* Posts by Mark Tebbutt

5 publicly visible posts • joined 18 Apr 2007

Who are the biggest electric car liars - the BBC, or Tesla Motors?

Mark Tebbutt

combined cycle gas turbine

Electric cars cannot be beaten on tank to wheel (motion) efficiency or more appropriately battery to wheel for an electric vehicle. The Nissan Leaf battery holds about 24 kWh of electrical energy. 1 litre of Petrol holds the equivalent energy to 9.66 kWh and 1 litre of Diesel holds the equivalent energy to 10.72 kWh if combusted in a 100% efficient engine. The average internal combustion engine is around 35% efficient the other 65% is waste heat and noise.

So the Leaf battery holds the equivalent of 2.5 litres of Petrol or 2.2 litres of Diesel for approximately 100 miles of driving. You would need a Petrol powered car to achieve 181.6 MPG and Diesel powered car to achieve 206.3 MPG to match the Leaf’s Tank to Wheel efficiency. Clearly there aren’t any fossil fuelled cars now or in the near future that come anywhere close to matching the said figures for the same size of vehicle.


Well to Tank, fossil fuel currently beats electrical power generation and transmission. The most efficient fossil fuelled power station available is a natural gas burning combined cycle gas turbine (CCGT) plant which can achieve efficiencies of around 60%. http://en.wikipedia.org/wiki/Combined_cycle#Efficiency_of_CCGT_plants . So with the transmission losses of around 6.5% only 56.1% of the energy in the natural gas is delivered to the charger. The oil companies quote a figure of around 81.7% for Well to Tank / Pump.

However the 56.1% efficiency Well to Tank for power generation is more than offset by the 3 times greater Tank to Wheel efficiency of the electric vehicle. As the grid starts to add more renewable and possibly nuclear power the said Well to Tank efficiency will increase making the electric car even more compelling. The electric vehicle is the only vehicle that becomes cleaner / greener with age as over time power generation is cleaned up.

The last 24 hours of electricity generation in the UK was provided by the following generation type. Data from my UK Energy i-phone app but ultimately from Elexon

Combined Cycle Gas Turbine 40.4 %

Coal 37.9 %

Nuclear 18.1 %

Wind 0.7 %

Pumped Storage 0.7 %

Non Pumped Storage 1.0 %

French Interconnector 1.1 %

Tesla motors explains all of the above far better than I have on their website at http://www.teslamotors.com/goelectric/efficiency.

Used electric vehicle batteries can have a second life to help store renewable energy and smooth out the grid. Vehicle 2 Grid might also become a reality in a the future. You could make money charging your car battery on cheap over night electricity and then selling it back to the grid during the day at a higher price. Although the number of charge cycles a battery pack can currenly perform would have to increase greatly to make it worthwhile without having too much of a negative impact on the battery pack lifespan.

The status quo will be more expensive in the medium to long term.

“"Britain has been given a second and final written warning by Europe to clean up London's air or be taken to the European court of justice and face fines of up to £300m.

The warning, sent today by the Environment commissioner Janez Potočni refers to minute airborne particles known as PM10s which are emitted by traffic and factories and can lead to heart attacks, strokes, asthma and lung diseases. According to the Mayor of London's Air Quality Strategy, particle pollution is responsible for over 4,300 premature deaths a year in London at an annual cost of up to £2bn. (The figure is drawn from a report commissioned by the Mayor of London whose full findings were not published.) London's air pollution levels rank as the worst in the UK and also among the worst in Europe."


"London air pollution 'worst in Europe'Britain faces court cases and unlimited fines after dangerous levels of minute particles breach EU levels"


London has already been warned to clean up its air quality or face millions in fines from the EU. London has been ranked as having the most polluted air of any city in Europe!”

