THE first phase of Hive Hydrogen SA’s green ammonia plant at Coega is on-track to produce by August 2028. With a project value of R105 billion for the first phase alone, this large-scale green ammonia plant will be ready in time to supply a growing demand for green alternatives to fossil fuels.
Hive Hydrogen’s general manager and CEO for Hive Africa, Colin Loubser, says that currently grey ammonia is produced and shipped around the world, but that the green revolution is unstoppable. To get an idea of what’s to come, he points to shipmakers’ order books.
“There are over 100 ammonia-fuelled cargo ships on order and more than 15 very large ammonia carriers (VLACs) on order around the world, dominated by China. The quantum leap to green ammonia is phenomenal and there are a lot of ports already setting up green ammonia bunkering.” Each VLAC has a capacity of at least 60,000 tons.
“Look at what’s going on at COP28, the maritime industry has committed to getting rid of heavy fuel oil and diesel and they’re going to replace it with either green ammonia or hydrogen fuel cells.” Japan and Korea, in particular, have committed to converting their coal power stations to green ammonia.
Closing the price gap
“Combining the latest technology with South Africa’s renewable assets which are very high yield, we can produce hydrogen below US$3/kg which is the threshold to be competitive. In the Eastern Cape, our hydrogen price is below US$2/kg. But we are using our hydrogen to make ammonia only.”
The disincentive to producing green ammonia has traditionally been its very high price. Loubser explains that the price differential between grey ammonia (produced using fossil fuels) and green ammonia (produced with renewable energy) has been shrinking dramatically. “If you look at grey ammonia today, it’s around US$600/ton; a few months ago it was US$300/ton as it’s seasonal and when the Ukraine war started it went up to US$1,600/ton. So it’s a very fluctuating market.”
Two large cost drivers for the production of green hydrogen or ammonia are the cost of renewable energy and electrolysers which are used to split hydrogen (H2) out of water (H2O). Advancements in both these technologies which improve efficiencies and lower costs of production due to scale, are bringing green energy production costs down.
Loubser says that the efficiency of wind turbines has improved dramatically. The new generation of wind turbines are far more efficient. In the past four years, in particular, he says, there have been improvements in the capacity factor for wind and solar. Whereas solar was costing over US$1/Watt, prices have come down to around 10c/Watt. Hive Energy’s mega-projects around the world are helping to drive these prices down, Loubser says.
Over half of the project’s cost is in generating renewable energy to produce green ammonia. Loubser says that for the first phase, Hive Hydrogen SA will be sourcing 1,230 MW of solar power from the De Aar area and wind energy from the Western Cape. Hive Hydrogen will be ‘strengthening the grid’ and wheeling this energy to the Coega site.
Electrolyser technology
With an increase in demand for large-scale electrolysis, there have been advancements in electrolyser technologies. Efficiencies are improving and competition is bringing prices down. Loubser says there are three main types of electrolyser technology. The most efficient are solid oxide electrolysers, but they are very expensive and need to be replaced more often. Alkaline electrolysers have come down in price, and thirdly, there are proton exchange membrane (PEM) electrolysers. PEMs are more specialised and more suited to smaller applications and are less susceptible to fluctuations than alkaline electrolysers.
The proprietary technologies are changing and improving almost month-on-month in China and Europe is adapting to keep up. Loubser says these leaps forward will be where the green delta with grey will really change – as the cost of producing green ammonia comes down.
Desalination
A fortuitous bonus for the green ammonia plant at Coega is that there is an existing desalination plant at the site. Hive Hydrogen is working with the existing Cerebos plant which has been there for decades. Cerebos will use the brine while Hive will use the desalinated water. Because Hive will not be expelling any brine back into the sea, there is no impact on marine life. Loubser says there is sufficient capacity in the two sets of evaporation ponds for the new green ammonia plant.
Ammonia vs hydrogen
The company has decided to build a green ammonia plant at Coega because ammonia is more suitable for storage. Loubser explains that an ammonia plant is a hydrogen plant with the addition of an air separation unit and a Haber–Bosch unit. Hydrogen is a very expensive commodity to store. It has to be stored at minus 260°C whereas ammonia can be stored at minus 33°C so it’s a much more efficient way of storing hydrogen. Ammonia can be ‘cracked’ back to hydrogen, but this will not be done at Coega.
The green ammonia plant at Coega will have two main 35,000 ton tanks and Loubser says ammonia has been an export commodity for the past 60 years, so there is well-established expertise in this regard.
Why Coega
Loubser says there was a strong social motivation to locate the green ammonia plant at Coega, as it will introduce a new industry to the region. It’s estimated that 20,000 direct and indirect jobs will be created in the first phase and 50,000 over the project’s four phases.
“We can bring solar, wind and battery assembly plants at least, as well as electrolyser manufacturing or assembly plants. All these represent tremendous employment potential,” Loubser says.
“We studied 54 ports, and potential ports in Africa and Coega was hands-down the best option. The green ammonia plant at Coega is the only Eastern Cape-based hydrogen project granted strategic integrated project (SIP) status in November 2022. Loubser says the company has received good support from national, provincial and local government and the business community.
