I suppose it all depends on what you are comparing it to - HSR uses a lot of power - less per person than aircaft, but not necessarily that much less than a car, especially if it has passengers. Much depends on assumptions about who will use the HSR, in particular whether it will displace existing car/aircraft movements, or generate new 'journeys'.

Its the knock-on effect I would have concerns about, and this depends on many issues, including the chosen route and station location. In France, the lines mainly link in with existing stations in city centres, and in doing so help the process of increasing the density of urban useage and reducing the need to own cars - or for that matter, to use much internal flights, so there is a postiive impact.

On the other hand, HSR can also promote unsustainable urban patterns. The High Speed line in Taiwan (it runs down the west coast) is a case in point. At the northern end, in Taipei, it has become a major focus for public tranport and more dense usage of land near the station. But to save money, as it went to the south, the line runs inland, with stations at the edge of cities like Tainan. This has resulted in a move away from traditional city cores, and has resulted in more sprawl around the stations.

Although its unpopular to say it, if HSR became a business focused line ferrying the weathy between city centres the carbon benefits would probably be quite high, as it would stop the high profit end of internal flight. It would also force the existing lines to compete on price (i.e., they would try to stuff the trains with plebs, on the Ryanair model), which would act to displace a lot of car travel, especially by people currently put off the train for reasons of cost. It would also greatly increase the desirability of living and working in city centres within easy reach of major train stations.

From what I've seen of the plans, I suspect HS2 will end up being a bit of a fudge, with lots of poorly located train stations aimed at wealthy commuter town customers, and with a mix of carriages - i.e. it will, if anything, encourage unsustainable patterns of commuting and travel.

The British cant plan shit nowadays....long gone are the days of our organizational prowess that was sufficient for Hitler to seek a truce

Some thoughts:
1.any form of mass and fast transportation is energy hungry. So unless we all stop travelling or revert back to horse and cart, we need to have a wider range of criteria to make decisions.
2. Trains are more pleasant than planes and the security risk is lower. Therefore getting on and coming off the train is considerably more straightforward than taking a plane.
3. You can walk around on trains, less so on planes, especially short haul.
4. The carbon footprint of HS2 appears to be up for debate. fair enough. However we know exactly what environmental price we are paying for flying - and (in my case) for driving to the airport.
5. Surely it can't be worse than flying????
6. Trains are more ubiquitous than planes so it is easy for local residents to be against new train projects. But planes crisscross overhead all the time and we appear unconcerned. The damage they inflict is therefore unseen. However those who live near airports have a much more terrible time of it.
7. Surely we can't be suggesting increasing Heathrow's capacity or building yet another hub. It makes more sense to have a high speed rail line with efficient connections for onward journeys to take the pressure away.

If you also include the carbon involved in construction, its difficult to see how a high speed line can possibly offset its total carbon use through some reduction in car and plane travel. Its not as though all other modes of travel will be banned.

How about a compromise. If HS2 is built is must be run solely on wind produced electricity. Trains might be a bit slow at times, but think of the smugness rating of the travellers!

As a frequent traveller on the west coast main line between London and Manchester, I'm struggling to see how a whole new line could be justified on capacity grounds. Some peak time trains are over-crowded, but longer trains and improved signalling to run more frequent services would seem a much more cost efficient option.

But I believe this has been sold more on the premise of increased speed. If the cost of travel on HS2 proves to be higher than existing rail lines, (for example) because of the need to recoup cost or because other lines will cut pricing to meet the new and faster competition, then I also struggle to see how this can be designed for anyone other than business travellers.

I would then be interested to see how many business travellers actually travel between London and Birmingham/Manchester/Glasgow/Edinburgh on a weekly basis (assuming the line is extended as proposed) by any form of transport. I would be very surprised if the total number justifies a brand new line of this level of expense.

In my view, at present the UK is neither large enough (France/China) nor densely populated enough (Japan/Korea) to warrant a high speed line of this nature. And I don't believe that a dubious and possibly very small environmental benefit is a good reason for committing to spend billions right now.

Just to throw in there, the mainline to South West England isn't even electrified yet. And there are parts of the network that are using single track lines. My point is that, whilst the railway network does definitely need investment, I think it could be better spent improving what we've got than taking half an hour off the time it takes to get from one big urban centre to another.

HS2 is not primarily about high speed - it's about increasing capacity, which is currently very tight on routes northwards out of London. This will allow greater flexibility in running and reduce the knock-on effects when something goes wrong, so will increase reliability of services. It will also give people greater choice. These effects, in turn, will make it a more attractive travel mode so will attract people who would otherwise have driven or flown.

Having said that, if you are going to build a new line it doesn't cost much more to make it a high speed line, so you might as well do so.

In other words it will reduce CO2 emissions significantly, but not by virtue of the fact that it's a high speed line.