Well I for one put a deposit down on Leaf on the 1st of September and will be trading in my Audi TT in when the Leaf goes on sale in March. We have recently installed 3.15 kWp of solar photovoltaic panels on the roof and have subscribed to a green electricity tariff for years. The tariff recently rose from 9.3p to 11.7p per kWh. I know the limitations of the car which I am willing to live with and work around by using the train or borrowing a ICE car for the occasional long distance journey. Living in the Chorley Lancashire area I think I have only driven the 240 odd miles to London a couple of times as the train is faster and far less stressful.

Billions of pounds worth of research is going into batteries which will double the range within 3 to 5 years. The current electric cars are a little better than the first mobile phones and they too like the early mobiles will advance at a similar rate over the next 10 to 15 years. The price of Petrol and Diesel is only going to increase as all the easy to extract oil has been extracted and as the world recovers from recession all those citizens of India and China will start to drive their first cars. Supply and demand.

The worlds fossil fuel industry is subsidiesed to the tune of $300 billion a year.

Diesels greener than electric cars, says Swiss gov report

Mark Tebbutt
Gates Halo

Ignorance is bliss and spin is power.

I have loved reading the register for years but most of the articles on electric cars and climate change seem to be extremely biased to the journalists point of view. Where has the impartiality gone?

Has anyone who read Lewis’s article bothered even to skim read the referenced report?


I just did and it seems Lewis has deliberately manipulated the facts to suit his preferred outcome. For instance in report there are two figures one for the each of the evaluation methods used. The first is the figure of 3.9L/100km that Lewis referenced and the second is a figure of 2.6L/100KM. The first figure only takes in to account the use of minerals and energy, while the second non reported figure also appraises toxicity to humans and ecosystems. Which is fairly relevant if you care about the health of your family.

“GWP, CED and ADP are driven exclusively by the use of minerals and energy, while EI99 H/A also appraises toxicity to humans and ecosystems.”

“Nevertheless, the operation of an ICEV alone causes impacts that are roughly just as high (CED, 92%; GWP, 125%; Figure 2) as the total environmental impacts of E-mobility (100%). A break even analysis shows that an ICEV would need to consume less than 3.9 L/100km to cause lower CED than a BEV or less than 2.6 L/100km to cause a lower EI99 H/A score. Consumptions in this range are achieved by some small and very efficient diesel ICEVs, for example, from Ford and Volkswagen (13, 39).”

So that’s 72.43 MPG just to be as efficiency as a Golf converted to a BEV on the current electricity generation mix or 108.65 MPG to achieve the same levels of efficiency and air pollution as a Golf converted to a BEV on the current electricity generation mix. I for one don’t know of any current or future production pure ICE car that will get close to the figure of 108.65 MPG. I think both figures would be even higher if the report used a car built from scratch to be a BEV (Nissan Leaf) rather than a conversion. Also over time electrical generation will become cleaner and more efficient. The UK has a legal target of 15% renewable energy by 2020.

“Propelling a BEV with electricity from an average hard coal power plant increases the environmental burden by 13.4%. On the other hand, using electricity from an average hydropower plant decreases environmental burden by 40.2%. This results in a decrease for the operation from 41.8% (UCTE mix) to 9.6% when charging the battery with electricity from hydropower plants.”


“The Renewables Obligation (RO) is the current main mechanism for supporting large scale generation of renewable electricity. Since its introduction in 2002, it has succeeded in more than tripling the level of renewable electricity in the UK from 1.8% to 6.64%1 and is currently worth around £1.42 billion/year in support to the renewable electricity industry.”

“Transport service affects the environment largely by contributing to global air pollution. PM10, SO2, and NOx traffic emissions contribute significantly to environmental problems such as acidification and eutrophication (SO2 and NOx), photochemical air pollution (NOx) or have adverse effects on human health, for example, cell toxicity, damage to genetic material by means of oxidative stress or by triggering allergies (PM10, SO2, and NOx). With respect to the LCI results for the pollutants PM10, SO2, and NOx, transport with a BEV leads to higher environmental burden than transport with an ICEV. However, the emissions caused by the production of the vehicle, in particular the Li-ion battery, are located in industrial areas where the population density is rather small. The releases of emissions from operation are prevalent in urban areas with a high population density. The NOx-emissions from an ICEV that originate prevalent from operation, consequently have a high damage potential to human health.”

