Facilities Energy Management Audit and Recommendations at Yellowstone National Park

Abstract

Yellowstone National Park has a difficult challenge ahead in dealing with rising energy costs and concerns of carbon emissions. To deal with this challenge, Yellowstone has tasked itself with reducing its energy consumption by 15%, fossil fuel consumption by 18%, and greenhouse gas emissions by 30% below 2003 levels. The University of Michigan team spent 18 months conducting a facility energy audit on 25 buildings within the park with the goal of adding the park’s green team to achieve these goals. The goals also included providing building specific energy improvement recommendations that could be applied to similar buildings, and exploring policies hindering the development of renewable energy resources in the park. To achieve these goals, data was collect about each building from several different sources. Two years of historical energy use data was gathered in the form of electricity bills and fuel invoices. Use and maintenance information was collected through interviews with key building and maintenance personnel. Each building was audited for building envelope characteristics, HVAC systems, lighting layout and design, and other industrial electronics. This was done by surveying the buildings in person and looking at building blueprints when available. The building surveys included an infrared camera audit which allowed the team to “see” issues areas in the building envelope and systems. Recommendations were developed by looking for improvements in equipment, building envelope, maintenance practices, building use and behavior, and lighting. While each building was analyzed, several common park wide recommendations became apparent. These included lighting upgrades, weather stripping and caulking, maintenance, vending machine management, smart power strips, monitoring and benchmarking, and behavioral changes. Lighting upgrade recommendations take advantage of recent reductions in LED, CFL, and T5 light prices. Upgrading to these lighting types reduces energy consumption and overall demand, while maintaining lighting intensity and quality. These upgrades may not be cost effective to perform in the near term, but it is important to consider these lighting technologies in any future renovations or new construction. Other lighting upgrades include installing occupancy sensors in common areas and installing photo sensors near windows to reduce artificial lighting when there is ample sunlight. Maintaining weather-stripping and caulking is important to minimize the building leaks. The pictures taken with the infrared camera revealed that this maintenance was lacking in many of the buildings. Improving the maintenance schedule will greatly reduce the energy consumed by a building’s HVAC system. Many of the vending machines in the park are old and run continuously. New vending machines have sensors that reduce the energy consumed when there are few or no people using the machine. Old vending machines can be upgraded with off-the-shelf-components to reduce their energy use. Similarly to the vending machine upgrades, smart power strips reduce the amount of energy consumed by “vampire” loads, or loads caused by electronics that are plugged in, but not turned on. These strips work by shutting down the outlets on the strip when specified equipment is turned off, like a workstation computer. Current park practices of tracking electricity bills and fuel invoices do not accurately and sufficiently monitor how and where energy is being used. Current practices also do not allow for establishing a good baseline or benchmarking against other buildings of similar type. Using a program like Energy Star Portfolio Manager allows for quality benchmarking, as well as increasing ii | P a g e the viability of energy use. Improving the systems that use energy in a building is only partially the solution. Changes in how the occupants use the building is just as important. To address this, the team recommends variety of techniques to better education the park staff on energy management programs and on how to include the park staff in future energy management improvements. In addition to the park wide upgrades, it is recommended that the Gardiner Heritage Center establish a more extensive program to maintain the seals on the cold storage equipment in the building. Infrared pictures of the equipment indicated that some units where leaking more cold air than others. Similarly, upright freezers should be considered for upgrades to Energy Star rated chest freezers. This may not be cost effective for newer upright units, but should be considered for any future freezer purchases. The lower Mammoth residences are currently being upgraded, but extra care should be taken to verify that wall insulation is present. It was observed in an infrared picture that a small strip of insulation was likely to be missing in #562. Appliances upgrades are also recommended for all residences. The Mammoth Community Center is a prime example of how building uses change over time and how this creates a building which uses an excess of energy. Many electronic devices were found throughout the building and a thorough audit should be done to remove all unused and unnecessary electronics. Boiler pipes should be insulated as it was found with the infrared camera that much of the heat was emitted into the boiler room itself. From an overall building use perspective, the Community Center has much of its space unused, yet those spaces are still being heated. Considerations should be made on either modifying the builds systems to allow for these spaces to be shut down completely, or renovating the building to