Field Notes Research Update: Summer 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!
CEE awarded funding for two new research projects
The U.S. Department of Energy's Building Technologies Office has selected a CEE-led research project for funding. CEE's project will explore using network switches to operate and control lighting and plug loads in commercial building office spaces. The team will research and validate energy and cost savings opportunities using existing power over Ethernet (PoE) infrastructure to power and automate lighting, plugs, and HVAC system controls. CEE's research partners will include a PoE consultant, a plug control provider, architecture and engineering firms, commercial real estate company CBRE, and Xcel Energy. **
The Minnesota State Legislature and Governor Mark Dayton approved CEE’s proposed Geotargeted Distributed Clean Energy Initiative in May 2017. The 17-member Legislative-Citizens Commission on Minnesota Resources (LCCMR) previously recommended CEE’s proposal for funding by the legislature. This innovative project will analyze and test the potential for distributed clean energy investments as alternatives to utility capital investments in the distribution system.
Minnesota created the Conservation Improvement Program (CIP) in 2007 to help homes and businesses conserve energy and lessen the need for new utility infrastructure. Today CIP faces a number of challenges. To see continued success, the potential for demand-side energy savings needs to be quantified. Through research and stakeholder collaboration, the project team will clarify Minnesota’s potential for saving energy and lay out key steps to implement recommendations.
The project will calculate technical, economic, and achievable potential. The team is starting with the technical potential, which will determine Minnesota’s efficiency potential using all available technologies and methods regardless of cost and other potential barriers. The economic potential will identify what is actually cost effective while the achievable potential calculations will take into account market barriers. Recent and ongoing changes to Minnesota’s energy system have the potential to impact calculations. For example, with more clean energy on the system — which has zero fuel costs — the marginal benefit of efficiency for reducing fuel usage is decreased.
Since the project launch in March 2017, the project team has focused on finalizing the scope and approach for implementing the study, including a plan for data collection. The team met with dozens of stakeholders from around the state to get a better sense of the important priorities. Based on the initial stakeholder engagement, the team developed a technical memorandum describing the study's approach and data needed to tailor the study to Minnesota specifically, which is available on the project website.
Building envelopes are notoriously leaky with unintended flows between conditioned and unconditioned spaces that result in additional space heating and cooling. Current envelope air sealing methods can produce variable results and require expensive remedial sealing later in construction. This project is evaluating the integration of a new aerosol envelope sealing technology into the home building process.
The project team has identified two Minnesota builders and one California builder to participate in the project. Researchers from CEE and project partner UC Davis performed an initial assessment of each builder’s current practices as well as a demonstration of the aerosol sealing process at one house per builder. The aerosol demonstration for the two Minnesota houses was very successful. For one of the houses, the initial house leakage was approximately 2,200 cfm50 and after 2.5 hours of sealing that was reduced by 84% to 358 cfm50 or 0.64 ACH50. The second house tightness started at 419 cfm50, and with sealing this was reduced by 50% to 209 cfm50 or 0.35 ACH50 — well below passive house standards.
The next step is to review the assessment and demonstration results with each of the builders to determine an implementation strategy to incorporate aerosol sealing into the construction process. During the review period, the project team will focus on pinpointing 1) the stage in the construction process that is best suited for builders to perform aerosol sealing, and 2) any conventional sealing techniques that can be eliminated from the building process with the addition of aerosol sealing. UC Davis has already reviewed the results with the California builder and is preparing to seal the first house in mid-August. CEE’s Minnesota team plans to meet with builders and begin sealing in September.
Manufacturers of through-wall furnace/air conditioner packages have recently introduced high-efficiency, condensing heating products with the potential to deliver significant energy savings in Minnesota multifamily buildings. With funding from CenterPoint Energy, this project will demonstrate the effectiveness of these new packages through market evaluation and case studies of installed units, including evaluations of installations and unit performance. The project team is currently recruiting sites to participate in the case studies, with a goal of three to four sites that have condensing through-wall furnaces and one or two buildings with standard efficiency through-wall furnaces. For each site, the team will perform on-site measurements to determine installed performance, impact on building design, and potential savings and payback of through-wall units. There are also some specific issues to which the team will pay close attention, specifically around condensate and icing.
