Pairing local renewable energy resources with smart technologies can ensure reliable, efficient, and cost-effective power supplies.
By Karla Hignite
Take a good look around. The most promising energy solutions for your campus may be in sight or underfoot.
Ten years ago, many would have described the University of Minnesota, Morris, as a little college on the prairie, says Lowell Rasmussen, vice chancellor for finance and facilities. Today Morris is better known as a test bed of energy development located in the geographic center of the state's wind and biomass resources. The Morris community has undergone a cultural shift as it has come to grips with the question of how to live in concert with its surroundings, Rasmussen says.
The most secure and cost-effective power position an institution can assume may in fact rest on learning how best to tap the assets out its front door. "You can't determine the best solutions for your campus unless you first understand what is available to you where you are," says Rasmussen.
"Our solution will be different from what may work best in northern Minnesota, or in the urban centers of our state, because the resources will vary. What's important is to understand the carbon streams around you and how those can support your energy needs."
Developing a comprehensive energy strategy that balances cost, carbon impact, and reliability is similar in some ways to managing an institution's investment portfolio. A strategic energy blend can protect an institution against price vulnerabilities and compound the benefits that result from a complementary mix.
At institutions across the nation, wind, solar, geothermal, and biomass are among the clean alternative energy contenders that are factoring into the power equations for more colleges and universities seeking to wean reliance on fossil fuel-intensive energy sources. Combine those low- and no-carbon power sources with smart technologies that squeeze every possible kilowatt hour from on-site campus energy supplies and an institution's goals for carbon neutrality or energy independence edge closer to within reach.
Following are examples of four institutions that are employing this two-pronged strategy.
Harnessing Prairie Resources
University of Minnesota, Morris
A decade ago, the Morris campus was heated by natural gas and powered primarily by coal-fired electricity supplied by its local utility. Under that energy mix, the total annual carbon impact for the Morris campus was approaching 12,000 metric tons. Today the campus is essentially energy independent, thanks to on-campus wind power and a biomass gasification plant. Combined, these local energy solutions have slashed greenhouse gas emissions by 80 percent to less than 2,500 metric tons per year.
Prairie Grass Becomes Biomass
For Morris, the catalyst for taking stock of available energy assets was prompted in part by price spikes in natural gas that were wreaking havoc with the institution's utility budget. At that point, leaders started assessing alternative-energy sources to which the campus had ready access.
"Pretty much as far as the eye can stretch, you see cornfields and prairie grass," says Rasmussen. "That prompted us to do the math." How much plant material would it take to heat and cool the campus? "We arrived at an estimate of 8,000 tons per year. To put that in context regarding availability, we surveyed our region and found that in our county alone there was about 600,000 tons of potential source material," says Rasmussen.
Because corn stover—the waste material of the crop, including its leaves, cobs, and stalks—is not a commodity, any fluctuations in price are relatively small, explains Rasmussen. And, removing a portion of this from the fields is actually beneficial for farmers, he adds. (See sidebar, "Energy Production Leads to Student Education.") "The simple exercise of seeing a crop of corn or a field of prairie grass in a new light helped us focus on where we should position our energy future and moved us in quite a different path."
The campus's biomass gasifier, fueled by crop residues from nearby farms, is part of an integrated system for heating and cooling campus buildings. The Morris campus is currently operating at about 40 percent biomass and 60 percent natural gas. "Eventually we will reposition that allocation to 80 percent of our thermal cooling and heating using biomass and only 20 percent or less through natural gas, which we will use only on extreme days of really hot or really cold weather," says Rasmussen.
Cost is the primary reason Morris is not yet running at capacity with biomass resources. "Recently, natural gas has been fairly inexpensive, but we know there will come a time when it will be cost-effective to shift primarily to biomass, since history has shown us that natural gas prices can be quite volatile," notes Rasmussen.
The shift in energy resources has caused a shift in energy spending toward support of regional energy production, says Rasmussen. "Ten years ago the $600,000 we spent on natural gas went mostly out of state. Today, we expend about $400,000 per year on biomass purchases that stay within a 20-mile radius of our community."
Let the Wind Blow
In March 2011, when the university's second 1.65-megawatt wind turbine went online, Morris boosted its on-campus electrical output to 70 percent. In actuality, any time the wind is blowing at least 15 to 20 miles per hour, which is fairly often in Morris, the campus is producing more energy than it can use.
However, since the capacity to efficiently store wind power doesn't yet exist, the campus sells its excess energy-up to 60 percent of the total produced-back to the grid. The distributed generation arrangement between the Morris campus and its local utility is somewhat unique, adds Rasmussen. "We own the turbines and the lines to our campus, and we decide how much power we want and can use. That gives us the ability to manage our demand."
