Power Point: Sustainable biomass and the future of energy
27 October 2015 |
It’s a drizzly morning in Yorkshire and I’m gazing up at a series of huge overhead cables. The electricity passing through them, my guide tells me, is enough to power any major UK city outside of London. But this does not even represent Drax power station’s full output.
The entire plant, which operates within a 16-kilometre working perimeter, produces between 7 and 8 per cent of the country’s power. While all of this used to be generated by burning coal, the facility is undergoing a transformation to integrate sustainable biomass, which consists of materials including sawmill residues, pulpwood and low-value parts of harvested trees that cannot be used for other commercial purposes.
“We believe there is a very strong case for biomass,” says Drax Group chief executive Dorothy Thompson, and the statistics certainly seem to back her up. Two of Drax’s six generating units have been converted so far, with a third currently being modified to burn “a high percentage of biomass with some coal”. When all three units are converted the station will save 12 million tonnes of carbon per year.
Although more carbon dioxide is released during the production and transportation of biomass, overall it generates 86 per cent less carbon emissions than coal because the carbon released during combustion is that which the trees absorbed during their growth.
The transformation could also save the UK money as it seeks to move to renewable energy. By converting existing infrastructure, Drax’s project avoids some of the costs of other projects like the construction of offshore wind farms. It is also a constant energy source, not requiring a backup plan for when there is no sun or wind.
Another reason for a move away from coal is the decline of the UK’s coal industry. While the percentage of coal Drax sourced from the UK was in decline, the amount of biomass it
sourced from UK firms increased from 36,000 tonnes in 2013 to 113,000 tonnes in 2014.
“Half of our coal used to come from UK coal producers,” Thompson explains. “Slowly but surely the UK industry has been closing down. One of the reasons is that on the international market coal has become very, very cheap.”
Drax anticipated this decline and saw the situation as an opportunity to move to renewable energy through biomass. It committed to the project and secured the support of the government for the conversion of the three units.
“Coal will be dead by 2020,” says Drax Group operations director Peter Emery. “We could see that coming, so biomass gave us a chance to play a part in that process [by moving to renewable energy]. We converted the unit without any loss of output. We have done a lot of work on the supply chain to make it reliable. We are very pleased.”
Part of that supply chain is Enviva Biomass, a US-based business that expects to produce 2.2 million tonnes of the material in 2015, the majority of which will go to Drax. Projects like the one in Yorkshire are helping to fuel a burgeoning industry.
“I think what has driven the growth of the industry over the last few years has been the replacement of coal in power generation, primarily because of the greenhouse gas benefits of doing that,” says Enviva’s vice president of communications Kent Jenkins, who explains that the market looked very different when it previously primarily produced biomass for home heating. “Before the industrial biomass market what we have seen was a much smaller and more fragmented marketplace. Until four or five years ago the primary application for wood biomass was home heating. It tended to be here in the States and elsewhere.
“The producers tended to be fairly small and they tended to be regional. The arrival of the market to supply electric power generation in effect created an industrial market for wood pellets that is very different from the home heating market.”
According to figures from independent forest products and bioenergy consultancy Hawkins Wright, wood pellets have a global market value of more than $4billion a year, with production having doubled to more than 20 million tonnes between 2007 and 2013.
Meanwhile, European Union import volumes increased from 6.03 million tonnes of pellets in 2013 to 6.48 million tonnes in 2014. Imports grew by a further 7 per cent year-on-year in the first half of 2015 and, although there are uncertainties surrounding policy in the UK and EU, it is anticipated that demand could double before 2020.
With more forest area available in the US than in the UK and Europe, the established forestry industry is able to produce enough biomass to meet demand while maintaining sustainability. There are twice as many trees in the south of the country now than there were in 1953, Jenkins says. He is also very positive about the future in terms of biomass demand.
“The next one that we will see is the use of wood pellets for large-scale industrial and commercial heating,” he explains, acknowledging the energy industry’s role in the sector’s growth. “It is a premium market and it exists at the scale it exists at in significant part because of the electric utility market and the market to replace coal fuel for electric power generation.”
This is a sentiment echoed by Emery, who says that the biomass industry and its supply chain are still in their “very early stages”. This renewable source of energy could have a lot more to offer in future, he explains, not just in terms of expansion into new areas, but with the development of more efficient processes at facilities like Drax.
“This is in its infancy,” he says. “In 20 more years we will be far more efficient at this. We will be able to use a lot of trimmings and filings that we cannot use today. This is the first stage of how we will use biomass as energy.”
With Drax expecting to produce 4 per cent of the UK’s power from biomass in 2016, the government, keen for people to convert their home boilers to run on the material and industrial and commercial heating set to join the movement, the future could be very bright for the biomass industry.