, as anything to do with climate, the sum becomes more complex the more you try and figure it out.)

Now we know the problem, what is the current answer?

Most people will say, battery technology, but we need to take a step back first.

Concrete alone emits 30% of global emissions, electricity production accounts for 25% of global emissions according to the EPA. The internet accounts for roughly 4% of global emissions and just the production of mobile phones accounts for roughly 1%. We need to use the internet, we need electricity, and there is no question that concrete is necessary, and smartphones have changed the way we interact so much so it would be difficult to think of a world without them.

But just put into context, 60% of all global emissions are those four industries. This brings a big question, cars have been improving year on year when it comes to their carbon footprint, as well as reducing other harmful gases. In 10 years, assuming we kept building petrol cars, possibly hybrid so that the most energy-intense (moving a car from standstill) is reduced, would cars naturally go beneath 10% of global emissions. Then there is an even greater question, during the pandemic we saw several different industries retool to make everything from masks to medical equipment, would it be possible to use some of their capacity to clean the electricity production and innovate concrete to reduce emissions rather than switch from combustion engines to making batteries? Herein lies the problem, we currently view cars as global emitters and believe that by switching we can reduce the impact on the earth, but electric cars need to be powered by something.

Is there an alternative solution and why do cars get so much attention?

The system for motor manufacturers is one of trade. A company that makes just petrol powered cars, think exotic sports cars, for example, can buy some 'tokens' from an electric car company and bring their average fleet emissions to within the allowed amount, and continue selling big powerful engines. What if instead of having to trade with car companies they were forced to trade with electricity providers or concrete manufacturers? The incentive would be given to those industries to clean up their emissions faster, whilst the fossil fuel powered cars become less and less polluting, not forgetting that it is the fuel, not the engine that has always been the problem with passenger vehicle emissions. We know that cars don't need to run on petrol or diesel, especially newer cars that can run on ethanol, or man-made petrol, the latter releasing just water, but being very extensive and challenging to make. Toyota has proven that it is possible to make a combustion engine run using hydrogen, an abundant and clean energy source, and JCB have bet their future that heavy industry won't use batteries but instead large combustion engines that simply burn hydrogen, meaning buildings could soon be excavated and built with zero emissions coming from the tailpipe of the machinery.

Are we looking in the right place?

A lot is made of electric cars, and they are no doubt more efficient and easier to maintain and use than their mechanical sibling. However, it appears that a lot of money, resources and time is focused on resolving an issue that is unlikely to have a large impact on the overall global emissions. Assuming the figure is currently 14%, we know a large proportion of vehicles are being used in developing nations that will continue using combustion engines for decades to come as the cost alone will be a barrier to their use. If we go for a best-case of 50% of all global vehicles switch to electric within two decades, and this would be an incredible change, there would still be 7% of global emissions from cars that have a combustion engine. Then there will certainly be some emissions from charging the millions of electric cars.

Quick calculation time, currently there are 1.5 billion vehicles on earth, in our best-case scenario, there would be 700 million electric cars in 20 years. An electric vehicle (current average) uses 30kwh of power per 100 miles driven. The average mileage is 8,000 miles per year. (Apologies for those that use the metric system).

So the maths, but first, we are again going to apply a best-case scenario. Assuming electric cars advance quickly and the average halves to just 15kwh per 100 miles.

100 miles = 15kwh.

8,000 miles = 1,200kwh.

1,200KWH x 700,000,000 Vehicles = 840,000,000,000kwh.

Before we continue we should stress loudly, petrol/diesel also have emissions. The point of this calculation is not to paint electric cars in a negative light, but to see if they are likely to reduce the global pollution by a factor large enough to concentrate billions of dollars and millions of hours of resources and technical achievement that could be used elsewhere.

The UK's usage of electricity in 2020 was, 23,000,000,000kwh. 37% of this was from renewable sources. (8,510,000,000kwh).

The USA usage of electricity in 2019 was 3,950,000,000,000kwh. 15% of this comes from renewable sources with a place to make that 42% by 2050. (592,500,000,000kwh in 2019)

Note: We are not considering production Co2 for the purpose of calculation as all cars will have some Co2 from production, we do caveat that electric cars have a higher Co2 production for construction and so they can look cleaner in our calculations.

The figures are large, but the problem is clear. Would it not be better for the environment to concentrate all our efforts on electricity production alone for the next 20 years. If the USA were able to get to 62% renewable by 2050, that would be the same effect as replacing half the cars on earth with electric vehicles assuming electric cars get 100% more efficient. If the USA got to 82% by 2050, then electric cars dropping from the sky to replace half all the vehicles on earth today would be equal to that one country making its grid more renewable. This isn't mentioning the other giant electricity-generating nations, and the biggest of all, China.

Blue Toyota Mirai hydrogen

If we can simultaneously clean the electricity grid, reduce the Co2 from concrete, and have electric cars then we should. However, with such public attention, money, and resources focused on cars, you begin to wonder. What if the industry was left to make incremental advances as it has been doing, possibly even working with fuel companies to reduce the carbon in the fuel, and while doing so were putting the bulk of their resources to green incentives and buying green tokens from other industries which would increase their funding to bring the changeover forward.

Current world electricity emissions are 25% of the global pie of gases, which creates 23,989,000,000,000kwh. (27% of this is from renewable sources, not including nuclear as this is not an option for some nations)

If we replace half the cars on earth we will add another 0.03% of energy use (assuming electric cars double their efficiency, otherwise it adds 0.06%, still a tiny figure.)

On the other side, if car companies and other industries working on car batteries realigned to attempt to increase renewable sources of electricity. Making a 10% change in the next twenty years would negate any carbon emissions from the fossil fuel cars created.

The question remains of whether we can do both, whether there is enough money, resources, and willpower, to do this at the same time. If there is then we will truly be moving towards a cleaner planet, but if the choice is binary, we may be chasing headlines, rather than chasing change.

The alternative answer, hydrogen isn't quite as cool and sexy as the flashy tech giants backing electric cars, but when Toyota said they were looking at this as a real option for a combustion engine, and their Mirai Hydrogen-battery vehicle eliminates not only the charge time debate but adds no additional stress on the world electricity grid, could it be our forever answer for passenger car transport?

Lastly, we focused on electricity in this article, concrete, agriculture, and other forms of transport from shipping to aircraft could have been given as a comparison but were not. We also didn't touch on deforestation and coral reef and seafloor destruction as we wanted to stay close to the main topic of light vehicle transport. We hope that the article shines more light on lowering emissions in the most effective way, not just the most obvious way. Cars are a soft target, we see the fumes and the exhaust tips, but we shouldn't forget that just because something is right in front of us, it doesn't mean it should command all of our attention. Clean E-fuels, hydrogen, ethanol, and more efficient petrol and diesel all will reduce the current emissions by passenger vehicles, these shouldn't be overlooked just because we want to not see tailpipes anymore, a cleaner globe needs a cleaner mindset.


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