Electrification: Putting the Spark Back into the Railways

Kevin McNealey
In the rail sector, the drive to reduce carbon emissions is positioning electrification as part of a wider environmental solution. The initial high capital investment costs have historically been the main stumbling block. Life cycle costs, however, more than offset the initial installation costs and ongoing maintenance.

Only 40% of Britain's rail network is electrified - a much lower proportion than other comparable European systems. The railway industry claims that further electrification would improve reliability and punctuality, and bring environmental benefits.

Electrification comes in many forms:

  • Light-weight overhead contact system, as used on Light Rapid Transit schemes
  • more robust weight system on traditional heavy rail schemes
  • 3rd or 4th rail pick-ups on metros, undergrounds and some low speed high traffic density networks

The initial high capital investment costs have historically been the main stumbling block. Another often overlooked issue is the increased cost of maintaining the new electrification equipment.

Low traffic volume routes are not usually electrified as they suffer from disproportionatly higher investment and maintenance costs when compared to the projected rate of return. This is apparent in North and South America, Asia and Europe (especially the UK and Ireland) where many long-distance lines are not electrified due to relatively low frequency of trains.

The situation is now changing worldwide, driven by the need to reduce carbon emissions. This positions electrification as part of a wider environmental solution. It also underpins high speed rail as a viable alternative to air transportation on journeys over 300 to 400 kilometres. See the Atkins High Speed Line Study for more details.

Advantages include lower running costs, faster acceleration, higher speeds and less noise pollution than non-electrified railways. The debate has been widened, and issues to be considered when reviewing the justification for electrification schemes now include:

  • Capital cost of electrification
  • Maintenance cost of the fixed equipment
  • Availability of suitable rolling stock
  • Maintenance, fuelling and fuel costs for diesel and electric trains, including the effects of regenerative braking
  • Emissions produced by diesel and electric trains
  • Weight of trains
  • Comparative reliability of diesel and electric trains
  • Availability of spare power capacity in the feeder network;
  • Interfaces with other major projects, eg. signalling.

Electrification brings both environmental and operational benefits. Tighter emission regulations and the worldwide push to reduce carbon emissions are making diesel engines heavier and more complex. Electric trains emit 20-30% less CO2 than diesels. Electrification brings improved energy efficiency in rail operations. The operating costs of electric traction compared to diesel is about 35% less.

Life cycle costs, over the 40+ years lifespan of a typical electrification scheme, more than offset the initial installation costs and ongoing maintenance. Given sufficient traffic, electric trains produce fewer carbon emissions than diesel trains, especially in countries where electricity comes primarily from non-fossil sources.

In the UK new advice has been issued via the BCIS and British Standards Institute (BSI) on the calculation of life cycle costs for construction. The aim is to promote an industry-accepted methodology to facilitate more accurate and consistent application of life cycle cost estimation. Faithful+Gould was a primary contributor to this work.

Faithful+Gould continues to play a principal role in this reinvigorated market. We have been involved in the estimating activities for several major projects, including the Edinburgh to Glasgow Improvement Programme, Dublin Metro West and Thameslink.

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