Its a lot easier to manage the carbon emmisions from a handful of powerplants, than a fleet of aircraft and millions of cars. A lot easier to setup carbon sequesterisation and replace the fuel with better, more friendly energy sources as they become available.

something else to add in- would the new high speed line increase the capacity for freight on the current lines? if so, this could reduce road-freight levels, further cutting carbon.

possibly. these things are a little complex.

People want to travel, and I think they will travel. I think it is far preferable that people travel by plane than in cars or planes, so I think we should support high-speed rail.

From a CO2 point of view there's little difference between cars/planes and high-speed rail powered by coal stations - but we need to decarbonise our electricity supply anyway, so we'd better get a move on with that.

birmingham-london trains are currently jam packed and there are three an hour. Extra capacity is definetly needed

@ MiaErdman
I totally agree with your post.

Given that we are facing ever increasing fuel prices as oil becomes more scarce, we should be investing in extending the entire rail network. Open up the branch lines that were so recklessly closed by Dr.Beeching. When it is no longer economic to drive cars and trucks, we will need to use the most efficient alternative to road transport. Rail freight should be developed in readiness for the decline in oil stocks.

Once again we see under-investment in the national rail network as a result of privatisation with contracts of uncertain length curbing real advances in rail transport. We still operate on the same rail system designed I.K. Brunel. Spending a huge amount of money on an ultra fast service would seem to be extremely indulgent and shortsighted as to what is really needed.

these trains run on electricity........... where on earth do they think this electricity is coming from?

I can tell you it will effectively eliminate a major nature reserve, threaten chalk streams, demolish and divide ancient woodlands, impact rare butterflies and roll over an area of outstanding natural beauty.

There will be a huge supporting infrastructure of additional roads and years of complete disruption to local road systems.

But that's all alright for the Guardian commenters - yes we're all Nimbys, a 22 metre wide high fenced double rail route is not as bad as a road, etc, etc, etc.

Well, you wouldn't build this across the south downs, over dartmoor, the lakes or the peak district (oh, wait: The chilterns is just rubbish landscape).

Really, you're just saying you can build anything anywhere as long as it reduces carbon. Nuclear power plants for example.

Please could the money first be spent on providing local rail travel solutions - such as reopening the Wealden Link between Lewes and Uckfield in Sussex? These lines would encourage more motorists to take the train instead.

I love public transport but HS2 is a huge, huge white elephant.

It is a rich man's vanity project.

It's great that £32 billion is available to invest; let's use it where it will have a real impact.

Thanks for the comments so far. Some early reaction via Twitter, including from Christian Wolmar, the transport commentator...

@christianwolmar No.govt own assessment suggests carbon neutrality, and depending on source of power,cd be rise

@dpeilow the answer to that is unequivocally yes when the network goes far enough north to shift people away from flights.

The figures from HS2 Ltd's own traction Energy requirements guide and their expected figures of which form of transport HS2 passengers have transferred from

The kilowatt hours per seat kilometer for HS2 is about double that for present NINE carriage Pendolino and would be more if Pendolino were extended to 11 or 12 carriages

HS2 say that 65% of the passengers will have come from the existing rail

by simple maths that seems to suggest requiring 30% more kilowatt hours per seat kilometer and without "greening up" electricity generation ALSO 30% more emissions

@EGriff

Did you actually read the other comments before you wrote that?

And, in the decades ahead, how will the electricity used to power the trains be produced?

Gas-fired power stations seem to be the favourite. Relatively easy to build, cheaper and less polluting than than coal, and no shortage of fuel sources.

As to using HS2 as opposed to domestic flights from Heathrow
In Atkins report 5082342 WPO – Impact of updates April 2011( produced for HS2 Ltd) there is in para 2.1 of the technical note the following

as for the vast majority of people accessing Heathrow for domestic travel would not originate in the HS2 catchment area and therefore HS2 would not be a viable surface access option

I just received this response from Mike Childs, Friends of the Earth’s head of policy, research and science...

If we’re going to cut emissions from transport to help tackle climate change, people need cheaper, greener alternatives to flying and driving. Faster rail services sound like the perfect solution, but the Government admits that current High Speed 2 plans will do little, if anything, to cut carbon. Given the amount of money that HS2 would cost, and the urgent need to cut emissions, the Government would be better off improving the rail services we’ve already got, enticing people out of cars and planes and enabling them to benefit from faster, reliable and more affordable trains.

They should be given the project to run local trains on time.

I donot think every one is bussing between Glasgow and London. Most of people travel may 100 miles or so. Then most of people are travelling to work and it is here where efforts should be aimed at.

How will it help if some one travels from Glasgow to London in half the time then spend few more hours reaching his/her destination travelling few 10's of miles.

You don't have to be a green activist to realise that we are somewhere near peak oil.

Cars and Planes are dependent on oil and are likely to be for the foreseeable future.

Now we may crack it and produce long range electric cars or hydrogen cars, but in the meantime rail offers the only proven way foreward, in that we know we could power the trains with renewable/ nuclear / coal generated electricity.

