South Africa has not yet embraced bioenergy, which comprises biofuels, biogas and bioelectricity, in earnest, says Stellenbosch University senior chair of energy research in biofuels Professor Emile van Zyl.

“Biogas produced from anaerobic digesters using sewage, manure or other readily degradable organic residue is used on a small scale on farms or village-like settlements as an energy source, but it hasn’t really taken off.

“Several companies and start-ups had considered burning biomass for electricity generation purposes; however, on its own this is not a very sensible practice,” he states.

Van Zyl suggests that using a combination of excess plant residues and residue streams from biobased industries, such as sugar and paper and biofuels plants can be more effectively used for the cogeneration of electricity than simply burning biomass.

He notes that this makes more economical sense, as organic materials, such as plant residue, have a higher value when converted into biofuels or other commodity products, thus replacing fuels at about ten times the monetary value than the conversion from coal to electricity.

Biofuels Market
Van Zyl says the recent announcement in the Government Gazette by the Department of Energy regarding the mandatory blending of biofuels with petrol and diesel could lead to the creation of a vibrant biofuels market, which, in turn, could kick-start a bioenergy industry in South Africa.

In addition to creating a biofuels market, it is important that South Africa’s fuel standards be upgraded in the near future as this creates incentives for the blending of biofuels with petrol and diesel during production to meet fuel standards.

Further, Van Zyl recommends that less intervention from government in terms of who may produce biofuels and from which feedstocks, the simplification of the licensing of biofuels production and the encouragement of more start-ups in this new field, might help expedite the development of bioenergy and biofuels in South Africa.

He hopes this will have a spillover effect into neighbouring countries, some of which have greater potential for biofuel feedstock production.

Van Zyl reiterates that bioenergy will not, in the long run, be a viable option for grid electricity generation, as it does not make sense to compete with coal by using valuable biomass.

“Why use highly evolved molecules that are produced by nature as part of plant structures and simply burn them through combustion to generate electricity with a low value?

“I would rather promote the use of biomass as a replacement for fossil fuel in the future, thereby developing a new green chemistry industry and economy and replacing crude oil as the basis for the production of liquid fuels and other higher-value chemicals,” he comments.

Further, he says bioenergy production can be integrated into agriculture and forestry if it is approached in a sustainable way and best practices are followed. He says this can be synergised with food production and actually guarantee food security.

An integrated approach, where bioenergy is produced from nonfood residue and crops, creating alternative markets for farmers, is integral to food security.

Bioenergy could also create jobs through the expansion of the agricultural and forestry sectors.

However, Van Zyl notes that one of the shortfalls of bioenergy is its complexity.

“It is not a simple standalone technology, such as wind turbines and solar energy units. Because of the complexity of bioenergy and its integration into agriculture and forestry, coupled with fears around food security, people are hesitant to get involved and politicians prefer rather to play it safe and conservative in this debate,” he says.

He also reveals that South Africa does not have a skills pool large enough to implement bioenergy to its fullest, using advanced technologies.

To deal with this problem, Stellenbosch University runs programmes through the senior chair of energy research: biofuels, which offers postgraduate training towards Masters and Doctoral degrees in advanced biofuels or bioenergy technologies.

Another postgraduate programme in renewable and sustainable energy studies includes postgraduate courses in different renewable energy areas, including bioenergy.

The programme is run by the Centre for Renewable and Sustainable Energy studies, under the leadership of Professor Wicus van Niekerk.

Stellenbosch University also focuses on new and advanced second-generation technologies for the conversion of nonfood residues and crops for bioenergy production.

Van Zyl says these technologies should allow for the integration of bioenergy production into existing biobased industries, such as the pulp and paper, as well as sugar industries.

In turn, this will ensure the complete use of plant material and the development of products and energies from these materials.

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