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From trash to energy

1 percent of city energy could come from the landfill
Sunday, October 17, 2004 | 12:00 a.m. CDT; updated 5:11 p.m. CDT, Saturday, July 5, 2008

It stinks.

It’s usually kept out of sight. And most Columbia residents routinely get rid of it each week, happy to discard the stuff by their curbs without much thought.

Call it garbage, waste, refuse or trash. But soon, today’s trash could be generating the electricity that lights your living room or powers your coffee maker. When garbage decomposes, methane gas, which can be harnessed and used for energy, is emitted. Columbia’s landfill currently has enough buried waste — more than 2 million tons — to pursue a landfill gas-to-energy project.

Richard Wieman, solid waste utility manager for the Public Works Department, said Columbia’s landfill will definitely pursue a landfill gas-to-energy project, but the city is still uncertain where or how the energy will be used. Columbia will be the first municipal landfill in Missouri to harness its underground resource and the fourth landfill-to-energy site in Missouri.

The city has hired Aquaterra Environmental Solutions, a Kansas City-based consulting firm, to provide plans for three options for the landfill: on-site heating and electricity; pumping the gas to a nearby industry such as Kraft Foods; or installing micro turbines to generate electricity for Columbia Water and Light.

The municipal utility’s staff estimates that methane gas at the city landfill could provide up to 1 percent of the city’s power needs in 2007. That small chunk of power is the equivalent of 12,500 megawatt hours of electricity per year, enough to annually supply 1,122 Columbia homes.

That 1 percent represents half of the renewable energy requirement in the proposed ordinance on the Nov. 2 ballot. Voters will decide whether to require the municipal utility to purchase 2 percent of its power from renewable sources by the end of 2007, and to incrementally increase the required percentage of renewable energy to 15 percent by the close of 2022. The ordinance also prohibits electric rate increases of more than 3 percent to accomplish this goal.

John Coffman, former City Council member and member of Columbians for Clean Energy, the group that proposed the ordinance, said this cost cap is an important protection for consumers. But people should know that the city would still be required to purchase as much renewable energy as possible without exceeding the 3 percent rate increase, he said.

Regardless of the ballot initiative’s outcome, the city’s power company is actively pursuing more diverse energy sources. On Monday, Columbia Water and Light plans to present a proposal to the council to purchase wind energy from Kansas and landfill gas energy from either the city landfill or Missouri Public Utility Alliance.

Dan Dasho, Water and Light director, said the city is also considering borrowing an anemometer from the state Department of Natural Resources to determine whether Columbia generates enough wind power to harvest as energy.

Unlike coal, oil and natural gas, renewable energy is generally considered an inexhaustible energy source. With the price and availability of fossil fuels subject to Middle East politics and unpredictable market forces, utilities, local governments and large corporate users increasingly consider renewable energy as a long-range alternative.

“I think the technology, in terms of cost for building it, has really gotten a lot better, and the pricing on it is certainly becoming more in line with existing resources,” said Dasho who moved to Columbia from Wisconsin. While there, he sat on a committee that worked to pass a renewable energy standard for Wisconsin. “I can go out and buy it tomorrow; the question is, how much can I get?”

Columbia gets its energy from four sources in decending order: AmerenUE, the Board of Public Utilities in Kansas City, the Sikeston coal-fired plant in Fulton, and the city’s Municipal Power Plant.

For example, Columbia’s average minimum energy load was about 70 megawatts in September, while the maximum was 190 megawatts. At 70 megawatts, Columbia draws its energy from AmerenUE and BPU only. At the maximum, it draws energy from all four sources, said Jim Windsor, rate manager at Water and Light.

Dasho said Water and Light could meet the ordinance’s 2 percent renewable requirement with only a 1 percent rate increase in consumer utility bills. For a $50 electric bill, that amounts to 50 cents per month.

Why now?

