Food Engineering

Sustainable Plant of the Year: Sierra Nevada Brewing Co.

September 1, 2009
An interest in shrinking the plant’s carbon footprint and a good neighbor attitude help ease hurdle rates for sustainability initiatives at this California craft brewery.

Sundown signals quitting time for Sierra Nevada’s rooftop solar array. Solar delivered 247,263 kWh of electricity in June.  Source: Bill Manley, Sierra Nevada Brewing Co.


Wastewater samples are drawn from the brewery’s treatment plant. Anaerobic digesters are housed to the right, with aerobic treatment and final filtration to the left. Source: Bill Manley, Sierra Nevada Brewing Co.

The term “craft beer” hadn’t been coined 30 years ago when a smattering of entrepreneurs, many of them former home brewers, turned their passion into a profession and launched the first microbreweries.

Reuse of materials, minimization of waste, equipment innovation-resourcefulness and thrift were essential if they were to have any chance at commercial success. Most didn’t make it, but a few survived and thrived in what is now a $6.3 billion segment of the American beer market. Their early practices dovetail with the goals of sustainable manufacturing, and some are grabbing the lead in greenhouse gas reduction and renewable energy generation.

Ken Grossman was in the first wave of craft brewers. A former partner and he started Sierra Nevada Brewing Co. (SNBC) in Chico, CA in 1980, cobbling together used dairy equipment and packaging machines to make a distinctly hoppy beer for regional consumption. “Our early years of frugality and forced innovation gave us no choice but to be efficient,” he remembers. Today, SNBC’s beers are distributed nationwide. The Brewers Association ranks SNBC as the nation’s second largest craft brewery, with 2008 production of 669,784 barrels-the equivalent of 36.9 million six-packs. Volume grew 150 percent in the last 12 years.

Business success made Grossman a wealthy man. It also gave him the financial wherewithal to invest in high-profile renewable energy projects, which SNBC has done. But the core principles to renew, reuse and recycle permeate every production step and business practice. This comprehensive approach earned SNBC Food Engineering’s Sustainable Plant of the Year designation.

With solar panels filling in the last few bits of open rooftop this summer, the brewery now boasts a solar array exceeding 10,000 panels. During June’s long, sun-kissed days in California’s Central Valley, solar delivered 247,263 kWh of electricity, reports Cheri Chastain, SNBC’s sustainability coordinator. Another 678,266 kWh came from an on-site fuel cell stack. Operating the brewery, its brewpub, restaurant and ancillary buildings required almost 1.1 MWh, leaving the operation 159,072 kWh short of the goal of being completely off the grid.

The fuel cells are the plant’s green-power workhorses. The four 300 kW cells from FuelCell Energy Inc. of Danbury, CT, netted SNBC the Governor’s Environmental and Economic Leadership Award in 2005. In the dead of winter, they meet almost 90 percent of the plant’s electrical demand, and solar fills the rest. The cells are powered by natural gas, with waste heat captured and converted to steam for the brewing process. Water and CO2 are exhausted, and there are no transmission losses or carbon emissions, as would be the case if the electricity came from a distant, coal-fired utility plant.

Ambitious initiatives like fuel cells and solar arrays became feasible when production reached a critical mass. “A small brewery can’t install fuel cells because they require a fairly stable energy load and round-the-clock production,” Grossman points out. Thanks to booming sales, “today we’ve got more money so we can put in larger capital projects that have longer paybacks.” Another example is the CO2 recovery system commissioned in 2005.

Carbon dioxide is a byproduct of the fermentation process, and most brewers that produce 2 million barrels-plus have recovery systems that wash out the ethanol, organics and noncondensable gases before liquefying and storing the CO2. Dan Gruber, CO2 technical manager for Rockford, IL-based Norit Haffmans NA, recalls discussing the technology with Grossman as early as 1993. Recovery systems aren’t economically feasible for small breweries, but Gruber and Grossman kept crunching the numbers as production volume grew.

