Biomass plant operational, overcomes some anticipated bumps
Representatives of the new Biomass Heating System at the Health and Human Services Building, also known as the county annex, presented a report on the progress of the new operation at the Tuesday, Jan. 15, meeting of the Board of Supervisors.
Jonathan Kusel, executive director for Sierra Institute for Community and Environment, based in Taylorsville, and Camille Swezy, the biomass program associate for the institute, also dispelled rumors concerning the new system.
The biomass plant is still in its early operating stages and is the result of a $2.6 million California Energy Commission grant, plus a $100,000 national competition award. When the wood-fired plant is fully up and running it will be turned over to Plumas County for full operation.
It is designed to use wood chips to heat the neighboring county facility.
“It’s brand new and it only knows what we teach it,” said Kevin Correira, Plumas County Facilities Services director. Correira has been involved on the county side of the operation. Information for the operation comes from a company in Austria and its representatives are due to visit soon.
The biomass system is a three-megawatt facility that produces both heat and electricity.
“It’s been a few years,” Kusel told the board explaining the length of time since he was before the board.
He said there have been a few bumps in the development of the system, but he considers them relatively minor considering the complexities of the system and getting the kind of fuel they need for the design.
Biomass presentation
“The full biomass heating system, including the backup propane boiler, power generator, and all system controls, were fully connected and commissioned shortly following the ribbon cutting ceremony in April of 2018,” Swezy told the board.
Sierra Institute, along with High Sierra Community Energy, spent six months learning about fuel storage, handling and hauling logistics. They’ve also been involved with training county staff in the boiler operations and management as well as monitoring how the system runs in varying operating scenarios. These determine how to effectively maximize system efficiency and cost savings for the county, Swezy explained.
“The development team, along with Plumas County Facilities, have been working to ensure adequate heat is provided to employees in the Health and Human Services Center since October of 2018,” Swezy said.
Getting the entire automated biomass system completely commissioned takes time, Swezy said. It also has its challenges. “The boiler, power generator, backup propane boiler and piping are functioning as expected with no major issues,” she said. “We have provided heat as per the Thermal Energy Services Agreement between Sierra Institute and Plumas County throughout this time, but there have been some kinks that we’ve had to work through.”
One of the problems the team encountered centered on fuel. An initial load of fuel proved to be too wet for the system, Swezy said. Although that same fuel works well in the biomass operation at Sierra Pacific Industries, the new system encountered issues. “The primary issue encountered to date involved the fuel bins and ram feed that push fuel from storage into the boiler,” Swezy explained.
Unfortunately, a lot of smoke was produced when the system experienced the initial problem with wet fuels, Swezy said. What they did to relieve the problem was to shut the doors to the operation and attempt to contain it within the operation.
While the problem is fixed, Swezy and Correira explained that wet fuel doesn’t work well when initially firing up the boiler. It can be used once the facility is fired up and operational, they’ve learned. “As of January 3rd, a solution was developed and implemented and the system has operated smoothly since,” Swezy said.
Correira said that for the two weeks the facility was providing heat to the annex that building’s electric bill came down significantly. He said the building’s bill is traditionally $10,000 to $11,000 a month and he saw a drop in costs. However, Correira didn’t have the savings amount with him and couldn’t be reached by press time to supply that amount.
There was an additional setback when the plant experienced a power outage related to the Camp Fire incident in early November, Swezy explained. While the system does have one type of generator, a second one to use as a backup system when the power goes out is being considered. High Sierra Community Energy and Wisewood are helping identify a backup generator system and it is expected sometime this year.
Fuel supply
Swezy has been working on making contacts for fuels for the plant. She told the board that Sierra Institute enlisted the help of Toppers Tree Service in Quincy last July. They are working to help with hauling fuel to the operation. “By November, Dave Sims of Toppers Tree Service successfully built a roll-off truck capable of hauling the fuel bins to the boiler building,” near the annex location, Swezy explained.
She said that he has agreed to serve as the primary fuel hauler for the operation.
Waste Management, the main garbage collection business, was the only local entity with a roll-off truck compatible with the system’s fuel bins, Swezy said. And while they were extremely helpful in the early phases of the project, management expressed numerous liability concerns and wasn’t interested in a long-term contract. “Dave has been delivering wood chips to the site successfully since November, and has been helping with boiler operations needs on an on-call basis under Sierra Institute ownership,” Swezy said.
Crescent Mills operation
As part of the biomass project, a wood chip process operation in Crescent Mills is being arranged and is expected to be set up in the spring, Swezy said.
While Toppers Tree Service is a primary fuel storage site and supplier, the Crescent Mills operation will handle additional supply contracts as established.
As part of the project, a wood chip processing operation will be capable of providing clean chips for the boiler operation in the county. “Clean, even sized chips allow more for efficient, cleaner combustion,” Swezy added.
Sierra Institute, through Swezy’s efforts, is working to secure fuels from fuel reduction projects by the Fire Safe Council and the Plumas National Forest starting this summer. This further promotes the benefit to communities through the biomass effort.