The proposed ordinance is the culmination of years of grass-roots efforts by local groups such as the League of Women Voters and the Sierra Club. Coffman and other members of Columbians for Clean Energy — notably Win Cowell of the League of Women Voters and Chris Hayday of the Sierra Club — have advocated renewable energy and cited concern for human health and the environment and a need to reduce dependency on fossil fuels. A general feeling that city officials were dragging their heels on initiating renewable use also prompted Columbians for Clean Energy to propose the ordidance.

Record prices at the gas pump and increasing energy costs — including a recent 9 percent electricity rate increase by Columbia Water & Light — led enough community members to think that the time was right to propose that the city use a certain amount of renewable energy annually.

Dasho, who arrived this spring from Shawano, Wisc., has also made it a priority, said Jay Hasheider, a city utility engineer.

“For several years, we’ve been asking customers if they are interested in alternative power sources, and when the new director came in, he indicated a positive interest in green power and allowed us to move forward in investigating it,” Hasheider said.

For Dasho, while recognizing the environmental concerns behind the push for renewable energy the bottom line is the most important factor in determining energy purchases.

Some skeptics suggest that renewable energy, which in Missouri remains a niche market, will never compete with the entrenched economic and cultural forces of coal, oil and natural gas.

Dasho disagrees.

“To say it’s not viable is just not true,” he said. “Right now, you can go out on the marketplace and people will quote you a price and deliver you green energy.”

For Coffman, who has years of experience working in utilities, the choice is about economic viability and creating a healthy environment for future generations.

“The regulations on coal are just going to tighten, mostly because of the mercury, but there are a variety of toxins that come out of coal — it is really a major negative impact on the air, streams and environment in general and on health,” he said. “There are several thousands of deaths a year that you can attribute to coal-fired emissions.”

“If you vote for Prop 3 (the renewable energy initiative), you’re definitely voting for the city to take a step toward cleaner air,” Coffman said. “I’m involved in this because primarily I want my kids to grow up in a city that is reducing its air pollution. Why should I care if there is a windmill blowing in Kansas? Because then there’s less coal to burn here and the coal plant is putting less pollution in our air.”

According to the state DNR, the Columbia Municipal Power Plant emitted 96,000 tons of carbon dioxide, 723 tons of sulfur dioxide and 272 tons of nitrogen dioxide during 1999. These figures don’t include mercury or other fine particles emitted from the plant, or emissions from the other coal-fired plants that provide the majority of Columbia’s power.

According to DNR reports, nitrogen dioxide can lower resistance to infections such as bronchitis, and it is suspected of causing acute respiratory diseases in children. Sulfur dioxide can cause irritation of the lungs and throat, and aggravate existing cardiovascular or respiratory illness.

Hayday said burning less coal, which would reduce mercury emissions, could mitigate problems with Missouri waterways and lower the number of areas where the fish are deemed unsafe to eat.

He pointed toward efforts in Kansas City, where the city’s utility is considering building a 200 megawatt wind farm. The utility backed off a plan to build two new coal-fired power plants and is building only one instead.

An outside view

Missouri currently has three landfill gas energy projects. In St. Louis, Fred Weber Inc. collects methane gas to fully heat Pattonville High School and saves the public school more than $50,000 per year over its previous utility costs. The company also relies on its landfill to power an on-site asphalt plant and nearby greenhouse.

Onyx, another St. Louis company, pumps methane gas from its landfill to the DaimlerChrysler factory near St. Louis, and the Rumble landfill near Kansas City heats a nearby greenhouse with landfill gas. Together, the plants produce 4,000 cubic feet per minute of landfill gas, which gives them a combined 11 megawatts capacity potential.

Those efforts have been supported by the Environmental Protection Agency. The current use of landfill gas in Missouri is equivalent to planting 140,000 acres of forest, replacing one million barrels of oil, removing the emissions of 100,000 cars annually, or offsetting the use of 2,000 railcars of coal, said Chris Voell, a Washington-based EPA official who oversees the Midwest’s Landfill Methane Outreach Program.

