Green Scene: The environmental impact of the move to electric vehicles

The ‘Green Scene’ Series on Newstalk is a weekly update on energy and environmental matters with Pat Kenny and MaREI Director Brian Ó Gallachóir.

On July 21st, 2021, Prof Ó Gallachóir discussed  the environmental impact of the move to electric vehicles and also if current extreme weather events around the world are due to climate change.

1.      Are Electric Vehicles bad for the Environment?

1.      The answer is NO, when compared with a petrol or diesel car and YES, when compared with no car.

2.      Why NO, when compared with a petrol or diesel car?

a)     Electric Vehicles do not burn fuel so no carbon dioxide emissions and no air pollution.

b)     However the electricity used to charge EVs may be generated by coal, or gas, or wind, or solar – so there may be indirect CO2 emissions associated with EVs.

c)      That said, EVs are significantly more efficient than petrol or diesel cars (about 4 times)

d)     So, even if you’re fully using coal fired electricity, EVs would likely win on CO2 emissions.

e)     Based on Ireland’s electricity fuel mix, a petrol car will likely generate twice as much CO2 as an EV

f)      But here we’ve compared car usage – what about embodied emissions associated with the manufacturing of the cars?

g)     Here EVs will typically fare poorly due to the energy intensive mining processes required to extract lithium, nickel, cobalt and graphite (used in the batteries)

h)     Also, the battery production is generally an emissions intensive process

i)       Comparing on a life cycle basis, it is estimated that EVs outperform petrol and diesel cars and will have ‘paid back’ their higher manufacturing-phase emissions after about 2 years in the EU.  

j)       As the emissions associated with electricity generation reduce (due to increasing wind and solar), EVs further and further outperform petrol and diesel cars on CO2 emissions

3.      Why YES, when compared with no car?

a)     All cars are ‘bad’ for the environment – it’s best (but not always practical) to use no car

b)     In addition, replacing petrol and diesel cars with EVs is not the solution – for one thing it does not address traffic congestion

c)      As pointed out recently by my colleagues Dr. Hannah Daly, ‘Relying on electric vehicles to solve the transport emissions crisis is akin to tackling obesity by calculating how much salad to eat while still overwhelmingly consuming junk food’

d)     Cars take up a lot of space (and spend about 95% of their time parked).

e)     A key focus is required on reducing the number of cars burning petrol and diesel, and minimising their use

f)      More walking, cycling and public transport are required in addition to EVs.

2.      Are the current extreme weather events due to climate change?

1.      We know from scientific analysis that climate change is happening

2.      We know that one of the impacts of climate change is the increased occurrence of extreme weather events

3.      But do we know if the current extreme weather events are due to climate change, or could they be part of the naturally occurring weather variations?

a)     A recent paper in the journal Nature concludes that ‘Climate change made North America’s deadly heatwave 150 times more likely’

b)     The researchers concluded that the devastating heatwave that struck parts of Canada and the United States late last month would have been extremely unlikely without global warming

c)      “This heatwave would have been virtually impossible without the influence of human-caused climate change,” says Sjoukje Philip, a climate scientist at the Royal Netherlands Meteorological Institute (KNMI) in De Bilt and a co-author of the analysis.

d)     “It was probably still a rare event, but if global warming might exceed two degrees, it might occur every five to ten years in the future.”

e)     The record-breaking heatwave lasted from 25 June to 1 July, and affected large cities that rarely experience extreme heat, including Portland, Oregon; Seattle, Washington; and Vancouver, Canada.

f)      More than 500 excess deaths and 180 wildfires were recorded in the western Canadian province of British Columbia.

g)     The region’s peak temperature of 49.6 °C, recorded on 29 June in the village of Lytton, was the highest ever reported in Canada.

h)     Lytton’s inhabitants were evacuated before a devastating blaze almost completely destroyed the village.

i)       The analysis was more challenging than similar studies, including those on heatwaves in the past few years in western Europe and Russia, says co-author Geert Jan van Oldenborgh, a climate modeller at the KNMI.

j)       The peak temperatures observed were up to 5 °C higher than previous records in the region.

k)     These extremes made it hard to pin down precisely how rare a heatwave of such strength might have been in cooler periods of the past, and how often it might be expected to occur in the current climate, he says.

4.      What about the floods in Germany, and elsewhere in Europe, and Ireland’s current heatwave?

a)     Determining the role of climate change in last week’s relentless downpours will take at least several weeks to research

b)     “Floods always happen, and they are like random events, like rolling the dice. But we’ve changed the odds on rolling the dice,” said Ralf Toumi, a climate scientist at Imperial College London.

c)      A 1-degree rise in average global temperature increases the atmosphere’s capacity to hold water by 7%, climate scientists have said, raising the chance of heavy rainfall events.

d)     Other factors including local geography and air pressure systems also determine how specific areas are affected.

e)     The raft of climate policies proposed by the European Union this week was timely, aimed at slashing the EU emissions by 2030.

The REthink Energy series featuring Green Scene is supported by ESB and The Institute of International and European Affairs.