Gundersen Health System is using a combination of energy conservation, and on-site and off-site renewable energy generation — including anaerobic digestion — to meet its 2014 goal of being fossil fuel free.
Marsha W. Johnston
BioCycle September 2013, Vol. 54, No. 9, p. 36
In May 2008, Gundersen Health System, whose 6,500 employees are based in Wisconsin, Minnesota and Iowa, announced that it would offset 100 percent of any fossil fuel-based energy generation in 2014. The company projected it would take them only five years to offset all use of fossil fuels, despite having 41 clinics in 19 counties, a 325-bed hospital, three critical access hospitals, and a variety of affiliate organizations, including EMS ambulance service, rural hospitals, nursing homes and a hospice. Gundersen determined to reach fossil-fuel independence by reducing energy consumption, increasing energy efficiency in its buildings, and investing in renewable energy generation — both on-site where feasible and off-site, where the power generated would offset any fossil fuel consumption (Figure 1).
“We just said, `We think this is possible, both fiscally, environmentally and health-wise,’” explains Jeff Rich, executive director of Gundersen’s Envision environmental stewardship program. “We needed to live our mission better and saw a cost opportunity for our patients.” Rich, along with Corey Zarecki, Gundersen’s director of Envision, acknowledges that the ambitious project “is not the normal thing you would do as a health system.” But he says Gundersen’s “visionary” CEO Dr. Jeff Thompson and its board of directors see the project as clearly tied to its mission and delivering affordable care.
Figure 1. Gundersen Health’s energy independence plan [/caption]John Ebers, Associate Director of the Facility Engagement and Energy Program for Practice Greenhealth, a Reston, Virginia-based nonprofit with nearly 1,200 hospital members committed to greening their facilities, agrees: “If we truly take seriously the Hippocratic oath, to not do any harm, then not using fossil fuels has to be part of that.” Indeed, in May 2010, the American Heart Association issued a paper declaring that the scientific evidence linking air pollution to heart attacks, strokes and cardiovascular death has “substantially strengthened.”
Of its members, which include Gundersen, Ebers says the Midwestern health provider is unique. “In this business, we see tons of companies claiming to be first in this or the first in that, and for me, a lot of it has become white noise, but what Gundersen is doing is amazing. We have companies going out and purchasing 100 percent renewable energy, but at the level of Gundersen — buying wind turbines, and having lots of renewable energy on-site like geothermal, triple EEE windows — nobody else is doing that. And I feel confident saying it, because I think we would probably know!”
To become energy independent, Gundersen faced the daunting challenge of producing enough renewable energy to equal the approximately 380 million kBTUs it consumed every year. “Our energy goal is to produce more clean BTUs,” notes Rich. “We are attacking heat BTUs because we use more heat.” Its energy bill for all BTUs in 2008 was $5.3 million, and was increasing by approximately $350,000 annually, making it harder and harder to deliver affordable services. In that, Gundersen was not unique. The Department of Energy estimates that U.S. hospitals are 2.5 times more energy intensive than commercial office buildings. This is due in part to the fact that, unlike many other commercial buildings, hospitals must remain fully operational 24 hours a day, seven days a week and provide services during power outages, natural disasters, and other events that would force other facilities to close.
Conservation, Renewable Energy Generation
To ease the task, Gundersen spent the first two years on measures to reduce energy use in its total of 2 million square feet (sq ft) of space. “We reduced our energy consumption per square foot by 25 percent,” says Rich. “This is the one I try to preach because, even if you can’t do renewables, it is the step you can take and make a huge difference. You can save 20 to 30 percent!” Rich notes that 90 percent of its BTUs are consumed in only 6 buildings and campuses in La Crosse and Onalaska, Wisconsin, because they include energy- and heat-intensive hospitals, surgery and data centers. The rest is spread over its 41 other buildings. Two of those six facilities are already energy independent: The two large buildings on its Onalaska outpatient campus, totaling 350,000 sq ft, and its La Crosse facility, comprising four large and several smaller buildings for a total of approximately 850,000 sq ft, including a 550,000-sq ft 325-bed hospital.
