COLUMBIA — Columbia's first power plant met the modest electric needs of the city's 12,000 residents in 1910: 208 street lamps, about 15,000 commercial bulbs and 61 private homes.
Coal was abundant and affordable. Trains brought about 12,000 tons of Illinois coal each year. It was burned in a wooden ice house that housed the machinery to make electricity and, “on account of not being fire-proof, is a constant menace to the safety of the plant..." engineers H.B. Shaw and Henry H. Humphrey wrote in a 1910 assessment for the city.
The two engineers predicted that electricity would become a major source of revenue in coming years. Following their recommendations, Columbia rebuilt its power plant on Business Loop 70 in 1912, this time with brick and stone, and installed more efficient equipment to meet growing demand.
Their foresight proved correct. For more than 100 years, coal-fired boilers at the Municipal Power Plant have helped power the city's electric needs.
Just outside the plant, a once-towering heap of coal has been dwindling since the last load, about 1,800 tons of black, nugget-sized chunks of carbon-rich rock from Indiana, arrived by short-line rail on Sept. 1.
It will not be replenished. At 5:30 p.m. Sept. 22, the last day of summer, the Municipal Power Plant burned its last load of coal.
The city-owned plant's two coal-fired boilers join a growing number of small, aging coal-fired units across the country that have gone cold in the face of tighter environmental regulations on emissions. A third boiler will continue to burn natural gas.
Instead of coal, the power plant will conduct trials to burn waste wood, a renewable fuel. Nevertheless, coal continues to supply the vast majority of Columbia's electricity through contracts with larger coal plants elsewhere.
Connie Kacprowicz of Columbia Water and Light said it's been known for a long time that the plant's two coal-fired boilers were old, inefficient and too costly to upgrade to meet EPA standards.
Before this year, power production superintendent Christian Johanningmeier said, the boilers in question, which are both more than 50 years old, burned about 50,000 tons of coal each year to generate electricity during winter and summer months.
Before the last coal was burned, the plant had been running at 30 percent of its normal production to keep its nitrogen oxide and sulfur dioxide emissions within the limits of a regulation that took effect at the beginning of this year, Johanningmeier said. Those emissions react in the atmosphere to form ozone and acid rain.
An EPA rule for mercury and other heavy metals that goes into effect at the start of next year would have further limited coal-fired electric production.
To meet both regulations, Johanningmeier said, the plant would have had to refit the boilers with emissions-reducing equipment costing tens of millions of dollars.
The most pressing, an EPA regulation that manages ash wastes from coal combustion, takes effect on Oct. 19. If the plant were to keep producing ash wastes, Johanningmeier said, the ruling would require the plant to
The plant stores its leftover ash as "wet ash" in a man-made pond nearby that will be dredged of all ash and restored to its original condition, Johanningmeier said.
This is not the first time the plant made changes to comply with more stringent environmental standards. In 1976, the plant decided to burn less Missouri coal, which was expensive and was also polluted more than other coal due to its high sulfur content. Not long after, the city was sued by the Missouri Air Conservation Commission for violating state air emission standards, according to previous Missourian reporting.
Six months later, the plant switched to Illinois coal, which emitted less pollution. In 1979, the plant added a baghouse — a 10 compartment filter through which airborne ash from flue gases are screened before the smoke leaves the smokestack.
Under the latest regulations, it made more sense to end the use of coal rather than pay for additional upgrades, Johanningmeier said.
Although the boilers won't be burning coal any longer, they won't go offline quite yet.
Water and Light expects to receive a permit from the Missouri Department of Natural Resources to burn wood chips in one of the boilers later this fall, Johanningmeier said.
Wood is considered a carbon-neutral renewable resource when properly managed, according to the Food and Agriculture Organization of the United Nations.
The plant will burn Missouri hardwood reclaimed from sawmills. It's provided by Foster Brothers Wood Products in Auxvasse, the same company that supplies MU with wood chips, Johanningmeier said.
Water and Light is studying whether one of the old boilers can be converted to burn 100 percent wood, Johanningmeier said. Pound for pound, wood gives off less heat than coal, he said, so whether enough steam can be produced remains to be seen.
If that idea doesn't work out, the two old boilers will be retired, Johanningmeier said.
Under the city's renewable energy goals, which were approved by voters in 2004, the city has been steadily increasing the amount of renewable sources in its electric portfolio. The goal: 30 percent renewable energy by 2028.
So far, Columbia has been on track to reach this target. In 2014, 7.2 percent of Columbia’s energy came from renewable sources. A half percent came from replacing 10 percent of the coal burned at the plant with wood chips, according to the 2015 Renewable Energy Report.
In the past, Columbia Water and Light has applied for permits to test two other types of biomass as fuels, miscanthus grass and corn stover.
In 2012, the plant tested up to 50 percent miscanthus — a tall, fast-growing, perennial grass — mixed with coal. The biofuel showed potential, Johanningmeier said, but not in that form: “The pellets we had disintegrated before they got to the boiler.”
Columbia also received a permit which expires at the end of this year to burn corn stover, corn stalk and husk waste, mixed with up to 50 percent coal, but delays have kept the corn stover experiment on hold.
That's not to say that Columbia isn't heavily dependent on coal. The Municipal Power Plant supplied 5 percent of Columbia's total electricity in 2014; three-fourths of the city's electricity comes from three coal-fired plants elsewhere.
In Missouri, coal is the dominant fuel source, producing 83 percent of the state's electricity. Nationally, electricity from coal reigns high, although the US Energy Information Administration reported that in April, the electricity generated from natural gas surpassed coal for the first time since the administration started collecting data in 1973.
Nevertheless, investment in renewable energy is a trend in the energy sector, Renew Missouri director PJ Wilson said. Renew Missouri aims to advance renewable energy efficiency and policy in the state of Missouri, he said.
“We’re not seeing any new coal going right now, very little natural gas, no new nuclear plants,” Wilson said, “and we like that.”
In Missouri alone, six coal power plants have been retired or committed to retire in the last two years, including the Columbia power plant, Andy Knott of the Sierra Club's Beyond Coal Campaign said.
All are old, outdated, and lack the modern pollution controls and safeguards to meet EPA standards, he said.
“It’s generally not economical to build coal plants right now,” Knott said. “It’s cheaper and less polluting to go with cleaner forms of energy.”
He commended Columbia for adopting the first renewable energy standard in Missouri.
“Columbia is very progressive,” Knott said. “They kind of know what they’re doing.”
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