Once a five-year return came into view, SNBC began using recovered CO2 for carbonation at bottle filling, keg pressurization and counterpressure in holding tanks. The purity is food-grade and has turned the brewery from a buyer of the gas into a supplier. Sustainability is a continuous improvement journey, and SNBC ownership now is eyeing a heat-recovery system that would eliminate the need for refrigeration by using stored liquid CO2 to condense incoming vapors. The economics are attractive, but that’s icing on the cake for SNBC, Gruber maintains. “Ken did this for several reasons: first, to be environmentally friendly, and second, to be a good neighbor,” he says. “A reasonable return ranked third.”

Pedal power propels visitors touring Sierra Nevada Brewing’s facility in Chico, CA. In the background is the brewery’s hop field. A canopy of solar panels shades parked cars from the Central Valley sun. Source: Bill Manley, Sierra Nevada Brewing Co.

Meat & potatoes projects

Breweries worldwide routinely recycle spent grain for animal feed. SNBC takes the practice to its closed loop conclusion: Through a cooperative program with California State University-Chico, SNBC’s grain helps feed 60 head of cattle raised by UC-Chico ag students. Post-harvesting, the beef ends up on dinner plates in the brewery’s restaurant and taproom.

This spring, 26 acres of barley planted a mile from the brewery were harvested. It will be malted and combined with fresh hops grown on nine acres next to the brewery. “It would be way too challenging to do everything with locally sourced raw materials,” Grossman concedes, but autumn’s debut of a limited edition brew called Chico Estate Harvest Ale is the brewery’s salute to the ideals of locally grown, locally processed food.

Hops grow best in a cool, damp climate, which is why the Pacific Northwest has emerged as one of the premiere hop-producing regions in the world. Growing hops under the scorching Central Valley sun demands large amounts of water, a resource SNBC is committed to conserving. Beginning in July, as many as 5 million gallons of treated and filtered water that used to flow to municipal treatment plant began to trickle into the adjacent hop field. Because organic certification is being sought, the field requires manual weeding and tending. SNBC staffers pick up extra hours by tackling those jobs.

Recycling efforts also can be tedious, and California doesn’t make it easier. Until recently, staffers were required to bundle and tape old batteries to satisfy a state toxic-substances rule. “People were having taping parties at the landfill,” groans Chastain. Separating paper, plastics by grade and other materials is similarly time consuming, but the payback is both environmental and financial. Only 306 tons of waste, mostly restaurant food scraps and miscellaneous plastics, went to landfill last year, Chastain says. More than 68,000 tons were diverted, saving the company $4.7 million in disposal charges.

Creative reuses help make a successful diversion program. A barter deal was struck with local beekeepers, who trade honey for the burlap sacks used to ship hops to the brewery. The boxes in which bottle crowns arrive are flattened and sent to a supplier for the next order of SNBC tee-shirts. (Merchandising is a big part of craft brewing’s business model.)

Efforts to boost energy- and resource-efficiency have a long track record. Heating coils replaced steam jacketing on the wort kettles a decade ago. More recently, boilers were retrofitted with online oxygen sensors and variable-speed blowers to increase efficiency and minimize emissions. T-5 and T-8 fluorescent lights on motion sensors are found throughout production areas. New warehouse and office space completed last year makes use of natural lighting, and salvageable windows, light ballasts and other building materials were donated to Habitat for Humanity for recycling. Thick concrete tip-up walls were used to eliminate the need to heat or cool those structures.

Heat exchangers and VFDs on motors and compressors are in abundance in the brewery. Those are efficiencies Grossman has sought from the outset, when ice for production was made at night, and electric rates were low. Often, he was deploying technology that wasn’t ready for industrial prime time.

“When we first put in frequency drives 20 years ago, they were super expensive and not very reliable,” Grossman relates. Today’s drives are relatively inexpensive and much more robust. They also lower maintenance, thereby lowering workplace stress. The human effect of technology must balance technical efficiency: High-pressure sodium lighting is very efficient, but workers must contend with poor color, which drove SNBC to switch to high-efficiency fluorescent ballasts.

Some projects fall into the conversation-piece category, though they also speak to the company’s values and culture. The electricity from the three acres of solar panels that blanket the staff parking lot feed two electric-vehicle charging stations. Employees, visitors and neighbors are free to use them, at no cost. To date, no employee, visitor, or passerby has used either of the two electric-vehicle charging stations, despite the attractively low price.

