top of page

Electric Cars - Conclusions


On the Tesla Itself

Range is a big problem and for many this would render it more or less impractical as a main car. Add in the purchase price of around £55,000 (after the £5000 discount so generously gifted by the UK government and paid for by the rest of us) and it looks even less sensible. Other EV cars are also expensive. The basic ICE Ford Focus is around £16,000, the electric version is £31,000 (£26K after the discount) and will have a range of less than 100 miles.

There is the possible issue about resale value. Tesla give an 8 year warranty on their battery – if it fails after it could cost something around £17,000 for a replacement. No doubt battery costs will reduce in real terms, but this alone could possibly render an older secondhand Tesla (with no battery warrantee) as virtually worthless.

The life of a car is an important consideration when looking at its lifetime CO2 impact. The CO2 generated by manufacture of a car is hard to pin down, but would appear to be of the order of at least 6000 to 10000 kg for an ICE based vehicle. By comparison, at 7900 miles per year, and a 10 year life, then an average UK diesel car would generate around 19,600 kg CO2 in exhaust emissions.

It will be interesting to see how the Tesla model 3, due out mid 2017 and aimed to be much cheaper than the model S, measures up.

On EV’s in General

In the UK, electric vehicles are not as green as they might at first appear. The CO2 emissions from charging up an EV in the UK are similar in scale to those from modern diesel cars.

Even as the production of electricity is decarbonized, the fact is that until and unless there is excess zero carbon electricity over and above that needed to satisfy non-transport electricity demand in the UK then charging an EV will always result in power generation from a gas fired generator.

There may well be a place for EV’s for short trip urban driving, but until the range can be extended to around 300 miles (preferably more) then they will struggle to find acceptance for the drivers who do not just drive in congested cities.

In terms of CO2 emissions EV’s used for combined driving are worse than modern small or some medium-size diesels. Moreover, for this type of driving pattern running diesels on bio-derived fuels such as biodiesel can deliver significantly lower nett CO2 emissions than an EV. Using the Tesla Model S as a yardstick, many, if not most, current diesel cars could match or beat the CO2 emissions of an EV if run on bio-diesel.

The real world energy usage of EV’s is not well defined, in particular the issue of ensuring that all losses are accurately accounted for, including those from transmission and charging, as well as losses from the charged battery.

EV’s are comparatively expensive, and rushing to electrify car transport implies massive investment to expand electricity production capacity. There might be better ways to spend the money to reduce overall environmental impact from energy usage. After all, private transport uses only around 20% of all UK energy

While there is little doubt that the battery technologies for EV’s will continue to develop, there is also little doubt that efficiency for ICE based vehicles will improve. Energy use can always be improved by adding extra cost and complexity, for example by shifting to lighter weight materials. Hybrid cars get improved performance in city driving by achieving more optimal engine operation. Alternative approaches such as the Peugeot Air Hybrid system also may offer a route to improved efficiencies for ICE vehicles.

References

1. https://www.fueleconomy.gov/feg/bymodel/2015_Tesla_Model_S.shtml 2. 3. http://www.renewableuk.com/en/renewable-energy/wind-energy/uk-wind-energy-database/ 4. https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/487856/QEP_final_Dec_15.pdf 5. http://www.shell.co.uk/motorist/shell-fuels/pump-pricing.html 6. http://www.biomassenergycentre.org.uk/portal/page?_pageid=75,163182&_dad=portal&_schema=PORTAL 7. Environmental Benefits from Driving Electric Vehicles? Stephen P. Holland, Erin T. Mansur, Nicholas Z. Muller, Andrew J. Yates 8. http://www.cleanenergypipeline.com/Resources/CE/ResearchReports/Offshore%20Wind%20Project%20Cost%20Outlook.pdf 9. https://en.wikipedia.org/wiki/Life-cycle_greenhouse-gas_emissions_of_energy_sources 10. http://www.ukconversionfactorscarbonsmart.co.uk/documents/2014%20Emission%20Factor%20Methodology%20Paper_FINAL-4Jul14.pdf 11. http://www.parliament.uk/documents/post/postpn_383-carbon-footprint-electricity-generation.pdf 12. https://www.teslamotors.com/en_GB/models 13. http://www.honestjohn.co.uk/realmpg/ 14. http://www.nissan.co.uk/GB/en/vehicle/electric-vehicles/leaf/charging-and-battery/range.html 15. http://www.renewableuk.com/en/renewable-energy/wind-energy/uk-wind-energy-database/figures-explained.cfm 16. https://www.zap-map.com/ 17. http://www.ref.org.uk/generators/group/index.php?group=TechCode 18. http://www.ukconversionfactorscarbonsmart.co.uk/ - DCFCarbonFactors_10_1_2016_213927.xls 19. Summary of Wind Turbine Accident data to 31 December 2015, Caithness Windfarm Information Forum 2015, caithnesswindfarms.co.uk 20. http://www.ref.org.uk/attachments/article/281/ref%20pr%2019%2012%2012.pdf (renewable Energy Foundation, 19/12/2012) 21. http://www.inference.phy.cam.ac.uk/sustainable/book/tex/sewtha.pdf

EV07-0116

102 views0 comments

Comments


bottom of page