Rollingstock to Support Decarbonised Power

Rollingstock to Support Decarbonised Power

New biomass freight wagon to decarbonise power generation

Ricardo was asked by Drax Power to design a new super-sized freight wagon to transport biomass material along the UK rail network to its facility in North Yorkshire.

Since entering into service in 2014, the award-winning wagons have played a central role in transforming the station into one of Europe's largest generators of renewable power.

Originally built as a coal fired power station - Drax now utilises biomass fuel to achieve carbon emissions reductions of over 90%.

A unique wagon design with several patented features

Biomass is a biological plant-based material sourced from forestry and agricultural by-products and is imported into the UK from locations as far away as South America.

Unlike coal, biomass pellets must always be kept dry. This means that the open-top wagons typically used to transport coal on the rail network are unsuitable for carrying the pellets from the UK's ports to the power station.

An initial solution, also developed by Ricardo, saw a retrofit of existing stock to add protective top doors. Even this early work had to overcome some design challenges. For example, freight wagons have no electricity supply to open and close the doors so a system of magnets to trigger and pneumatically operated top doors was proposed. Safety interlocks were included to ensure the doors could not be activated by other magnetic activity during their transit.

However, Drax Power Station's plans to increase the use of biomass in its operations meant a new larger, more efficient wagon design would be needed rather than repurposing the existing fleet. 

Wagon manufacture plant

The UK's largest volume freight wagons

As biomass is less dense than coal, each wagon must carry more load for biomass to remain an economically viable option.

This required a design capable of carrying larger volumes of material yet remaining within the limits of the UK’s loading gauge and operating in compliance with industry regulations.

Biomass Wagon Dimensions
As biomass is less viscous than coal, it does not require the steep tapering at each end of the wagon that helps loads exit through the bottom doors. This meant extra volume could be gained by 'squaring off' each end.  A new product flow control system was also developed to channel the flow of material and reduce spillage.

Further capacity was gained by relocating the wagon's pipework, structural supports and control equipment.

Drax biomass wagon in service
At 18.9m long, the 'super-sized' wagons offered a capacity of 116 cubic metres - allowing for a biomass load weighing 70 tonnes - which is almost 30% cent bigger than any other freight wagon on the UK network.

Today, Drax Power Station receives more than 7 million tonnes of biomass a year, almost all using its fleet of 225 wagons. Around 17 trains of 25 wagons arrive each day. Such quantities enable the station to provide 15% of the country's renewable power.

In 2019 biomass accounted for 6% of Great Britain’s electricity generation.

If you have rollingstock to repurpose or require design analysis and certification expertise for your next project then get in touch with our team.

Design and analysis

Design and analysis

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