As the city looks for ways to meet voter-mandated goals for using renewable energy, part of the conversation has turned to exactly what forms of energy qualify as renewable.
“Wind, solar and hydro are pretty apparent,” said Dan Dasho, director of Columbia Water and Light.
Other areas can be a little more complicated.
The Water and Light Department staff, for example, suggested the possibility of putting conservation measures under the renewable energy umbrella. But that idea wasn’t acceptable to the Environment and Energy Commission because saving energy rather than purchasing energy can be difficult to measure.
The Environment and Energy Commission also discussed whether some forms of biomass energy — pellets, for example, made from paper products recovered at the landfill — are more of a waste product than a form of renewable energy.
Biomass, or energy derived from plants, could be more readily available than wind, solar or hydropower, but questions remain as to how renewable it is. The Environment and Energy Commission considers biomass to be more of a recyclable energy form than a renewable.
The two advisory boards have since settled on a definition of renewables. Conservation is out; solar, wind, hydropower, biomass, geothermal and “green tags” are in.
Andrew Spain, chairman of the Environment and Energy Commission, said his board wants the city to make use of more conventional renewables before considering alternatives such as biomass.
“It’s a real fine balancing act between what we would like to use and what is most realistic,” he said.
Wind, solar and hydro energy are all challenging to use in Missouri because of limited supply at this time. By the time the city is required to meet the 10 percent threshold in 2018, Dasho said, renewable energy will be more readily available.
Wind energy is highly variable, Dasho said, and the peak time for wind production is during the winter, while the peak demand for electricity occurs during the summer. Also, Missouri does not have the greatest potential for wind energy compared to states like Kansas and Iowa, Dasho said. Still, the first wind farm in Missouri will be partially completed by the end of the year.
Purchasing wind power from Kansas can be difficult due to unreliable transmission caused by a bottleneck in Kansas City, Dasho said.
“We could try to bring the power in, but there’s a possibility we could get cut off,” Dasho said.
Large-scale projects using solar energy in Missouri are difficult because of the amount of solar energy received. Constructing utility-sized projects is not realistic, Dasho said, although projects could be effective on an individual basis.
Hydropower is also challenging due to a lack of possible hydroelectric sources. “Any hydropower in Missouri has already been bought,” Dasho said.
The definition of biomass would seem to be somewhat open-ended since technically all fossil fuels, such as coal and oil, are originally derived from plants. The city’s definition specifies that plants must be renewable within a 100-year time-frame to be considered biomass sources.
As a result, biomass sources that the city could consider using include landfill gas, paper-based products and wood or wood waste.
The city already has plans to convert methane gas, produced by decomposing garbage at the Municipal Landfill, into usable energy. The city could also consider turning cardboard and other paper products at the landfill into pellets that could be mixed with coal and burned in the power plant. Dasho said the city would first have to investigate whether the city plant could burn the pellets.
The Water and Light staff viewed conservation as a green resource that causes no additional pollution, Dasho said. “If we convince you to put in energy-efficient lighting, every year we get a renewable resource,” he said.
After discussion, the Environment and Energy Commission recommended that the city not include conservation in the definition of renewable energy.
Although practicing energy conservation is a good global rule, Spain said, conservation presented too many problems specifically related to meeting the terms of the ordinance.
“Someone may put in energy-efficient lighting, but then they may leave the lights on more,” Spain said. “There’s a problem figuring out exactly what is conserved.”
The issue of including conservation also faced opposition at a March 1 public presentation of future energy supply options. Win Colwell of the League of Women Voters said that including conservation would dilute the goals of the Renewable Energy Ordinance.
“Energy conservation and renewable energy should not be pitted against one another,” Colwell said. “Each is valuable in its own right.”
The city still plans to encourage customers to practice conservation because a reduction of energy use can save the city money, Dasho said.
Another source of green energy that could cause controversy is the use of “green tags,” or purchasing renewable energy credits for renewables used elsewhere. Dasho said the city would rather avoid this option.
“I find that a little disturbing,” he said. “I would prefer to bring green energy into the city.”