With five years of experience operating a combined heat and power system fueled with biogas, Fort Wayne City Utilities is ready to make more progress toward net-zero energy by 2030.

That was the goal set in 2017, and the success of the CHP system has given the wastewater treatment plant staff confidence that they can reach the goal.

“The CHP has worked remarkably well, better than expected,” says Doug Fasick, engineering manager for energy for the Indiana utility. “The plant staff has championed this. They’ve taken ownership of it and they make sure that it is maintained properly to keep it up and running. Now we’re looking at enhancing our biogas production by taking in additional organic waste.”

The first source of outside organic material was a Nestle processing plant in nearby Anderson that makes CoffeeMate creamer. Since 2018 the wastewater plant has received up to four 6,000-gallon truckloads of food waste every day from that facility.

“It’s basically fats, oil and grease (FOG), and we feed it to the bugs in our digesters,” Fasick says. “We’re a 100 mgd plant (peak), so 24,000 gallons is a very small percentage. We have significant capacity to do more.” In 2020, the utility acquired more digester feed by signing a contract with quasar, an organic waste broker.

Organizing a co-op

The COVID-19 pandemic, which has crippled the restaurant business, has slowed some of the utility’s other plans to put more organic material in the six anaerobic digesters. An example is a co-op program designed to boost the supply FOG.

“Right now, it is the responsibility of the restaurant owners to dispose of their FOG,” Fasick says. “The co-op is a voluntary program that gives them another way to manage their FOG. They pay us a membership fee; we hire a third party to clean out their grease interceptor on a scheduled basis. It helps the waste haulers because they get what we would call a milk run.” 

Septic haulers that handle grease have other options for handling FOG, but Fasick hopes that by making grease management easier for both the restaurants and the haulers, the co-op will make the treatment plant more competitive in the market.

“There are other facilities that can handle FOG; waste haulers do have a choice,” Fasick says. “We’re hoping to get 100 restaurants signed up as part of the pilot program, and then we’ll be able to offer reduced prices. We want all that waste to come to us.”

Feeding the bugs

Fort Wayne is also looking to get more solid food waste from restaurants and grocery stores, which would then be macerated to feed the digesters. It’s lower in energy than FOG, but the microbes in the digesters need variety in their diet.

“You have to take into account the bugs,” Fasick says. “You don’t want to feed them the same thing all the time. You want to give them variety. It’s like giving a kid candy. If that’s all you give them, that’s all they’ll eat. You’ve got to balance it to maintain good health. And it fills a need for the community. We’re diverting the organic waste from a landfill.”

The methane production at the wastewater treatment plant was one factor in Fort Wayne winning a 2019 Sustainable Water Utility Management Award from the Association of Municipal Water Agencies. But the wastewater plant has potential for many other energy projects. 

“We’re looking at our property for opportunities to install solar components to help us generate energy,” Fasick says. “There’s going to be a request for proposals for energy companies to help us determine what makes the most economic sense from biogas, from solar, and from wind possibly. We’re also looking to optimize our operations in the plant, so we’re using our assets the best we can, always with the premise that we’re trying to keep our rates low and making sure we’re competitive for economic development.”

Long history, ambitious goal

Fort Wayne would probably get high marks for sustainable operations on any scale. Since 2001, the wastewater plant has been producing Class A biosolids that get mixed with composted leaves collected by the city. The soil supplement is given away to residents and sold to landscapers and farmers.

Dewatered lime from the water plant is also sold to farmers. Since 2017 the plant has reduced its electricity usage by about 5% by replacing low-efficiency motors and lightbulbs, adding variable-frequency drives to motors, and upgrading some processes. The energy produced by the CHP system has replaced about 30% of the plant’s consumption.

Still, the staff is in a constant battle with energy costs. “Since 1992, the utility has seen electricity costs go up almost 100%,” Fasick says. “At one point several years ago, it was just the nature of doing business. You couldn’t control it; you just had to cost it into your rate base.

“That’s no longer the case. There are opportunities from a renewable standpoint and looking at operations. We started putting some of these things in little by little, learning from them, and seeing the benefits they bring.” In five years the team has reduced utility energy consumption by $2.2 million and has produced more than 32 million kWh of electricity.

Fasick believes the goal of becoming a net-zero utility by 2030 is achievable: “It’s an ambitious goal, but so far we’ve been fairly successful.”