/ Motoring, Sustainability

Does air pollution from cars affect you?

car pollution

Since London was issued with its first ‘very high’ air pollution alert at the start of the year, much has been written about the impact poor air quality has on our health. But does it affect yours?

Brixton Road in Lambeth, south London, became famous earlier this year when it breached its annual NO2 (nitrogen dioxide) allowance – just five days into 2017.

Later that month, on 23 January, London Mayor Sadiq Khan issued the first ‘Very high’ air-quality warning for the city.

This advises everyone within the capital to reduce physical exertion – particularly if they’re outside and by busy roads.

Cue a whole lot of media attention around the poor quality of the air we breathe.

Much of this has focused on NO2 (one of the NOx gasses), which is produced in large quantities by diesel cars.

And, while some car manufacturers are making progress on reducing the amount of toxic emissions from their models, many have a long way to go.

In our recent tests, we found that, despite universal limits, there are huge differences in the amount of NOx emissions produced by diesel cars from different brands, with Renault and Jeep among the biggest air polluters of the car makers we tested.

How bad is NO2?

So, what impact does NO2 have on your health? Well, there have been a number of scary reports concerning just that.

One study published in 2015 by the Environment Research Group at King’s College London, estimated that Londoners lost up to 88,113 life years to NO2 during 2010.

And it isn’t just London where poor air quality is a problem.

The Royal College of Physicians thinks around 40,000 deaths in the UK per year can be attributed to air pollution.

While a report from the European Environment Agency named poor air quality as the largest environmental health risk in Europe.

It’s widely accepted that NO2 inflames the airways and can lower immunity against lung infections.

Its effects are more pronounced on those who are vulnerable, such as the elderly and those who have an existing lung condition.

The affects

As a result to worsening air quality, major cities around the world are now committing themselves to banning diesel cars by 2025.

But do you notice poor air quality?

As someone with mild asthma, who lives by the sea but works in London, I notice a palpable difference in air quality between where I live and where I work.

That said, it isn’t the air quality that stops me from going out for a run on London’s streets during my lunch hour (it’s usually utter laziness).

But some people really suffer. The British Lung Foundation put me in contact with Janet Morrison, 62, whose existing lung conditions are worsened by traffic pollution.

‘I grew up in London but in 1966, at the age of 11, I moved to Southend-on-Sea in Essex. I had asthma as a child, but was diagnosed with emphysema and then bronchiectasis in my 30s and 40s – I’m now 62.

‘There’s a lot of traffic in Southend. It’s busy during the rush hours, but much worse at the weekend with all the tourist traffic, especially in the summer.

‘When the pollution gets bad, it feels like someone is sitting on my chest. I hate going out when pollution is high, but I can’t let it stop me.

‘I try to manage it with my inhaler, but if I’m driving somewhere in traffic, I have to close the vents in my car to stop the air coming in.’

What about you? Do you notice days when the pollution is bad? Do you have to take any precautions? Or has it never bothered you?


From spring into mid autumn, I often commute into central London by bicycle and you definitely notice when air quality is poor. I haven’t managed to get back on the bike yet, but I’m half tempted to get one of those face masks when I do.

Phil says:
1 May 2017

A face mask won’t filter out the very small particles or any of the NOX gasses which do the real harm.

I am not sure how much worse London is than other major towns and cities. Even in Norwich city centre, which is on high ground twenty miles from the coast and gets a fair blast of fresh air everyday, we notice the pollution levels in the main streets – many of which have recently been given over entirely to buses, taxis and distribution vehicles most of which leave their engines running while idle. I suspect most other commercial centres are similar.

Given London’s pollution levels I am surprised that Mayor Khan wants to expand the capital in all directions and increase the population. I feel a programme of dispersal would be better for Londoner’s health and well-being. This would require a complete prohibition of all new office buildings and commercial premises and strict controls on the reconstruction of existing sites.

The diesel car, with its NOx and particulate filth, is an unnecessary, anti-social and objectionable vehicle that should be condemned to an early demise.

