Ergo Exergy - UCG

UCG Myths


“El sueño de la razón produce monstruos”
– Francisco de Goya

For a century, Underground Coal Gasification has been surrounded by an aura of mystery and suspicion. Not all of the minds which have been intrigued by UGC are well-informed, or indeed well-intentioned. A mixture of mystery and ignorance sometimes spawns a superstition. Ergo Exergy is compiling a library of what we call "UCG myths". These myths defy logic and disregard the reality, yet they are sometimes difficult to expose. They are not that innocent and harmless: in reality, they are capable of contaminating the minds of those in regulating offices, investor circles, environmental groups, and local communities.

Please send us the UCG myths you have encountered in your UCG activities.

For further reading on the theoretical basis of the issue, please click on the following link: Philosophy

UCG Myths exposed:

"UCG is environmentally dangerous – groundwater, subsidence, unquenchable fire, it causes landslides..."

Out of 33 UCG trials conducted in the USA in the 1970s and 1980s, only two reported environmental problems: all others were environmentally benign. The Rocky Mountain 1 UCG project (1988) has demonstrated no groundwater contamination.
UCG operations in Chinchilla, Australia continued for 30 months and showed no groundwater contamination and no environmental problems whatsoever.

Published reports on Soviet UCG plants claim no contamination in the course of, and subsequent to, large scale UCG operations there. (Please find further information on this matter in εUCG & the Environment)

"UCG is expensive - not cheaper than natural gas!"

This is not a myth but the plain and solemn truth about cost projections of many UCG technologies on offer today (we say "projections" because no commercially proven technology is available today, except for εUCG™). However, the above statement is mythical if applied to εUCG: our gas can compete in cost with locally-produced coal and is therefore much cheaper than natural gas for most energy markets.

(You'll discover further myth-busting information on this matter in Why εUCG?)

"UCG is uncontrollable - the gas quality is highly variable and unreliable!"

Many UCG trials conducted in the West in the last 30-odd years seem to confirm this statement. Even the CRIP technique proposed and tried in the 1980s in the USA has not ensured stable gas composition.

In stark contrast to these trials and experiments, εUCG has demonstrated reliable, consistent and stable gas composition on many occasions including the 30 months of gas production in Chinchilla, Australia. In addition, continuously-stable gas composition had been demonstrated in UCG operations in the former Soviet Union. Properly designed and implemented, a large-scale εUCG gas plant produces very consistent and controllable gas quality. It has been proven that the gas can be used as raw material for a number of chemical syntheses.

(You can read further myth-busting information on this matter in εUCG)

"If it is better than coal-firing - it will make much wider use of fossil fuels more palatable and that will eventually lead to more CO2 emissions."

At a first glance, this seems quite logical, doesn't it? The underlying myth in the above statement is the notion that the modern world today can get by - and even prosper - using solely renewable sources of energy like the wind, solar power, geothermal energy, hydroelectric power and so on. We hope this may come to pass sometime in the future, but until then, we need to use fossil fuels to sustain life as we know it. Ergo Exergy believes that εUCG technology may play a major role in making the use of coal environmentally acceptable.

Please see εUCG & Global Warming for further discussion.

"If it's so good, UCG would already be used in the US!"

This statement, so surprisingly common among the skeptics, is implying that every good thing that ever existed has been implemented in the US first. Do we really have to respond to this comment? Besides, εUCG is being implemented in the US where feasibility studies for two major projects have already commenced.

"UCG gas is not suitable for modern gas turbines"

The εUCG syngas is a perfect fuel for a GTCC plant. Please refer to εUCG &Power Generation.

"The gas is impossible to clean up!"

Raw εUCG gas is similar to the products of coking, conventional gasification (e.g. the Lurgi process) and many other coal processing technologies. These gases have been routinely cleaned up, processed and conditioned for various use for many decades now.

"UCG is not scalable (can't be used at a large scale)."

The εUCG technology is a modular process that uses production modules with an individual capacity of at least 100,000 metric tonnes a year. Any number of these modules can be used to reach any scale of gas production required. That's why all Ergo Exergy projects are targeting a scale of at least 300,000 tonnes a year. The largest project under development is to extract approximately 7 million tonnes of coal a year.

(See Ergo Exergy Projects for more details)

"To be safe and environmentally acceptable, UCG requires coal seams at a depth of at least 600 meters."

All the Soviet UCG plants worked at shallower depths than 600 meters. All UCG trials in the US have been conducted at the shallower depths, too. The Chinchilla UCG project used coal at the depth of 140 m. Ergo Exergy is comfortable in applying εUCG technology at the depths anywhere from 30 to 800 m.

Please refer to What is εUCG?

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