|Electric railways already exist in London, as do trams / light rail in some selected areas; however only the Croydon Tramlink system sees the electric transports travelling within the street environment - which is where the most serious urban air pollution is to be found.
Poor Health Caused By Air Pollution Is A Big Problem In London; There Are More Than 7000 Diesel (And Diesel-Hybrid) Buses On London's Streets And There Is Hard Proof§ That These ARE Part Of The Problem
This page advocates zero-emission electrically powered trams and trolleybuses as representing a significant part of the solution.
In 2013 132 People Were Killed On London's Roads
Buses in the very badly polluted Putney High Street - as described in the text above and below.
The Putney High Street study found that overall cars made up two-thirds of the total vehicle flow
2016: Putney High Street Is Awarded A Dubious 'Honour'
In January 2016 Putney High Street became the first location in London to exceed its entire annual quota of N02 air pollution EU hourly limits. Under EU rules it is only permitted to breach these hourly pollution limits 18 times in an entire year. At 7am on 8th January the pollution monitoring facility on Putney High Street recorded its 19th breach of pollution limits.
However this is not the whole story, since the air pollution monitoring facility on what is probably London's worst street for air pollution (Oxford Street) was offline all week due to a malfunction. In 2015 it took just a couple of days for Oxford Street to breach its annual NO2 air pollution limit, and throughout the year it breached this limit more than 1000 times!
The hourly EU limit is 200 micrograms of nitrogen dioxide [NO2] per cubic metre. Nitrogen oxides [NOx - which includes NO2] is produced whenever combustion of hydrocarbons and oxygen occurs in the presence of nitrogen. It is a component of the waste gases emitted by diesel engines such as are used by lorries, buses and some cars. It affects lung capacity and growth.Full story:
|Zürich, Switzerland, where as part of environmental policies designed to protect the health of city-dwellers by minimizing urban air pollution motor buses are generally restricted to
outer suburban and rural services.
Trams (streetcars) are almost always electrically powered - indeed this feature is often touted as one of their major benefits - and there really is no reason why buses should not be equally city (and town!) friendly.
It really is most strange that so many transport 'experts' (operators, environmental advocates, lobby groups etc.,) have double-standards with respect to air quality (or lack of) and bus / tram propulsion systems.
Harmful Poor Health Conditions Caused By Air Pollution Include:
|For decades London's Oxford Street (which is restricted to just buses, taxis and local access) has been at the top of the list of British streets with the most severe motor-vehicle derived air pollution.||What a pleasant, fume free contrast to Oxford Street:
Modern trolleybus in Geneva, Switzerland sharing the
pedestrian zone with the trams.
For First Time A Study Looks At Nitrogen Dioxide
|The south-facing wall at Edgware Road (Bakerloo Line) underground station which in a trial to test ideas that might reduce airborne pollution was planted as a 'green wall'. This comprises a variety of living plants that absorb some harmful pollutants. Whilst this has been found to be of benefit, and to be visually attractive, it did not meet with universal acclaim, with some people saying that it looks rather 'twee' and critics labelling it as representing environmental tokenism.|
Actions to reduce total levels of the air pollution emitted by London's buses include a phased replacement of older buses with newer buses which have less polluting diesel engines that meet more stringent European pollution standards, the introduction of diesel hybrid buses which combine a diesel powered generator with a battery electric drive train, London taking part in multi-national experiments with Hydrogen Fuel Cell powered buses and trials with battery electric buses.
London's Mayor Exposes The Truth About "Euro 4 / Euro 5" Emissions Standards
In an effort to reduce the quantities of tailpipe pollution emitted by road traffic the European Union introduced a series of emissions standards which over time have become ever more stringent. These are known as Euro x with the letter x being replaced by a number that varies according the standard which is being adhered to. Many well meaning professional people have placed blind faith in these emission standards as representing a viable attempt to ameliorate the situation, however in April 2014 Mr Boris Johnson (who at that time was Mayor Of London) revealed that the Euro x scheme is actually a sham designed to hoodwink and placate as many unaware, uncritical, trusting people as possible. Writing in a newspaper column he said... "the motor manufacturers have been able to diddle the Commission: the cars and trucks have appeared to conform on the test tracks; but when it comes to everyday use, on real streets, it is a different story".