I wonder how we replace all those commercial vehicles, let alone cars – diesel engines are ubiquitous in lorries, trains, buses, vans, plant, ships……….
Banning universally is unnecessary, but controlling petrol and diesel vehicles in town and cities can be done. You have to replace their role with other cleaner transport . how can that be done quickly? I don’t think it can so it will be a gradual process.

Which? says “data from our new test programme shows that petrol cars can produce more PM than diesels, and PM is a big part of the air pollution problem.”. Looks like we’ll need to ban petrol vehicles as well.

I’ve chosen to live in the sticks and hope that benefits my health. I would like to see those in towns and cities helped, but we need to think of practical solutions.

I agree that it will be extremely difficult and a long term project to replace diesel engines in commercial vehicles. They will progressively become more efficient and less polluting but they will be with us for many years. There is no effective substitute for deliveries. All the more reason to deal with the problems caused by cars which can be substituted by electric and hybrid alternatives, can be banned from town and city centres, and for which public transport can be a practical alternative in many instances. Yes, over time petrol-engined cars will also have to be subject to stricter controls as well as diesel-engined ones, but I think the pollution-reducing priority is with diesels so we need to start with those.

Hybrid buses are in operation and can become still cleaner. I am extremely disappointed that the government is not so committed to electrification of the railways now and sees ‘bi-mode’ trains as the answer – they are basically electric trains fitted with supplementary diesel engines to take over where the electrification stops so the electric trains will have to drag around the extra weight of a noisy and dirty diesel engine plus its fuel tank. This is a monumental Department for Transport fiasco that has received little media attention but will cost many millions of pounds to implement as well as additional running costs throughout the life of the trains.

At least the Underground and Overground and most of the suburban National Rail routes are all-electric in London. The Great Western suburban routes are being electrified leaving just the Chiltern lines and Essex Thameside [C2C] route as diesel powered into the capital. To think that London once had extensive electric tramways and trolleybus networks but now has some of the worst pollution in the country.

The LTC’s cab needs a minimum zero emission range of 30 miles per day to meet TfL’s requirements. London taxis do 150 to 200 miles per day, LTC say. So the extra miles depend upon a petrol engine/generator which although it powers the electric drive will be polluting. The same company is launching a van, with a battery range of around 66 miles then a further 340 miles using A 4-cylinder petrol driven generator.

Until we get much higher capacity batteries that will last the working day these seem to be just a step in the right direction. Why do we need so many cabs when we have a good non-polluting underground system? Rather than do a whole trip by cab. perhaps cabs at stations for the final mile or so might be healthier, with maybe more chance of staying on battery power.

It may have had electric transport, but it had filthy air from all the solid-fuel domestic fires. Before that it was polluted by horse excrement, urine, and their exhaust gases.

No one seems to have the courage or common sense to face up to the real problem – too many vehicles at a time. Just tinkering with individual vehicle emissions will help, but not cure. We need vehicles with sustained electric capacity for town use, switching to a conventional decent size engine for out of town – like a better BMW i3.

You can tell by the way Which write their articles you have no car lovers on your staff. I’ve seen you describe the Focus RS as the boy racers version of the Focus (a stupid, uninformed description), and go on about its high pm emissions at motorway speeds. Erm, what a surprise, it’s a 350hp monster!!! Who would buy one worried about emissions?! Anyway, i drive a 3.0 litre Jag and enjoy booting it everywhere i go, no doubt flying past anyone on the road who works for Which!! Oh…And any car lovers knows a good car is much more than just emissions, to omit a car from being a good buy just because in your opinion it’s emissions are too high is ridiculous.

But car buyers are terribly concerned about emissions, Dan. That is the reason they mostly give for having bought a Volkswagen and why they are so aggrieved about the corrupted test results.

I suspect many of those who post about VW emissions are more concerned about getting compensation. Otherwise, why did they buy a diesel in the first place? But then, I’m a bit cynical.

You only had to look at the rear of buses & lorries to wonder why on earth you would want a diesel car.

24 March 2017

How long ago was it when we were encouraged to buy diesel cars, rather than petrol cars?

I remember reading a few years ago, that a cow puts out as much methane in a day as a 4×4 in London, we can’t do anything about them, can we?