Additional sources of fuels include logging contractors and many have express an interest in delivering chips, Swezy explained, as well as fuel from Sierra Pacific Industries in Quincy.
Timeline
June 2018, Kohlbach and Wisewood ensured that all components were properly connected and functioning. The system’s automatic mode was set up and the control panel was working as designed.
That month, two loads of wood chips were obtained from SPI to start up the boiler. Swezy said they asked for clean chips, but an internal miscommunication at the mill resulted in the delivery of wet, heavy loads of chips. These damaged the hydraulics at the base of the fuel bins and caused the smoke some noted. “Dry material is needed for system startup,” Swezy said they learned from that experience.
She added, “SPI apologized for the error (and) allowed Sierra Institute to return the material and reimbursed us for the order.”
In July 2018, facilities operators concentrated on repairing the damage done to the hydraulics.
By September they were doing a full system firing with both the boiler and power generator and were monitoring operations and working through emerging issues, according to Swezy’s timeline.
That month they were also doing some welding modifications and height expansion to the ram feed. They needed to prevent fuel with pine needles from jamming the system. “It was noted that fuel easily jammed when larger pieces are present,” she said.
Last September also saw high temperatures so the operation was only needed a few hours to provide heat each day. Swezy said they decided to leave the boiler off until November when the annex’s heat demand increased. At the time the propane boiler was used to supply heat.
By the first week in November High Sierra Community Energy and Wisewood trained staff. This training was on the system startup process and operations management. This was cut short when the power outage caused by the Camp Fire occurred. “The boiler stayed off until the following week,” Swezy explained.
Later that month the full system was fired up for three days and various operating capacities were tried. These included heat production only and the power production only for heat and power processes.
“The system operated successfully during this time,” according to Swezy’s report. “Some control panel programming was needed and was performed by Kohlbach, the boiler manufacturer, whose staff traveled to Quincy to do the work.”
They also experienced some breakers that kept tripping and causing the boiler to turn off. An electrician was hired and fixed the problem.
Later in November, Swezy said that they experienced more issues. The stoker overfilled and then the system shut off. “Because this scenario could damage equipment and is unsafe, the project team decided to prevent the bins from operating until the issue could be solved by Kohlbach, the manufacturers of the boiler and ram feed,” she said.
And then the technician from the company wasn’t available until December, she added. To manage this delay, Sierra Institute decided to use the propane boiler to heat the annex.
In December, the installation of the temperature sensors and their compatibility with the BRU meter allowed the operation to accurately track the number of BTUs provided to the annex, Swezy said.
The new sensors prevent it from overfilling the fuel into the stokers. High Sierra Community Energy/Wisewood and Kohlbach technicians performed this process. “We quickly learned that these new sensors were still inadequate to accurately detect material causing a large amount of wood chips to spill overnight,” she said.
The hydraulic floors of the fuel bins were also rebuilt and reinforced in December.
Technicians returned to the operation this month to correct the sensor problem. A light barrier sensor was installed as the primary control for the fuel feed. Two additional backup sensors were also added for redundancy. These are an ultrasonic sensor and a sensor signaling if the bin has moved.
Full operations including heat and power generation have been working as anticipated, she said.
The next phase of the process involves data collection, something that some Supervisors expressed keen interest in getting. And the system will be monitored to achieve the highest efficacies and cost savings. Swezy said they would continue to share their information with the board this spring as they learn more.
Conclusion and rumors
At the end of the presentation Kusel told Supervisors “We’ve learned a lot in this process.”
“What’s really fun is that we’ve been asked to do presentations,” to other interested groups. “This is a novel system.”
Kusel said that the system is getting a lot of attention from people. He said that the Plumas County Sheriff’s Office is interested in possibly adding a system to the new jail design. And the school district is interested.
Kusel said that the system does cut costs. There have been kinks in the system, but that’s to be anticipated in new technology.
Correira said there have been rumors surrounding the new operation. One rumor said that the system was only to run on pellets — the kind generally associated with pellet stoves. And that’s just not the case.
Swezy said, “Rumors are going to happen.”
Speaking from the audience, Assistant Planning Director Joe Blackwell asked about air quality. He said his department is interested in obtaining grants because the county has good air quality. He said he didn’t want to see problems with the biomass operation producing air quality problems. Blackwell was assured that the smoke produced during a malfunction wasn’t a regular occurrence.
Supervisor Lori Simpson was riled that Supervisors weren’t notified that the biomass operation was taken offline in part of December. “I don’t want to see that happen again,” Simpson said.
Correira responded with “I can take the blame on that.” He said he didn’t realize the Supervisors were “so vested” in the process. He said he would keep them informed of things.
Supervisor Michael Sanchez was one of the supervisors who voiced concerns about the lack of data so far. Swezy said they needed a baseline to use when compiling data. Also, the biomass operation hasn’t been online long enough to provide much data. She did say she understands the importance of data and it will be forthcoming.