Currently Morris does not use any grid-supplied electricity about 30 percent of the time. A 20-year power purchase agreement with its utility provides the Morris campus with a fixed price for the energy it does consume. "This is still a learning process for us to understand how to maximize use of our available natural resources to our greatest cost advantage," says Rasmussen.
"A key take-home point from our experience is that we never would have been able to get to the kind of carbon reductions and on-campus energy production that we have by using wind or biomass alone," says Rasmussen. "The combination of these two robust resources is what has pushed us far beyond what we would have imagined possible even a few years ago. By combining wind, which currently is not a storable energy solution, with biomass, which we can store, we've been able to maximize the outputs of both."
Managing Both Sides of the Meter
"By combining wind, which currently is not a storable energy solution, with biomass, which we can store, we've been able to maximize the outputs of both."
Lowell Rasmussen, University of Minnesota
Morris is also applying smart technology to its energy operations. "Our approach to energy management is an opportunistic one," says Rasmussen. "We continually monitor all our resources to know how to manage the load to our best conditions, because it's in our best interest to capture as much as possible of the energy we produce for our own use." He points out that while many have long focused on energy demand, becoming a strategic manager of energy resources requires equal attention to the supply side.
"For instance, we can look at tomorrow's weather forecast in conjunction with the information provided by our local utility regarding next-day pricing so that we can project our best mix based on estimated wind resources, air temperatures, and the price of natural gas compared to biofuels. We can then run this through our matrix according to specific criteria we set to predetermine which systems we might bring online the next day and which ones we won't need to run. And based on that, we can decide how much grid-supplied electricity we want to use and how much power we want to produce for our own consumption," explains Rasmussen.
Adding intelligence to energy management systems is also key for becoming more sophisticated in understanding how best to store energy, for which smart metering will continue to play an increasing role, says Rasmussen. "When we know that during a summer day in July, outside temperatures will reach the 90s, and that electricity will cost 10 cents per kilowatt hour at 1 p.m. but only three cents per kilowatt hour at 3 a.m., artificial intelligence tells us to start precooling that building at 3 a.m. when energy is least expensive."
The same concept can be applied for preheating a building, explains Rasmussen. "As we continue to seek capability for energy storage, addressing how we can most efficiently use the energy we have is key, even through such rudimentary forms of precooling and preheating."
Rasmussen believes that none of this knowledge should be lost on the consumer. The Morris campus is currently working with the manufacturer of its second wind turbine to develop a downloadable application that tracks the turbine's performance in real time so the entire campus community can use the information to make personal energy choices. "With this application, students will know how much it will cost to dry their clothes at 1 p.m. versus at 10 p.m.," says Rasmussen.
He explains, "When we begin informing consumers about energy flows and excess electricity-that helps us keep those electrons on campus." And if that kind of detail is available at a smart phone level, consumers will better understand how their actions drive energy demand and cost and will be empowered to manage their own carbon footprint.
Energy Contingency Planning
Santa Clara University, California
While the long-term energy strategy for California's Santa Clara University doesn't include energy independence as a goal, energy security is a primary aim for SCU. Subsequent to a university visioning process launched in 2004, institution leaders initiated a study to determine an appropriate energy plan for the campus for the next 20 years.
The priorities were fourfold: Increase control over energy costs, increase reliance on green energy sources, reduce the university's carbon footprint, and develop enough reliable on-site power to continue campus operations during grid disruptions.
Santa Clara University is in the process of developing its own smart grid so that it can isolate the university from its local university to manage and maintain campus facilities and systems.
"We consider that final priority a key component of our institution's overall risk management and business continuity plan," says Robert Warren, vice president for administration and finance. After studying a range of alternatives, university leaders arrived at a mix of strategies and options appropriate to the SCU campus and outlined three primary approaches: Reduce energy demand, increase on-campus energy supply, and develop a smart grid to maximize energy use.
To reduce demand, leaders focused comprehensively on infrastructure (lighting, building systems, and building design) and on human behavior, encouraging students, faculty, and staff to become more conscious of their personal-resource consumption. Despite a 20 percent growth in facility space during the past five years, overall campus energy use has declined by 20 percent, along with a 25 percent reduction in greenhouse gas emissions during that same time period, reports Joseph Sugg, assistant vice president, university operations.
Currently SCU purchases about 95 percent of its electrical load, paying its local utility a slight premium for wind and other clean energy sources included in its mix. "We use about 30,000 megawatt-hours of electricity each year, with our peak demand—about 5 megawatts—occurring in May and September afternoons when the majority of the university's 9,000 students are on campus with all our air conditioners humming," Sugg explains.