The cow’s methane output is part of the natural and historical baseload, and, as you say Chris, there is not much we can do about that if we want milk, meat and leather products. Luckily most of this gas is expelled in the countryside where it quickly dissipates. The internal combustion engine is capable of being modified and controlled and, as Which?’s statistics show, some cars are much less polluting than others, so the bad ones can be identified and progressively eliminated and the economics can be managed to incentivise electric propulsion, or reduced mileage. or exclusion from sensitive areas.

I was born in 1941 and remember the smog air pollution from coal fires and early combustion engines, which was far worse than the pollution that we have today as I used to ride a bicycle through traffic and at the end of my journey my face was like some one in the black and white minstrel shows. The clean air act was supposed to take care of that but does it? Heavy vehicles produce the worse pollution plus slow moving cars and vans which due to traffic calming are made to do so by local authorities. The other thing which people do not seem to appreciate is air pollution from aircraft which saturate our skies with thousands of gallons each time they take off. A jet engined air liner uses more fuel than a car uses in a year just to take one trip and records show that at any one time in a day or night there are 6000 aircraft in the sky, where does all that fuel go, it does not stay in the sky, but descends down to earth not just on our cities but into our country side and oceans. No one seems to mind this happening. The other causes of heavy pollution is the combustion of coal fired power stations and the manufacture of fuel whether petrol or diesel in refining plants but that does not seem to figure in government control. It is true that people are suffering and dying due to our misuse of our planets resources but this has always been the case. So what is the answer go back to horse and carts on land and sail across our oceans by ship or try to be sensible about our poor technology.

Lucy says:
24 March 2017

I don’t understand why more isn’t being done about engine idling. Men especially seem quite incapable of sitting in a stationary car without the engine running. Tradesmen will sit and have their lunch engine running,
windows open (so it is not just about keeping warm) breathing in the lovely fumes they are pumping out and polluting the whole street. Parents picking up children from school still sit there waiting with the engine running. There seems to be no understanding amongst the general population about how selfish engine idling is. We need to educate people much more and perhaps give traffic wardens powers to fine people. Notices in supermarket car parks would also help. Head teachers in schools should tell the parents not to engine idle.
And modern cars do need warming up guys! Switch the engine on when you are ready to move off not as soon as you get in the car.

We can, quite rightly, criticise the EC for their poor emissions testing using the NEDC (New European driving Cycle – except its very old). However they are currently trialling a Real Driving Emissions test (RDE) that measures emissions under a wide range of driving conditions on the road. This will lead to emissions regulations under more realistic conditions, as well as under laboratory conditions. The NEDC test is also being replaced by the WLTP that again is much more representative of real life driving.

I hope Which?’s tests reflect these EC test regimes otherwise results may not be comparable.

I don’t understand why more isn’t being done about engine idling. Men especially seem quite incapable of sitting in a stationary car without the engine running. Tradesmen will sit and have their lunch engine running,
windows open (so it is not just about keeping warm) breathing in the lovely fumes they are pumping out and polluting the whole street. Parents picking up children from school still sit there waiting with the engine running. There seems to be no understanding amongst the general population about how selfish engine idling is. We need to educate people much more and perhaps give traffic wardens powers to fine people. Notices in supermarket car parks would also help. Head teachers in schools should tell the parents not to engine idle.
And modern cars do need warming up guys! Switch the engine on when you are ready to move off not as soon as you get in the car.

1. We are so addicted to our cars, I have long thought that we will never abandon them until either we run out of fossil fuels or we choke. People are choking already, and the number of children with asthma has, I read, quadrupled in ten years. Very, very sad. One day we will marvel at the fact that, to get our bodies comfortably from A to B, we take one or two tons of metal, plastic and rubber with us every time.
(Fifty years ago I was a bus conductor – our buses were usually full – now we cannot even afford two crew to keep the harassed driver’s attention where it should be – driving, without continual distractions. Progress!).

2. Here in Ulster we are perhaps very lucky to have thousands of miles of fresh sea air blasting in from the Atlantic on the prevailing westerlies. Not smug, but grateful.

