Engineers who worked on Southern Company’s Kemper coal plant say the proposed start-up date of September 2016 is as unrealistic as previous dates given by the company and that the plant is unlikely to go on-line before sometime in 2017.
One of the engineers, Brett Wingo, who blew the whistle on schedule delays at the plant in a New York Times investigation earlier this month, noted that aside from the gasifier itself, which is supposed to turn lignite coal into synthesis gas, or syngas, there are numerous other first-of-its-kind systems that Southern is not publicly acknowledging as likely delaying factors in its bid to put its “clean coal” power plant – already two years behind schedule and almost $5 billion over-budget – on-line.
These new, untested technologies include the key systems that transport and dry the low-grade lignite coal mined adjacent to the plant, and others that treat the syngas and remove pollutants, including carbon dioxide.
The plant is supposed to remove 65 percent of the CO2 it produces, making it roughly equal to a natural gas plant in its carbon footprint, and pipe it to oil fields in the region to coax more oil from underproducing wells. The plant has been running on conventional natural gas since the summer of 2014.
So far, Southern has focused attention on generating syngas as the limiting factor in getting the plant into commercial operation. In a Securities and Exchange Commission filing yesterday, Southern projected August as the date for “reliable syngas” production, with September still the date for commercial operation.
But Wingo, and another engineer expert in gasifier technology, both noted that there are numerous other kinks that will have to be worked out before Kemper can be declared “in-service,” at which point Southern is expected to move immediately to get its Mississippi customers to pay for a big chunk of the plant’s $6.8 billion cost.
Just how much still isn’t clear, but is a major worry to customers of Southern – or rather Mississippi Power, Southern’s Mississippi subsidiary, the plant’s operator.
The engineers point out that once debugged, the individual systems then have to be made to run “synchronously” – like the cylinders in an auto engine – to keep the plant running smoothly and producing electricity. A breakdown anywhere in the chain will shut the plant down for what would almost certainly be lengthy and expensive repairs.
Another sticking point is the gas-fired turbines at the plant, which are part of the “power block” that actually produces electricity, as opposed to the gasifier island which makes the syngas and sends it to the turbines. First, the two Siemens turbines, designed for natural gas, have never before been run on syngas, and the control system for the power block will have to be integrated to run in tandem with the brand-new, untested control system for the gasifier.
About two months was supposed to be allocated for the integration of the various gas clean-up systems that will remove CO2, sulfur dioxide and other pollutants, with at least four months more to solve problems in the power block and coordinate the turbines with the gasifier – – adding at least another six months to the proposed September start date.
That would put commercial operation off at least until January 2017.
But that’s not all.
An important lodestar for estimating the cost and completion date for the Kemper plant has been the Edwardsport coal plant operated by Duke Energy in Indiana.
According to a heavily redacted document obtained by the Sierra Club, a team from Southern Company – actually from Mississippi Power, the Southern Company subsidiary that operates Kemper – visited Edwardsport on October 18, 2010, generating a 16-page presentation to company officials a few days later. This was only months after ground was broken on the Kemper plant.
Virtually the entire document has been redacted by the company, leaving only the dates and the names of personnel involved, but Edwardsport has repeatedly been cited by company officials as a guide to what Southern might expect at Kemper, according to both the engineers and internal company records.
However, the Edwardsport analogy is way off, according to the engineers.
Duke declared Edwardsport operational in June 2013, but the plant in fact was barely functional and lawsuits were filed alleging Duke’s declaration was premature and a pretext for passing on costs for testing and tuning the plant.
While Edwardsport uses a gasifier to turn coal into syngas, there the analogy with Kemper ends. Edwardsport does not capture CO2 and is not a particularly clean coal plant, according to a study done by the Citizens Action Coalition in concert with the Sierra Club and others.
In addition, the General Electric gasifier used at Edwardsport was not the first-of-its-kind design, but had been in use at the Polk Power Station run by the Tampa Electric Company for more than 15 years, and there are more than 70 GE gasifiers operating around the world on different fuels making syngas for chemical synthesis.
In an email, one Kemper engineer summed up the problems with comparing Edwardsport to Kemper:
Given all the previous experience with the gasifier, the engineer wrote, “design and operating issues should have been reasonably resolved and successfully addressed in Edwardsport’s design and engineering phases.
“In spite of such vast experience and a successfully operating Polk plant with high availability, it is apparent that new issues during the commissioning stage have caused the Edwardsport’s commissioning to last more than 7 months,” he wrote.
“In contrast, the integrated Kemper plant is first of the kind; it is unavoidable that unanticipated issues will appear during the commissioning stage. Issues on [a} commercial scale take considerably more time to resolve. We should be mentally prepared and allocate time for such occurrences.”
Another issue – and a large one, according to the engineer – are differences in the coals used at the two plants.
Edwardsport uses a bituminous coal from Indiana which doesn’t require drying. Kemper uses extremely-moist lignite coal from its adjacent mine, which is much more difficult to handle and requires drying and other preparation.
“Furthermore, since the coal preparation is at the front end of the entire IGCC system, without the coal preparation system operating smoothly and in full swing, the downstream system cannot be commissioned,” he wrote.”Everything being equal, this coal drying step alone will make the Kemper plant commissioning time much longer than Edwardsport,” the engineer explained in an internal communication in 2014.
According to these experts, if you add up all the new and untried systems and all the unknowns, it’s unrealistic to count on Kemper going on-line before mid- or even late 2017.