It would seem neglegent to wait untill we were in the grip of an oil crisis to start increasing our rail capacity..... but knowing Britain

Why would it for it to be High Speed means it will have few stops so a means to get to places its rubbish unless its only the major station concerned you want to get to and they already have rail links. Meanwhile I now its going to come as shock the CIF , but people very rarely want to or indeed do drive from anywhere in the Midlands or the North into Central London so there is not just traffic volume to cut down on in the first place.

Endorse OOkeyman's comment about freight- the West Coast Main Line despite the massive amount spent on the recent upgrade can hardly cope with potential freight demand and usage as diesel goes into the stratosphere. Adoption of the promising Cagrobeamer model, currently being tried in Germany also will make rail more economical for freight.

It is the time scale of the project which worries me an we do need to look for some quicker wins with more local impact such as Uckfield-Lewes- mentioned above, the Todmorden and Ipswich curves and greater progress on Ipswich- Bristol- this is the kind of strategic infrastructure spend we need to get traffic off roads on to rail and reduce our dependence on imported oil from some distinctly unfriendly suppliers. Also the Woodhead line to reduce the nightmare of the M62.

Supporters say HS2 will reduce the number of domestic flights in the UK, but critics say it could increase net emissions

Then that's that. The best the nimbys and their allies can say is "could".

We are constantly hearing about the benefits that high-speed rail provides in other countries and when visiting them, we experience just a few of these benefits for ourselves.

Let's push ahead with this.

Before HS2 is started, it would be good to see some important bottlenecks on the current rail system removed. For example, building a second bridge alongside the Digswell Viaduct in Welwyn Garden City would prevent the four track East Coast Mainline being reduced to just two tracks to cross the River Mimram.

Evidence from western Europe where inter-city flights have flatlined with the development of HS rail, suggests that it is when journeys are cut below 3hours that they become more attractive to business users than flying - hence the importance to extend HS2 to Leeds and on to Glasgow/Edinburgh.

@egriff: I am always interested to find out from those protesting about HS2 (I live near the proposed route) how many flights they have taken in the last few years and if they are aware of the environmental cost of aviation: of course, emissions that may be perceived only as affecting other communities and other parts of the world are not nearly so important than something in your own backyard.......

A far better way to reduce transport emissions would be to build urban rapid transit systems, as they are doing in all the countries that also have high speed lines.

Capacity on the London-Midlands corridoor could be greatly increased by rebuilding the Rugby-Aylesbury section of the Great Central, at a fraction of the cost and in a fraction of the time.

Divert the money from HS2 to these, and you would have far more economic, social and enviromental benefits.

We dont need a brand new line to get air passengers to switch to trains in the UK - finish the upgrades of existing lines instead, and London-Glasgow/Edinburgh become under 4 hours, which is very competitive with air.

@ devoxbelg - makes sense. Maybe we should be building the money to build Walt Disney's real EPCOT (Experimental Prototype Community of Tomorrow) - a city where you took PeopleMovers and Monorails to work, and cars and trucks drove underground - if you owned a car it would be just for weekend pleasure trips.

You have to coach this question in the context of a number of years. That is,
over a 25 year period between an installed HS2 and the status quo (without HS2) will HS2 lead to carbon reductions in tranport?

Chances are yes.

Over say five to ten years probably not. The carbon cost of installing and then using reduces over time.

The crucial question in the context of Britain is, if it's privatised and run for profit then extortionate fares will reduce its appeal dramatically and lead to less journeys being made by HS2. It will then be a profit/cash cow and much less of green mode of transport. This mode of deployment skews the entire discussion.

A 400 km/hr railway has serious implications for energy consumption because energy use increases approximately with the square of the speed. At 400 km/hr a train will use 4 times more energy then at 200 km/hr. This is difficult to reconcile with the UK’s energy conservation and carbon reduction targets.

The environmental impact of the route is exacerbated by a 400 km/hr design speed which requires a virtually straight alignment that carves through the landscape. It’s hard to imagine a more environmentally destructive alignment than that selected through the tranquil Misbourne Valley.

Any new railway should follow an existing corridor like much of the HS1 line through Kent, which runs alongside the M2 and M20 motorways. It should travel at speeds that provide appropriate and not necessarily the fastest journey times. And it should be compatible with our existing railway track and rolling stock as part of a fully co-ordinated and integrated network.

High Speed Rail can make a significant impact on domestic air emissions in the UK, once it takes sufficient market share from the airlines. In order to do this, it has to offer attractive journey times. That means high speeds and non-stop long-distance services.

There are approximately half a million passengers a month flying between London and Scottish airports. Air has around 82% of the market and this is one of the busiest air routes in the World. These passengers value non-stop, fast connections between these locations. Indeed, such short flights enable short business and pleasure trips that are otherwise not possible. Even many otherwise eco-conscious people are seduced by the convenience of flying.