3. In 1958 we emasculated the railways. Every penny spent on roads was called ‘investment’ – every penny on rail was called ‘subsidy’. Subtle brainwashing.

4. The world enjoys castigating VW for the emission scandal – no doubt hoping for ‘compensation’ when the shouting is loud enough to turn into an irresistible mob. Why compensation? Drivers have lost nothing, the poor diddums.
My 2l diesel Passat was politely and efficiently ‘normalised’ free by VW with an electronic tweak. I guarantee that even before that tweak, it was one of the cleanest diesels available. Your research now shows that to be a fact. So why pillory VW continually? Do you not notice how quiet other manufacturers were, and are, about the ‘VW’ emissions? I bet they all have their fingers crossed behind their backs, hoping that the pressure remain on VW, and the spotlight not turn inexorably towards themselves. Surely Renault should take pride of place now in the emissions scandal – for much more genuinely harmful reasons.
(OK, I’m biased – have had five VWs, of which three Passats. Only had to sell two of the Passats when I emigrated each time … broke my heart when the first GL5 – petrol -went after 18 years companionship. Lovely engine …

Ian says:
25 March 2017

We are pensioners and bought a 2005 Jeep Grand Cherokee 3.0CRD in 2012. IT had a full service history which has been maintained ever since. The Jeep is used safely to tow our caravan weighing 2000kg as it has a kerbweight higher than the weight of the caravan. We live in a rural area so on some occasions a beefy vehicle is required. At the time of purchasing diesels were supposed to be okay. We cannot afford at this time to replace the vehicle and we doubt of any petrol engine vehicles are capable of safely towing the caravan. So where does this leave us as the Jeep is obviously fully paid up and who is going to give a pensioner credit to buy a later model vehicle?

re Article in Which? April by Adrian Porter (p23: “Car emissions: not all diesels are created equal”)

If I may digress a little since there is an important issue in all of this which seems to have been – as far as I can find – completely missed. Pose the pollution question this way: Do we want to save the world, or save the city!

Very simply put diesel power is the most efficient overall (cradle to grave) power source available so it could be argued that if all transport was diesel it would greatly help in the fight against global warming. However, local pollution caused by diesel emissions would be worse.

So, save the city or save the planet… difficult choice. Could the answer be “both”? Find an efficient way of producing hydrogen – that would do it. Possibly, but we are not there yet…

We can start to “save the city” by restricting the amount of traffic allowed to enter, particularly at peak times. Certainly not charging them to pollute – why does extra money help us breathe? We need to tackle the means of transporting people efficiently into and around towns and cities without everyone using their own personal polluter.

I find it hard to accept that diesel propulsion is the most efficient power source, especially in towns and cities where the engine is idling for lengthy periods and even when the vehicle is moving the engine is not operating at its optimum rate for power generation and a cleaner exhaust. Diesel engines are also noisy which makes life unpleasant for people close to roads.

You’re right in one respect i.e. most car engines, diesel or petrol, are optimised for higher speeds (usually around 56mph) than typical city values especially the most recent trend to 20 mph. That means more pollution – once again a difficult compromise kill by speed or by more pollution? Cynical or what?

In terms of converting fossil fuel into work the diesel engine is around 45% efficient compared with petrol 30%. Stop-start minimises idling. So it is one of the most efficient for independent transport. The problem is the conditions of use – not its inherent efficiency. So any power plant that runs but is not producing work is of course used inefficiently and will produce excess pollution. That is the problem we need to tackle. Control access to areas where population is concentrated and traffic volume currently is too high.

Small gas turbines have efficiencies of 25-35% but are unsuitable for direct drive, so for vehicles could generate electricity for battery storage in a hybrid vehicle. The upper limit currently for large gas turbines seems to be around 65% so possible scope for an improvement for vehicle power plants.

Thanks Malcolm. The efficiency per se is not the chief factor but the overall environmental impact. Hauling batteries around is not exactly efficient, but assuming the environmental impact of producing a set of batteries is on a par with the manufacture of an internal combustion engine the running function has negligible pollution discharge and is certainly much quieter. I believe direct charging from mains electricity supplies has the potential to be the most efficient and least harmful overall as a variety of input sources are available including renewables, transmission losses can become a negative factor however.