Lewis also makes no mention of the concluding statement of the report that Li-ion battery production does not negate the potential benefits of the higher efficiency of BEV compared to an ICEV!

“All the facts taken together, the results of the LCA, the various sensitivity analyses, the modelling applied for EOL, the assumption for the used electricity mix, etc., suggest that E-mobility is environmentally beneficial compared to conventional mobility. The Li-ion battery plays a minor role in the assessment of the environmental burden of E-Mobility. Thus, a Li-ion battery in an BEV does not lead to an overcompensation of the potential benefits of the higher efficiency of BEV compared to an ICEV.”

I will be trading in my 226g/km (CO2) spewing steam age based tech Audi TT for a Nissan Leaf come March next year and I for one hope it will make future BEV’s cheaper. No one will need more than 637Kb of memory for a personal computer and ICE cars will still be around in 30 years.

Mark Tebbutt

Ignorance is bliss

Yeah just like there are billions of tons of CO2 in atmosphere and adding few more billion from the buring of fossil fuel and deforestation couldn’t possible hurt could it?

Porsche to challenge London CO2 penalty in court

Mark Tebbutt
Thumb Up

Sends a clear message to performance car makers to do better

Hopefully this will send a clear message to performance car manufactures that its time to abandon the dinosaur internal combustion tech (fossil fuels get it) and move to electric vehicles as they can provide better performance than a Porsche 911 for roughly the same cost www.teslamotors.com .

Critics point out that electric vehicles simply move the pollution to the power station. This is true but due to the efficiency of electric vehicles the amount of pollution per mile driven is greatly reduced and can more readily be tackled at a few dozen power stations than from millions of individual cars. http://www.teslamotors.com/efficiency/well_to_wheel.php

If an individual has a desire to drive a zero pollution car the addition of around 3KW of photovoltaic panels to their home would provide enough zero pollution electricity to drive 20,000 miles a year even in cloudy old Britain.

People who believe that modern car exhausts only emit CO2 and water are grossly miss informed. All car exhausts emissions are toxic and do damage to peoples health. A recent report by the lancet claims" Living too near a busy road could stunt a child's lung development, US research involving 3,677 children suggests." http://news.bbc.co.uk/1/hi/health/6297701.stm

Ethanol cars unhealthier than petrol ones?

Mark Tebbutt

Come the Revolution!

he focus on wind power as the only way to produce renewable carbon free electricity for battery electric cars seems a bit odd to me. Surely renewable electricity should come from multiple sources e.g. solar photovoltaic, wind, wave, hydro.

Bio-fuel cars can only be a short term stepping stone as there is not enough land to grow the plants to supply all the cars especially considering the water shortages in many parts of the world that climate change will cause. The surprising fact is that if the biomass used to produce the bio-fuel was burnt in a power station the electricity produced would power a battery electric car twice as many miles as a bio-fuel car (Well to Wheel efficiency). Check out this very eye opening short well to wheel efficiency presentation of the different car fuel types. http://www.teslamotors.com/display_data/tedpresentation_final.swf

Tesla motors (www.teslamotors.com) battery electric powered roadster goes on sale in the US in August approximately for around £45K. It has a range of 250 miles per 4 hour home charge with a 0 to 60 time of 4 seconds. The key point is that if a Roadster owner where to install only 3 kilowatt of solar photovoltaic panels on their home (in the UK) the panels would produce enough carbon free electricity to power the car 19000 miles per year!

www.nanosolar.com and others are working on thin film printable solar panels with a price of $1 per Watt! There is a quiet revolution going on in personal transportation and power generation been led not by the multinationals but Silicon valley start-ups . Within 10 to 15 years the internal combustion engine as used for personal transport will be as dead as the fossil fuel it burns.