better suit its current uses. The Mammoth Fleet Operations Garage is a large consumer of energy in comparison to the other buildings audited. This allows for a large impact when energy efficiency measures are implemented. Although, the nature of the work being performed in the garage bays makes major changes to the energy systems difficult. Current heating units in the work bays are hung from the rafters and attempt to heat the entire space. Upgrading these to allow for heating of the works would allow for a large reduction in energy consumption. Similarly to the Community Center, the boiler pipes supplying hot water to the building should be insulated. The YCC facilities, both dorms and the mess hall, are buildings where use varies seasonally. Upgrading heating systems to radiant propane heating, replacing the electric baseboard heaters along with insulating hot water pipes, and reducing hot water heaters set points are all simple steps to reduce the energy consumption of these buildings. Other advanced upgrades to these buildings include occupancy and motion sensors on all common area lighting, and heat recovery from walk-in freezers and refrigerators. While most of the buildings audited are older, the Old Faithful Visitor Center is a new, LEED Gold certified building, but there are still energy improvements that can be made. These improvements are centered on developing a better understanding of how the energy management systems in the building can be deployed. The Canyon Visitor Education Center, while being recently renovated, has several opportunities to reduce its energy use. The lighting systems used on the education displays do not iii | P a g e utilize many new bulb technologies, the lighting in the building is not considering the natural light in the building, and older HVAC and AHU components could be supplemented with variable frequency drives to improve their energy performance. Being off the grid, the Lamar Buffalo Ranch already had many energy efficiency measures in place. However Lamar does not have an accurate understanding of how much energy it consumes and when it is using this energy. Currently, the amount of energy produced by the solar array must be back calculated based on generator run time and propane use is calculated from propane delivery invoices. These techniques only allow for the accuracy of energy use to be on a yearly time scale. Additional metering would allow for a large increase in accuracy, as well as better inform decisions about expanding renewable energy production and upgrades to the generator systems. The park has a wide variety of water treatment facilities which all make use of large batteries of pumps performing various tasks. Pumps which are regularly throttled by valves, cycled on and off to control flow and output, or which are run intermittently for maintenance reasons could use less energy by installing variable frequency drive control. There are electronic units which control the electricity inputs to a pump and control the flow and output of the pump. When a pump does not have this control, while on, it uses the maximum amount of energy it is rated for. Variable frequency drives reduce the energy demands when pump demands are also reduced. This project also considered how the park can institutionalize sustainable practices in order to improve its existing environmental management strategies. The park’s sustainability efforts are currently led by the park’s Green Team, which is a small interdisciplinary group based in the Mammoth administrative area. Although this group has done many things to improve sustainability in the park, there is still room for improvement. This group should include a wider coalition of park employees in order to make sustainability a park-wide priority and more achievable goal. The Green Team should consider working more closely with the departments in the park, and outside of the park, that plan, design, and maintain the built environment at the park. This includes the planning department, the Denver Service Center, interpretation and exhibit design, as well as maintenance and operations. Developing a broad interdepartmental strategy to improve sustainability at multiple scales will eliminate many of the problems between building design and function that the team noticed at the park. While the primary purpose of this project was to reduce energy demand within the park, the team also developed a guide to help the park consider renewable energy options in order to increase the park’s supply of electricity. Developing renewable energy in the park is a measure to both significantly mitigate and adapt to climate change. There are many limitations on developing renewable energy within the park, such as historic preservation areas and concerns about viewsheds. However, there are also many areas within the park that are zoned as administrative areas that the park should prioritize for these types of projects. Technology such as solar photovoltaics, solar hot water, small wind turbines, and hybrid systems would be appropriate for most administrative areas within the park. However, before moving forward with a renewable energy strategy, the park should either negotiate a better rate for net generation from the electric company or develop energy storage capabilities. While the National Park Service has prioritized off-grid areas for renewable energy development, because it is usually much cheaper than a grid connection, this is not the best strategy to reduce the park’s carbon footprint. Because the local grid is very carbon intensive, in order to more meaningfully address climate change mitigation the park should prioritize renewable energy development in on-grid areas.