Innovation Breeds Innovation
Just upstream from the University of Iowa’s power plant is a wood-fired kiln that is utilized each semester by art students in the university’s ceramics program. This kiln, fired intermittently, is one the smallest of 456 individual emissions sources on campus. Still, the kiln carries an insignificant emission unit number and is identified in the university’s operating permit. In stark contrast, the power plant contains the largest of the 456 sources on campus. It generates more than 90 percent of the university’s annual emissions, and is a key element of the university’s ambitious sustainability and clean energy goals. “In 2010, our then-President Sally Mason and Karl Brooks, the U.S. EPA Region 7 administrator, developed and agreed to seven different sustainability targets for the university, the second of which was to obtain 40 percent of our energy from renewable sources by 2020,” says Ingrid Anderson, J.D., an environmental compliance specialist at the university.
The responsibility of meeting that goal in a cost-effective manner fell on the shoulders of the university’s facilities management team. “Our facilities folks looked at all of the options, and recognized that biomass was the most viable option because it didn’t require significant up-front capital requirements,” Anderson says. “We could use our existing assets and infrastructure and switch to a renewable fuel source, that being biomass.”
The university began searching for local, reliable sources of biomass waste streams, eventually focusing on oat hulls from a grain processing facility in nearby Cedar Rapids. At the same time, work began on the development of purpose-grown energy grass infrastructure in the local area. In order to cofire a growing percentage of biomass with coal at the power station, the university began committing time and resources to feedstock procurement, energy crop establishment and farmer recruitment. While the energy and innovation these critical efforts require are vital if the university is to achieve its goals, a less-celebrated, but no-less important permitting approach may ultimately be regarded as the project’s most important innovation.
Plantwide Applicability Limit
In March, the Iowa Department of Natural Resources issued the University of Iowa the state’s first Plant-wide Applicability Limit (PAL) permit. More accurately, the Iowa DNR issued the university seven PALs, one for each criteria pollutant. “That’s how a PAL is organized, one for each criteria pollutant,” says Sarah Piziali, supervisor of air quality construction permit program at the Iowa DNR. “So there is a PAL for each of three types of particulate matter (PM). There’s PM, PM10 and PM2.5 and then there are PALs for carbon monoxide, nitrogen oxide, sulfur dioxide and volatile organic compounds (VOCs).”
A PAL is an alternative permitting approach that provides entities with multiple emissions sources an increased flexibility across their emissions landscape when it comes to asset utilization, modification and fuel sources. PALs were made possible by some reforms to New Source Review provisions in the Clean Air Act in 2002. “There wasn’t a lot of flexibility built into those regulations, which is part of why, in 2002, they came out with these alternate regulatory approaches,” Anderson says. “Institutions needed more flexibility to try new things.”
Simply stated, a PAL moves an institution away from a source-by-source approach to emissions compliance, and toward a facility-wide approach, giving institutions flexibility that they would not otherwise have. Previously, if the university was going to add or modify emissions generating equipment, it would be required to complete prevention of significant deterioration (PSD) analysis. In other words, the university would have to determine if the new or changed emissions source would deteriorate the local air quality. This process is labor-intensive, can tax an institution’s busy facilities staff, and can also create some uncertainty around the emissions control equipment that will ultimately be required for the project. “The opportunity that we have with this PAL permit is that we take a facility-wide cap on emissions, and then because of that, the campus is considered to be in compliance with all of those PSD requirements,” Anderson says. “So now, we can do a project, we can modify or add equipment, and we don’t have the ambiguity of, ‘does PSD apply’ and what controls we might need to install to comply with those requirements.”
With a PAL permit, the university is free to manage all of its emissions sources as it sees fit, as long as it remains under the cap for each criteria pollutant. For example, the university’s facility-wide cap on carbon monoxide is 444.74 tons per year. If all of the sources together do not exceed this cap, the university is in compliance with that PAL. This flexibility is a perfect fit for the ongoing work at the power plant to increase the amount of biomass fuel that it uses, work that will likely result in biomass inclusion rates changing each year. Without a PAL, the power station would likely find itself in a nearly perpetual permit review process, bogging an effort the university is hoping to accelerate. “In the past, if the university wanted to include a new biomass fuel in its boilers, without the PALs, they would have to do a PSD analysis showing that this new fuel will not increase their emissions above the PSD significance levels for each criteria pollutant that they would emit,” Piziali explains. “And traditionally, carbon monoxide would be the pollutant that they were most concerned about. So they would have to show that the addition of this new fuel would not trigger a PSD requirement. Now that they have the PAL, they are allowed to increase their emissions from the boilers to whatever they need, as long as the overall emissions for that pollutant at the university do not exceed the cap set out in the PAL.”
The university is still required to meet emissions limits set forth in the National Ambient Air Quality Standards, Piziali adds, as well as the New Source Performance Standards and hazardous air pollutant standards.
This operational freedom does call for increased monitoring and tracking of monthly emissions, however. “This freedom to construct new or modify their existing equipment comes with the added responsibility and burden of having to track their emissions to a great detail,” Piziali says. “They weren’t having to do that before. They are getting some flexibility to shift their emissions allowances of the pieces of equipment that they’d like to modify or operate differently over the whole facility, but in exchange, they are to track what they are doing very closely.”
In order to make monthly emissions tracking more feasible, the university uses emissions factors and worst-case scenarios on a sizeable number of the emissions sources at the university. “Consider the wood-fired kiln at the art school,” Anderson says. “We had to go with a worst-case scenario for that source, because putting in some sort of monitoring apparatus in the kiln just wasn’t feasible. We worked hard, in collaboration with staff from the Iowa DNR, with one-off situations like that to make sure that we were protective of our environmental quality, while also arriving at a workable way to account for those emissions.” Because the vast majority of the university’s emissions emanate from the power plant, those emissions will be monitored very closely.
To meet the ambitious goals the university established for itself—40 percent renewable energy by 2020—the inclusion of biomass will have to more than double from current inclusion rates. “In 2015, we were at 15 percent renewable, and I’d say all of that was from biomass cofiring,” Anderson says. In 2016, she expects to see inclusion rates closer to 20 percent. “I always tell people that this isn’t a linear progression,” she says. “A lot of the groundwork we’re laying now should allow us to ramp up significantly in the last few years before 2020. We’re doing some really innovative stuff with biomass, and this permit was another innovative solution to remove some hurdles and to pave the way to increased biomass usage on campus. Innovation breeds innovation, that’s how I like to look at it.”
Whether the university is ultimately able to grow its biomass inclusion rate to 40 percent in less than four years remains to be seen. However, with the issuance of the PAL, its air permit will not be the bottleneck in its efforts. The permit, valid until 2026, provides the university the flexibility to ramp up its biomass inclusion well beyond the goals set forth in 2010. “Our hope is to keep increasing the percentage of biomass as much as possible,” Anderson says. “We’re not interested in hitting 40 percent and then staying there. We want to keep working toward as much biomass as possible.”
Author: Tim Portz
Executive Editor, Biomass Magazine