The HS2 proposal should therefore be viewed as the first part of a comprehensive national network - one that continues to Edinburgh and Glasgow. Once that is in place, journey times of under 2 hours between the capitals of England and Scotland will be possible. This sounds fanciful, but is possible if using the 400 km/h (250 mph) trains that are now being demonstrated in the countries that are much further along in rail development than ourselves. Right now France, China, Korea and Japan are all developing 400km/h or faster trains. These will be in service during this decade, long before they are needed for Britain's HS2. This is why HS2 phase one needs to be built for such speeds from the start.

Emissions from track construction are not insignificant and are often overlooked. This needs to be considered in any analysis of the emissions per passenger journey. The more passengers that use the route, the lower the emissions per passenger. High Speed Rail needs to win as many passengers as possible from other modes to "dilute" these emissions over the lifetime of the track.

With such short journey times, High Speed Rail can win most if not all of the current air market from London to the North of England and Scotland. This has been shown again and again over other similar routes around the world. Analysing the traffic levels on each route, we arrive at a potential for CO2 emissions saving of between 3 and 6 times that of air between individual British city pairs, even with trains running at 400km/h. These figures use today's standard UK National Grid CO2 emissions - they do not require renewable energy to achieve these savings, which only serve to reduce emissions still further.

In addition to renewable energy being used to supply the trains, new developments - such as carbon negative cement - also serve to reduce construction emissions, which will surely be incorporated into the project before construction begins. These developments can make a dramatic reduction to overall per-passenger emissions.

Taken further, a simple link allowing HS1 to connect with Heathrow enables short-haul passengers to the near continent to be shifted to trains. This also allows transfer passengers to continue by rail. Doing so reduces emissions still further, and it appears that by redistributing flights around London airports in a more even and logical manner would completely removed the need for further expansion at Heathrow. But that is another discussion. Nevertheless, a simple interconnection between HS1 and HS2 and the next generation of faster trains allow competitive through journeys such as Birmingham - Paris or Manchester - Brussels, removing yet more flights and more emissions.

There are many myths being propagated about the high speed line, such as it will take a 75 metre swath of the countryside - it's closer to 15 metres - but undoubtedly if the government holds its nerve then the line can make a major contribution to reducing transport emissions.

Further details on these topics and derivations, explanations and sources for these numbers can be read in this independent document which takes a more detailed look at the issues around HS2.

Even the most avid proponents of HS2, such as Jim Steer, admit that the only reduction in emissions comes from potential knock-on effects, notably freeing up capacity on existing lines so as to attract more car users onto conventional rail services. This ignores other potential knock-on effects, such as greatly increasing the demand for transport between London and Birmingham - effectively making them 1 conurbation for those who can afford to shuttle back and forth at will.

It has become, as Eddington warned, a "grand project" where logic breaks down and arguments are distorted in order to justify it regardless.

The whole area of energy consumption in the transport sector needs to be tackled in a joined up way. Urban transport and short journeys make up the bulk of it. Medium distance travel, such as Exeter-Bristol, Manchester-Birmingham, come second. Then there is freight - railways are 3 times as efficient as road, but we could make much greater use of canals and coastal shipping - which is more energy efficient than rail by a further factor of 3.

HS2 is not the best way to free up rail capacity. The danger is that HS2 mania will carry all before it, and other transport needs will be neglected to pay for it.

@dpeilow

The flaw in your argument is the effect of much higher oil prices in 25 years time, and the need to anticipate that in its full context. It doesnt just mean that short haul air becomes less competitive with electric trains running at 125 or even 140mph. It means that we will be living in a different world with very different priorities. What you are saying is todays problem/opportunity but the solution will be here in 30 years time, if all goes to plan, which it wont.

The age of cheap oil and easy money are over. Climate change will kick in too. The line will never reach Scotland - perhaps it should start there.

Back in the here and now, the effect of removing most of the domestic short haul from Heathrow would be to free up slots for more flights elsewhere, so no reductions there.

Bring on the carbon negative cement though.

Oh dear - more grossly misleading assumptions right from the off

1. The 400km/h headline speed figure - although the line will be engineered to permit trains travelling up to 400km/h, this is simply in-built future proofing. Something we should welcome given previous major transport infrastructure debacles. If, for example, someone had had the forethought to construct the existing motorway network with a strip of vacant land down the middle, say 25m wide, we wouldn't be having a discussion right now about the planned route of HS2? Fact is, using current technology the planned HS2 trains will run at 320 - 360km/h. 400km/h trains will only emerge when technology has advanced sufficiently for them to operate using the same energy currently consumed by their 320km/h predecessors, so please put away your calculators and equations about energy use increasing exponentially as speed increases.

