Anche secondo me è una lotta politica contro il diesel. Attualmente un euro6 diesel non si capisce perchè debba essere vietato rispetto a motori benzina omologati minori da euro5 in giù.
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10 Things You Need to Know about SMMT’s 10 “Facts” about Diesel | Greenpeace UK
10 Things You Need to Know about SMMT’s 10 “Facts” about Diesel
Posted by
Mel Evans - 19th April 2017
2. WHAT THEY SAID: Diesel is critical to reducing CO2 emissions, which in turn is tackling climate change – diesel cars emit, on average, 20% lower CO2 than petrol equivalents.
Really SMMT?
Actually on average diesel cars emit more CO2 than petrol cars – because diesels tend to bigger than petrols. Your own figures tell us that in 2013 the average diesel car emitted 129.2g/km of CO2. The average petrol emitted 128.8g/km.
5. WHAT THEY SAID: Advanced diesel technology has virtually eliminated emissions of particulate matter, with 99% of these soot particulates captured by special filters fitted to all new diesel cars since 2011.
WHEN ACTUALLY…
People regularly get garages to take their diesel particulate filters (DPFs) off to save fuel and to do so is not even illegal in the UK! In fact, one quick search online for DPF removal gives you
ads by garages advertising the fact that they remove filters.
The idea is that modern diesel cars filter most of this particulate matter (PM) out
but in practice these filters are often faulty or are removed to improve performance. Without a fully functioning filter system minor efficiency advantages of diesel are negated by the warming impact of black carbon. After the initial test there is no ongoing test to check on the car’s filter system. Given a new car would be expected to last for ten to fifteen years, that’s masses more PM emissions than SMMT claim.
Also, not even mentioning that new diesel cars regularly emit much more NOx than they should is a problematic oversight.
6. WHAT THEY SAID: The latest Euro 6 vehicles are the cleanest in history – and light years away from their older counterparts.
WHEN ACTUALLY…
As Which? describes their latest tests on Euro 6 vehicles: “We’ve found that of the diesel cars we’ve tested, nearly a quarter would exceed Euro 3 limits (passed in 2001) when faced with our more realistic tests. This means these cars don’t pass the earliest emission regulations from this century.”
9. WHAT THEY SAID: Contrary to recent reports, diesel cars are not the main source of urban NOx. In London, gas heating of homes and offices is the biggest contributor, responsible for 16%. While road transport as a whole is responsible for around half of London’s NOx, diesel cars produce just 11%.
WHEN ACTUALLY…
Air pollution is complex and its sources are varied. We know that
in cities like London, road transport is responsible for 50% of NOx emissions – much more than domestic and commercial gas. In London,
diesel cars – not including buses –
are responsible for 24% of NOx emissions on the roads. This data covers the Greater London Authority and is tracked by the
London Atmospheric Emissions Inventory.
And
across the whole of the UK, diesel vehicles are responsible for 90% of NOx emissions on the road.
Questions and Answers
What does Greenpeace think about Hybrids?
Hybrid cars reduce fuel consumption when in city traffic by switching to run on an electric motor. The car then switches to a petrol or diesel engine for longer distance trips e.g. outside cities. Smaller cars with hybrid engines can be extremely efficient,
but they do not provide significant reduction in fuel consumption when applied to bigger engines or heavy vehicles like premium cars or SUVs.
They also perform badly on long distance driving where there is less chance to gain energy from braking.
What does Greenpeace think about electric cars?
Fully electric cars run with a level of emissions related to their source of electricity.
To be truly sustainable electric cars need to be powered by clean and renewable energy sources such as solar and wind. Greenpeace does not consider nuclear power to be clean or sustainable.
What does Greenpeace think about bio-fuels?
Biofuels are very problematic.
In many cases they do not contribute to reductions in greenhouse gas emissions due to the emissions caused by their production, often related to land use and deforestation. The availability of real sustainable biofuels is limited and preference should be given to using them for power generation which is a more efficient use of these fuels.
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Fact Check: are diesel cars really more polluting than petrol cars?
Fact Check: are diesel cars really more polluting than petrol cars?
May 2, 2017 1.27pm BST
Diesel was promoted as a more environmentally friendly fuel as part of the
EU’s response to the 1997 Kyoto Protocol to reduce greenhouse gas emissions, especially carbon dioxide (CO₂). Diesel engines are “lean-burn”, meaning they use less fuel and more air to get the
same performance as a petrol engine.
So,
while diesel fuel contains slightly more carbon (2.68kg CO₂/litre) than petrol (2.31kg CO₂/litre), overall CO₂ emissions of a diesel car tend to be lower. In use, on average, this equates to around 200g CO₂/km for petrol and 120g CO₂/km for diesel.
But even when governments were promoting diesel cars,
we knew there were issues with toxic emissions (those immediately harmful to humans, not CO₂). Heating air in an engine produces nitrogen oxides (NOₓ) which include the toxic nitrogen dioxide (NO₂), greenhouse gas nitrous oxide (N₂O) and nitric oxide (NO), which reacts with oxygen to form NO₂. In a petrol car, these can be cleaned up by a three-way catalytic converter so that it emits on average around 30% less NOₓ than a diesel car, without after-treatment.
We know that
long-term exposure to nitric oxide can significantly increase the risk of respiratory problems, and so these emissions have been regulated for some time. The fine particulate matter (PM) that diesel engines produce
also causes cancer and can have acute respiratory effects.
Particulate filters in car exhausts can reduce PM emissions
by more than 90%, but they require good operating conditions and regular maintenance.
They can also produce more nitrogen dioxide, making diesel one of the main sources of this toxic gas.
The science now tells us that diesel vehicles cause more than four times the pollution than petrol cars.
Today’s EU petrol and diesel CO2 standards (Euro 6) are very similar. European Union, Author provided
For all the differences between petrol and diesel cars in the past,
current EU emissions standards for new vehicles of both types are quite similar. But there are still many older cars on the road that conform to earlier emissions standards.
Plus, in order to achieve these standards, diesel engine manufacturers have had to resort to technologies such as particulate filters, which tend to clog up when used mainly for urban driving. And the latest emissions technology requires the owner to regularly add a urea mixture such as AdBlue to the engine. By contrast, petrol emissions systems regulate themselves, needing less driver input.
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Car buyers guide: You, your car and the environment | ETA
Nitrogen oxides
NOx are the pollutants most strongly linked with acid rain, combining with water vapour to form a dilute but deadly nitric acid solution, causing serious damage and inhibiting the growth of plants. NOx are also contributing pollutants to photochemical smog, they irritate the lungs, and increase susceptibility to viral infections.
