Chasing rainbows?

Alternative fuels are all the rage, but is South Africa ready for them? Should we, rather, be focusing on getting the foundation right and using technology that could work on the continent before we pursue this route? JACO DE KLERK reports.

Sunny South Africa is a wonderful country, but it does have its own set of unique challenges. Loadshedding, corruption, sub-par infrastructure: the list goes on…

The world is embracing alternative fuels and electric drivetrains in a race to combat the scourge of global warming. While this is great (the future will be dismal if we don’t do everything that needs to be done to fight this plight), are alternative fuels really the correct fit for the South African context? Personally, I don’t think so. We don’t have power and, when we do, it comes from “dirty” power stations. At the moment, this means the electric route is blocked (I truly hope this changes).

Hydrogen, meanwhile, can only work if the infrastructure is pristinely managed, as Neil Thomas Stacey highlights in his article Selectivity needed when making and using hydrogen fuel, which appeared in FOCUS last August.

Stacey notes that hydrogen is an escape artist: “It is a tiny molecule which can get through all kinds of materials that are considered airtight. Some leakage is unavoidable no matter what the application. Hydrogen can even pass through solid steel (albeit slowly). It can be leaked through imperfectly sealed or damaged equipment, and released either as waste gas or during the shutdown or start-up of a plant.”

This is worrisome, as hydrogen acts as an indirect greenhouse gas (GHG), mainly by slowing down the breakdown of methane, which has powerful direct GHG effects. “This has been known for a while, although the effect has been considered negligible,” Stacey writes.

“In recent research commissioned by the UK government, researchers from the universities of Cambridge and Reading have now re-examined hydrogen’s greenhouse gas effects, factoring in atmospheric layers not previously considered. They found that hydrogen’s Global Warming Potential (GWP) is more than double previous calculations,” he continues.

Stacey says that GWP is a ratio of a particular gas’ global warming effects to those of an equivalent mass of carbon dioxide (CO₂), while different GHGs exert their effects over different time periods. “Hydrogen’s GWP-20 (its effect over 20 years) is now estimated at 33 and ranges between 20 and 44,” he points out. “This means that over the course of the next 20 years, each tonne of hydrogen entering the atmosphere will cause approximately 33 times as much global warming as each tonne of CO₂. Over a time period of 100 years, hydrogen’s GWP-100 ranges between six and 16.”

These alarming statistics suggest that we should re-examine some of our plans for using hydrogen to replace fossil fuels. Things can’t be left unchecked, however, as global warming isn’t the only concern. In their report, Soot-free road transport in South Africa: A cost-benefit analysis of Euro 6 heavy-duty vehicle standards, Yihao Xie, Francisco Posada, and Arijit Sen state that the challenge of poor air quality acutely affects African nations, including South Africa.

“In 2019, 383 000 deaths were attributable to ambient fine particulate matter (PM2.5) pollution in Africa, an increase of 7% from 2015, with the greatest increases occurring in the most highly developed African countries,” notes the report. “In South Africa, air pollution ranks as the number one environmental risk factor related to health, and is the eighth leading overall risk factor for deaths and disability in 2019.”

The report points out that in 2015, transportation was responsible for 7% of deaths caused by exposure to PM2.5 and ozone in South Africa. Of these deaths, 48% were attributed to on-road diesel vehicles.

“Severely outdated vehicle emission standards have contributed to this deadly air pollution: the current heavy-duty vehicle (HDV) emission standards in South Africa are Euro 2, first introduced in Europe more than 20 years ago and phased-out long ago there and in other major economies,” the report reveals. “South Africa has not updated its official emission standard regulations since adopting Euro 2 standards in 2006. Diesel engines that lack modern emission control devices produce PM2.5, soot, nitrogen oxides (NO_X) and other pollutants in large quantities.”

The authors highlight that South Africa’s diesel fuel in the retail market is approaching the level of sulphur content required for Euro 6 HDV emission standards: “The vast majority of South Africa’s diesel fuel has sulphur content lower than 50 ppm, which is suitable for Euro 4 emission standards. In August 2021, South African regulators published new regulations that will limit diesel sulphur content to 10 ppm, effective in September 2023.”

This puts South Africa in a strong position to formally adopt Euro 6-equivalent emission standards, thereby reducing air pollution and the health risks associated with it. “Such leapfrogging has a precedent in India, where the government successfully jumped from Euro 4-equivalent to Euro 6-equivalent emission standards in 2020, under similar conditions of low sulphur diesel availability in the market,” the study points out.

In this context, the authors evaluate the impact of advanced HDV emission standards in South Africa for three scenarios, along with a baseline scenario that continues the trajectory of current emission standards and announced fuel quality improvements. The assumptions include:

Baseline: South Africa implements the planned 10-ppm sulphur diesel content limit in 2023, but maintains the current HDV emission standards. Without precise market share information by emission standard, the authors assume new vehicles in South Africa meet Euro 3 standards for trucks and Euro 4 for buses from 2016 onward, noting: “This differs from the Euro 2 emission standards officially in place, but reflects our understanding of the market in practice, based on information provided by industry experts and government officials.”

Incremental transition to Euro 6: South Africa implements Euro 4 emission standards in 2024, followed by Euro 6 standards in 2027.

Leapfrog to Euro 6: South Africa implements Euro 6 standards in 2024.

Beyond Euro 6: South Africa implements Euro 6 standards in 2024, then implements Euro 7-equivalent next-generation emission standards in 2030.

“In the baseline scenario, PM2.5 falls with the availability of 10-ppm sulphur diesel in 2023 before picking up again with increased vehicle fleet size and activity. By 2050, the levels of PM2.5, NO_X, and black carbon (BC) emissions will be 24.9%, 55.5%, and 25.3% higher compared to 2021 levels, respectively. The 10-ppm sulphur diesel limit under the baseline scenario leads to an 83% decrease in sulphur dioxide (SO₂) emissions from 2022 to 2023 since there is less sulphur in the diesel to produce SO₂,” the study finds.

“Adopting modern emission standards can drastically reduce air pollution from South Africa’s HDV activities. In the most conservative ‘incremental transition’ scenario, emissions of PM2.5, BC, and NO_X in 2050 would be reduced by 99.0%, 99.8%, and 93.0% compared to the baseline. ‘Leapfrog to Euro 6’ would deliver even greater emission reductions in the near to mid-term, due to the earlier adoption of Euro 6 standards, while annual emission levels in 2050 would be similar between these two scenarios,” it continues.

The “Beyond Euro 6” scenario further reduces NO_X emissions by 89.0% in 2050 compared to the leapfrog scenario, and by a staggering 99.2% compared to the baseline. “With the proposed Euro 7 standards [which place limits on non-exhaust emissions, starting by particle emissions from brakes] assumed in this scenario, NO_X limits are nearly 10 times more stringent than the current Euro 6 standards allow,” the report asserts.

So, is there really a need to chase rainbows by trying to leapfrog even further, straight to alternative fuels and electric drivetrains?

It would seem that the local transport industry can make a significant contribution towards everyone’s well-being in sunny South Africa, if it first gets the foundations right and systematically steps up to higher Euro emission levels, and then takes things from there.