Using waste oil to produce biodiesel has been proposed as an alternative to burning greenhouse gas-emitting fossil fuels in several world economies. To assess the current research and perspectives on this production route going forward, a new study published in the journal Sustainability has focused on waste oil biodiesel production in South Africa, a country that relies heavily on imported energy resources.
Study: Biodiesel Production from Waste Oils: A South African Outlook. Image Credit: Scharfsinn/Shutterstock.com
Energy Security in South Africa
South Africa’s oil crude reserves are 0.95 thousand barrels per day as of September 2021, according to the World Data Atlas. However, in December 2020, daily crude oil production was 0.55 million barrels per day, with daily petroleum consumption around 0.49 million barrels per day. Currently, 64% of South Africa’s daily oil consumption comes from imports.
This makes the nation’s economy vulnerable to fluctuating global oil prices, and as a result, South Africa’s energy security is affected. Rapid industrialization and growing urbanization are driving increasing demand for energy and dwindling natural resources and concerns over the effect of burning fossil fuels on climate change and the environment have led to a growing sense of urgency to switch to sustainable, environmentally friendly alternative energy and fuel sources.
Waste Oil: A Route to Producing Sustainable Biofuels
The production of biofuel has grown over the past decade to satisfy the needs of a more environmentally conscious transport industry and address the energy gap caused by the phasing out of fossil fuels. In 2018, global biofuel production reached 154 billion liters, with output forecast to increase by up to 25% by 2024. Major producers of biofuel include Brazil, Argentina, Germany, Indonesia, and the United States. Currently, biofuels account for only 2.5% of South Africa’s liquid fuel market.
Biofuel is produced from sustainable biomass, which overcomes the issue with depletion of fossil fuel resources and reduces the net carbon emissions of the energy and transport sectors. However, a main issue with using food crops to create biofuel, such as bioethanol and biodiesel, is the issue with food security in vulnerable societies. Land given over to biofuel production, whilst commercially viable, leads to less land for vital food production.
An alternative to producing biofuel from crops is to produce it from waste oil such as cooking oil. As one of the major factors that influence the viability of large-scale commercial use of biofuels is cost, despite its advantage for reducing carbon emissions, valorizing waste streams provides the potential for cheaper production. Over 70% of the cost of biofuel manufacture is associated with feedstock. Biodiesel is commonly produced from vegetable oil, but the cost of using this kind of feedstock means that biodiesel is, on average, 1.5 times higher than conventional diesel. Waste cooking oil, on the other hand, costs about 2-3 times less than virgin vegetable oil, which can considerably reduce production costs for biofuel.
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By utilizing waste oil streams, domestic production of biofuel can be significantly increased, improving the energy security of countries such as South Africa and developing nations that rely heavily on imports to satisfy their domestic fuel and energy demands. Additionally, making use of waste oil satisfies the aims of the circular economy by providing an effective waste management strategy. Moreover, in South Africa, which recently suffered a major drought, vegetable oil is needed to feed the nation’s population.
The influence of biofuel production on each country’s economy will be determined by the commitment of that nation’s stakeholders to achieve a transition from fossil fuels to renewable energy and fuel sources.
The study in Sustainability provides an overview of current research and its implications for the future production of biodiesel for fuel and energy needs in South Africa. The production process, catalysis, and other important economic and technical aspects of biofuels are discussed in the research. There is a special focus on waste cooking oil.
Despite several international agreements and regulations concerning waste oil management, there is very little pressure on residential waste generation by South African legislators. As a result of this lack of legislation, a significant amount of waste cooking oil is dumped by South Africans, who are not knowledgeable about the negative environmental impacts of waste oil or its recycling. However, South Africa has introduced several regulations in recent years that cover biofuel production, such as 2007’s National Biofuels Industrial Strategy and 2008’s National Energy Act.
The study has identified that buying waste oil from the hospitality sector and citizens, along with investment in recycling strategies, would provide an economic boost and reduce the country’s carbon emissions. Embracing the valorization of waste oil for biofuel production would reap the financial rewards of improved food production and seed processing and reduce the competition for land. Additionally, local domestic production can be achieved, reducing over-reliance on imports.
What is the way forward for South Africa? The authors have suggested a number of future strategies that stakeholders can implement. These include the government promoting behavioral change amongst citizens, tax exemptions to encourage cooperation, improving waste collection systems, increasing investment in renewable energy and biofuel production, promoting the design of new infrastructure, and policies which promote diesel-powered machinery over petrol power.
Linganiso, E.C et al. (2022) Biodiesel Production from Waste Oils: A South African Outlook [online] Sustainability 14(4) 1983 | mdpi.com. Available at: https://www.mdpi.com/2071-1050/14/4/198