Field Notes Research Update: Spring 2017
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!
Minnesota Department of Commerce awarded a Conservation Applied Research and Development (CARD) grant to CEE’s project team for an 18-month Statewide Natural Gas and Electric Energy Efficiency and Carbon Saving Potential Study. CEE will work with project partners Optimal Energy, Seventhwave, ACEEE, and ESource. The study will inform the state’s Conservation Improvement Program (CIP) decisionmakers regarding which market sectors, geographic areas, utility service territories, end uses, measures, and programs can be targeted to help realize cost-effective energy efficiency potential statewide.
Single-family space heating is among the largest uses of energy in Minnesota and, as few furnaces are replaced before failure, there is immense potential for savings through furnace retrofits. New transport membrane humidifier (TMH) technology developed by the Gas Technology Institute can be added to older, mid-efficiency furnaces to significantly increase their energy efficiency. After completing installation at the final three sites last fall, the project team collected heating-season data throughout the winter and is now collecting some mild-weather baseline data to help with analysis. Based on an initial look at the data, all of the devices improve furnace efficiency and provide some humidification benefit, which is consistent with the results from the first house. The team will complete an analysis of the TMH performance and perform a cost-effectiveness evaluation before submitting a final report later this year.
The energy efficiency and clean energy fields are in the midst of a period of rapid change and growth, and the industry has often struggled to keep pace. This project presented a unique opportunity to test a pre-commercial device in the field and help move the needle forward for energy-efficient emerging technologies. Given that TMH is a brand new technology not yet available commercially, the team naturally encountered some unique challenges that required troubleshooting, and the lessons learned will undoubtedly help influence future design and technical improvements.
The Aquanta smart water heater controller is a device designed for existing water heaters to monitor and control hot water energy use of a standard water heater. This study validates the field performance, cost effectiveness, direct energy savings, and demand-side management capabilities of the Aquanta. In February the project team finished installing the Aquanta and is now currently monitoring all 33 participating sites. During monitoring, the team switches each site between two modes — the first being standard water heater operation and the second being when the controller is on and fully operating. Monitoring will continue at the sites for several months and then the team will finalize data analysis. Project partner Gas Technology Institute will also conduct a user survey to understand the subjective experience of users. As the project team continues to analyze the data, they will pay close attention to survey results to determine whether users notice differences when the Aquanta is operating or not. They will also use the data to determine if and how the device is saving energy.
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 gathered information to improve the operational efficiency of SEDCs in commercial and industrial settings. The project team completed monitoring at all 11 sites and identified significant energy savings potential. There are notable opportunities around air flow management, specifically with cooling. Improving air flow can allow for a higher air temperature in the server room and decrease the need for cooling. The project team also identified an energy reduction of about 60% from simply turning off equipment during non-work hours, and there is an economy of scale with this opportunity, depending on the number of ports and switches hooked up as well as other connected devices such as office phones. In the future, transferring IT services to the cloud is another opportunity that could be incentivized for energy savings.
Throughout the project there was a lot of interest and support from IT staff to implement operational savings opportunities, and there is potential to put their skills to use toward future energy management opportunities. The project team will release a final report in coming months, followed by a webinar on the field work, potential for savings in SEDCs, and recommendations for utility conservation programs.
Commercial energy codes specify design requirements to achieve a minimum level of energy efficiency in new buildings, additions, and renovations. This project provides tools and technical assistance to building design, construction, and code enforcement professionals to help improve compliance with the most commonly neglected and highest-impact energy code requirements. The project includes pilots for both small building design team support and large building city plan reviewers. To date, a total of 28 buildings have engaged with one of the two pilot programs. (Researchers aim to reach a combined total of 36 buildings.) The project team has developed some additional tools and templates to help design teams streamline documentation, and they are currently refining the process for providing comments on code compliance to design teams so that the information is easier to absorb. The next step is to update Minnesota utilities on the project to get their input before finalizing data collection and conducting energy impact analysis. The project team is also collecting control group data for projects that did not receive technical energy code reviews, to be able to compare the benefits of technical review assistance to projects that did not receive program services.
Commercial and hospitality buildings typically have periods of both heavy hot water use and low or no hot water use. Building owners and managers need to ensure that hot water is immediately available during periods of use. This project assesses the effectiveness of new demand control systems to reduce water heating and pumping costs from circulation of hot water in hospitality and commercial venues. The project team installed the demand control system and is currently monitoring six sites. The team encountered several issues that required troubleshooting in the field; some of the issues were easy to resolve while some were more challenging. The next step is to look at the data to determine if these issues are likely to occur with installs in most buildings, or if they were unique to the buildings in this study. It is clear that the device is capable of significantly reducing the run time of recirculation pumps and achieving savings without jeopardizing hot water availability. However, the device works better in some buildings than others so the challenge will be to determine the types of buildings that are a good fit and the characteristics that can be used to identify those buildings.
While high-efficiency condensing boilers have been available in the residential market for many years, consumer acceptance and market penetration is low. One contributing factor is the widespread belief that many installed condensing boilers are not achieving their listed efficiency. CEE is working to characterize existing boilers and determine practical and cost-effective steps to improve performance through both retrocommissioning and improved installation. After completing the first phase to optimize existing boilers, the project team installed seven new boilers using the “quality installation” steps identified in the optimization phase to achieve the listed efficiency. The team monitored throughout the heating season and initial results indicate that the boilers perform as expected, achieving efficiency levels around 90%. It is possible to see how a poor installation could lead to savings below the rated efficiency; however, the field work indicates that overall condensing boilers are meeting high-efficiency standards. The team will analyze the data over the summer in preparation for writing the final report by later this year.
Air source heat pumps (ASHPs) have the potential to improve space heating efficiency and reduce energy costs for houses in cold climates where natural gas is unavailable. This study assesses the efficiency and reliability of new generation ASHPs in Minnesota’s cold climate homes to determine how to best integrate this technology into utility efficiency programs. The project team completed monitoring at all six locations and is currently analyzing the data. Preliminary results show significant savings, with total site energy reductions between 20% and 35%. At sites that used liquid propane as their primary heating source prior to the installation of the ASHPs, ASHPs reduced propane use by 60% to 90%, essentially eliminating the need to refill the propane tank during the heating season when prices vary greatly due to availability and demand. This has the potential to provide significant cost savings for liquid propane homes.
The project team was also able to collect data on the performance of ductless ASHPs; there is evidence that ASHPs can provide heat down to -13⁰F. This result indicates that it may be possible to install ASHPs without backup in multifamily buildings and smaller or high-performance single-family homes in warmer metro areas, eliminating the need for a furnace all together. A final report is due this summer.
The above projects are supported in part by the Minnesota Department of Commerce, Division of Energy Resources, through its Conservation Applied Research and Development (CARD) program, with co-funding by CEE in support of its nonprofit mission to advance research, program design, and knowledge dissemination in the field of energy efficiency.