The problem is that the tests are conducted on new vehicles (which have brand new engines that are in tip top condition) on test cycles on a test track - and NOT on real-world road traffic situations as per our streets. These standards also take no account of the fact that emission performance deteriorates as the engine ages - even with perfect maintenance.
The full article can be read at this link:
For 2015 a new standard called Euro 6 was introduced. This standard mainly targets two types of emissions: nitrogen oxides (NOx) and particulate matter (PM), with the aim of reducing these by 80% (NOx) and 50% (PM).
But... with grid-powered electric trolleybuses these pollutants would be reduced by 100%, or in other words, totally eradicated. You cannot get cleaner than that!
There are no such things as clean diesel vehicles. Just "less dirty"
|A battery electric bus on trial in London. These buses work on short city-centre routes so even if used intensively they are unlikely to travel as much as 100 miles (160km) in the one day. This is significantly less than many buses travel on other heavier duty services.||Some people see solutions in diesel-hybrid buses which couple diesel engines with an electric drive system that is powered by batteries.
But the batteries only have expected life-spans of 7-10 years
and then need replacing - at great financial cost!
Battery Technology Not Mature Enough!
Battery electric trams are even more rare than most endangered species... it is always expected that trams will be powered by direct connection to the national grid.
Although the numbers of pure battery electric buses is growing they remain a niche mode of transport. The reason why they have not found favour for mainstream high capacity services is that real-world commercial experience has found battery technology to not offer a viable solution. In short, batteries cannot hold enough stored energy to power a large high capacity bus for a full day's work. Batteries are very heavy so getting around this restriction is not as easy as adding a few more batteries - at least not if the desire is to have a bus which can carry enough passengers, stay within legally mandated weight limits and also be commercially viable.
Whilst there is one Chinese bus manufacturer who claims otherwise, their vehicles only store enough energy for light service bus routes which travel up to 250km (155miles) a day - rather than the 350km (217miles) (or more) which some bus operators need. This is achieved by packing three tonnes worth of batteries into the bus - and as a result to avoid breaching the legal weight for two-axle buses they are only allowed to carry 69 passengers. By way of contrast the (same sized) diesel buses which are used on the same London bus routes are allowed to carry 96 passengers.
To get around battery capacity limitations buses designed for stop-start urban routes often have battery-electric drive systems and a small diesel engine that is attached to a generator which can top-up the batteries as required. To minimise emissions the diesel engine will always run at its optimal speed / power setting and there will be times when the bus is operating in solely battery mode. These are called hybrid buses. Because these use diesel engines they still emit harmful air pollution in the streets through which they travel.
An idea designed to further reduce emissions within the urban area by extending the range the bus can travel in solely electric mode is daytime topping-up of the batteries during the layovers between journeys at the bus terminus. Called opportunity charging there are several variants of this system which include receiving power via direct contact from above the bus and induction power transfer from a special charging point that is flush with the road surface. The term opportunity charging can be defined as charging the batteries whenever the opportunity arises and in trials overseas has also included quick partial recharging at bus stops whilst en route. Of course such recharging is only possible at locations where the required infrastructure has been installed, and is available for use.
In 2015 London started trialing opportunity charging (via road surface induction) some specially modified double-deck hybrid buses on the 9 miles (14 km) route No.69, the expectation being that - at first, when the batteries can still hold their maximum charge - these experimental buses will be able to travel for up to 80% of the time in battery electric mode, and for the remainder of the time they will rely on the onboard diesel generator to provide the required electrical power. They will also use their diesel engines if they miss a charging session, perhaps because the bus was running late and there was insufficient time for battery charging or because another of the experimental buses is already using the charging station. The three buses used in this trial have been nicknamed as extended range hybrids and virtual electrics.
|One of the experimental induction charged extended range hybrid virtual electric buses calls at Stratford bus station.||A road surface induction charging plate, as seen in Turin, Italy where induction charging as been underway for a number of years.|
London is not the first British city to trial induction charging - since January 2014 a midibus route in Milton Keynes has been using a fleet of eight pure electric buses which use induction to recharge their batteries. Before the battery buses took over this route it needed just 7 buses, but the approximately 10-15 minutes of extra time needed for charging the batteries when between journeys at the route termini means that more are needed. The fleet actually includes nine buses, one of which is diesel powered. This was added when it was realised that at busy times eight buses would not suffice.