Voell predicts Missouri landfills could generate 50 to 60 megawatts, which is at least four times as much as the current rate generated and enough power for about 33,000 average homes annually.

The city estimates Columbia’s landfill could continuously produce 1.6 megawatts, and according to average use in Columbia, that could power more than 1,000 homes.

Columbia’s landfill is one of 20 prospective sites in Missouri for the methane gas conversion, according to the EPA. If each of those landfills harvested methane, Missouri could offset 12,000 rail cars of coal, or the equivalent of removing the emissions of 560,000 cars, the EPA projects.

According to the EPA, more than 600 other landfills nationwide could harness their methane for energy, which could produce enough electricity for 1 million homes. That would equate to removing gas emissions from 13 million cars a year.

Beyond offsetting the use of fossil fuels, harnessing and combusting landfill gas for energy has other substantial environmental benefits.

By collecting the methane and either burning it with a flare, as Columbia currently does, or using it to produce energy, landfills prevent the dangerous greenhouse gas from escaping into the atmosphere.

Once the methane is burned, it is broken down to water vapor and carbon dioxide. This process also prevents methane from escaping from the landfill and collecting elsewhere, posing an environmental and explosive risk, said Frank Dolan, an environmental engineer for the DNR.

According to the EPA, landfills account for 33 percent of methane emissions in the United States.

Collecting the landfill gas also helps protect groundwater. The collection process at landfills brings other organic compounds to the surface where they can be eliminated or significantly reduced, instead of remaining below the surface and possibly seeping into groundwater.

Michele Boussad, the Aquaterra project manager evaluating Columbia’s landfill, said many landfills in Missouri are interested in landfill gas use but are waiting for possible federal incentives.

However, landfills, such as Columbia’s, have discovered that there is an economic benefit to using the gas right now. Whether Public Works sells the gas to a local industry, uses it on site or sells it to the city utility, they will be making money on an untapped resource and offsetting the use of traditional energy sources.

Considering the 650 tons of trash Columbians generate daily and the landfill’s capacity to expand for another 75 years, the amount of renewable methane energy should grow.

Currently Public Works is burning off the methane from the 32 wells collecting the gas at the city landfill. Many more wells are proposed. To harness methane gas for energy, the city’s Public Works Department would not need to modify the existing wells, but rather continue to add more, said Richard Wieman, the city’s solid waste utility manager.

The amount of methane produced will also vary depending on whether the city chooses to install a bioreactor at the landfill. A bioreactor basically increases the moisture content in the trash, which then stimulates methane production. Currently the landfill is designed to keep waste dry.

Floyd Cotter, an Aquaterra project manager, said Kraft Foods is a likely candidate because of pure economics. Piping the gas to Kraft to be burned in a boiler to generate steam in the industrial process represents a “direct use” of the landfill gas, meaning few modifications would have to be made to the gas.

Aquaterra is suggesting plans for all three potential users, however, including Columbia Water and Light. The city already has a substation in the vicinity, but creating a facility to turn the gas into electricity would require an investment of $1.5 million to $2 million. To pay for the facility, a 0.2 percent rate increase was proposed by the advisory group. That’s a 20-cent increase for a $100 electric bill.

For on-site use, the city is considering a version of the system at Columbia’s waste water treatment plant, which has been collecting and using methane for its own energy needs since 1983.

The waste water plant harnesses methane by burning sludge left behind in the water treatment process. The gas provides more than 20 percent of the plant’s electricity, heats its buildings in the winter and is used to mix the digesters in the water processing tanks, which create more methane.

Superintendent Joel Gambill said the plant has cut its yearly fuel oil costs from $30,000 to $3,000 by using the methane mix.

Locally, some utility customers already have an opportunity to have renewable energy.

Boone Electric Cooperative offers green energy for an additional premium of $2 per 100 kilowatt hour blocks. Currently 78 customers are purchasing a total of 257 blocks of renewable energy, said Chris Rohlfing, the co-op’s manager of member services. The current supply comes from ground-up walnut shells, but the company can also grind up corn or other materials to burn and create energy.