2. Planned Stations A major criticism aimed at HS2 by those viscerally opposed to the project, primarily because it goes through their back yards (although they're clever enough not to admit that up front) is the lack of stations - ie. not serving intermediate stop traffic originating in smaller towns and cities - so the idea that there will lots of stations is flawed. The present plans, including phases 1&2 (the whole Y shape thing) incorporates;
An interchange station just outside London - Old Oak Common
A station at the NEC/Birmingham International Airport
A South Manchester hub station, almost certainly at Manchester Airport
A city centre Manchester station
A station at East Midlands (Airport?)
A South Yorks station (Sheffield city centre?)
A station in city centre Leeds
so either city centre or existing transport hub/interchanges - not parkway stations in the middle of nowhere (a la Haute Picardie) generating lots of extra traffic.

3. Obssession with speed, ie. saving a few minutes - it's a pity the line was labelled HS2 because HC2 (as in High Capcity) would have been more apt. The new lines primary raison d'etre is solving the capacity shortfall time bomb ticking away on the WCML. Speed is the cream on top, driving modal shift away from other more carbon intensive forms of transport, particularly short haul air.

4. HS2 as a domestic project - High Speed Rail (HSR) viewed as an exclusively domestic transport strategy doesn't really work - that's why HS2 isn't just a domestic project. HS2 will incorporate a direct connection to HS1 via a tunnel from Old Oak Common to the junction just north of St. Pancras (actually underground via the existing NLL [North London Line]), faciltating direct services between the near continent at UK provincial cities from day 1 and seamless transfer on to the burgeoning network of HSR services now emerging. When HS2 comes fully to fruition, the HSR network will extend to Sevilla and Naples southward, Bratislava and Berlin Eastward and perhaps to Stockholm Northward, via the Fehmarn Belt Fixed Link - the Gotthard Base Tunnel will also be complete, opening up much of Southern Europe. In short a critical mass of new HSR lines will be in place, enabling HSR to challenge the supremacy of short haul air as the transport mode of choice for most intra-European travellers, business or leisure.

5. Premium Fare Structures It's lazy to assume that services planned for HS2 (or even HS1 for that matter) will attract premium prices. All new rail lines across Europe must now comply with European Interoperability Standards, facilitating direct competiton between different providers on the same line. The first example of this on UK shores will be the forthcoming Deutsche Bahn (DB) service between London St. Pancras and Frankfurt/Amsterdam - what do you think will happen to Eurostar fares when their current monopoly is broken in two years time (start date for the DB service is 2013) - somehow I think they'll be going only one way - down!

6. Target Markets Another easy (lazy) target for anti campaigners are the claims that HS2 is simply for "fat cat expense account fuelled executives" but this is an utterly bogus assertion on their part - in fact 70% of the forecast traffic for HS2 emanates from non-business sectors, so just another myth propagated to deceive public opinion?

7. Upgrading the existing network Finally the old chestnut everyone likes to trot out - firstly there is no pot of money right now to reverse the Beeching era network cuts, 95%+ of HS2's budget is for 10 years hence, NOT NOW! In short, the existing network IS being upgraded

padav what capacity time bomb , outside the rush hour their is no capacity problem and even in the rush hour HS2 will do virtual nothing for the real capacity problems seen which are shorter commuting trips into the major cities . And without any new stations your limited anyway to how many trains you can handle no matter how many lines you have and the problem here is were do you actual put these new stations given that the places people want to go to are already virtual full ? As a way to deal with existing capacity issues HS2 is frankly rubbish.

And frankly you seems clueless as to way people object to having a high speed line going past their house when there will be no benefit to them there will be no stations near them.

'HS2 as a domestic project ' It is and just that like a lot of people on CIF you simply ignore the fact that the majoiryt of people do not live in London so for them to use these rails lines to travel within Europe rather than fly means extra time and extra cost , because they run via London . That is already an issue with Eurostar, HS2 will repeat the same problem .

The energy consumption issues become irrelevant once you spam sufficient nuclear reactors.

Given the length of time to build the line (2026 to Birmingham, 2032 to Manchester), anyone trying to assess the project has to consider long term trends. Two big ones are peak oil and Moore's law which might pull in opposite directions.

1. Peak oil - by these dates it is quite possible that liquid fuels in general will be growing scarce and more polluting at the same time, as the supply of conventional oil declines and an increasingly larger share of liquid fuels comes from unconventional sources such as tar sands. A flight fueled from tar sands has effectively triple the carbon footprint, making even a coal-fueled electric train a clear winner.

2. Moore's law - it's hard to appreciate just how fast computer technology is improving even though we are all witnessing it. Consider that Wikipedia is only ten years old, the first smart phones are only a few years older, and just twenty years ago most people had not yet heard of the World Wide Web. Progress in computing shows no sign of slowing down for the foreseeable future. Thus we can expect further progress in the twenty years to build HS2 comparable to all the progress in computing of the last twenty years. And the last twenty years, again, started out with no Web, and with very few people who could have imagined what we have now. Presumably computing twenty years from now will be similarly unimaginable today. Perhaps by 2032, at least for business travelers, there will be little they can accomplish by getting on a train that they could not accomplish faster right wherever they happen to be already. By then nearly the entire workforce will have grown up with social computing and whatever comes after. In the 2030s computers may be capable of conversational speech and convincing telepresence which could make the need for travel redundant.