The Onalaska campus became the first energy-independent health care campus in the country in March 2012 when it started up a 1.137 MW GE Jenbacher engine fueled by conditioned landfill biogas from the La Crosse County Landfill. Under the contract negotiated between Gundersen and the La Crosse County Solid Waste Department, the landfill installed gas collection and biogas treatment equipment (supplied by Unison Solutions, Inc.), and a 1.6-mile pipeline from the landfill to Gundersen’s Onalaska campus. The biogas is sold to Gundersen. The biogas conditioning system treats 350 scfm of landfill gas. The generator is owned by Gundersen, and provides all of the heat and electricity for the Onalaska campus. Electricity not used on-site is sent to the grid. The landfill gas-fueled project accounts for 11 percent of Gundersen’s total heat and electricity consumption (Figure 2).
Since last March, the majority of the steam and heat used by its La Crosse location comes from a wood waste-fired boiler. Using one 400-kW back-pressure steam turbine, the boiler also produces 2.5 million kWh/year of electricity, enough to meet 38 percent of the company’s entire need. “We have a lot of lumber industry, so we are sourcing the wood locally instead of using [imported] natural gas,” explains Rich. “Wisconsin imports roughly $18 billion in fossil fuels per year, so by doing renewable, locally sourced energy, like the biomass boiler, jobs are going to the mills here rather than another state.” Managing the boiler itself, Gundersen pays per dry ton because the chips can hold up to 50 percent water. “If you pay for half the weight in water, there is no value,” he adds. “We can purchase chips on a dry BTU basis cheaper than natural gas.” A sample from each truckload is run through a moisture content analyzer to determine the dry material weight.
Other direct use heat comes from the 156-well geothermal heat pump Gundersen installed 400 feet below the parking garage of its new 433,000-sq ft hospital, adjacent to the existing La Crosse facilities. By adding nearly 500,000 square feet to its infrastructure, the new hospital, which will open in 2014, set back the Envision project’s progress toward its goal by about 15 percent, but additional renewable energy projects such as the dairy digesters (see next section) have kept them on track. Also by incorporating green design elements, the new hospital will use only 115 kBTUs/sq ft versus the average hospital energy intensity of 250 kBTUs/sq ft. “The biggest piece was the geothermal heat pump, but we also used a wall design to stop thermal bridging, high R-value insulation, thermal window design and occupancy sensors,” says Rich. “We incorporated what we learned from mapping [energy use in our] old buildings.” He adds the new hospital will be LEED certified, though they do not know at what level.
Investing In Anaerobic Digestion
As part of its mix of renewable energy offsets (i.e., generating power off-site to offset fossil-fuel energy used), Gundersen has developed two dairy manure digester projects, which should account for 19 percent of its total energy use. Both in Dane County, Wisconsin, the first digester in Middleton (Springfield Township) is a $14 million, 2-MW complete mix digester with 3 one-million-gallon tanks. Three farms, with a combined total of 2,400 to 2,500 cows, supply manure. “In October we should start filling the main tanks,” says Dane County Executive Joe Parisi. “It takes about a month for it to start producing methane, so we should start generating before year end.” The power will be sold to Madison Gas & Electric, one of the several utilities Gundersen works with over its tri-state region.
The Middleton digester project was facilitated by a $3.3 million pass-through state grant approved in early May and the county’s formal approval allowing Gundersen’s private ownership and operation of the facility. It features a new 1.4 MW generator and a 633 kW combined heat and power (CHP) generator that was redeployed from a biogas utilization project that Gundersen ran in collaboration with City Brewing Company in La Crosse for over 3 years. Details of the second digester in Dane County have not yet been released.