The average daily demand is closer to 4 megawatts, down to a minimum demand of 2 megawatts overnight. All that is important to know in arriving at a solid estimation of what it would require to avoid disruption of campus operations in the event of a loss of utility-supplied power, notes Sugg. "We've estimated that we need to produce approximately 3 megawatts of our own power to remain operational."
To date, the university has installed 1 megawatt of solar power on campus rooftops through a third-party power purchase agreement that offers a fixed utility rate with an option to buy the system at the end of the lease agreement. "While our solar is doing a great job of helping the university manage its peak load—supporting about 20 percent of the university's summer daytime demand and significantly reducing stress on the grid-it is an intermittent power source and can't be relied on 24/7," notes Sugg.
While the area's best wind resources are east of the campus, the university is testing a low-profile turbine to see whether wind power would make a viable contribution to the campus energy supply. Also under consideration are geothermal-sourced heat and electricity.
"Because we are situated on a very fertile archeological site, it would not be possible for us to lay a network of pipe across the entire campus for distributed heat and power," explains Sugg. Even so, campus leaders are considering how they might develop a series of mini cogeneration plants that would tie smaller clusters of two or three buildings together.
What campus leaders are most focused on now is a 1-megawatt fuel cell project under evaluation. "We currently have
1.2 megawatts of diesel generation capacity as a backup power source that we can run if the local grid goes down. The reason we're so excited about the fuel cell project is that it would essentially replace the diesel as a reliable base load," Sugg says. "We believe this could offer a viable solution for producing efficient, essentially benign energy that we could use as our base load 24 hours of the day."
The Big Green Box
"It is not our goal to become grid-independent by producing all our energy needs on campus. If the grid is operating, we would rather take advantage of power that is less expensive than what it costs us to produce," explains Sugg. "What we do want is the capacity through our own campus energy supplies to continue operations throughout any utility grid disruptions."
In fact, SCU is in the process of developing its own smart grid so that it can isolate the university from its local utility to manage and maintain campus facilities and systems. While the university's current energy-management system allows for control of HVAC systems and building temperatures, a smart grid will let facilities operators ration electricity across all buildings to keep power demands below the level of available campus energy supplies.
SCU has completed the first phase of its smart micro-grid installation. Once fully complete, the grid will connect all 70 campus buildings that are considered critical to the system so they can be managed as a whole. Even during normal operations, the grid will allow the university to maximize energy savings by tying the power source-whether that's on-site solar or fuel cell, or grid-supplied electricity—to actual consumption requirements.
"We envision incorporating our classroom schedules and other information about building occupant use into this system so that specific rooms or sectors can be powered down when not in use," explains Sugg. "Eventually, we also plan to use the intelligence of this system to control energy costs by changing energy sources between grid-supplied and our own so that we are producing and purchasing energy at its lowest cost."
The smart micro-grid system will also allow the university to monitor and control its carbon impact, notes Sugg. "We'll be able to program the system based on preset conditions and priorities so that if energy demand is low and our on-campus output is high, we could throttle back on our diesel generators to rely more on our solar-generated power."
Ultimately university leaders expect to reduce total energy consumption by as much as 50 percent and save about 20 percent in energy costs simply through improved and intelligent energy management.
The university is working with a Silicon Valley company to develop its "green box" smart-grid technology and has already successfully tested its application. A trial run isolating a campus facilities building allowed operators to program system priorities with regard to temperature, lighting, fan controls, and energy resources. Everything worked as designed.
Soon after the test, the municipal grid suffered a short-term outage. While the rest of the campus experienced a lapse in power, the test facilities building—still connected to the box—worked to perfection.
University of California, Irvine
For a large research institution in particular, the most direct path to the greatest and immediate energy cost savings and emissions reductions is through maximizing energy efficiency. That's especially true when you consider that laboratories consume two thirds of the total energy used by a typical research-intensive campus, says Wendell Brase, vice chancellor, administrative and business services, University of California, Irvine.
It seems a no-brainer: The less energy you consume, the less you spend, the less you emit. And yet, achieving the kind of deep cuts needed going forward will require some deep financial commitments. "All the quick-payback retrofits have been made," says Brase, who also serves as chair of the University of California System's climate-solutions steering group.
"If you look at the UC system as a whole, our 10 campuses account for a combined 2 million metric tons per year of greenhouse gas emissions. That's not actually that bad compared to some universities that may approach a million metric tons per year on one large campus, due to a coal-based energy infrastructure," notes Brase.
The reason laboratories account for such a high percentage of an institution's utililty load is largely due to their air-handling design. Furthermore, many lab buildings run these air-handling systems at a constant volume regardless of business activity.
Those comparisons aside, last year the UC system imposed a policy level goal for each of its campuses to achieve year 2000 emissions levels by 2014. That alone will entail a 25 percent reduction in current greenhouse gas emissions, notes Brase. Then there is Assembly Bill 32, California's Global Warming Solutions Act, which requires municipalities and state government entities to achieve 1990 emissions levels by 2020.
