Greening Aquarium of the Bay: Recommendations for Reduced Environmental Impact A 2012 Group Project Final Report Draft Researched and Produced By: Matt Blazek Max Broad Brittany King Scott Salyer Faculty Advisor: Professor Hunter Lenihan Greening Aquarium of the Bay: Environmental Impact & Recommendations for Reduction As authors of this Group Project report, we are proud to archive it on the Bren School‘s website such that the results of our research are available for all to read. Our signatures on the document signify our joint responsibility to fulfill the archiving standards set by the Bren School of Environmental Science & Management. ____________________________________ ____________________________________ Matthew Blazek Brittany King ____________________________________ ____________________________________ Max Broad Scott Salyer The mission of the Bren School of Environmental Science & Management is to produce professionals with unrivaled training in environmental science and management who will devote their unique skills to the diagnosis, assessment, mitigation, prevention, and remedy of the environmental problems of today and the future. A guiding principle of the School is that the analysis of environmental problems requires quantitative training in more than one discipline and an awareness of the physical, biological, social, political, and economic consequences that arise from scientific or technological decisions. The Group Project is required of all students in the Master‘s of Environmental Science and Management (MESM) Program. It is a three academic quarter activity in which small groups of students conduct focused, interdisciplinary research on the scientific, management, and policy dimensions of a specific environmental issue. This Final Group Project Report is authored by MESM students and has been reviewed and approved by: ______________________________ Hunter Lenihan, PhD June 2012 2 | P age Table of Contents 1. Abstract ................................................................................................................................................. 5 2. Executive Summary .............................................................................................................................. 6 3. Background ........................................................................................................................................... 8 3.1 About the Aquarium ..................................................................................................................... 8 3.2 Research Question ........................................................................................................................ 8 3.3 Project Objectives ......................................................................................................................... 8 3.4 Research Focus ............................................................................................................................. 9 3.4.1 Energy ................................................................................................................................... 9 3.4.2 Animal Care ........................................................................................................................ 10 3.4.3 Pumping .............................................................................................................................. 11 3.4.4 Water Cooling ..................................................................................................................... 13 4. Methods............................................................................................................................................... 15 4.1 Animal Care ................................................................................................................................ 15 4.1.1 Mortality ............................................................................................................................. 15 4.1.2 Feed Cost ............................................................................................................................ 15 4.2 Pumping ...................................................................................................................................... 16 4.2.1 Hydraulic System Analysis .................................................................................................. 17 4.2.2 Filters .................................................................................................................................. 19 4.2.3 Operating Point................................................................................................................... 19 4.2.4 Motor Calculations ............................................................................................................. 19 4.2.5 Affinity Laws ....................................................................................................................... 19 4.2.6 Power Conditioners ............................................................................................................ 20 4.2.7 Demand Response Plan ...................................................................................................... 21 4.2.8 Renewable Energy Purchase Option .................................................................................. 23 4.3 Water Cooling ............................................................................................................................. 24 4.3.1 Heat Sources ....................................................................................................................... 24 4.3.2 Existing Chiller ................................................................................................................... 28 4.3.3 Alternative Scenarios .......................................................................................................... 30 4.4 Cost-Benefit Analysis ................................................................................................................. 35 5. Results ................................................................................................................................................. 36 5.1 Animal Care ................................................................................................................................ 