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14 www.coalage.com March 2017 coal-fired power IGCC Technology Coming of Age Eyeballed by Asia and Europe, tested in the U.S. at a cost, coal gasification power proves promising By Jesse Morton, Technical Writer Too old to be babied, yet still too young to be blamed, integrated gasification com- bined cycle (IGCC) technology is slowly emerging from adolescence. While there are hundreds of pulver- ized coal-fired power plants in the U.S., there are only three operational IGCC power plants stateside. The eldest IGCC facility celebrated its 20 th anniversary of operations last year, and it no longer uses coal due to costs. Its youngest sibling is double its size, more complex, and con- sistently garnered maudlin headlines over the last half decade as it exploded budget constraints and repeatedly missed dead- lines while ramping up. The middle child, also double the size of the eldest, during ramp-up was such a locus of scandal an executive told the local daily it would "need an exorcist." 1 Their parents were prototype facilities, conceived in the pub- lic sector and academia, birthed in the private sector, coddled by government, and now either closed or converted. One is currently being repurposed to make fertilizer. Abroad, IGCC has met perhaps more success and interest, specifically in countries with high coal and low natural gas reserves. This snapshot perhaps lends to cyni- cal conclusions unnecessarily. No doubt, cheap natural gas from north-central Ap- palachia is killing more than just the U.S. coal sector. Nuclear plants nationwide are getting the axe, and uranium miner Came- co recently vaporized jobs after shuttering a mine and attempting to placate stam- peding investors. Indeed, IGCC is in good company as a viable technology that has been sidelined by the advent and deploy- ment of innovative hydraulic fracturing drilling technology making Marcellus shale-bound gas accessible. In this economic environment, all three IGCC plants face challenges and un- certainty, but ultimately will prove to be viable at generating low-emissions power from coal, advocates and experts say. They also say prospects for IGCC technology are promising, thanks in part to lessons learned the hard way. Hard lessons come quick when build- ing a modern engineering marvel. Engineering a Tourist Attraction In layman's terms, an IGCC plant treats coal to release gases that are cooled and cleaned to create a fuel gas called syngas, comprised of carbon monoxide and hy- drogen. Syngas is burned to turn a turbine. For the combined cycle part, heat gener- ated in the process turns water to steam, which spins a turbine. The U.S. Department of Energy (DOE) provides details. The coal "to be gasified is combined with steam and limited ox- ygen in a heated, pressurized vessel. The atmosphere inside the vessel is starved of oxygen, and the result is a complex series of reactions of the feedstocks to produce syngas," DOE, via the National Energy Technology Laboratory (NETL), reported. During that stage, much of what would have become airborne particulate matter were the coal burned remains in the slag. Tampa Electric Co.'s (TECO) integrated gasification combined cycle (IGCC) unit, Polk 1, celebrated its 20 th anniversary last year. Knowledge gained from Polk 1 was used in designing and launching Duke Energy's Edwardsport, Indiana, IGCC unit, which is meeting milestones after being at the center of scandals and controversy when its launch missed deadlines and broke budgets. (Photo: TECO)