What’s on the horizon?

Methane is not the only source of renewable energy the city is pursuing. The Water and Light Advisory Board has compiled estimates showing that the city can obtain 1.6 percent of local energy needs from wind power.

According to its estimates, the city could purchase 19,700 megawatt hours of energy per year for $731,000. However, when the cost of the conventional power sources it would replace are subtracted, the additional cost would be $460,000.

The advisory board estimates that a 0.6 percent rate increase could cover the cost of the wind power. Many renewable advocates, including Hayday of the Sierra Club, are pushing for increased production of wind resources because of the significant health and environmental benefits . Those benefits are not considered in the advisory board’s equation, though.

“The raw amount of wind energy power is phenomenal,” said Rick Anderson, a state DNR energy policy analyst.

Anderson cautioned that the costs are substantial and complicated, however, because of federal policy and variations across state lines over transmission issues.

“Organizations don’t want to invest in upgrades until they know they will receive a return,” he said.

The potential, though, is vast. Tom Welch, a federal Department of Energy spokesman in Washington, said the wind power from three states alone — Kansas, North Dakota and Texas — could supply the United States’ entire energy needs “one-and-a-half times” over.

For Columbia to get a substantial amount of its power from the available resources in Kansas, some significant improvements would have to be made to the utility grid in Kansas City. Dasho said the energy traffic at Kansas City creates a bottleneck, making it difficult but not impossible to import large amounts of wind power from west of Kansas City. Currently the Missouri Public Service Commission is working to track those transmission issues across state borders, Anderson said. Brenda Wilbers, the DNR program director for energy policy and analysis, said the next step in evaluating Missouri’s wind potential is on-site measurement and analysis. Sophisticated computer mapping has already been done to identify the best places for wind harvesting, which are mainly located in the state’s northwest corner.

But to accurately evaluate the power potential of these sites, Wilbers said, the state must build towers to take readings. DNR is currently loaning out 10 anemometers designed to gather data for small-scale individual wind power use

Wilbers said that researchers in Iowa are currently working on developing ways to store electricity generated by wind.

For Jim Windsor, rate manager for Columbia Water and Light, that’s the direction the city should be headed.

Windsor and others in the electric utilities business are concerned about the natural variations in wind power. He said the real potential for wind rests with using windmills to generate electricity by separating hydrogen from water and using it to power individual fuel cells.

The advantage of fuel cells is that they have the potential to continuously meet energy needs just like the fossil fuels power plants burn now, but they don’t have the environmental or health costs.

With individual hydrogen fuel cells, utilities would still supply customers with fuel and equipment, but each home would essentially have its own energy supply, Windsor said.

For now, that innovation is very preliminary.

“We’re talking about it right now, but the price is outrageous,” he said.

For Freddie Fletcher, the questions of cost and benefits are more than just hypothetical. Each day, Fletcher, a city Public Works employee, hauls countless bags of garbage to the Columbia landfill.

As the truck he rides on rumbles slowly down Ash Street, Fletcher pauses to consider the ballot proposal. He doesn’t know much about the specifics, but poses a question that will likely prove pivotal to the measure’s chances of success early next month.

“It’s a good idea, but (what) I want to know is, will it reduce costs for the people?” he said.

That depends on who you ask. Columbians for Clean Energy certainly weighs the health and environmental costs when considering energy decisions.

“The price of renewable energies continues to go down while conventional sources go up — there should be a crossing point soon,” Dasho said. But the city doesn’t factor environmental or health costs into the equation for determining the price of power, and neither does its largest electricity supplier, AmerenUE.

Mike Cleary, an AmerenUE spokesman, said statistics demonstrating environmental and health costs are questionable.

“Emissions from power plants travel vast distances, so how can you (tell) where there is an impact?” he said.


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