36 3 | P age 5.1.1 Total Mortality .................................................................................................................... 36 5.1.2 Rockfish and Temperature .................................................................................................. 38 5.1.3 Rockfish and Temperature without sensitive species .......................................................... 39 5.1.4 Feed and Temperature ....................................................................................................... 39 5.2 Pumping ...................................................................................................................................... 40 5.2.1 Hydraulic System Analysis .................................................................................................. 40 5.2.2 Motor Replacement ............................................................................................................. 43 5.2.3 Additional Pumps ................................................................................................................ 43 5.2.4 Variable Frequency Drives (VFDs) .................................................................................... 44 5.2.5 Demand Response Plan: Raw Water Pump ........................................................................ 45 5.2.6 Power Conditioners ............................................................................................................ 46 5.2.7 Renewable Energy Purchase Option .................................................................................. 46 5.3 Water Cooling ............................................................................................................................. 47 5.3.1 Baseline Heat Sources & Sinks ........................................................................................... 47 5.3.4 Alternative Scenarios .......................................................................................................... 50 6. Discussion ............................................................................................................................................... 57 6.1 Animal Care ................................................................................................................................ 57 6.2 Pumping ...................................................................................................................................... 58 6.3 Water Cooling: ............................................................................................................................ 60 7. Scenario Recommendations ................................................................................................................ 62 7.1 Scenario 1: Carbon Focused ....................................................................................................... 62 7.2 Scenario 2: Animal Focused ....................................................................................................... 63 7.3 Scenario 3: Balanced................................................................................................................... 64 8. References ........................................................................................................................................... 67 9. Acknowledgements ............................................................................................................................. 74 10. Appendices ...................................................................................................................................... 75 4 | P age 1. Abstract As a certified San Francisco Green Business, Aquarium of the Bay (AOTB) is in search of new ways to improve its environmental performance. The major objective of an aquarium is to provide life-support for aquatic organisms, and for AOTB this means maintaining over 20,000 marine animals. Animal care is highly energy intensive, and AOTB expends 89% of its electricity consumption maintaining appropriate water temperatures for exhibits, and pumping 100,000 gallons of water per day through its multi-tank facility. We addressed the question of how AOTB might reduce its electrical costs and carbon footprint while meeting animal care needs. By analyzing pumping and cooling operations, exploring alternative technologies, and conducting a cost-benefit analysis, we formulated a set of recommendations designed to maximize energy efficiency and minimize the aquarium’s costs and carbon emissions. Our results indicate that over a 20-year period, AOTB can substantially reduce energy consumption by installing low-cost cooling fans, insulating pipes, implementing variable speed pumps, decreasing system head, using energy saving power conditioners, and removing three species of temperature sensitive rockfish. On an annual basis, this plan would save the aquarium $48,000, reduce carbon dioxide emissions by 10,000 lbs, and reduce temperature-related mortality. Our multidisciplinary research approach balanced environmental performance, cost, and animal welfare to help foster AOTB’s mission in an environmentally sustainable way. 5 | P age 2. Executive Summary In 2011, Master’s students from UC Santa Barbara’s Bren School undertook a project designed to enhance Aquarium of the Bay’s (AOTB) environmental performance, with a focus on improving energy efficiency within the life support system that maintains over 20,000 marine organisms. The project’s specific goal was to provide recommendations for reducing energy consumption related to water flow and temperature control, processes which are critical for animal welfare but that account for about 89% of the aquarium’s annual energy expenditures. Methods for improving the Aquarium’s environmental performance were identified and analyzed based on their ability to reduce carbon dioxide emissions, improve cost-effectiveness, and maintain animal welfare. A cost-benefit analysis was performed for each recommendation, and Scope 2 carbon dioxide emissions were calculated to determine the carbon footprint from electricity consumption. Both the net present value and carbon footprint were calculated using a 20-year time horizon. 