Another issue with batteries is that they only tend to last 5-7 years before their reduced ability to hold an electric charge makes them unsuited to power buses. Replacing batteries can be extremely expensive - when Rome, Italy faced this issue they found that the €30,000 cost per bus represented a serious financial headache. When New York, USA, faced this scenario they stopped buying hybrid buses and went back to diesels - the cost was just too much! Depending on battery type the safe disposal of life-expired batteries also poses environmental issues.
There are actually several different types of hybrid propulsion systems, the version described here is the type that is most suited for urban buses on stop-start services. More information about these can be found on the citytransport.info website - there is a link in the links section at the bottom of this page.
Electrifying Bus Services Represents The Easiest Quick Win Solution
Of course buses are not the only sources of air pollution, even the Putney High Street air pollution report detailed near the start of this page also talked about the other road traffic - and it stand to reason that these need to be cleaned-up as well.
Sending more freight by train (or even coastal waterway / inland canal) for final delivery by local area electric commercial vehicles would help to reduce both urban air pollution and traffic congestion - but even once the decision to do this has been made it will still take time for the cleaner alternative vehicles which meet the transport needs of the many commercial organisations and private people who use our roads to be designed, manufactured, tested and available to purchase. Another hurdle to overcome is that since the railway strike in the early 1950's which crippled British Industry (because no goods were moving) it has been Civil Service and Government policy for us here in the UK to have a road-based decentralised transport system operated by as many privately owned transport companies as possible.
More tram services are very much part of the solution, however in the UK the process of achieving planning permission and installing the physical infrastructure takes decades - during which time people are constantly being assailed by the polluted air. Even cities such as Manchester which has the most extensive network of modern trams in the UK still has many bus services for which conversion to tramway will never be financially viable. Because trams run on steel rails they are usually seen as a rail-based transport mode, even though they can also travel on the public highway with other traffic.
The only part of the road-based transport industry where all the required technology is available right now is the urban bus industry.
As said above, the road freight industry is not yet ready to switch away from diesel fuelled vehicles. Neither is private motoring - although it probably will be quite soon.
By way of contrast, electric buses are available to purchase 'today'. Another advantage which most urban bus services have is that they travel over pre-defined fixed routes, so electrical supply fixed infrastructure would only need installing on a small percentage of the entire urban road network.
This makes converting buses to electric traction the easiest way to achieve a first stage quick win in reducing urban air pollution.
Because of bus deregulation most local governments outside of London no longer have full control over bus services in their areas and therefore there would need to be enabling legislation which allows for the installation of power supply infrastructure which can be used by more than one local area bus operator and which allows the local government to stipulate that urban bus services must use that wiring.
London is different, as here deregulation operates differently and instead the various bus companies must compete for the right to operate bus routes over which the Mayor still retains absolute control. Therefore if (s)he and his (her) transport office (Tf L - Transport For London) really thought that air pollution was a serious issue they could take the necessary action to eliminate the urban air pollution from the motor vehicles over which they have direct control. IE: "the buses"! This would be by converting them to grid-powered 100% electric traction - either as trolleybuses or trams - or for low capacity quieter routes, battery electric buses.
Permanent Connection To The National Grid Is A Proven Viable Solution!
What is being advocated here involves the use of technology that is commercially tried, tested and proven viable. Indeed for many decades in the first half of the 19th century many British towns and cities actually used centrally-powered electric trams and buses (trolleybuses), their demise came because motor buses were cheap to purchase (short-term headline costs delighted the financial bean-counters who did not care that these came with more expensive maintenance costs and shorter overall life) and whilst air pollution was a known topic it was seen as only applying to smogs caused by burning coal. It was also thought that cars and other road traffic would flow more freely with motor buses - this being thinking which is now known to have been erroneous, and trams have returned to a few of our urban areas. (Too few!)
With trolleybuses the possibility will always remain that if there should be an emergency situation (such as a burst water main) then the bus is still be able to go around the obstruction - or even disconnect from the power supply and use its temporary onboard power solution to deviate via other roads.
Electric Buses Are P o p u l a r With Passengers!
