High Speed Rail and India's Carbon Future

The news has been full of the India-Japan announcement of the first high speed rail (HSR) project in India.  It will be built to run between Mumbai and Ahmedabad (Wiki information here).  While Japan has offered extremely low cost financing, the overall project cost (of the order of 10^12 Indian rupees) has raised a lot of concern about the viability of the project, whether it is the right investment to make, etc., etc.  You can do a news search and look that up.

There is one aspect which I haven't seen discussed very much, and that India's future transportation needs weighed against need to curb greenhouse gas emissions.

At this point, I pause to say, I wish I had command of a thousand mes, to do some serious research in this and so many other areas.  Instead what you get is from a couple of hours of Google search research, with very little validation on my part that the ideas and numbers make sense. Since major economic and political interests are involved, validation is certainly required.

It seems that a good way to think about the demand for transportation is "GDP-transport elasticity". E.g., 

The Indian economy has a GDP-transport elasticity of 1.25 (For every one per cent growth in GDP, transport sector has to grow by 1.25 per cent). 

For comparison, Europe:

• For passenger transport, the GDP elasticity is equal to 0.65 on average for the period 2005 to 2030.

• For freight transport, the GDP elasticity of activity is projected to decrease gradually, first down to 0.92 in 2005-2010, and then further down to 0.72 between 2010 and 2030. 

It would make sense then, to seek "GDP-transport elasticity" for passenger and freight traffic and for rail, road, air transport separately.   Since HSR is passenger-centric, I'll seek numbers for passenger traffic only, to limit the length of this post.

This 2013 Indian Planning Commission Report has some figures and estimates, below the fold:

India: Passenger Traffic - Rail and Road - 1950-2012

India - Passenger Traffic Elasticities with respect to GDP

Suraj on the BRF forum makes a further point - some excerpts below:

When you have an economic system where access to transportation ranges between a tiresome hassle and a massive hassle, a lot of potential journeys are forsaken......When you have an extremely supply constrained economy, general calculations of demand indexed to income go out of the window as latent demand is unlocked due to the convenience. Each bullet train has ~10x the seats of a flight, substantially greater comfort, comparable or lower cost and convenience of point to point city center access.

This phenomenon has also been seen in Delhi Metro, where demand initially lagged projections as the first few corridors were not optimal to unlock the potential for more traffic, but as the latter parts of Phase 3 came online, suddenly they find that live demand exceeds their earlier projections, and now they're rushing to get Phase 4 done to mitigate the crush density demand. New Delhi therefore goes from having 0 km metro in 2002, to having the world's third longest network in 2023 - longer even than NYC, London etc. It's the same for intra-city car population in India or worse, major Chinese cities. As well as the Chinese HSRs that run quite packed.

The takeaway is that if India fulfills its dreams of economic growth (e.g., even the modest average of  a 7% growth rate and a quadrupling of the GDP in 20 years), the demand for passenger  transportation will greatly increase.  If the current trendline holds, road traffic will increase 8-fold, and that is a CO2 emissions and air-pollution disaster in the works.

Carbon intensity:

HSR is particularly efficient.  E.g., this study from UK, from around 2010:

Air, Road, HSR CO2 per passenger kilometer at various load factors

and they write (emphasis added):

This indicates that, at any given load factor, high speed rail already outperforms both car and short haul jet aviation even without electricity being decarbonised.

They make this illustrative calculation:

Carbon intensity of passenger transport alternatives

Just fyi, about Shinkansen  - which is what India's first project will have, this American paper from 2010 says:

The intensity of a trainset is expressed in kWh/seat-km. Thompson compiled a number of values of energy intensity of Shinkansen from Japan Rail publications.  The first Shinkansen (zero series) required 0.072 kWh/seat-km with a top speed of 220 km/hr, while the most recent Nozomi 700N requires 0.037 kWh/seat-km at that speed and 0.049 kWh/seat-km at 270 km/hr. Thus the energy intensity of the Shinkansen has been falling, to a point where the recent Nozomi 700N uses about 50% as much energy at a higher speed than the original Shinkansen, and 32% less energy at 22% higher speed.

and, optimistically:

Given the technical progress of all HSR, it is likely the decline in intensity exhibited by the Shinkansen will be continued.

One way of looking at these numbers is that for a given amount of CO2 emissions, India can grow passenger traffic three times as much by HSR than by road transport.

HSR can also divert traffic from short-haul air routes, with enormous savings in CO2 emissions. 
Per Wiki, about Taiwan HSR:

The high-speed trains have successfully out-competed planes: by August 2008, half of the air routes between Taipei and the country's western cities had been discontinued, including all connections between cities with THSR stations except for a single daily connection between Taipei and Kaohsiung. Total domestic air traffic was expected to be halved from 2006 to 2008, and actually fell from 8.6 to 4.9 million. In June 2012, officials announced the discontinuation of the last remaining commercial flight between Taipei and Kaohsiung.

Just from a carbon footprint perspective, High Speed Rail is a strategic imperative for India.   The world, to the extent it is worried about climate change, ought to be rooting for the Indian high speed rail projects to be wildly successful.

PS: What about all-electric cars?   It seems that the best, in 2012, is about 0.100 kWh/km. With one person in the car, this is still twice the intensity of the Shinkansen Nozomi 700N running at 270 km/hour.

Electric car energy efficiency 2012