2.1 Pumping Maintaining animal welfare and high water quality requires adequate water flow through a complex network of displays, and cooling and filtration systems. AOTB uses a total of 35 pumps to move water through their facility, which represent 67% of the Aquarium’s energy expenditures. The following improvement options were assessed:  Motor replacement: Each pump is paired with a motor, and replacing 16 of the motors with more efficient models would save the Aquarium an estimated $49,552 and 280,663 lbs of CO over 20 years. 2  Variable Frequency Drives (VFD): If a pump is running below its maximum load, a VFD can save energy by adjusting the speed of the motor. The Team proposed replacing filtering material in the Aquarium’s sand filtration system, and replacing high-resistance meters to increase flow and decrease head. Combining these changes with a VFD would save the Aquarium an estimated $328,489 and 1,906,740 lbs of CO . 2  Demand Response Plan (DRP): The price of electricity and associated CO vary during the 2 day, increasing with demand. By shifting operating times for equipment such as the raw water pump to off-peak hours when the demand is low, the Aquarium can save $37,639 and 501,180 lbs of CO . 2  Power Conditioners: A motor’s power factor (PF) describes its ability to convert electricity into work. Power conditioners correct the PF by storing electricity and discharging it to the pump motor, as needed. Installing a power conditioner would improve the PF of pumps by about 8%, which will save $285,024 and 1,344,280 lbs of CO . 2 2.2 Temperature Control When water temperatures exceed 14°C, fish mortality and disease increase significantly. Water temperature is maintained by a main chiller, which consumes 29% of the energy spent on life support. 6 | P age  Insulation: By insulating the pipes in the system, heat gain can be reduced in water transferred from the chiller to the aquarium tanks. Insulation will save energy by reducing the load on the chiller. Installation costs are high and will generate a negative net present value (NPV) of -$195,073, but also could save 191,861 lbs of CO annually. 2  Fan: Installing a fan above the main tanks will generate heat loss through evaporation, which is a more energy efficient means of cooling the water than chilling. The fan saves energy by reducing the load on the chiller, and would generate a positive NPV of $193,589 and save 1,033,433 lbs of CO emissions. 2  New chiller: An additional main chiller would also cool water effectively but would be very costly, generating a NPV of -$18,635,742, and increasing AOTB’s carbon footprint by 87,323,355 lbs. 2.3 Animal Care  Remove sensitive fish species: Three species of rockfish (black, brown, and grass) account for 25% of total mortality in Tank 1. Most of that morality (72%) occurred when water temperatures rose above 14°C. AOTB can decrease mortality without increasing chilling capacity by removing these three highly sensitive species. 2.4 Renewable Energy  CleanPowerSF: A new local electricity provider, CleanPowerSF, expected by mid-2012, will provide electricity from 100% renewable sources but cost an additional 2 cents/kWh. Switching to this provider will cost AOTB an additional $658,361, but save 22,387,460 lbs of CO , an amount equal to their entire Scope 2 emissions. 2 The Team’s analyses were incorporated into three scenarios. Scenario 1 focused on reducing carbon emissions to the least possible extent. Scenario 2 emphasized improving animal welfare with the minimum carbon emissions increase. Finally, Scenario 3 balanced the reduction of carbon emissions, cost savings, and improved animal welfare. The three scenarios presented a range of options that the Aquarium can evaluate based on their needs. The Team recommends that AOTB adopt Scenario 3, which saves money, enhances animal welfare, and increases environmental performance. This greening strategy will increase flow through the main exhibits by upgrading equipment and removing sensitive fish species to decrease temperature-related mortality. At the same time, Scenario 3 would decrease costs by $671,000 and CO emissions by 3,967,510 lbs over 20 years. 2 7 | P age 3. Background 3.1 About the Aquarium Aquarium of the Bay (“AOTB” or “Aquarium”) is a popular marine animal center located on San Francisco’s Pier 39, drawing 600,000 visitors per year. It opened in 1995 and was purchased in 2009 by The Bay Institute, a non-profit organization dedicated to the conservation of San Francisco Bay and its watershed. A key goal of the Aquarium is to educate the public about the local marine populations and important related environmental issues. The operation includes two gift shops, administrative offices, life support facilities and exhibits displaying over 20,000 aquatic animals. The central features of the facility are two underwater tunnels, which total 300 feet in length and sit beneath large tanks containing 740,000 gallons of sea water. In 2005, the Aquarium was certified as a San Francisco Green Business, an effort which included diverting 80% of their waste and making energy efficiency improvements. To build upon these achievements, AOTB approached the Bren School of Environmental Science & Management about taking the next step in their sustainability efforts. Though substantial accomplishments were realized through the Green Business certification process, it only applied to the retail side of the Aquarium, neglecting impacts from the life support systems. It turns out that approximately 89% of the facility’s energy is expended on the latter, so the Bren School team (Team) decided to focus on alleviating environmental impacts from life support systems. From the preliminary analysis, the Team concluded that the Aquarium’s water impact was negligible. Although AOTB draws in up to 50,000 gallons of salt water per day from the San Francisco Bay, they send it to sewage to be treated and returned to the ocean. Conversely, energy consumption by the life support system represents a significant carbon impact, releasing over 1.2 million pounds of CO per year. Water pumping and water cooling are the main sources of this 2 consumption, both which are necessary to maintain animal well-being. A major challenge faced by the Team was to balance the often-conflicting sustainability objectives of improving biological health and decreasing environmental impact. 3.2 Research Question The Team formulated a research question to guide the project analysis and outcomes: How can the Aquarium improve its environmental performance in a cost-effective way while still maintaining excellent animal care standards? 