For personal transport in towns and cities, legs, bicycles, electrically assisted bicycles and scooters (“small power two wheelers”) can all be viable alternatives to cars.

How about one of these?

Credit: c5owners.com

I think rickshaws might gain traction too, Derek.

It’s quite difficult to get good/reliable information on what’s called “Life Cycle Analysis” (AKA cradle-to-grave) which compares various energy sources and includes the environmental costs (emissions) of the raw material, operation, decommissioning etc. Siemens have produced a document on wind power which does have most aspects of the environmental costs of energy production by wind power and shows that it is hugely better for example than conventional power stations (almost too good to be true!). One pertinent publication (2016) by the US Department of Energy reports that the “overall” green house gas emissions (GHG) based on present technology for internal combustion engines is 460 gCO2/mile for petrol (gasoline) and 390 gCO2/mile for diesel (about 15% less than petrol))…..it’s a long document (182pp) and requires some fortitude to read it all! However, whichever emissions problem is being analysed, the one conclusion is that we need significant reductions.

We are where we are. Almost everyone in this country has a car and almost every car is powered either by petrol or diesel. Road transport is almost entirely diesel driven. The country currently accepts that almost everyone can use the road and almost everyone uses the car to do anything outside his/her immediate environment. That’s the status quo. Changing that means providing alternative power for vehicles or changing our entire way of life so that personal transport is replaced by something else. I don’t see that happening, because we see our own transport as an essential part of being who we are and enabling us to do what we wish, when we wish. Curbing personal transport in towns and cities might be done by making this prohibitive in cost, though I wonder how long it will be before the motorist stops sitting quietly by, doing nothing. The outcome of city bans is that all vehicles travel the arteries and park somewhere outside. That’s not conducive for theatre visits, heavy shopping, visiting a city restaurant or living inside the no car zone. So, this is possible, but has side effects, which might reduce city life as well as its pollution. The changing of our car dependency is not something that will happen. It is too embedded in who we are. Battery technology is improving year on year, but we are far from producing anything that replaces what we drive now both in terms of infrastructure and practical use. Even the latest vehicles require a ninety minute stop every hundred or so miles at a place where charging is available. A queue at one of these points is likely to be hours long. Imagine the car parking necessary to charge every car with a flat battery. The fear of pollution drives the search for alternatives and the lack of these makes for solutions that cripple our freedom and probably won’t solve the problem. This particular branch of science is moving forward too slowly for our needs and no one is prepared to commit entirely to any of its branches, though electric in one form or another seems to be winning at the moment. When the internal combustion engine was invented the drive was to make it bigger and better; that was progress. Now progress is to reduce pollution and that’s counter intuitive to the past. Squaring that circle is at least twenty years away.

Ah, gasoline – the modern day opium of the masses?

I drive diesel and have done so for many years, for several reasons: longevity, reliability, high mpg, cheaper to service (fewer moving parts). I’ve never bought new, why would I with the huge depreciation that happens the minute you’ve bought it? My current car is a five-year-old Volvo and I’ve no plans to change it for at least another five years when I’d expect to spend around £8,000 for another car. I’d like my next car to be a hybrid and a suitable equivalent replacement, new, would cost at least £20,000 so, if I’m to be priced off the road and offered, say, £2,000 towards a new car, where am I expected to find the other £10,000? I’ve read that fuel manufacturers could make diesel fuel ‘cleaner’ but it would be more expensive. Isn’t this the way forward? It would help all diesel vehicles, including buses, lorries, taxis, etc, and if necessary the government could do its bit in the short term by reducing the high level of taxation on fuel. As hybrid and electric technology improves people will naturally go down that route and diesel cars will eventually disappear and vehicles that have to use diesel (assuming there hasn’t been a breakthrough in the meantime) will be using ‘clean’ fuel. Yes, it’ll take time but as VynorHill says, we are where we are and that’s where we have to start from

Vauxhall have been caught cheating with their diesels now.
This is getting ridiculous.
It is starting to look like everyone is cheating,

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There was a report in the Mirror / Panorama in Nov 2015 alleging a Zafira was tested and emitted 2.5 times the NOx limt – a claim refuted by Vauxhall. However, is there more?

