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We need your help to tackle the transport challenge!
Former Community Member
Our aim is not to “drain the ocean” in a few months but to add a voice of engineering insight to the debate, demolish potential myths and legends and suggest some sensible ways forward. We don’t expect to achieve pinpoint accuracy in our investigation, but we can be honest about that. We want to establish some genuine truths and point to where more work or funding should be focussed. We need more information and guidance to existing reliable reports and research on carbon in materials mining and manufacture, infrastructure provision, renewal and maintenance, and end of life recycling. Please share your thoughts by commenting below.
An interesting viewpoint on the comparison between EVs and ICE vehicles. The key assumptions are on the difference between the ‘official’ and ‘real life’ fuel consumption of ICE vehicles which is stated rather than justified and an ‘upstream’ figure for the preparation of petrol and diesel fuel. It also assumes that the CO2 footprint of electricity generation will not get worse over time. The difference between the fuel consumption figures requires significant justification. The figures achieved by motoring journalists are usually worse that the official figures as they will be ‘exploring’ the vehicles performance. The normal motorist may well achieve better figures than the official ones.
It also does not consider the very large amount of infrastructure required for charging EVs due to the low energy flow rate. A barrel of fuel, 159 l, is equivalent to around 1.7 MWh. A typical retail fuel dispenser delivers around 50 l per minute, so around 500 kWh per minute or 30 MW. A state of the art high performance charger with liquid cooled cable can reach 500 kW (500 A at 1000 V). A typical domestic charger installation might reach 7 kW, a basic plug in one 3 kW.
How many charging points do we need? One per EV if it is a typical domestic size? How much more distribution infrastructure do we need to install and maintain? How does this relate to the upstream figure used for ICE vehicles?
Do we need to replace each petrol pump with a number (how many?) of high power chargers to compensate for the low energy flow rate? This requires a different upgrade to the distribution system to be installed and maintained.
An interesting viewpoint on the comparison between EVs and ICE vehicles. The key assumptions are on the difference between the ‘official’ and ‘real life’ fuel consumption of ICE vehicles which is stated rather than justified and an ‘upstream’ figure for the preparation of petrol and diesel fuel. It also assumes that the CO2 footprint of electricity generation will not get worse over time. The difference between the fuel consumption figures requires significant justification. The figures achieved by motoring journalists are usually worse that the official figures as they will be ‘exploring’ the vehicles performance. The normal motorist may well achieve better figures than the official ones.
It also does not consider the very large amount of infrastructure required for charging EVs due to the low energy flow rate. A barrel of fuel, 159 l, is equivalent to around 1.7 MWh. A typical retail fuel dispenser delivers around 50 l per minute, so around 500 kWh per minute or 30 MW. A state of the art high performance charger with liquid cooled cable can reach 500 kW (500 A at 1000 V). A typical domestic charger installation might reach 7 kW, a basic plug in one 3 kW.
How many charging points do we need? One per EV if it is a typical domestic size? How much more distribution infrastructure do we need to install and maintain? How does this relate to the upstream figure used for ICE vehicles?
Do we need to replace each petrol pump with a number (how many?) of high power chargers to compensate for the low energy flow rate? This requires a different upgrade to the distribution system to be installed and maintained.
