Biofuels apply to solid, liquid or gaseous fuel produced from biological materials (biomass). The biomass constitutes the feedstock destined for conversion into biofuels. Biofuel is a renewable energy resource, and considered as a viable alternative to the non-renewable fossil fuel (i.e, coal, crude oil & natural gas).
The main reasons for promoting use of biofuels include:
i) The need for a renewable substitute for the non-renewable fossil fuel.
ii) The low-carbon biofuels emit less greenhouse gases (e.g. CO2 ) compared to high-carbon fossil fuels.
iii) The need to promote the agricultural sector.
However, recent studies have shown that the continued surge in biofuels production diverts food from the hungry; contributes to destruction of forestlands; and also contributes to increase in emission of greenhouse gases by destroying the carbon sinks (forests).
What are Biofuels?
Based on feedstocks, biofuels can be broadly classified into two:
1) Biofuels derived from food sources. These biofuels utilize food crops and other food sources as feedstocks. They include:
a) Bioethanol is a biofuel that is traditionally produced from the fermentation of food crops such as corn, sugar beet and sugar cane. Bioethanol can be blended with petrol for use in petrol-engine vehicles. Biobutanol can easily be added to conventional petrol due to low vapour pressure and can be blended at high concentrations than bioethanol. However, biobutanol is still in research and development.
Bioethanol, when blended with petrol derived from fossil fuel, enhances octane rating of the latter. Octane number is a measure of the burning efficiency of a fuel. The higher the octane number the slower the fuel burns. Bioethanol is, therefore, a cost effective octane-enhancer.
Most countries have policies which make it an obligation that a certain percentage of fossil fuels should be made up of biofuels. The Renewable Transport Fuels Obligation (RT FO) in UK requires all fuels sold in UK to be blended with 5% biofuels by 2010. The US also has similar policy. The Nigerian government has set the target for 10% ethanol content in fuel by 2010.
b) Biodiesel is a biofuel produced from various feedstocks such as vegetable oils (derived from oil palm, rapeseed and soya beans), animal fats (tallow) etc. They are used to run diesel –engine vehicles and machines.
2) Biofuels derived from non-edible feedstocks. They are generally considered as second generation biofuels.
a) Bioethanol: The following non-food plants can be used as feedstocks for producing bioethanol.
i) Bagasse: It is a sugarcane waste.
ii) Switchgrass: It is native to the US and known for its hardiness and rapid growth.
iii) Miscanthus: It is also called elephant grass. It is a genus of about 15 species of perennial grasses native to substropical and tropical regions of Africa and southern Asia.
b) Biodiesel: The non-food sources for biodiesel include:
i) Jathropha: It is non-edible evergreen shrub found in Asia, Africa and the West Indies.
ii) Algae: They are primitive plants, usually aquatic, capable of manufacturing their own food by photosynthesis. They are still being investigated as a possible feedstock for biodiesel.
Biofuels: Friend or Foe?
Biofuels seem to be a viable alternative to traditional fossil fuels, but the problem seems to lie in ensuring that only non-food sources are used for biofuels production. Food crops are increasingly becoming economically attractive as feedstocks for biofuels production. A World Bank working paper suggests that biofuels are responsible for pushing food prices up by 75 percent, causing riots in Egypt, Malaysia and other poor countries.
The current biofuels bandwagon, promoted by agriculture interests and based on food crops, has no respect for biodiversity, the health of farming communities, conservation of forestlands, and the need for ample and affordable food supplies. It is therefore far from being an element of a sustainable energy system. The world faces an impending ecological disaster unless we redirect biofuels technologies to development and production of second generation biofuels, which use waste materials and non-food crops that can be grown on marginal land as feedstocks.
Ensuring a Sustainable Energy System
The potential impacts associated with the current biofuels production include nitrogen runoff into waterways, the decline in fresh water supplies and reduced air quality. Others are rising food prices and clearing of forestlands to cultivate feedstocks for biofuels.
Hence, there is a need to ensure that environmental considerations play a priority role, to enhance sustainable production of biofuels. Even though science- based benchmarks and indicators for biofuels production and use are in the process of development, all the stakeholders agree that the industry should operate sustainably and responsibly.
The sustainability criteria currently being proposed include but not limited to the following:
i) The cultivation of biofuels feedstocks shall not compete directly with food production.
ii) Biofuels production shall respect biodiversity and the health & well-being of farming communities.
iii) Local people shall be fairly and equitably compensated for the land acquired for cultivation of biofuels feedstocks.
iv) Slave labour and child labour shall be avoided.
v) Forests shall not be cleared for the purpose of cultivating biofuels feedstocks.
vi) Only marginal, degraded, or previously cleared land shall be used for growing biofuels.
vii) Biofuels production shall address all problems bordering on land, air and water pollution.
Biofuels Production in Nigeria
Nigeria, eager to jump on the bandwagon for biofuels, has a policy to meet 10 percent bioethanol content in fuel by 2010. In pursuance of this policy, the immediate past regime earmarked thousands of hectares of virgin land for cultivation of cassava to supply feedstocks for production of ethand. The cassava initiative, as it was called, did not, however, succeed.
In a new development, Global Biofuels Limited has embarked on a project which will use about 10,000 hectares of virgin land (forests and grasslands) covering seven states (Osun, Oyo, Kwara, Ondo, Ekiti, Niger and Kogi) in Nigeria, to cultivate sweet sorghum feedstock for ethanol fuel production.
Global Biofuels Limited plans to set up seven plants each valued at over 3 billion US dollars(345 billion naira ) in the seven states, to produce about 1 million liters of ethanol per plant on a daily basis. The company cites high oil prices and environmental concerns to justify its huge investment in the sorghum to ethanol fuel production project in Nigeria.
Without mincing words, biofuels production in Nigeria is a misplaced priority. It negates self -sufficiency in food production, which is one of the 7 point agenda of the current administration. The sorghum feestock for the biofuels plants will compete with production of food crops, thereby exacerbating hunger in the nation.
The biofuels production in Nigeria utilizing food crops, or cultivated on high-value land and cleared forest will impact negatively on environmental quality. Nigeria, despite unrelented afforestation programmes, is yet to achieve the 25% forest cover stipulated by international standards. In this regard, we cannot afford to lose our fragile forests and other high-value land to biofuels at the expense of food crops production. Bioethanol production is also one of the most vilified chemical processes on account of its high level of pollution. This will mean taking pollution to rural areas at this time when our environmental regulatory bodies have lost control over urban pollution problem.
Biofuels had been touted as a low – carbon fuel that could power vehicles and improve the well – being and socio economic status of the world’s rural people. It is now accepted worldwide that the forests, fields, and peat bogs cleared to make room for biofuel crops may cause more carbon to be released into the atmosphere than they would save from vehicles not burning high-carbon fossil fuels.
The biggest challenge to biofuels sustainability is ensuring that food crops are not used as feedstocks. Also, the sustainability criteria should make only marginal, degraded, or previously cleared land acceptable for growing biofuel feedstocks. There is a need for cautious approach on biofuels production and use, to ensure sustainable development and ample and affordable food supplies.