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Surely one answer to the problem in cities would be to replace the diesel buses with trolley buses. Obviously they would need overhead wires installed, but far simpler (& cheaper) than changing to trams. No requirement to dig up the roads & no subsequent danger to cyclists, from getting their wheels stuck in the rails. No pollution from the vehicles & maybe none elsewhere either if solar or wind is used to supply the electricity. No noise pollution either as buses use rubber tyres on tarmac, not steel wheels on steel rails.
I had the misfortune to drive through Edinburgh city centre some years ago, when they were installing their tram system. It caused massive disruption & resulted in absolute chaos. The system had to be curtailed in the end because it ran hugely over budget & took many years over the estimated time to install. How much simpler & cheaper it would have been if they had chosen a trolley bus system instead of a tram system.
More recently the tram system in Birmingham has been extended to New Street station from Snow Hill. Again, major roads dug up for years & huge expenditure to save a five minute walk. Trolley buses would have been much quicker & simpler to install but it seems the present fixation is for trams or hybrid buses. Why? What is wrong with trolley buses that they are so out of favour? They must be safer than trams as well because the driver can steer around any obstacle, try doing that with a tram!

I agree with you, Emmbeedee. There is no doubt that journey times can be shorter with trams because they generally have indisputable priority on the streets whereas trolleybuses get caught up in traffic, but there are ways round that nowadays with advanced signalling systems and sophisticated traffic management. Trams seem more popular than buses and where they have been introduced ridership has exceeded forecasts, but trolleybuses have nearly all the same advantages as trams without the need for boarding platforms, rails and complex highway engineering. Both systems require overhead wires and a trolley system seems to have less clutter than a tram system.

The only significant advantage of trams is that by forming two or three units together one tram can carry a lot more passengers than a single trolleybus so one driver is required compared with three for a trolleybus service carrying the same number. But in the UK, outside of Blackpool, there are no tram systems using double-deck tramcars whereas most trolleybuses were double-deck vehicles and could be in the future.

The ease of extending or changing the route of a trolleybus system should count heavily in its favour. In terms of street furniture, when many cities had trolleybus networks, the stanchions that supported the overhead wiring also carried the public lighting so there need be no increase in the number of columns if planned carefully.

I must admit I cannot see why trolleybuses have not been reintroduced in the UK. As a lighter vehicle a trolleybus requires less power and the capital cost of a complete system must be much lower so the payback is quicker. The growth rate of the renewable energy sector would allow a faster roll-out of trolleybus systems than the development of an equivalent-capacity tram system.

It is a shame that the government threw out the proposed trolleybus system for Leeds a year ago, but that decision was based on a planning inspector’s report following a thorough public inquiry which made clear that the choice of route, the proposed infrastructure, reputed environmental drawbacks, public opposition, and the lack of demonstration that trolleybuses were superior to hybrid buses all counted against the scheme. I think there is also an official mindset at the Department for Transport opposed to both tram and trolleybus systems because, apart from a few route extensions, there has been a lack of development in the UK with very few of our major cities or conurbations having a modern metro system.

In Charlotte, NC, USA, hybrid electric buses link the downtown area with the a major retail park and the city’s international airport.

I think we could follow their lead and use that technology too – no wires or rails would need to be installed.

And, of course, we should place more restrictions on the use of smoky diesel and stinky petrol cars in city centres.

There are 2,307 hybrid buses, 71 electric buses, and eight hydrogen buses currently operating in London, out of a total bus fleet of 9,588. They are also used in some other cities. It is probably the best way forward at the moment. It is certainly the most flexible form of urban transport as diversions and service augmentation are easy to implement.

One rather interesting development is the use of ultracapacitors in electric buses. The system does away with the need for overhead lines, and just needs overhead power points at alternate stops. China’s currently experimenting with the idea.


Thinking about it trams always seemed magical to me as a child. Last year we went to Manchester for a few days and used the Metro. It had the same appeal for me and I remember it with considerable fondness.