I haven't seen much hint that anyone in the transport industry begins to comprehend what impact further progress in computing could have on the need to travel. Instead the assumption seems to be that people will just need to keep on traveling more and ever more forever, and long-term infrastructure planning can be safely based on these projections.

The combination of peak oil and Moore's law could wipe out the airline industry in a few decades. Trains will probably last longer, if only because of the continuing need to move freight.

Impact on total emissions is going to be dependant on how many will use the service and therefore will depend on cost of the tickets. Cost of the tickets will be high in order to pay for this monstrosity, either that or we will pay indirectly in the form of very large subsidies. The economics of this project are based on a large gamble, making assumptions about the future economy and willingness of punters to pay the higher prices. I and many others will never use the service in protest at the stupidity of the project.

A report written by a company with potentially massive gains from the outcome of the findings is not to be trusted. Politicians in the main are numerically illiterate and are unfortunately very susceptible to lobby groups.

A word on environmental issues:

A 75m wide strip of earthworks, concrete and metal across the country is hugely carbon expensive. Anyone who says otherwise is deluded and needs their head examined.

Figures used for CO2 emissions during operation are wildly optimistic due to the complex issues surrounding electricity generation and supply (discussion for anther day).

Wind resistance increases proportional to speed squared, it therefore goes to say high speed is not good for the environment. If we want to reduce emissions we have to make sacrifices, we can't expect to continue with our present quality of life, optimising convenience at the expense of the environment.

All the gloss and spin thrown at this project cannot escape the laws of physics and fundamental economics.

By the way, I am not a 'nimby', I am lucky enough to live far away from this white elephant. I pity the people who will have to look at and hear this lunatic vanity project every day.

Some very simple points that show that Green is not the aim of this project.

The focus has been speed all along - so the lines are straight and do not take into account communities or countryside. Speed = higher energy use and devastation.

This is not going to reduce flights - it may reduce a relatively small amount of internal flights (HS2 predict only about 6% of their passengers will come from modal shift from air). All those flight slots will be replaced with longer flights, increasing carbon anyway.
Just the building of it has massive carbon implications.

Part of the business case for HS2 ignores a very key thing:
the use of technology to work while travelling or to work without travelling (eg. teleconferencing)
Without these being excluded the business case starts to collapse.

They predict a large % of their passengers will travel just because HS2 will exist and that another large % will be leisure travel - neither of which should be encouraged and subsidised by the government

No one can answer the question yet about where the energy will come from but we know some power stations are coming to the end of their life cycle so the added burden of powering HS2 needs to be clarified . They do know however that there will be substations every 2km along the route.

Finally, a critical issue is the government has already shown a disregard for appropriate mitigation, a key environmental issue along the route and for the country as a whole. Tunnels are used on only 10% of the route though all their pretty pictures have included tunnels and countryside. They have not produced any images to show how it will look when it runs above ground though highly populated areas next to parks, schools and homes. This is the image of HS2 they want to hide in terms of mitigation, environment, compensation and everything else. As the next stage of the route is revealed in 2012 (after the consultation) more communities will release the degeneration they face.

The DfT has ruled out tunnels in the most populated areas and just last week told the Transport Select Committee they may not tunnel other highly populated areas either.

On the carbon front, once a train gets above around 125 mph its energy consumption goes up sharply. Using electricity from the grid, a London-Edinburgh train going at 350km/h (217 mph) would consume the equivalent of 22 litres of fuel per seat. An Airbus 321 consumes 20 litres.

[Roger Kemp, 'Transport Energy Consumption’, Lancaster University, 10 Sept 2004 (citing his earlier work ‘Environmental impact of high-speed rail’, Institution of Mechanical Engineers, Seminar on High Speed Rail Developments, 21 April 2004].

There is a multipliclation of 1.3 to add for radiative forcing, but that's still not making the plane much worse than the HS2.

The emissions will go down as the grid goes greener, but then HS2 is adding to demand from the grid. That new demand will be provided by the generators with spare capacity, ie coal-fired power stations. Until we have a 100% renewable grid with spare capacity, we should calculate HS2's additional demand emisions based on coal generation, as that's where it'll be coming from.

There is also HS2's higher per-passenger emissions due to low occupancy. The HS2 will be expensive, plebs will still travel on normal lines. To get a foretaste of HS2, look at first class carriages on current trains. Divide the carbon emissions of the carriage bewtween the five or ten occupants.

