31 Jan 2008
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WhatGreenCar? provides expert & independent information to those researching more environmentally friendly cars.
The core of the site content was first published by Dr Ben Lane as an ebook in 2004 and a second edition was produced in 2005. Dan Fallon joined Ben in 2006 and together they founded What Green Car? Limited. The company’s mission is to be acknowledged as the UK’s leading information guide to buying and owning a green car.
The WhatGreenCar? rating system expresses a vehicle’s lifecycle environmental impact as a score out of 100 ranging from 0 for the greenest vehicles to 100 for the most polluting.
The rating system used by WhatGreenCar? is based on an assessment of the environmental impacts associated with a car’s use and manufacture. This includes all aspects of producing and using the fuel — the fuel cycle (primary production, extraction, transportation, refining, and vehicle operation), as well as the vehicle’s manufacture, assembly and disposal — the vehicle cycle.
The WhatGreenCar? analysis first quantifies the extent of life cycle emissions arising from the fuel and vehicle cycles (known as an emissions inventory). The air emissions assessed include the EU regulated emissions — carbon monoxide (CO), oxides of nitrogen (NOx), hydrocarbons (HCs) and particulates (PM) — and sulphur dioxide (SO2). In addition, the three main greenhouse gases associated with road transport are assessed: carbon dioxide (CO2) , nitrous oxide (N2O) and methane (CH4).
Next, the WhatGreenCar? analysis conducts an emissions impact assessment — as its name suggests, this quantifies the impacts of the emissions rather than just quantifying the amount of emissions produced. The advantage of this approach is that the varying levels of all the emissions assessed can be combined to produce an overall environmental impact — without this approach it is difficult to know how to compare (for example) a car with high CO2 and low NOx, with a second vehicle that has low CO2 and high NOx.
The emissions impact assessment is achieved by the use of an environmental rating tool first developed by the European Cleaner Drive Programme to assess the impacts associated with the fuel cycle. This rating system uses recognised ‘external costs’ to establish the relative weight to attach to different emissions — the external costs are values expressed in monetary terms that reflect the overall damage to the environment and to human health. The analysis used by WhatGreenCar? extends the Cleaner Drive method to include vehicle cycle (car manufacture and assembly).
Using the WhatGreenCar? rating system, the level of environmental impacts are expressed as a score between 0–100 — the lower the score, the less the environmental impact (this reverses the Cleaner Drive scores which were higher for lower emission vehicles).
Input data for the WhatGreenCar? rating methodology comes from number of reference sources including: the Vehicle Certification Agency (for vehicle or tailpipe emissions), Concawe/JRC for fuel production greenhouse gas emissions, and numerous academic papers that estimate the emissions produced during the production of materials used for vehicle manufacture. A selection of the most important references is shown below. For a detailed report on the rating methodology adopted by WhatGreenCar?, see the report entitled Life Cycle Assessment of Vehicle Fuels and Technologies, which is available for download from the Ecolane website.
For more information on the analysis used, see the report entitled Life Cycle Assessment of Vehicle Fuels and Technologies
WhatGreenCar?, Unit 62, Spike Island,133 Cumberland Road, Bristol BS1 6UX, UK
Phone: 0117 929 8855
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