To fully understand the true environmental impact of electric cars, one has to examine the ‘generation-to-wheel’ CO2 emission cycle. Generation-to-wheel emission is zero if the electricity used to charge the car originates only from renewable energy such as wind. In Ireland, the share of renewable energy in the electricity mix was targeted to be 40% by 2020, and in 2021 we’re largely hitting that target. As a result, electric cars provide an opportunity to reduce CO2 in the transport sector through the electricity system.
From ground to vehicle
The first step in the process to assess the efficiency of EVs is how they are fuelled. In Ireland, 40% of our energy to the grid comes from renewables, and big steps are being taken with government targets to push that number higher over the coming decade, making it even more effective and sustainable to run our island’s fleet of vehicles on electrons rather than dead dinosaurs.
Ireland has an abundance of opportunity in this regard, from regular tidal forces (which work like clockwork, changing every 6 hours) providing effective energy generation through hydro-electric. Even on our milder East coast, we get a tidal flow of up to 3kts (as seen in the image to the left).
Moreover, an enormous amount of the Irish fleet of EVs charge at home primarily. Which provides two key opportunities for the country: 1) to provide better incentives to retrofit homes with solar PV, taking those cars off-grid & 2) to provide vehicle-to-grid services, taking pressure off of the grid at peak times when cars aren’t in-use (particularly at times when offices/factories are in operation and cars are idle). More innovation, investment and political will are needed there, and IEVOA will continuously lobby for these.
Per 100km, a conventional ICE vehicle requires up to 40kWh, compared to 8kWh in an EV to move itself.
So, if we can rely more on sustainable power sources in the grid, and even utilise EVs to take pressure off of that grid, we’ll be in a much more impressive situation from a climate standpoint than we are today. But even just having EVs instead of ICE vehicles provides enormous benefits to the environment.
Conventional cars with internal combustion engines are extremely inefficient with 80% or more of the fuel energy lost through wasted heat. Decades of cheap oil has led to a disincentive to improve car engine efficiency. It’s important to focus on this stat. Of all of the energy burned by an ICE, only a maximum of 21% of that energy is used to propel the car. An EV motor is far more efficient, putting up to 90% of it’s energy into moving the vehicle.
Building the car
Something we hear a lot by EV nay-sayers is that the construction of an EV is somehow worse than the construction of an ICE vehicle. There tends to be two primary arguments here: one, that it’s just as bad to make an EV as an ICE vehicle, & secondly, that dangerous, unethically mined resources are put into the compound of a battery.
Addressing the first question, this is a silly argument. There are literally less parts in an EV, mostly thanks to the lack of gearbox, engine, axle, etc. The reason we see so many innovative startups coming into the car space through EVs is that they are simpler to construct than old style cars.
The second question requires more thought. But ultimately, the argument comes down to the use of cobalt in batteries. Cobalt is mostly sourced through illicit mining efforts. And while battery producing OEMs are developing technology to reduce or remove the need for cobalt, it is still a huge part of the Lithium-ion packs we have today. For every 100kWh battery, there’s approx. 20kg of Co in there; which represents upwards of 20% of the weight of the battery.
The current forerunner to replace cobalt is manganese, which is cheaper, can be sourced ethically and is safer.
It’s worth noting that cobalt is also used in the dead dinosaur juice used in an ICE. Once that juice is burned into the atmosphere, it needs to be replenished. Cobalt in a battery is reused for the lifetime of the battery, which, with current battery management systems (BMS), could be decades without huge impact on performance. So the issue isn’t the use of cobalt per se, it’s where and how cobalt is being sourced. EV owners tend to be more conscious of where they source their juice, and so are forcing this agenda on OEMs.
Lifetime of the car
An EV has less moving parts than a conventional type of vehicle. There is, as such, a lot less that can go wrong. It’s why you see such a huge amount of original spec Nissan Leaf or Renault Zoe’s on Irish roads; they still run. Sure, they have old battery tech, but given most Irish car journeys are less than 5km, even a tiny battery pack could handle that.
The lack of moving parts in an EV means any maintenance is purely functional, and breakages are on common parts like bulbs or switches, rather than critical components of a gearbox, engine, etc. Moreover, an EV can be upgraded in future to a better battery pack, if needed. And several companies exist, including in Ireland, to extend the range of old EVs with newer technology.
As more modern battery systems are developed, it’s a lot easier to swap the battery pack in an older car as the basics are the same as any electrical device. Assuming the cables can be connected, no interruption needs to happen to the internals of the cars systems (cooling systems, electrical devices, etc.). This means a much more elongated lifecycle of a car, with the added benefit of recycling the older batteries as they become more redundant. A lot of older batteries are being recycled to create completely new, high-density batteries. Or in many instances, they’re being reused to have lower capacity battery storage for homes, used to take the home off-grid, heat water, etc.
Needless to say, outside of damage, rust or similar, an EV will almost always outlast an ICE, and even maintain its performance.