African nations have a very specific problem when it comes to dealing with emissions from diesel vehicles.
Because of lax emissions standards, traders import fuel to these countries that is too dirty for sale elsewhere.
But now a handful of African nations are taking a stand against this.
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Last week, five African countries—Ghana, Ivory Coast, Togo, Nigeria, and Benin—announced they would reject shipments of high sulfur diesel fuel from Europe, according to the United Nations Environment Programme (UNEP).
These countries are introducing stricter standards requiring low-sulfur fuels, and demanding that they receive the same quality of fuel offered to European nations.
Nigeria, for one, is cutting the legally-acceptable amount of sulfur in fuels from 3,000 parts per million to 50 parts per million.
The report (pdf) was based on three years of research into the African fuel trade that included sampling fuel directly from pumps in eight countries.
Researchers found that samples contained up to 378 times the sulfur permitted under European regulations.
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Swiss trading firms often produce dirtier grades of fuel—known as "African Quality"—themselves, and then distribute it through fuel stations they control, according to the report.
While these fuels are intended for sale in Africa, they are produced in the "ARA (Amsterdam-Rotterdam-Antwerp) Zone" in Europe, where many of the trading firms have refineries.
This means West African nations that export high-quality crude oil often receive low-quality fuels with high levels of pollutants in return.
Chrome exhaust pipe
Chrome exhaust pipe
The U.S.-based Diesel Technology Forum advocacy group applauded the move, noting that the U.S. diesel industry still thrives under the strict standards currently in place here.
"The five African nations that recognize the opportunity for bringing in cleaner technology and the need for ultra-low sulfur diesel fuel, will move forward," said Allen Schaeffer, executive director of the Diesel Technology Forum.
But actually implementing the ban on high-sulfur diesel fuel could prove difficult.
"It’s not clear their populations can afford the cleaner diesel, or that is there enough cleaner diesel [produced in Europe] to meet that demand," a source in the oil and gas industry with experience in Africa said.
African nations may also lack the infrastructure to enforce a ban, as many cannot locally test fuels for compliance.