3.3 Project Objectives There were three main objectives of the project. First, the Team had to establish a baseline for energy use, Scope 2 carbon dioxide emissions, and biological health to have a means of comparing results. Second, the Team had to identify new methods and processes that will reduce environmental impacts and improve animal welfare. Thirdly, the financial feasibility of the proposed methods and processes needed to be analyzed in order to determine whether each suggestion would be viable for the Aquarium. 8 | P age 3.4 Research Focus 3.4.1 Energy Motivating the project is the growing global and national demand for energy. According to the U.S. Energy Information Administration (EIA), 505 quadrillion Btu of energy were consumed throughout the world in 2007 (EIA, 2011a). More importantly, the United States accounted for 21% of world energy consumption. With approximately 4.5% of the world’s population, the U.S. is using energy at a per capita rate much higher than many of its peers. U.S. electricity demand in 2009 was 3,745 billion kilowatt hours (EIA, 2011). Of this, about 3% is used for water and wastewater systems (EPRI, 1994). The implications of this energy consumption pattern are serious because of the associated environmental problems arising from energy production, consumption, and pollution. Most prominent among these issues are greenhouse gas emissions (GHG) and global warming effects. In the U.S., buildings account for 42% of electricity usage (IEA, 2011). Moreover, Aquarium facilities likely use more energy per square foot than the average building due to the energy intensive nature of life support systems (LSS). Furthermore, the City of San Francisco set a goal to reduce carbon emissions and energy consumption by 20% below 1990 levels, or by about 3.6 million tons of carbon dioxide (SF DOE, 2004). To meet this goal, businesses will need to become more energy efficient. To maintain its reputation as an environmental leader, the Aquarium must build upon their previous improvements to help the City of San Francisco reach its environmental benchmarks. The Team determined that approximately 89% of electricity is being used for marine animal life support, while only 11% is being used for all other facility systems, including lighting, heating, and cooling. Life support systems include water pumps, chillers, ozone filtration and other minor systems. Of the LSS consumption, 60% is due to pumping and 29% to the remaining equipment (Figure 1). The bulk of the latter category can be attributed to the facility’s main water chiller. Aquarium of the Bay’s life support system consists of three major hydraulic systems: the raw water pump, the main system, and the side loop systems. The raw water pump brings in sea water from the nearby pier into the facility and is served by a 7.5 horsepower (hp) pump that operates only when make-up sea water is needed. The main life support system serves the aquarium’s Figure 1: Facility Energy Consumption Breakdown two large tanks, Tank 1 and Tank 2 or “T1” and “T2.” Each tank has its own pumping infrastructure, with three 25 hp pumps, which are designed to operate at 900 gallons per minute (gpm) each. This system also includes side loops to deliver water to the water chiller and ozone filters. The ozone filters have two 10 hp booster pumps for each tank. 9 | P age 3.4.2 Animal Care The Aquarium houses more than 20,000 marine animals that are displayed in a variety of exhibits. The goal of the aquarium is to educate visitors about the San Francisco Bay and adjacent Pacific Ocean species and habitats. Achieving this goal requires that AOTB maintain environmental conditions within exhibits that adequately mimic those of the natural environment. The LSS does this primarily by controlling the water flow rate that in turn regulates temperature, oxygen concentration, and water clarity, factors that are also influenced by the system’s filtration process. Aquarium of the Bay’s main exhibit, Under the Bay, features two large tanks, T1 and T2, which provide visitors a unique underwater Bay experience. T1 is contains mostly near shore species indigenous to the San Francisco Bay and the adjacent Pacific Ocean, including anchovies and a variety of rockfish species. Tank 2 is made up of the larger deeper-water species such as seven- gill sharks, sturgeons, and rays. Not only are the two tanks comprised of both near-shore and deeper-water species from different locations (San Francisco Bay and the Pacific Ocean), they also receive the same water supply. Therefore, it is important that water characteristics are suitable for a variety of species. 3.4.2.1 Temperature The San Francisco Bay has a seasonal temperature range of 10.5°C – 18.9°C (NODC 2012), with warmest temperatures occurring in the summer and coldest temperatures in the winter. The Aquarium’s staff strives to keep water temperatures within the range of 9-14°C. Although temperatures in this range are suitable for a wide variety of species, one key reason for the selected range is the presence of rockfish in the Aquarium. Most of the rockfish live in T1, with 21 species of rockfish, totaling over 400 individuals. Although some rockfish species can be found at shallower depths, most rockfish species are typically found in deeper, colder water (Green and Starr 2011), making them more sensitive to temperature fluctuations than other species. 3.4.2.2 Mortality Mortality in aquarium exhibits are caused by natural factors, including predation and complications with reproduction, but also by factors associated with the LSS. In particular, animals can be threatened when the water sees low dissolved oxygen levels, variability in salinity, or erratic temperature fluctuations. Over the past two years (2010-2011), Aquarium animal care staff have documented mortality and health issues, including an ailment affecting rockfish called exophthalmia, also known as “pop-eye”, which is caused by a bacterial or fungal infection (Seng et al., 2006). Pop-eye is also caused by the build-up of gas in tissues that eventually enters the eye cavity causing the eye to bulge (Dehadrai, 1966). Due to the possible spread of the disease to other animals, and undesirable appearance for visitors, rockfish suffering from exophthalmia are relocated to a quarantine tank where they recover or, eventually, are euthanized. Aquarium staff have noted that rockfish mortality appears to increase when water temperature exceeds 14oC. 10 | P age