So you have probably heard them by now – claims that electric vehicles pollute more than internal combustion vehicles (ICVs) that use petrol or diesel. This claim goes back a long way – back to a time when it was, at least, partially true. To understand the context of this discussion, I will first take you for a quick walk through some of the battery chemistries from our past:
Many electric vehicles that were developed during the technology’s long siesta used lead-acid or NiCad batteries, which weren’t exactly the nicest technology. Lead-acids, for example, are relatively fragile, and tend to leak minute amounts of lead acid – which can eat through the steel that makes up a large portion of the front end of your car. To prevent this, most vehicles have a tray made of plastic or stainless steel, in which the battery finds its home.
NiCad (Nickel-Cadnium) and it’s vastly superior child, NiMH (Nickel-Metal-Hydride) have problems of their own. NiCad isn’t suitable for deep-cycle applications, tends to get a bit too warm for comfort under heavy use, and has a pretty short battery life. NiMH is less prone to degradation over time, has an energy density 30-40% higher than NiCad, contains less toxins, has enough nickel inside to make it worth recycling, and has a higher temperature range.
Sounds great, right? Roll back a moment:
Both these types of nickel-based battery suffer from some rather problematic flaws. They are both very sensitive to deep discharge (being run until empty), require complex charging algorithms, are also sensitive to overcharging, and tend to heat up under load. They also have a high self-discharge (that annoying thing that makes a battery lose charge when it is doing absolutely nothing), and have a coulombic efficiency of only 65% (compared with 99% for Li-Ion batteries).
There was a third nickel-based battery chemistry as well – NiFe (Nickel-Iron). This was developed in 1899 by Waldemar Jungner as a substitute for lead-acid. It was later picked up by Thomas Edison, who further developed the technology. No matter how hard he tried, NiFe batteries were not efficient to charge, and had a major problem with ‘gassing’, formation of hydrogen within the cell.
Henry Ford played with this technology trying to build an electric counterpart to the Model T; so much so that it killed Ford’s original EV program. The batteries heated up excessively under heavy loads. Henry insisted on using NiFe batteries despite this, as they were developed by Thomas Edison, a close personal friend of his.
Apart from poor performance, NiFe batteries suffered from a prohibitively low energy density. They were, however, very resistant to overcharging, and lasted well in deep discharge conditions. The technology has found it’s place in the form of grid storage, thanks largely to their lifespan (around 50 years) and their low deterioration rate.
So, in light of the information above, why would anybody want to buy an EV?
The answer is simple: Tesla – let me explain…
In the past few years, the automotive industry’s newest successful startup has made significant changes to the way cars and batteries are made. Tesla was the first company to produce batteries in-house that are optimised for use in electric cars. These are Lithium-Ion cells in the 18650 form factor (about the same size as two C sized batteries end-to-end), which Tesla produces in the Gigafactory located in Sparks, Nevada.
Nothing special just yet, except that this factory produces them from raw materials. Regular battery cells go through several factories before being assembled into their own form factor. Tesla puts the raw materials into the factory, and it puts finished batteries out. This approach, called vertical integration, goes back to the founding of Ford, and was used for many years to produce cars all over America.
Tesla has revived the approach, offering reduced manufacturing cost, and more substantial control of their supply chain. It also allows them to make the batteries exactly how they want them. The results speak for themselves.
Thanks in part to Tesla, other EV manufacturers have raised their expectations of the battery cells provided to them. In turn, the EVs produced by these manufacturers have an operational battery life of well over 10 years. These batteries can then move on to home storage applications, where they can last another 10-20 years.
The environmental impact of Lithium batteries does exist, however it is not what most people think it is. You may have seen this Facebook meme:
The problem with this meme? It is complete nonsense! The “lithium mine” shown above is in fact a mine – one of the 10 largest in the world. It is the Escondida Mine in Chile. It’s sole product is – guess what – copper!
The bottom picture, meanwhile, is actually an oil sands site. A very clean one. According to Snopes, this is one of the cleaner “in-situ” oilsands plants. The majority of the operations of this type of plant are conducted underground. An open-pit oilsands facility is severely damaging – the oil sands site in Alberta, Canada was once located under 19,000 square kilometers of boreal forest. according to Desmog Canada.
So, oil isn’t clean, but skeptics expect us to believe that electric vehicles are much worse? OK, let’s do this.
The EIA reported that monthly oil production worldwide averaged 80,622,000 barrels per day. Each barrel is about 42 US gallons in volume.
42 gallons per barrel
3,386,124,000 gallons of oil per day.
A single gallon of gasoline takes about 6kWh of electricity to produce. So:
3,386,124,000 gallons of oil per day
6kWh of electricity
20.316744TWh (Terrawatt-hours) of electricity used per day.
Pretty extreme. This is enough to charge 203,167,440 Tesla Model S 100D’s – with the upside that they can achieve around three times the range using the same amount of electricity.
Let’s work this out per year:
20.316744TWh per day
365 days per year
7.41561156PWh (Petawatt-hours) of energy per year.
This is enough to charge over 74 BILLION Tesla Model S 100D’s per year. How many cars does it currently power? Between 1 and 2 billion. This also powers just over 51,000 ships and around 39,000 planes, many of which never get used.
Logic says that aircraft and ships will use more energy than cars – because they work much harder. But when the energy supply for the combined automotive, marine, and aerospace industries is that high – well, you get the picture. They don’t use enough to make up a real-world difference of over 72 billion cars.
The majority of the energy used by the oil industry is produced using electricity from coal and oil power plants, further compounding the problem. First of all, when oil is used to run a power plant, you end up using some of your product to enable you to make your product. That doesn’t help air pollution – and oil is being constantly transported to the world’s 636 oil refineries – most of which are powered by coal or oil – by ships that use what power source? Bunker oil. Which is even more polluting than petrol or diesel – the latter of which has come under fire recently for producing more toxins than petrol. This constitutes part of the infinite loop that is the oil industry supply chain. The oil is then refined using electricity provided by whatever happens to be the local source of energy. Ideally, it would be wind and solar. Realistically, it probably is not.
From the refinery, it is either a) shipped overseas for delivery to the petrol stations, or b) delivered to petrol stations on the same landmass by either truck or train. What do most trucks, and many locomotives run on? Diesel. We haven’t even got to fuel up our cars yet!
At the petrol station, the petrol or diesel is loaded into cars, and the owner goes inside to pay, or uses the app on his or her smartphone to pay for the fuel. They then drive off, oblivious to everything mentioned these last few paragraphs. As far as the average driver is concerned, petrol/diesel comes from the petrol station. If that were all there was too it, maybe ICVs could, possibly in some form of reality, be on par with EVs for environmental impact. But in this reality; it truly is impossible.
I won’t even get started on oil spills…