California Craft Beers and Biogas Bargains
When ordering a frosty mug of their craft beer, consumers might enjoy its citrusy notes, the robust, roasted taste of a stout, or the bitterness of a signature hop blend. For some, the experience may be even more enjoyable knowing their favorite brewers are utilizing biogas technology to save on their operational costs, address water management issues and become sustainability leaders within their communities.
Although anaerobic technology has already been embraced by larger brewers such as Anheuser-Busch, the smaller players are beginning to adopt that trend. “We are seeing more of the craft brewers starting to look toward putting in an anaerobic system, rather than pay surcharges or installing an aerobic system,” says Denise Johnston, vice president commercial at Biothane LLC. Biothane’s upflow anaerobic sludge blanket (UASB) and Biobed expanded granular sludge blanket (EGSB) technologies have been implemented in approximately 100 wastewater treatment operations located at both large and small beer breweries around the world.
“As our members grow in size, they have been looking for ways to increase their bottom line and become better stewards and citizens in their communities,” says Chris Swersey, technical brewing projects manager at the Brewers Association. By identifying with their communities, sustainability efforts have generally become more important within recent years, he adds. Within the group of craft brewers that are large enough to capitalize biogas projects, the technology has caught the interest of other members reaching that threshold. “Within the whole subset of sustainability efforts, biogas is starting to become an option for some craft brewers,” Swersey adds. “Not for a large number yet, but enough where we are starting to pay attention to it as an association.”
Harnessing power from biogas has the potential to help one of the fastest-growing sectors in the U.S. address sustainability objectives in energy consumption, solid waste and wastewater treatment. According to the U.S. EPA, 70 percent of all U.S. brewers’ electricity consumption is for refrigeration, packaging and compressed air generation. Plus, U.S. breweries use an average 12 to 22 kilowatt hours to produce one barrel of beer.
A brewhouse’s heating operation accounts for roughly 45 percent of all U.S. breweries’ natural gas and coal consumption, and takes 1.3 to 1.5 therms, or 130,000 to 150,100 Btu, to produce a barrel of beer, according to Brewers Association data. Smaller breweries tend to have higher kilowatt-hour-to-barrel numbers since smaller volumes cannot make up for the base energy requirements for a barrel of beer.
Although energy consumption is one of the big issues facing the craft brewing industry, the greatest is water usage, Swersey says. The amount of water to brew a barrel of beer varies from each location, brewing processes and types of beer, and, on average, it can take roughly seven barrels of water for every barrel of beer. The majority of breweries discharge 70 percent of this incoming water through its effluent waste stream.
AD technology helps breweries address wastewater objectives while generating a fuel from organic compounds for thermal or electrical power. In addition to biogas production, anaerobic pretreatment has lower operating costs, a smaller footprint and costs roughly the same, or sometimes less, than aerobic technologies, according to the Brewers Association. A 50-kiloliter UASB reactor is the smallest, entry-level AD system a brewery can use. Additionally, the 50 kiloliter unit is sized for breweries that annually produce 118,000 to 236,000 barrels of beer, and has an estimated installed cost of $700,000 to $1.2 million.
In addition to capital costs, available space is weighed in the decision of anaerobic versus aerobic. “Nobody has a lot of free space, but some brewers are more space constrained than others,” Swersey says. “If you have a very limited footprint, you’re likely going to go with anaerobic even though it might cost you a little more than to go aerobic, because space is the limiting resource there. So a lot of our members may have grown really fast into the space they have, and they just don’t have a lot of open area on their facility.”
Drought-stricken regions add extra pressure on breweries to conserve water and wastewater processing. “Particularly in California, water is an issue. We are in a drought year currently, and that is being talked about a lot,” says Tom McCormick, executive director of California Craft Brewers Association. “We know that in future years, water will be a rare commodity here in California, and it’s just best business practices for everyone to begin thinking about how to use less water.”
“As these breweries, especially in California, continue to expand and grow, it’s increasingly adding pressure on their local, wastewater treatment infrastructure,” says Cheri Chastain, sustainability manager at Sierra Nevada Brewing Company. “When breweries are looking to site a new facility or an expansion, they are often hit with these high wastewater fees that they weren’t expecting because it isn’t something that immediately comes to people’s minds. Anaerobic digestion is one way to help offset that cost because you can recover the initial capital investment a lot quicker by using the biogas.”
Although anaerobic technology addresses wastewater issues, brewers may be unsure when to start thinking about implementing the technology. The Brewers Association suggests craft brewers, that produce 150,000 to 300,000 annual barrels of beer, should begin considering advanced wastewater pretreatment technology when annual sewer discharge costs reach $250,000 or more.
Revamping Current Systems
To address its growing pains, the Sierra Nevada Brewery in Chico, Calif., looked toward anaerobic and aerobic technology to clean up wastewater and take pressure off the local waste water treatment infrastructure. “The municipality got to a point where they couldn’t handle the loading anymore,” Chastain says. “So either we had to install the system and handle the load here or pay additional money to the municipality to upgrade their system.”
In 2002, the brewery constructed its waste water treatment facility with Biothane’s 132,000-gallon UASB anaerobic digestion technology to treat outgoing effluent and capture biogas. More than 95 percent of the captured biogas is used to fuel the brewhouse boilers, Chastain says. “We’re capable of producing and using up to 70 standard cubic feet of biogas per minute.”
After being treated by the UASB, the wastewater is further processed by the facility’s conventional activated sludge system, Johnston explains. According to Sierra Nevada’s 2012 sustainability report, the brewery’s wastewater becomes comparable to the effluent water from residential zones at the end of the treatment process.
In 2005, the brewery installed hydrogen fuel cells, which are powered by natural gas, and is capable of generating up to 1 MW of electricity. The brewery currently does not use biogas to fuel the fuel cells because the current cleaning skid lacks the design to pipe the biogas into the fuel cells, Chastain explains. “There was no storage for gas. It just comes straight off the digester into the cleanup skid and right into the use point,” she adds. “There wasn’t any storage either pre- or post-cleanup, and that would create a variable pressure going into the fuel cells, which don’t handle that [variable pressure] well.”
The brewery’s fuel cell contract expires within a year, and the company is investigating other ways to enhance its biogas usage. “After a year, the fuel cells will be coming out,” Chastain says. “So we are looking at replacement technologies, what we can replace the fuel cells with, and hopefully we can better use our biogas to generate electricity.”
As more craft breweries come on line and become thriving businesses, brewers will look toward technology producers to build their standing within their community and make the entire process more efficient. “I know there is a lot of interest out there, and there surely is a lot of potential,” Swersey says. “We’re going to hit 3,000 breweries in the U.S. this year. When that happens, they all start small and they grow. As those breweries hit a certain size, they’re going to need to take steps to maximize their efficiency and control their costs and to control their resource consumption as much as possible. Biogas is just one tool of many in the potential toolbox.”
“We’re not seeing any major obstacles to implement the technology,” Johnston adds. “There’s certainly some permitting they have to go through. From a regulatory standpoint, even if they plan to use all the generated biogas, you still must have a flare, which needs to be permitted. So there are some permitting requirements, but again, all of our systems have been permitted without any delays or problems.”
Author: Chris Hanson
Staff Writer, Biomass Magazine