High Speed Rail running on conventional rail lines

Japanese High Speed Rail (HSR) Shinkansen runs on dedicated rail lines, but in some areas, exceptional type of Shinkansen called "Mini Shinkansen" runs on conventional ones. Though it isn't a news, as Mini Shinkansen commenced operation in 1997, this fact may have a unique value in today's global HSR construction trend in terms of budget.

By definition, Shinkansen is passenger electric train which runs on dedicated rail lines of standard gauge at speeds of 200 km/h or higher. Current operation of Shinkansen, however, is keeping around 300 km/h on favorably conditioned section. You can see several types of Shinkansen trains in the present service here and here.

Mini Shinkansen is a compromised design of Shinkansen used for mountainous areas where construction of dedicated rail lines is difficult. For example, "Akita Shinkansen", a name of Mini Shinkansen operation which connects Tokyo and city of Akita in the northern part of Japan, runs on dedicated Shinkansen rail lines of 535km from Tokyo to Morioka, while it runs on conventional rail lines of 127km from Morioka to Akita. (For reference, total dedicated rail lines of normal Shinkansen is 2,257km, while exceptional conventional rail lines of Mini Shinkansen is 275km.)

When on dedicated rail lines, Mini Shinkansen runs at speeds of 275km/h, but on conventional rail lines, it runs at speeds of 130km/h. This exceptional Shinkansen has level crossings as usual conventional rail lines (see video below). Also, Mini Shinkansen uses conventional rail station which is concurrently used for ordinary passenger trains.

We can discuss about an idea that HSR having this compromised design would be competitive in today's global race of HSR procurement. HSR in essence is a huge infrastructure investment requiring billions of US dollar. If HSR runs only on dedicated rail lines, capital expenditure of land purchase and construction of railway and station would be high especially in densely populated area such as a center of city. But in case it can run on conventional rail lines, in other words, when using hybrid of conventional ones and dedicated ones, the owner of the project is able to save large portion of capital expenditure. This can be said in particular for the country having wider land where long stretch of dedicated rail lines can be built relatively easily in low populated area. In such a county, they can reduce total travel time of HSR greatly using long stretch of dedicated rail lines, while they can save CAPEX in dense area.

Recently, Japanese government is promoting export of Shinkansen to the countries that have HSR construction plan. For the United States, a consortium of Japanese companies led by Shinkansen operating company Central Japan Railway is trying to sell its full-speck Shinkansen system to the project of Florida HSR. This is good.

However, companies related to Mini Shinkansen such as East Japan Railway may think about possibility of selling this compromised Shinkansen to other HSR projects in US as well as in other countries. They can show business case of cheaper HSR in comparison with full-speck Shinkansen. We know French HSR "TGV" has the same compromised design as Mini Shinkansen. So, French consortium would be a good rival when Japanese companies try to sell this.

Several months ago, East Japan Railway revealed that it developed new Mini Shinkansen train named "E6 series" which can run at speeds of 300km/h on dedicated lines.