Desert 'carbon farming' to curb CO2

1 August 2013

Share

close panel

Share page

Copy link

About sharing

By Matt McGrath

Environment reporter, BBC News

Scientists state that planting great deals of jatropha trees in could be an effective way of curbing emissions of CO2.

Dubbed "carbon farming", researchers say the concept is economically competitive with modern carbon capture and storage jobs.

But critics say the concept could be have unforeseen, unfavorable impacts including increasing food costs.

The research study has been published, external in the journal Earth System Dynamics.

Seeds of change

Jatropha curcas is a plant that came from Central America and is effectively adapted to extreme conditions including exceptionally dry deserts.

It is currently grown as a biofuel, external in some parts of the world because its seeds can produce oil.

In this research study, German researchers showed that one hectare of jatropha could capture approximately 25 tonnes of co2 from the atmosphere every year. The researchers based their price quotes on trees currently growing in trial plots in Egypt and in the Negev desert.

"The outcomes are overwhelming," stated Prof Klaus Becker, from the University of Hohenheim in Stuttgart.

"There was good development, an excellent response from these plants. I feel there will be no issue attempting it on a much bigger scale, for example 10 thousand hectares in the start," he stated.

According to the scientists a plantation that would cover three percent of the Arabian desert would soak up all the CO2 produced by cars and trucks in Germany over a 20 year duration.

The researchers say that a critical component of the plan would be the accessibility of desalination facilities. This indicates that at first, any plantations would be restricted to seaside locations.

They are hoping to establish larger trials in desert areas of Oman or Qatar. Prof Becker says that unlike other schemes that simply balance out the carbon that individuals produce, the planting of jatropha could be a good, short-term option to climate modification.

"I think it is a great concept since we are truly extracting co2 from the atmosphere - and it is completely various in between drawing out and preventing."

According to the researcher's computations the expenses of suppressing carbon dioxide via the planting of trees would be between 42 and 63 euros per tonne. This makes it competitive with other strategies, such as the more high tech carbon capture and storage, external (CCS).

A variety of countries are presently trialling this technology, external however it has yet to be released commercially.

Growing jatropha not only soaks up CO2 but has other benefits. The plants would assist to make desert areas more habitable, and the plant's seeds can be gathered for biofuel say the researchers, offering an economic return.

"Jatropha is perfect to be developed into biokerosene - it is even better than biodiesel," said Prof Becker.

But other experts in this area are not persuaded. They indicate the truth that in 2007 and 2008 great deals of jatropha trees were planted for biofuel, especially in Africa. But a number of these endeavors ended in tears,, external as the plants were not extremely successful in coping with dry conditions.

Lucy Hurn is the biofuels project supervisor for the charity, Actionaid. She states that while jatropha was once viewed as the excellent, green hope the reality was really different.

"When jatropha was presented it was seen as a miracle crop, it would grow on scrubland or limited land," she stated.

"But there are frequently individuals who need marginal land to graze their animals, they are getting food from that area - we would not class the land as minimal."

She mentioned that jatropha is extremely toxic and can contaminate the land it is grown on, even in a desert. And she also had issues about the fairness of the idea.

"It is still somebody else's land. Why go in and grow these huge plantations to deal with an issue these individuals didn't actually trigger?"

Follow Matt on Twitter, external.

More on this story

'Carpets of seaweed' grown for fuel. Video, 00:03:05'Carpets of seaweed' grown for fuel

1 July 2013

Biofuels are 'unreasonable method'

Published

15 April 2013

Related web links

Universität Hohenheim

European Geosciences Union

The BBC is not accountable for the content of external sites.