I agree with Emmbeedee and think that trolleybuses are more practical than trams. It was very interesting to visit the Trolleybus Museum at Sandtoft last year.

When we had a long weekend in Manchester we liked the trams. We took a long ride out to Eccles and came back on the train which was a rattletrap in comparison [although the journey time was much less].

Nice one Ian,

…and when they upgrade to flux capacitors they’ll be able to keep even better time 🙂

Trolleybuses still require an extensive overhead wire system with effectively “points”, and limit the routes that buses can use. With developments in batteries, and more available space than in cars, I’d suggest that battery-powered buses within towns and cities make the most sense. Charging points can be devoted to them at termini or, as suggested above, en route with capacitors, or they can be hybrid to use fossil fuel in appropriate areas with more sophisticated pollution control than would be built into smaller vehicles.

I likes trams but agree on the disruption, and huge cost and complexity of trackwork. Unless they run on segregated track they cause huge disruption, particularly these days with heavy traffic. They had priority because all other traffic had to stop when they did.

The upheaval of laying tramlines is immense. Most of the problems with the Edinburgh system [massively truncated because of spiralling costs] was that the city engineers did not have reliable data on all the underground services. It’s not just a question of cutting two slots in the road and putting rails in. The whole road has to opened and excavated to put a solid foundation in and all services that are underneath have to be diverted [electricity, gas, water, telecoms, drainage, and sewerage mains plus communication pipes and cables from the mains to every property along the route].

A large extent of the Croydon tramway was laid on former railway lines, roadside verges, or reserved track but the town centre works caused enormous disruption; when riots took place in Croydon a few years ago part of the tram route was badly affected by fires and had to be shut down for some time before services could be restored. At least buses can be diverted easily and a major incident wouldn’t isolate the depot as happened in Croydon.

Other than funded extensions to existing systems I doubt we will see any significant investment in tramways in the UK now so it would be better to develop cleaner buses [and private coaches – lots of them penetrate city centres and stand around with their engines idling; they are often not so well maintained as public service vehicles].


Something from September 2015 on hydrogen fueled buses giving the state of play at that point. High reliability, quick refueling, ultra-clean, and good range seems to fit the bill as a good mass-mover with the flexibility to adapt to new routes.

The use of electric power-assisted bicycles with designated roads could easily reduce pressure on public transport and reduce emissions. At a cost of say £1000 many commuters could become free of rail and bus BUT the sticky point is road safety for cyclists. In France purchasers get a 200euro rebate as part of the Govt plans to reduce pollution and lessen congestion. Car sharing is highly developed as is the use of electric cars.

In this chicken ad egg world I would suggest bus and cycle only roads gridded through London/city x and making use of any alternate routes like old sidings and or running pontoons along perhaps rivers and canals. where it makes good sense. One might even halt river traffic for rush hours to cross rivers when it makes sense.

Unfortunately radical thinking – other than the remarkably stupid floral bridge – seems alien to those with the power to make it happen.

I enjoy walking on disused railways, canal towpaths and anywhere it is reasonably flat. I have no problem with most cyclists but some have turned some routes into racetracks and even publish their achievements on the Strava website. 🙁 Here is a well publicised example on the Kennet & Avon canal between Bradford-on-Avon and Bath: https://www.strava.com/segments/2233549?hl=en-GB

I fully support encouraging walking and cycling but cyclists need to be protected from users of motor vehicles and pedestrians need to be protected from motorists and cyclists.

Reports suggest that, having spent £40 miilion on this project – for nothing substantive – Sadiq Khan has withdrawn his support. Hopefully this vanity project will now be terminated. However a number of people will be pleased with what they have earned from it to date.

Cycling, particularly electrically-assisted, is a good way for many to travel even in our hilly wet country – suitable attire deals with the rain. However many are not able to cycle. Whilst personal transport is convenient, we’d likely still end up with battery-powered traffic jams. Good public transport is surely the real answer, providing it covers the town and city properly – even if allied with smaller vehicles for less-used routes. With the volume of commuters at peak times it would run into the same problem as other services – a huge demand for vehicles at peak times, with staff and vehicles lying idle for much of the rest of the day. So we must also look at staggering working hours to help even out this demand and use resources and staff as efficiently as possible.

