Sir, – As a society, we all need to strive toward not using cars and this is the best way to reduce our environmental impact. And if a car is necessary, keeping the one we have already is the next best way. Finally, if the previous two options are not available, we can start to consider the points put forward by John Leahy (Letters, December 16th), which while correct in some ways, give quite a simplified view.
First, he is correct that wind is intermittent; however, he then highlights periods of extremely low wind during the summer, and caps the penetration at 50 per cent. In recent times, due to innovations at Eirgrid and the installation of a flywheel at Moneypoint, the grid regularly exceeds 50 per cent wind generation, hitting 56 per cent for the month of February 2022. It would probably be fairest to look at the annual average penetration which was 38 per cent in 2020, 31 per cent in 2021, and 35 per cent year to date in 2022, according to the Sustainable Energy Authority of Ireland. Even the three summer months that were highlighted as extremely low have an average renewable penetration of 24 per cent across the period.
Second, this renewable penetration number can be changed over the lifecycle of the EV. For example, when (eventually) offshore wind farms are deployed in Ireland, the penetration will increase, and intermittency will decrease due to more consistent sea breezes and bigger turbines. This will only improve the carbon footprint of the car. A similar petrol car does not have the opportunity to improve its carbon footprint once it is on the road. Furthermore, wind generation overnight is frequently curtailed because of lack of demand for electricity. If there were a fleet of EVs charging overnight to avail of this power, again the renewable penetration would increase.
Third, despite looking on the internet, I couldn’t find the Volskwagon/Audi report referenced, but I would immediately question if it includes the full carbon footprint of the supply chain for fossil fuels, ie the manufacture and fuelling of the oil tankers (marine and road) for the next 15 years. A similar report by Volvo (available from Volvo’s website) analyses the total carbon footprint of their XC40 (petrol) and C40 (EV). From manufacture to 200,000km on the odometer, the total carbon footprint was 59 tonnes for the XC40 and 27 tonnes for the C40 (with 100 per cent renewables).
In a scenario of approximately 20 per cent renewables, the carbon footprint of the C40 increased to 42.
In summary, at 20 per cent renewable energy, the total carbon footprint was still 29 per cent less. Referring to Ireland’s electricity mix discussed above, the carbon footprint would be lower than 42, so carbon savings are greater than this 29 per cent.
Finally, this all assumes that zero tailpipe emissions are of negligible benefit. However, this is patently not the case. Removal of fumes from the streets we live in, and outside the schools our children go to, will have a significant public health impact. And that extends to more than carbon, that is across the full suite of exhaust gases including nitrogen oxides, particulate matter and sulphur oxides. – Yours, etc,
CHRIS CUMMINS,
Dublin 16.