One of the most important pieces of digester deployment, notes Parisi, is its ability to reduce phosphorous runoff from manure. At Middleton, the solids separation process will reduce the phosphorous by 60 percent. Duane Toenges, CEO of US Biogas, which developed and designed the Middleton digester and will develop Gundersen’s second one, notes that in the first phase, once the solids are removed, the effluent will be processed to capture the nitrogen and potassium and will be used as fertilizer for corn, soybeans and alfalfa. The digested solids will be further processed at the facility’s 390-foot-long composting facility that will be run by local composter Purple Cow, which will manage the operation and purchase the compost.
In the second phase of operation at Middleton, adds Parisi, hopefully within a year, new technology will be piloted that should remove 100 percent of phosphorous and reduce liquid content by 70 percent. “In Dane County, we have a chain of lakes that has been challenged because of phosphorous runoff, which results in algae bloom. When you remove that quantity of liquid, it is a huge benefit to our lakes and to our farmers, and helps dealing with manure management.”
Parisi emphasizes the positive attributes of these digester facilities: ”The great thing is that everyone benefits: farmers, Gundersen and the County in its effort to clean up our lakes and our air. Also, what separates manure digesters from other renewables is that they operate 24/7; it is a baseload renewable. You know it will be generating power. There is no shortage of manure in America’s dairyland!” Gundersen’s Rich notes that the digester will also provide an outlet for oil and fat substrates from area restaurants. “We’re bringing [them] in to generate more gas,” he explains. “Typically, they have to pay tipping fees to landfills. They pay us a bit, too, but less.”
The Final Stretch
Counting the wood chip boiler, bioenergy/biomass sources will account for approximately 68 percent of Gundersen’s renewable energy portfolio. Its other renewable sources include: two 5 MW wind farms, each about 30 to 40 miles east and west of the company’s headquarters that together provide approximately 12 percent of the total; a 75,000 kWh solar PV on the country’s first LEED-certified parking garage that Gundersen owns in La Crosse, and two solar hot water heater projects that provide most of the hot water for its on-site day care and renal dialysis centers.
To reach the last mile to 100 percent fossil-fuel-offset status, Rich says the company will rely on additional conservation projects, such as building envelope changes and retrofits on poor performing buildings. Those savings can be substantial, even for recently constructed buildings. Gundersen’s Decorah Clinic in eastern Iowa, for example, was built in 2006, one of its newest buildings. However, it was built with little attention to energy efficiency. Prior to an “energy check-up” by the Envision team, the Decorah Clinic spent nearly $90,000 a year on energy costs. The team made simple fixes, such as retrofitting lights to more efficient bulbs, ballasts and reflectors and scheduling hot water boilers to shut down on nights and weekends. As a result, the clinic has seen a nearly 50 percent reduction in energy use and about $40,000 in annualized savings. With its new hospital, Gundersen spent 3 percent more on construction due to the energy efficiency components, but that difference should save them, at today’s energy prices, half of the facility’s operating costs, or $650,000/year. “Seventy-five percent of the life cycle cost of the building is in operating, only 25 percent in construction,” he explains.
Rich is confident that Gundersen’s energy consumption level will meet its renewable energy production level in 2014 at between 10 and 12 million kBTUs, signaling their energy independence and 100 percent offset status. Overall, he adds, Gundersen will have invested approximately $30 million after grants to reach its goal. A challenging regulatory regime that does not pay customers retail price for energy they generate means Gundersen will have a 7.5-year payback. “If we were in Hawaii or California, it would have been a lot quicker payback, but we are getting savings already,” he explains. “Just from energy efficiencies, our $5.5-million bill is down to $3.9 million. And the on-site stuff, such as the biomass boiler, and heat from the landfill gas, goes into reducing our consumption bar.”
Concludes Rich: “Part of what has made us successful is having a goal that is aggressive in the first place. You have to challenge yourself to think outside the box. I mean, running our campus on landfill gas, who’s doing that? There are always problems and hiccups, but we have made some pretty good progress and we are in the believe mode now.”
Marsha Johnston is a Washington, DC-based freelance writer and communications consultant, specializing in sustainable development and conservation.
Tags: Anaerobic Digestion