The hope of HS2 providing a reduction of domestic flights may well be something of a red herring. Once you factor in the check-in times and the travel time to airports outside cities, it is already quicker to get the train between London and Leeds or Manchester. A large number of 'domestic' flights are actually connections to international flights. Outside of stations in airports, HS2 won't attract such travellers. Even those fliers won't all shift over. Why would you make a more fiddly travel plan with no carbon or cost saving?

The real bang for our bucks on reducing emissions on the railways would come from electrifying the whole network. But that doesn't give politicians a transport equivalent of the 2012 Olympics to stand in front of going 'look, shiny!'.

@devoxbelg

When oil prices are much higher in 25 years time, this will only serve to widen the gap between those competing transport technologies that waste oil and those that use it more frugally. In that I include the comparison between air and high speed rail, as they offer similar wider social and economic advantages. For the market we are talking about, conventional rail does not.

Countries that anticipate this widening and develop a long term transport strategy to deploy transport technologies that can run on zero oil - which includes High Speed Rail - will be at a significant advantage to those that don't. The benefits of increased mobility and shortened journey times will not go away, even in a post-oil era and especially if your competitors have them.

Yesterday Russia announced their approval of a 400 km/h line between Moscow and St Petersburg, a distance only slightly longer than London to Glasgow. Like other oil rich states, they are already using their revenues to prepare for the day when the inevitable happens and it runs out.

If, as some advocate, we just build another equivalent railway to what we already have, this will do nothing to convince the vast majority of passengers who value a sub-2 hour journey time from London to the North and Scotland to move away from air. When the time comes that those passengers can no longer afford to fly and the only alternative they have is to take a 4 or 5 hour old-fashioned train journey, then business suffers and the leisure industry sees far fewer short breaks. By acting now, it doesn't have to be this way and the benefits we are accustomed to can be maintained.

Conventional speed trains may use less energy per mile than high speed types, but the tracks the run on will produce very similar construction emissions as HS2. If, instead of capturing 80% of the London-Scotland market, the project only allowed 40% market share, then the per-seat emissions from the track construction would double. Furthermore, fewer trains can carry the same number of people in the case of high speed rail. Conventional rail can therefore have an equal or worse emissions figure than high speed rail when the system as a whole is considered. It does not make sense to build a new railway that is unattractive to the majority of passengers, thus failing to win them over from road and air.

By not building projects like HS2 and making a shifts to transport technologies that do not require fossil fuels, the UK would be condemning itself to be vulnerable to the volatility of supplies of such fuels for ever more. We are seeing the effects of energy prices every day on the news now. It is having a direct effect on inflation. Energy companies are having to make such large profits in order to prepare for the tailing off of current easy to obtain fossil fuels and develop new sources of supply, which will require significant research to make viable. HS2 and other similar technologies move us away from all that and ultimately allow the country to regain control of the cost of running our transport system. Lowering emissions is the icing on the cake.

@The Yarbles

Unfortunately you are perpetuating the myth that this line will be 75 metres wide.

High speed lines are typically 15 metres wide. You can check this by finding HS1 on Google Earth.

Please see page 13 of this document for a photograph that shows a high speed line and an entire motorway are still far less than 75 metres wide.

Following up from my tweet (AnthonyLeung_)

Basically a study by Steer Davies Gleave (2006) and Janic (2011) show that when HSR is competing with air in EU markets, HSR journeys of around 2 hours have taken at least 50% of the market.

So given many of HS2's journeys will be in this 2 hour range (e.g. London to Manchester/Liverpool/Leeds), one could expect this to occur as well.

Also, Givoni (2006) shows that for routes of 300km or less, the introduction of HSR causes the complete withdrawal/mass reduction of flights. So evidence from Givoni, SDG and Janic allude to the fact that there would be a large modal shift from air to rail. Not sure what the exact emissions reductions figures will be from this shift, but I reckon there'll be a net reduction in emissions.

Also, Givoni (2006) shows that for routes of 300km or less, the introduction of HSR causes the complete withdrawal/mass reduction of flights. So evidence from Givoni, SDG and Janic allude to the fact that there would be a large modal shift from air to rail.

Domestic aviation (including Belfast, Isle of Man, Inverness, Newquay, etc) is 2% of transport emissions. So if you could run high speed rail to Glasgow, Edinburgh, and *all of the above places*, and run the trains off sunshine, the reduction in transport emissions would be 2%. (Assuming the flights were not re-used for international destinations, etc.)

@ShuffleCarrot

Ah the old bury your head in the sand and ignore the problem (because it doesn't fit with your argument) routine!

Sorry to disabuse your viewpoint with some cold hard facts but rail travel has been increasing relentlessly year on year at approx 5 to 6%, even during this period of austerity, public spending cutbacks etc. There IS a looming capacity shortfall whether you like it or not - all of the expert opinion agrees on that fact.

The debate (in expert circles) centres on how to address this widely acknowledged problem. Unsurprisingly we find that some people (like Jerry Marshall of AGHAST) have suddenly and rather miraculously assumed expert status in the complex field of forescasting future passenger traffic demand and management of rail networks.

