I enjoyed reading Greening your transport: Where does an electric car fit in? by Hubertus Jersmann. I would like to make some comments.
The Jersmann family are an illustration of car dependency even in our larger cities. Despite living only 3.5 km from the centre they have to drive large distances across town, partly as a taxi service for their children. This lifestyle is forced upon them because of the knock on effects on town development (was there a plan?) based on the car, and of course their social context determining among other things their children’s activities. By favouring walking, cycling and public transport they are the exception rather than the rule for urban Australians and setting a wonderful example that we could all follow. Even so, they probably spend a considerable time behind a windscreen.
I am impressed with the fuel use of the Leaf. This illustrates the efficiency of an electric motor over an internal combustion (or any heat) engine. Even so, most of the motive energy is spent moving the 1.5 tonnes of car rather than the people inside. Electric cars on average use 0.2kWh/km. (Internal combustion small car uses about 1kWh/km- David MacKay 2008). Electricity taken from the South-Eastern Australian electric grid has a greenhouse gas cost of 1kg CO2/kWh whether you are next to a South Australian wind-farm or in the centre of Melbourne. That’s because we are all connected to the same electricity grid. Therefore the Jersmanns are producing 0.2kg CO2/km. This is about the same as the greenhouse gas production by petrol cars (NTC 2012). Guessing they are driving the Leaf about 10,000km/yr, that is a cost of 2 tonnes of CO2 per year, or 20 tonnes for 10 years.
Furthermore, the embodied energy is considerable. Assuming a price of about $50,000 and the fact the Leaf is made in Japan where in general manufacturing creates 0.3kg of CO2e per dollar value, the embodied energy would be approximately 15 tonnes of CO2e. Although the cost in Japan would be much less than the price in Australia there is a lot of transport, handling and display greenhouse costs which have to be taken into account, most of it in Australia where the greenhouse gas cost of energy is 0.5kg CO2e per dollar (Seligman 2010). Therefore the “running” greenhouse gas cost of the Leaf and the embodied energy cost are roughly equivalent. So with all these assumptions and simplifications the Jersmann family are producing in very approximate terms 3 tonnes of CO2 per year with their Leaf car transport. They may well be producing less with a cheap small Asian car the same size as the Leaf taking into account its embodied energy (reflected by its cost). Of course this does not take into account the future increasing efficiency of electric car manufacture and developments in battery storage, and the replacement of fossil fuel electricity generators by renewable energy. It also does not include the reduction in pollution in the city (and its transfer to the neighbourhood of the fossil fuel power station).
An alternative solution to buying yet another car, albeit low in financial and environmental running costs, would be membership of a car share organization. There would have to be forward planning to book the car and travel to the car, both reducing the urge to use the car as the default transport solution, and favouring walking, cycling and public transport. Similar considerations would apply to car pooling arrangements. An added advantage of the car share is the availability of different types of cars including small hatchbacks, electric cars, utes, people movers, etc. (Go Get).
Australians spend several hours per week behind windscreens. They also spend several hours per week working to purchase and keep their car running, let alone the enormous physical and social infrastructure costs absorbed by the tax payer. Adding all the time on the job earning this money as well as the time using the car and dividing the result into the distance driven, “cyclists in Melbourne or Sydney who can average around 15km/h would be effectively faster than a motorist on an average income in the “fastest” new car (that is, the one with lowest operating costs). In New York, cyclists would need to cycle at only 9 km/h to be effectively faster than a car. In London, 7 km/h would place cyclists ahead of the fastest new car.” (Tranter, 2012). (This method of calculation is however fraught with practical difficulties. One frequent reason for the extra travel is to provide a taxi service for the kids to go to distant venues. The alternative of sending them off on a bicycle, regardless of the “effective” speed, would for most mums be considered an unacceptable risk even if the kids were willing to do it- a town physical and social planning and failure. The practical alternative might be having kids activities in your neighbourhood.)
Considering that the main intrinsic exercise left in our modern Western urban lives is moving around, cars cause an enormous amount of physical inactivity, a major risk factor in our most common non-communicable diseases. So much more than electric cars, walking the talk for DEA doctors is literally walking, cycling and using public transport as well as advocating for social and physical structures that support this lifestyle
John Merory, Victorian DEA subcommittee member
MacKay, D. 2009. Sustainable energy without the hot air. UIT Cambridge Ltd.
National Transport Commission. March 2012. Carbon Dioxide Emissions from
New Australian Vehicles 2011- Information Paper
Seligman, Peter. Australian Sustainable Energy By The Numbers, 2010 www.energy.unimelb.edu.au/files/site1/docs/pubs/Australian_Sustainable_Energy-by_the_numbers3.pdf
Tranter, Paul. The Conversation, 15 Oct 2012.