An event trailer equipped with tappers has been outfitted with solar panels to help refrigerate beer kegs. Used fryer grease from the restaurant is dumped into a biodiesel processor that takes two days to complete a 50-gallon batch.

In April, the first diesel-electric hybrid tractor sold by Peterbilt Motors Co. was delivered. The tractor is dedicated to local delivery routes to maximize the mileage boost from the electric motor.

Public tours of the brewery are everyday occurrences. For beer distributors and other honored guests, a grander behind-the-scenes look is provided in what is officially known as the touring bicycle but more commonly referred to as the bar cycle. Built on a BMW chassis and equipped with a three-speed International Harvester transmission, the bar-on-wheels is pedal-powered by passengers seated at a dozen barstools flanking the driver in front and beer kegs in the back. When the touring bike swings into public view, shouts of “awesome” rain down.

Chico is a bike-friendly college town, and many SNBC employees are alumni. Instead of pedaling to class, the company encourages them to pedal to work or on short errands to lower their personal carbon footprints. Of the 490 SNBC staffers, 90 participate in the Green Machine bike program, Chastain estimates.

Hydrogen fuel cells are the workhorses in on-site electricity generation. Four 300-kW batteries supplied almost 800,000 kWh in March. Source: Bill Manley, Sierra Nevada Brewing Co.

Business of brewing

Grossman maintains his original devotion to hops and attachment to dairy equipment. The dairy tanks that held fermenting brew in the original brewery didn’t make the transition to the current facility, built in 1989 and doubled in 1998. But flowverters, the precursors to mix-proof valves in dairies, can be seen throughout the facility, and the nameplates of Fristam on pumps, Alfa Laval on heat exchangers and Mueller on tanks are everywhere.

Bitterness in beer was unknown to most Americans 30 years ago, and Sierra Nevada Pale Ale was a new sensation. Many of them liked it, so much in fact that microbrewers and craft brewers have been ratcheting up the bitterness units ever since. Pale Ale is almost a middle-of-the-pack craft brew in this regard now, and SNBC has responded by upping the ante on its newer styles.

One of SNBC’s newest offerings is Torpedo, a highly hopped ale. Introduced in the spring, Torpedo’s popularity caught the company by surprise, setting off a scramble to fill orders. The beer borrows its name from a torpedo-shaped vessel fabricated by DCI Inc., a St. Cloud, MN, dairy-equipment supplier. The vessel is packed with hops and placed in line for an additional dousing when beer is piped from the holding tanks.

Microbiological testing is another dairy practice Grossman has retained since the early days. The QA lab now goes well beyond bacterial tests to a wide range of chemical analyses, with mass-spectrometry analyzers and high-performance chromatography equipment available. The CIP system runs between batches, aiding sanitation-but contributing to the plant’s wastewater stream.

By the late 1990s, Grossman recognized the need to address the effluent issue. Municipal treatment rates had more than tripled, discharge was increasing in parallel with production growth, and the need for a pretreatment system was apparent. “We weren’t forced into it, but I could see the writing on the wall,” he says. As one of the city’s largest wastewater generators, the brewery either had to build its own treatment plant or expect to help finance expansion of the municipal facility. An upflow anaerobic sludge blanker digester backed by an aerobic system came on line in 2002. The digester’s methane was flared until a few years ago, when it started to feed the plant’s boilers. More treatment upgrades have followed, the most recent being final filtration of suspended solids prior to hop-field irrigation.

Anheuser-Busch started compressing and filtering methane-rich biogas from anaerobic digesters at about the same time SNBC was starting out, though that doesn’t necessarily mean SNBC is late to the game. Two years after SNBC began using its biogas to fire boilers, A-B’s 6 million-plus barrel brewery in nearby Fairfield, CA, became the 10th plant in its system to reuse digester methane; two A-B breweries continue to flare the gas. And SNBC was the first brewery to attempt using digester methane to power fuel cells.

Unfortunately, gaps remain between what is technically feasible and what is doable. The supply of biogas is variable, depending on brewery throughput and atmospheric conditions. Biogas must be blended with natural gas, and the blend is constantly changing. The controls technology delivered by FuelCell Energy wasn’t up to the challenge, and the effort was suspended in the spring. The fuel cells now are running entirely by natural gas, with the biogas rerouted to boiler use.