In Arnhem, Holland the transport operators saw ridership increases in the order of 17% on routes converted from diesels on a "like-for-like" basis. Their five year "Trolley 2000" Trolleybus Rapid Transit (TBRT) strategy was conceived knowing that by using trolleybuses the number of passengers travelling by bus would rise by up to 21% higher than could have been expected using the best type of diesel buses. In Salzburg, Austria ridership increases have been 16% and the city is part way through a long term trolleybus expansion project with the intended aim of the near total elimination of fossil fuel powered buses from its streets. This is being done for environmental reasons.
|Salzburg, Austria takes air pollution issues seriously and is converting more diesel bus routes to electric traction, with the aim of a near total elimination of fossil fuel powered buses from its streets.
This image shows one of the new (in 2012) Metro styled trolleybuses with a sloping tram-like front at the bus station which is next to the main railway station. Plus the trolleypoles from another trolleybus!
Image & license: Ralf Roletschek / Wikipedia encyclopædia GNU FDL 1.2
Salzburg has found that it takes just 18 months to convert a diesel bus route to trolleybuses - including all the planning and installation works.
|In Arnhem, Holland the "Trolley 2000" transport plan has seen the creation of much reserved lane transport corridors, giving buses the same degree of priority and protection from traffic congestion as other cities give street running trams / light rail.
Note the special (white / amber / red 'dot') traffic signals - a feature usually only found on tram systems. (This image shows the signals in white dot mode - click the image to see more easily ).
Arnhem has found that a service which is busy enough to justify a bus every 10 minutes - six buses an hour - is cheaper to operate with trolleybuses than motorbuses.
Given A Choice, Passengers Vote For Electric And Against Diesel Buses
Only one city is known to have ever actually asked its passengers their modal choice preference. This was San Francisco in the USA. Their passenger survey found that whilst the streetcars (trams) are the overwhelming 1st choice - even for routes where they are not a viable proposition - the electric trolleycoaches* are considerably more popular than the motorbuses, which are actively disliked, being rated as noisy and smelly. Indeed when roadworks caused temporary motorbus substitution of some electric bus services (with service frequencies and journey times remaining unchanged) there was an 11.33% downturn in passenger patronage that can only be explained by passengers making a pro-active choice to avoid the motorbuses.
*In North America many people refer to what we call a trolleybus as a trolleycoach.
San Francisco, USA - passengers like their electric street transports (modern streetcars, historic streetcars and trolleycoaches) - and given a choice pro-actively avoid motorbuses, which they rate as being noisy and smelly.
Along with reduced air pollution another advantage of the electrical power supply infrastructure is that it would act as a continuous advertisement for the system and help instill confidence that the transport will be here today - and tomorrow(!), thereby encouraging businesses to make investments in the served corridors.
Sparks Effect Attracts British Passengers
Here in the UK experience gained from railway electrification has shown that the sparks effect does attract more patronage, even when (as in Yorkshire) hostile Government policies meant that the passengers had to use 30+ year-old hand me down trains. Based on this plus the experience in America, Austria and Holland quoted above it is reasonable to expect increases in passenger numbers on any British diesel bus routes which are converted to electric traction.
The reasons why passengers prefer electric transports include that their better overall performance, less vibration (none whilst idling!) and lack of engine smells results in a faster, more comfortable, smoother and hence more attractive journey experience.
Cost-Effective For Bus Operators!
Being cheaper to operate and having a longer vehicle life means that for high-frequency, high-capacity services the whole-life costs favour trolleybuses over diesels. Other advantages include:
Potentially Financially Beneficial for NHS, Treasury and UK Taxpayers!
Admittedly there is a challenge in that HM Treasury and most of our City-quoted transport groups are only interested in finances which involve the lowest headline costs in the shortest possible term and highest immediate profits, rather than what works out to be the most cost effective over 15+ years. This needs to change!
London Buses Ltd in its 2001 publication "Cleaner Air for London - London Buses leads the Way" estimated that the cost of (human) health care which results from diesel bus air pollution equates to an equivalent of 13 pence (approximately €0.20 [20 Euro cents]) per kilometre. Meanwhile, a report prepared at the Roma Tre university in Rome, Italy, suggested the cost as being €1.20 per km. As most readers will instantly note, the Italian figure is significantly larger! Using this figure helped justify the investment in a new "filobus" (the Italian word for trolleybus) service along a severely air polluted transport corridor in Rome. In short, it suggested that installing the electric street transports would result in significant financial benefits (through reduced health care costs) to the Italian NHS - and by extension to the Italian Treasury and to Italian tax-payers.