I wonder if Khan was influenced by the High Line?


Not sure I’d describe it as the “remarkably stupid floral bridge”, however, Patrick; essentially, from what I can see, he’s merely creating another park area. It does seem pricey, I grant you, but the cost of land in London might suggest this is actually a cost-effective proposal. I quite like the idea, I have to say.

Thanks for the link.

In Germany they make a distinction between the simple e-bike and the S-bike and similar which go above 25kph up to around 45kph. The fast ones are classed as mopeds and have to be taxed and insured. I would suggest that these not be allowed on towpaths etc.

Random checks and confiscation of any S-bikes would work wonders.

However it does illustrate that there needs to be some regulation but overall less pollution and healthier citizens which surely is a very big win.

Reducing pollution is one issue and I think e-bikes do very well in this respect and overall will make for healthier people.

Reducing congestion I suggest also occurs because of the high density on the road that can be achieved – witness Holland or China pre-motor car.

However on the “many cannot cycle” I was wondering if you could put figures to that. I have several very elderly folk who ride past my house daily and I suspect that doing so has enabled them to keep fitter for longer – but that is of course surmise on my part.

This Wikipedia article is illuminating and even mentions bike congestion !

No powered vehicles are allowed on canal towpaths, with the exception of mobility aids: https://canalrivertrust.org.uk/about-us/our-campaigns/share-the-space-our-towpath-code/top-tips-for-sharing-the-space/towpath-faqs That does not apply to those canals not managed by the Canal & River Trust. Rivers are more complicated because not all are under the control of the Environment Agency and many don’t have footpaths.

I’m involved with a charity that encourages responsible cycling in the countryside but there are some cyclists that are oblivious to others. I have already been taken to a fracture clinic thanks to a cyclist and had a few near misses thanks to pavement cyclists. I am no expert but footpaths used by cycling commuters seem to attract fast cyclists.

There is now a combined footpath and cycle path from where I live into town. I have not seen anyone racing yet. I intend to use it. More people would cycle if it was safe to do so.

Do you mean Khan or Boris? As you are not a rate-payer in London and would not be required to fund its upkeep I can admire your relaxed attitude. : )

In any event using an existing facility is rather different from building a new bridge. This pre-dates High Line and the French of course do it in style
“The Coulée verte René-Dumont or Promenade plantée (French for tree-lined walkway) or the Coulée verte (French for green course) is a 4.7 km (2.9 mi) elevated linear park built on top of obsolete railway infrastructure in the 12th arrondissement of Paris, France. It was inaugurated in 1993. ” …. [it had been started in 1986]

At least cycle and electric vehicle congestion does not create pollution in the same way that diesel and petrol vehicles do.

James de Raeve says:
5 May 2017

In the article on cleaner cars, I read “Hydrogen is the most abundant element on the planet, so it’s inexhaustible as a fuel”

I appreciate that Which? does a great job of translating technical stuff into concepts and language that are accessible irrespective of background, but this is a real howler that should have been caught before publication.

1. Hydrogen is the most abundant element in the universe and solar system, but on our planet the no 1 is iron. The no 1 in the earth’s crust is oxygen with hydrogen at no 10 (https://en.wikipedia.org/wiki/Abundance_of_elements_in_Earth%27s_crust). In the oceans, hydrogen is no 1 by number of atoms, and about 10% by weight. Free hydrogen gas in the atmosphere is less than 1 part per million.

2. Hydrogen is not an “inexhaustible fuel”. All the hydrogen in the oceans has in effect already been consumed as a fuel and turned into water. Photosynthesis has used water to make hydrogen to give us hydrocarbons, of which we use methane to make hydrogen gas. We can make hydrogen from water as well, but that takes more energy than starting with methane.

Hydrogen is not really a fuel: it’s a method of storing energy that beats batteries in terms of KWh per Kg and KWh per Litre (lighter and smaller for the same range) …. but the refuelling infrastructure costs rather more! I suspect both will have their place when fossil fuels are behind us.