Field Notes Research Update — August 2015
Center for Energy and Environment conducts technology and market assessments to identify tomorrow’s best clean energy strategies. For over 30 years, our research staff has produced technical studies on building science, mechanical system performance, and program policy design.
This blog post is taken from our Field Notes newsletter which features updates on CEE's research projects. Sign up for Field Notes to get this information in your inbox!
Summer 2015 Research Updates:
Even when ducts are entirely within a building’s enclosure, air leakage from ducts wastes energy by increasing fan power and discarding conditioned air. This research characterized leakage in large commercial and institutional building duct systems to improve air sealing screening and diagnostic procedures.
The project team has completed all field work and submitted the final report to the Minnesota Department of Commerce, Division of Energy Resources, for review. This final report includes lessons learned to clarify conclusions that will be useful to utility program staff, contractors, and future researchers. Initial findings indicate that Aeroseal, a patented sealing method, makes it possible to tightly seal duct work through retrofits. Thanks in part to this method, the overall cost was much lower than anticipated. Staff are currently developing plans to expand the project’s scope to apply guidelines and expected savings to a new set of buildings to better understand both how to make retrofit duct sealing cost-effective and how Aeroseal would work on larger, leakier duct systems than were initially tested. CEE expects to publish the final report later this year, after the review is completed. Visit the project page.
Commercial and hospitality buildings typically have periods of both heavy hot water use and low or no hot water use, and building owners and managers typically ensure that hot water is immediately available at all times. This project assesses the effectiveness of new demand control systems to reduce pumping and water heating costs in hospitality and commercial venues. While past research has shown that reducing the run time of recirculation pumps does achieve savings, systems have failed to achieve these savings while maintaining hot water availability.
A big question with this project is whether controls allow for a quick enough reaction to demand to maintain required performance. Since January, researchers have been working to characterize existing systems and determine the potential for this technology to save energy in Minnesota buildings. With initial characterization nearly complete, the team is beginning the first phase of short-term monitoring in seven different buildings and working to recruit additional buildings. In October, the team will begin the project’s second phase by installing demand control systems in buildings, and monitoring and comparing results to baseline existing systems to determine the savings potential. Initial findings indicate that it is possible to easily characterize the savings potential for buildings without extensive data monitoring and collection. This, combined with the low cost of the retrofit, could make this technology a strong candidate for utility conservation programs. Visit the project page.
Energy recovery ventilation (ERV) systems have the ability to reduce the heating and cooling energy associated with outside air conditioning by over 65%. This field research identifies common issues affecting the performance of ERV systems in Minnesota buildings and develops protocols to optimize their performance.
The project team learned a lot during the project’s first phase, and has been using that information to work with sites to implement recommendations for improving system operations. This has been more challenging and time-consuming than expected because unique, site-specific issues have impacted the performance of each ERV system. ERV systems are interconnected with many other building systems, so it can be difficult to understand how these systems work together. The team is synthesizing information to develop a broader understanding of potential issues with ERV systems and to better target key problems. CEE will likely be ready to disseminate preliminary conclusions by the end of the year. Visit the project page.
Small embedded data centers (SEDCs) are among the fastest growing users of electrical energy in commercial buildings. Through field studies and stakeholder engagement, this project gathers information to improve the operational efficiency of SEDCs in commercial and industrial settings. Since January 2015, researchers have completed a characterization phase that included a literature review of past studies and an electronic survey distributed to IT managers across Minnesota. The survey yielded 82 responses, and results indicated a strong potential for savings opportunities. It also confirmed that SEDC energy consumption is not a high priority for most IT managers, revealing this to be an underserved market that could benefit greatly from utility incentives to adopt energy-efficiency measures.
For the project’s second phase, the research team is working with Packet Power, a Twin Cities company that manufactures affordable, commercially available equipment to monitor power usage in data centers. Field monitoring using Packet Power’s equipment will begin in the fall to better understand usage patterns, server utilization, and savings potential. The team is currently working on recruiting buildings to participate in this phase. Visit the project page.
Although the market share of condensing boilers has increased dramatically over the last several years, many newly installed condensing boilers only achieve a fraction of their expected energy savings. This field research quantifies how operating conditions impact the installed energy efficiency of condensing boilers and determines the potential for optimization through low-cost upgrades.
Since field monitoring wrapped up last fall, the project team has been analyzing the efficiencies at which the boilers were found to be operating, identifying measures to provide energy savings, and calculating potential savings. Research indicates opportunities to improve boilers’ efficiency that would involve simple reprogramming of controls. The team is also looking into feedback through an online survey of 19 trade professionals, and hopes to gain a better understanding of installation issues and perspective about how best to address these issues. Based on survey responses, it is clear that this issue is a big concern for many buildings in Minnesota and nationally. A final report is due out in late fall 2015. Visit the project page.
The energy use intensity for indoor pool areas is three times higher than most other areas within a building. Indoor pool facilities are prime candidates for energy savings through improved recommissioning and operator training. This project sets the stage for realizing this potential. In 2015 project staff selected and started monitoring six sites in buildings that are representative of those typically containing public pools — two schools, two fitness centers, one multifamily building, and one hotel.
Monitoring will continue until the spring 2016. During this time staff will establish a baseline of current operating conditions, work with contractors and operators to implement improvements, and continue monitoring to collect data on the impact of the improvements in both warm and cold weather conditions. So far researchers have encountered a range of problems with dehumidification controls, as many do not operate as manufacturers intended and have communication difficulties with building automation systems. Most recommended retrofits range from simple control adjustments to much more expensive and complicated changes, but do not require major new equipment installations. The project team will use research findings to develop guides for energy-efficient operation and recommissioning of indoor swimming pool facilities. Visit the project page.
See all CEE research project pages
These projects are supported in part by a grant from the Minnesota Department of Commerce, Division of Energy Resources through the Conservation Applied Research and Development (CARD) program. And with co-funding by CEE in support of its nonprofit mission to advance research, knowledge dissemination, and program design in the field of energy efficiency.