From plant to port: The journey of a compressed wood pellet

Trains, trucks and transatlantic ships – each play a crucial step in moving biomass from the working forests of southeastern USA to a power plant north of London helping to deliver a cleaner energy future for our planet.

Consider the wood pellet. Drax Power Station in Yorkshire, England uses millions of tons every year to generate electricity. A significant proportion of those pellets are produced right here in the US at two facilities – one in Bastrop, Louisiana and one in Gloster, Mississippi.

But before they can be used to generate electricity, they must be transported safely and efficiently across the Atlantic. And before that can happen, the pellets must first reach Drax Biomass’ port facility near Baton Rouge, Louisiana.

That initial journey requires both trucks and trains.

Drax Biomas Truck

The road trip

The Amite BioEnergy pellet plant in Gloster lies roughly 60 miles from Baton Rouge. Because rail infrastructure was incomplete when the plant was first built, it was decided that trucks were the best option for moving the pellets from plant to port.

“Each truck can carry 25 tons of pellets per load, and the journey takes around 90 minutes – accounting for the trucks slowing down when they pass through urban areas. It means that one driver can do three trips on any given day,” says Lloyd Wedblad, Vice President of Logistics and Optimization at Drax Biomass.

Bastrop presented a slightly more challenging scenario, as the team needed to find a quick and economical way to transport pellets 221 miles from Morehouse BioEnergy to the port.

Pellet trains in the station

Riding the railway

A solution was found in the region’s robust rail infrastructure, which includes the Arkansas Louisiana Mississippi (ALM) railroad. Opened in 1908, the ALM line runs from the City of Monroe, Louisiana to Bastrop, just south of the Arkansas state line.

The trains leaving Morehouse BioEnergy use closed-top grain cars rather than open-top coal cars to protect pellets from the elements. Unlike coal, if wood pellets get wet, they quickly deteriorate and cannot be used as fuel at the power plant.

“The cars are designed to each carry 286,000 pounds. But because of local weight limits on bridges and sections of track along the route, we’re limited to hauling 263,000 pounds per car. That’s still a lot of pellets,” says Wedblad.

Once the train arrives at the port, it takes around 24 hours to unload before making the 20-hour return journey back to Bastrop. One train departs roughly every three days, so over 110 trains are required each year to move this facility’s pellets to the port.

Morehouse BioEnergy is currently served by 45 car-length trains, but this will soon change – in a big way. A new railyard planned for the port will allow the team to begin shipping pellets on 80-car length ‘unit trains’ – each nearly a mile long and capable of carrying almost double the volume of current trains. Unit trains will deliver major fuel and cost savings to Morehouse BioEnergy and improve Drax Biomass’s overall supply chain efficiency.

Vessel Loading at Baton Rouge

Preparing for the overseas journey

The final stage of the pellets’ journey begins along the Mississippi River at the Port of Greater Baton Rouge. As the pellet-laden trucks arrive from Amite, they drive into customized bays where they unload their cargo onto a conveyor belt in roughly six minutes before returning to the Gloster facility.

But the trains prove to be a more elaborate challenge – one that will get trickier still as the business transitions to 80-car unit trains. When a train arrives at the port, it is divided into several shorter car-lengths before each is routed into an unloading facility.

The cars deposit their cargo onto a separate conveyer belt, which – like the belt under the truck bays – moves the pellets into one of the port’s two 40,000-metric ton storage domes.

Once the domes contain enough volume, a cargo vessel arrives for the transatlantic journey to the UK. Yet another conveyor belt moves the pellets from the domes to the dockside shiploader, which loads each cargo hold until the vessel is ready to sail.

drax-ship-at-port

A sustainable supply chain

Not only is this journey from plant to port one that is growing more and more efficient, it’s a sustainable one, too. The emissions associated with each stage of the journey is tracked to ensure the Drax Group supply chain is as low-carbon as possible.

Even with all supply chain emissions considered, the power generated all the way in Drax Power Station in the UK has a carbon emissions profile that is 80% lower than coal. Of all the journeys involved in powering the UK’s biggest single site electricity generator, perhaps the most impressive is how this transition from coal to renewable compressed wood pellets has been made.