It was neither the first or not likely last sustainability setback. Hydrogen batteries for lift trucks were demonstrated unsuccessfully a few years ago. Technology to turn spent yeast into plastic was too immature, despite SNBC funding of university-level development work. Undeterred, the brewery is working with E-Fuel Corp. of Los Gatos, CA to recover ethanol from the 1.6 million gallons of inactive yeast it generates each year.

Water conservation is a priority for most beverage manufacturers. In the last 21 months, SNBC cut water consumption per unit of production by a third. Restaurant operations work against conservation efforts, skewing the ratio of gallons consumer to finished goods, though SNBC’s 5.1:1 ratio is in line with industry averages. Water and electricity are consumed when stripping out alcohol in the CO2 recovery system. The biofuel processor consumes 45 gallons of fresh water for each 50-gallon batch it produces, though managers hope to switch over to the purified wastewater for this. But resource tradeoffs are inevitable in sustainability efforts. In the end, “do what you think is best” is the guiding principle, according to Grossman.

In craft brewing circles, “Ken’s the technical go-to guy,” says Paul Gatza, director for the Brewers Association, a Boulder, CO, trade group. As president and sole owner, Grossman doesn’t require board approval to undertake a project. Nonetheless, hundreds of workers and their families depend on him to operate a sustainable business. “I have a sliding scale for the ROI,” he explains, “and if it’s something that I really believe in, I’ll accept a return that would normally be considered a poor economic investment.” In the end, however, environmentalism must coexist with capitalism.

Grossman is uncertain if the goal of carbon neutrality is ever possible for a manufacturer, and he frets that efforts to reduce greenhouse gas emissions might devolve into a marketing ploy. But he perceives growing public awareness of the environment and a mindshift change among many manufacturers. And while voluntary participation in greenhouse gas reporting programs like the Climate Registry and numerous awards from waste reduction groups are good for SNBC’s image, the main motivation is to do the right thing and to encourage the SNBC community to do likewise.

“People should drink our product because it’s a high-quality beer,” Chastain emphatically states, not because of the brewery’s sustainability efforts. Success in pollution and carbon reduction will, however, be quietly toasted in house.

For more information:
Glen Lewis, Lewis Energy & Technology Systems, 916-361-6540, glen.lewis@glenlewisgroup.com
Dan Gruber, Norit Haffmans, 386-852-4951, dgruber@haffmans.na.com

Transportation Manager Stan Cooper watches as Canadian barley is unloaded at the brewery’s rail spur. Besides enhancing supply-chain efficiency, rail delivery keeps thousands of tractor-trailers off the highway each year, reducing greenhouse gas emissions. Source: Bill Manley, Sierra Nevada Brewing Co.

Energy portfolio management

Behavior change is a linchpin in effective sustainability programs, and providing workers with real-time information from an energy management system is an effective way to change behavior: a solar array at a Pepsico distribution center in Fullerton, CA performed 10 percent above design, thanks to the decisions made by operators armed with real-time utilities data, the division’s sustainability and technology chief reports.

Sierra Nevada Brewing hopes for similarly positive results with Green Energy Management System (GEMS), a program that reports CO2 and carbon emissions as well as the economic costs of water, air, gas, electric and steam generation. More than a dozen meters were being installed at the Chico brewery in July in preparation of the system’s rollout.

Modified from a Square D program, GEMS grew out of a Department of Energy demonstration project for the food industry headed by Glen Lewis, a former Del Monte logistics specialist who has been active in both California and federal environmental and energy management initiatives in recent years. After demonstrating GEMS at Bell Carter Foods, he installed GEMS at half a dozen food companies prior to Sierra Nevada. The software is being brought to market under his Lewis Energy & Technology Systems umbrella.

With solar power, hydrogen fuel cells, biogas and other on-site energy sources, Lewis’s system is dealing with its most complex energy mix. Because of the on-site generation, he says weather conditions at the local airport will be part of the calculations. Weather’s impact can be significant: Brush fires last year created so much smoke, electric yield from the brewery’s solar panels declined 16 percent.

Empowering staff to reduce costs and greenhouse gases might have even more impact. “There’s a huge behavioral aspect to this,” says Lewis. “If you point out to most people the savings that can be realized from changing behavior, they’re going to do it.”