Energy crops take a roasting

May 21, 2008

A process used to roast coffee beans could give Britain's biomass a power boost, increasing the energy content of some of the UK’s leading energy crops by up to 20 per cent.

The study, carried out by engineers from the University of Leeds, examined the combustion behaviour of crops grown specifically for energy creation when put through a mild thermal process called ‘torrefaction’ – more usually associated with coffee production.

Torrefaction is increasingly seen as a desirable treatment for biomass because it creates a solid product which is easier to store, transport and mill than raw biomass.

The study examined the energy crops willow, canary grass and agricultural residue wheat straw to see what happened when they went through the torrefaction process and how they behaved at a range of temperatures when they were heated to create an energy-enhanced fuel.

Results showed that the treated materials needed less time and energy to heat to burning point, and also that they offered increased energy yields upon burning.

Willow emerged as having the most favourable properties, in that it retained more of its mass in the torrefaction process and also performed best in terms of its energy yield. As an example, willow was shown to have an 86 per cent energy yield, compared with 77 per cent for wheat straw and 78 per cent for reed canary grass.

“Raw biomass takes up a lot of space and has a low energy density which makes it costly – environmentally and economically – to transport. Plus you need more of it than say, coal, to produce energy efficiently,” says Professor Jenny Jones who worked on this study with PhD student Toby Bridgeman.

“Torrefaction is not currently used in the UK in either the agricultural or the energy sectors,” says Bridgeman. “But our paper shows that it has a lot of benefits, besides those to do with fuel handling, so we feel it’s definitely something we’d like to explore further.”

Source: University of Leeds

Explore further: Bribery 'hits 1.6 billion people a year'

add to favorites email to friend print save as pdf

Related Stories

Toward mitochondrial plant cell factories

Jan 15, 2015

In work published in Scientific Reports, a group of researchers led by Jo-Ann Chuah and Keiji Numata of the RIKEN Center for Sustainable Resource Science have devised a new strategy for selectively delive ...

Recommended for you

Bribery 'hits 1.6 billion people a year'

Feb 27, 2015

A total of 1.6 billion people worldwide – nearly a quarter of the global population – are forced to pay bribes to gain access to everyday public services, according to a new book by academics at the Universities of Birmingham ...

How music listening programmes can be easily fooled

Feb 26, 2015

For well over two decades, researchers have sought to build music listening software that can address the deluge of music growing faster than our Spotify-spoilt appetites. From software that can tell you ...

Nature journal to begin offering double-blind peer review

Feb 23, 2015

Well known and respected journal, Nature, will begin next month offering researchers who submit their work for peer review, the option of having it done via the double-blind method—whereby both submitters and re ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.