According to Jerry you can simply wave a magic wand (by lengthening train sets and declassifying carriages) and increase seats by 213% on the WCML, or what is called "sweating the asset". Trouble is his figures are pure fantasy, totally uncosted in any meaningful fashion and rely on statisitcal sleight of hand - RP2 or even RP2+ as a credible solution was eviscerated by simple analysis - see this Now of course it might just be that Jerry Marshall has an interest in this issue because he is a resident of Burton Green, which just happens to be bang right next door to the proposed route of HS2, phase 1 - funny that?

I do not lightly dismiss the negative impact on HS2 on those individuals living in close proximity to the proposed line of route - when HS2 proceeds (nothing is more certain in the relatively uncertain world of politics) and phase 2 comes into operation, the line will actually pass approx 3km from my house (although it wil probably be in deep cutting at the point of closest proximity).

Not sure about others here but when HS2 comes into operation the very last place I'll be travelling to on a High Speed Service out of my Region (NW.England) IS LONDON! I recently travelled from my local station (Wilmslow) to Avignon by train, Wilmslow to London Euston, London St. Pancras to Lille Europe, across the platform and Lille Europe to Avignon, all in the same day. How much easier, and therefore appealing to potential consumers, if my route option was Manchester (South) to Lille Europe (via HS2/HS1), then onward to Avignon. Repeat that travel equation for any number of destinations opening up as the nascent pan-European HSR network expands and rail becomse a credible challenger to short haul air.

The new line may pass through (or rather under) London but that's irrelevant for direct services from provincial UK cities to Europe - you board in your local city and alight at a destination on the near mainland continent, for onward travel. You might as well claim that because an aircraft flies over London on its way to Paris that has some bearing on a passenger's travel choice!

Ultimately this debate comes down to a complex trade off., measuring the benefits accruing to many (UK plc) against the undoubted negative impacts suffered by a tiny group in close proximity to the new route. In such circumstances my vote always goes with the many, even if I'm part of the few!

Our current energy regime is unsustainable. There is a widely held assumption that alternative energy sources like nuclear and renewables can readily substitute for conventional fossil fuels and we can carry on with business as usual.

But is this really the case? Run through the maths to illustrate the point.

In 2010, UK electricity production was 381 TWh - Nuclear 15.6%, Gas 47.3%, Coal 28.4%, Renewables 6.9%, Other 1.8%

Of the 6.9% renewables, 2.6% was wind. In 2010, 10 TWh were generated from wind farms

By 2020, to get to 15% renewables, an additional 47 TWh from wind farms will be required.

A modern 3.0MW wind turbine will typically generate 8760 MWh per year.
Therefore, over the next ten years another 5,369 wind turbines will need to be built - equivalent to 206 Scout Moor wind farms.

If we achieve these targets we would be slightly less reliant on imported gas and coal but not by very much. Currently gas and coal account for 75.7% of electricity generated. With 15% renewables, they would still account for 67.6%.

There are serious questions regarding the future supplies of these fuels—which are being consumed more quickly than they are being found, and are increasingly concentrated in only a few countries.

Renewable energy sources might be able to sustain us in a ‘post carbon’ future, but not in the manner to which we have become accustomed. 'Business as usual' is not sustainable.

One thing that will become a pressing issue, sooner or later, at some point within the next two decades, will be the need for energy conservation. And that will include the speed at which trains travel.

An HS2 train, as proposed, would draw down 12 MW of power from the grid. This would require the average output of 12 wind turbines. HS2 would accommodate 10 trains per hour in each direction in off peak hours, rising to 14 trains per hour during peak periods. So running in peak mode at 360 km/h, 14 trains in each direction would require the average output of 336 wind turbines. The HS2 traction energy modelling carried out at Imperial College shows that operating at 360 km/h consumes 23% more energy than at 300 km/h. So reducing the speed to 300 km/h reduces the required number of wind turbines from 336 to 273.

To put this in perspective, our largest off shore wind farm off Thanet in Kent, consists of 100 wind turbines. Enough to power 240,000 homes or 4 HS2 trains per hour in each direction.

While there is a case for building more railways in preparation for a future without many cars, the emphasis should not be on maximum speed but on minimum energy consumption.

Odd, I would have thought George Monbiots Guardian piece would have been spotted in, er, The Guardian!

http://www.guardian.co.uk/commentisfree/2010/may/17/high-speed-rail-policy-carbon-emissions

I used to go on at length about the lack of green credentials for HS2, such as the fact it relies on taking planes out of the air from places HS2 wouldn't even serve and expects that the bosses at any airport cutting short-haul flights wouldn't just fill them with bigger planes going greater distances.

Now I simply say 'The Green Party are against it'. I find that usually that will suffice!

See http://www.greenparty.org.uk/news/26-02-2011-high-speed-rail-decision.html