"Getting to that will require a 50 percent systemwide reduction—down to a combined total of 1 million metric tons," says Brase. "That's a radical reduction beyond what will be attainable through reduced energy consumption." To get there, the UC system will need to max out deep energy-efficiency retrofits and develop large-scale renewable energy projects both on campuses and off-site.
With regard to increasing on-site renewable energy production, the system is looking not only at solutions appropriate for individual campuses—solar for some, wind for others, perhaps geothermal for a few—but also at large-scale systemwide initiatives.
"Even if we put solar arrays on every rooftop and parking structures on every UC campus, that would yield less than a 5 percent reduction in our overall carbon footprint," he notes. "As a system, we are currently exploring partnerships for large-scale, collaborative off-site ventures for solar and for biomass. And the latter could be a game changer if we can identify the right solution."
Of the system's combined 2 million metric tons of emissions, Brase explains that the campus can attribute about half to combustion of natural gas in cogeneration facilities. "These combined heat and power plants are highly efficient, so we're not about to scrap them, but what we can and should do is devise a strategy to make them carbon neutral."
The UC system is currently exploring partnerships for developing large-scale anaerobic digesters to take organic waste materials from central California—including cattle, dairy, and plant waste from orchard and food-producing operations—to recover the methane produced as the materials break down. It will take a mega-scale, multisite biogas project to replace all the natural gas now combusted by the UC system.
Reducing emissions requires maximizing the return on energy consumed. "This isn't about reaping a quick and easy 10 percent savings by changing out light bulbs. This is about wholesale redesign of lighting and HVAC systems-projects that can cut energy use and emissions by at least 25 percent or, better yet, 50 percent," says Brase. These are high-investment projects for which the payback can be 10 years or more, but nonetheless are more cost-feasible than renewable energy projects at this point, he adds.
The Really Big Deal
The biggest elephant in the room with regard to tackling energy efficiency systemwide is also the biggest source of opportunity for energy savings for the UC system, notes Brase. "Tackling our research labs is not only a priority, it's a necessity." The good news, he says, is that the knowledge already exists that shows how to make university laboratories 50 percent more efficient.
"We have working examples of retrofits and of new construction that are achieving these levels of savings," he says. Those examples include UC Irvine's Sue and Bill Gross Stem Cell Research Center, which opened in summer 2010, and which is among the most energy-efficient lab buildings of its type anywhere in the world.
The reason laboratories account for such a high percentage of an institution's utility load is largely due to their air-handling design. "A typical lab built in the mid 1990s might exchange the entire volume of air in the building 10 times each hour. That process involves heating, cooling, filtering, dehumidifying, and circulating before that air is forced out of an exhaust stack at 30 to 40 miles per hour," describes Brase. Furthermore, many lab buildings run these air-handling systems at a constant volume regardless of building activity.
Smart technology is now enabling digital controls and advanced sensors to make a laboratory respond to actual, measured usage and sensed environmental conditions, explains Brase. "We first slowed the ventilation rate in our newer laboratories to six air changes. We are now building and retrofitting 'smart laboratories' that vary ventilation rates based on air-quality measurements lab by lab. These may exchange the air as few as four times per hour. And when no one is in a lab bay, it might be possible to reduce this to twice each hour," he says.
However, when air quality measurements exceed threshold criteria, air changes can be increased to 10 or 12 per hour, flushing out a space quickly. "Applying smart technology to these processes not only allows us to be more efficient, but it also provides a whole new information layer that makes a laboratory building safer," says Brase.
Reducing air flows does require other changes, such as reducing overall air-conditioning load. "In many labs, you will find rows of freezers with heat pouring out of them," notes Brase. "We use Energy Star freezers and have improved lighting efficiency by 50 percent compared to only a decade ago." Other efficiency measures offer exponential energy savings, such as using smart sensors to reduce the speed at which air flows though ducts and out the exhaust stacks.
While the possibility exists to dig deep to maximize lab efficiency, Brase concedes that not every institution may be ready to face the fiscal challenge. In California, rebates and subsidies are available that reduce a 10-year payback on a project to 8 years. "In our case, it also is helping us work together as a system because we can scale up programs that offer a good return on investment, both in terms of efficiency and emissions reductions," he says.
Brase warns that deep energy efficiency is more difficult and expensive than the fast-payback measures of the past decade. He adds, "Once carbon bears an actual, monetized cost, that will lower the feasibility threshold for more of these kinds of projects, because discussion will then shift from immediate savings to avoided costs and risks."
KARLA HIGNITE, Universal City, Texas, is a contributing editor for Business Officer.