The clear implication here is that investment funds spent here in the UK on the electric street transports will save our NHS money... year after year. Furthermore, if it means that fewer family breadwinners become unwell then it will result in people who would have needed social security benefits remaining in employment as tax payers. Fewer incidences of ill-health also result in many emotional and familial benefits which cannot be counted financially.
Sourcing The Energy
The electricity to power our electric street transports has to come from somewhere and since humankind does not (yet) know how to cleanly and safely extract it from the Ether so it is frequently sourced at coal, natural gas or nuclear power stations or from renewables - solar, wind, wave, hydro, geothermal, etc. The European canals which in the first half the 19th century used overhead wire electrification for electrically powered barges sourced their energy from sluices / turbines at the locks.
At one time wind generation was believed to represent the best of the renewable options for us in the UK, however whilst it probably is viable for low-power domestic micro-generation, real-world commercial experience has shown that triple-bladed wind turbines rarely meet the generating capacity expectations that their promoters promised. It is very likely that someone, somewhere, has devised a commercial wind power generation system which actually works far better than the three-bladed wind turbines upon which so many people (mis-)place their faith.
Just because the UK is facing an energy shortage is not the reason to avoid replacing buses that emit much harmful fossil-duel derived air pollution into our urban environment (ie: the streets in which we live and breathe) with clean electric buses and trams that do not emit any tailpipe pollution at all. Of course it would have been better if the British electric generation and supply industry had benefited from proper long-term planning so that the energy shortage had not arisen. It is indeed total insanity that existing coal fuelled electric generating facilities are being withdrawn without first ensuring that there will still be sufficient generating capacity - whilst it is recognised that coal is a dirty fuel the fact remains that it is still far easier and more effective to scrub waste gasses from the comparative few coal power station chimneys than the many thousands of vehicle tail pipes.
Many people see much potential in low-carbon energies such as anaerobic digestion (AD) biogas and bio-methane as sources of energy for use at power stations - in every case even if there is some chimney waste it will still be significantly less damaging to our health than diesel fumes in our streets, lungs, bloodstream, brain, etc.
Even When The Electricity Is Sourced From Fossil Fuel
|In August 2003 the Swedish town of Landskrona opened a completely new trolleybus service which had been successfully designed and installed in just
one year from when the city council voted for it!
What a contrast this makes with the British planning process which encourages paralysis by analysis!!!
Image & license: Carl-Johan Aberger / Wikipedia encyclopædia. Public Domian.
|As part of its plans to reduce severe urban air pollution the Chinese government is encouraging its cities to invest in electrically powered trams and trolleybuses.
This new Beijing trolleybus has just connected to the overhead wiring after travelling on a short unwired section of route, as described below.
Image & license: N509FZ / Wikipedia encyclopædia CC-BY-SA-4.0
Short Wire-Free Sections With Recycled Energy
It is possible, if absolutely necessary, for both trams and trolleybuses to use onboard energy storage to travel along short sections of unwired roadway. Typically this could be done at very busy junctions where many routes meet and diverge, as an alternative to installing what would otherwise be very complex overhead wiring. Since capacitors are expected to last the entire life of the vehicle then these could represent the preferred medium of energy storage.
Many of the latest designs of trolleybus (and some modern trams) are already fitted with capacitors which they use to reduce overall energy consumption by storing braking energy so that it can be recycled (re-used) when accelerating. They use capacitors because these are significantly more effective than batteries at this function.
A Study For London
The Electric Tbus Group has conducted a detailed study which suggests that for London the conversion of the busiest bus routes (eg: those with a frequency of every 5 minutes or more) would offer significant financial and environmental benefits. Thanks to the network effect where multiple routes operate along the same roads the situation would soon arise whereby many subsequent conversions would entail less additional wiring - both increasing the cost effectiveness of existing wiring and reducing the cost of the electrification of additional routes.
Plus of course Londoners would benefit from the significantly cleaner air in the streets where they live, work and play.
Trolleybuses, electric buses, air pollution and why so called "cleaner" diesel (aka "less dirty")
buses could be worse that buses which give off visible smoke are looked at on the Electric Buses pages from the "citytransport.info" website.
citytransportinfo is also here:
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