When Qatar Petroleum and Royal Dutch Shell start their Pearl gas-to-liquids (GTL) plant next spring, it will be the biggest of its kind in the world, as well as the most expensive.
When fully operational a year later, the US$19 billion (Dh69.78bn) fuel-processing complex will produce up to 140,000 barrels per day (bpd) of ultra-clean fuel such as diesel and kerosene.
Most of the output will be diesel, suitable for lorries, trains, heavy machinery and portable electricity generators. The plant could also supply jet fuel.
The versatile fuel from Pearl, when burnt, would spew less lung-clogging particulate matter and eye-stinging acid gases into the atmosphere than products refined from crude oil.
Even so, The Wall Street Journalcalled the venture "one of the most expensive gambles on clean fuel in the history of the energy industry". That is because of a price-tag that has ballooned over six years to nearly four times Shell's $5bn estimate.
The project has also been held back by problems that surfaced during the lengthy commissioning process, which began last May. But the delay could be a blessing, as the global stockpiles of transportation fuels left over from the recession have finally started to shrink.
At the same time, gas markets are still glutted because of surging US production from shale deposits. That has caused gas prices to fall relative to buoyant crude, leaving ample room for profits from converting gas into oil.
Soon after start-up, the Pearl project is also expected to yield 120,000 bpd of condensate, a type of light oil produced from gas deposits that commands a premium price because of its use as petrochemicals feedstock.
As a further sweetener, carbon dioxide, one of the plant's most troubling waste products, could be used to boost Qatar's oil output. The economics for that might not work right now, but an agreement on carbon emissions at next month's Cancun climate change conference could quickly change the picture.