The project team completed the assessment and evaluation at its first sites and the preliminary results are promising — the unit performed to expected factory standards and there were no problems with occupant comfort, condensate, or icing. In terms of savings, based on a $1,000 incremental equipment cost for the condensing unit and estimated annual savings of 345 therms from heating and 800 kWh from fan use and cooling, the simple payback would be about 2.7 years.
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, and this project sets the stage to realize this potential. Since finalizing all field work in spring 2017, the project team has been completing two guides for optimizing energy efficiency in indoor public pool facilities. The first guide is for pool operations staff, and it includes 14 relatively simple control checks to ensure that the system is operating efficiently. The guide will also provide clear directions on how to address any issues identified through the checks. The second guide is for recommissioning engineers who perform pool energy audits, and it focuses on low-cost energy saving improvements for pool operating equipment, typically control adjustments. The project team is currently getting feedback on the guides from 14 pool operators and engineers, and making improvements before the guide is released publicly.
In addition to work on the guides, the project team has been finalizing energy savings calculations. Preliminary results show significant savings from several site-specific opportunities, with one site saving $5,400 a year as the result of a simple control improvements and another saving $2,500 a year through the use of a pool cover. The energy saving calculations will help to develop recommendations for Minnesota’s Technical Resource Manual (TRM) as well as guidelines for utility program savings calculations.
Minnesota has a goal to generate 10% of electricity from the sun by 2030, which will take Minnesota from just 35 megawatts of solar capacity at the end of 2015 to as much as 6 gigawatts by 2030. Led by the Minnesota Department of Commerce, this project combines stakeholder collaboration with technical analysis to support broad deployment that will help achieve this goal. On the stakeholder engagement, CEE researchers are teaming with project partners Great Plains Institute and Clean Energy Resource Teams. The team has pulled together a technical stakeholder group, which includes representatives from Minnesota utilities, municipal governments, businesses, solar industry representatives, and advocacy groups.
For the second piece of the project, CEE is assisting project partner Clean Power Research in all related modeling efforts for several different phases. The first phase is the solar potential analysis (or “SPA”), which is designed to identify the lowest cost solutions to meet Minnesota’s solar energy deployment goals. The project team is working with stakeholders to identify scenarios for the SPA. Potential scenarios include factors such the baseline years, solar production targets, and technology development scenarios. The SPA is unique in its ability to assess additional technologies that are available to assist in the deployment of solar, such as energy storage, synergy with wind, smart curtailment, geographic dispersion, and load shifting. Preliminary results from the SPA will be available by the end of the year.
Next up is the solar deployment strategies (or “SDS”) phase, which is designed to inform decision-making on different pathways to achieve Minnesota’s near- and long-term solar energy goals. The SDS will be a replicable and living analysis to identify programs, partnerships, and implementation strategies to integrate solar into existing or new implementation.
Commercial building air leakage testing
Oak Ridge National Laboratories (ORNL) collaborated with 3M on the development of 3M’s new Air and Vapor Barrier 3015 — a self-adhered membrane that doesn’t require primer, and is designed for use in new construction to reduce building air leaks and minimize heating and cooling loads. The technology was used in the construction of the new 40,000 sf LifeSource Headquarters building in north Minneapolis. CEE performed a whole building air leakage test of the building for ORNL to determine the effectiveness of the new technology. The test results showed a tightness of 5,400 cfm @75Pa, or a normalized leakage of 0.06 cfm75/sf — making the building one of the tightest buildings ever tested in Minnesota, and over 75% tighter than the U.S. Army Corps requirement of 0.25 cfm75/sf. The results are especially impressive given that the building was not required to meet a whole building tightness requirement and builders did not know there would be a tightness test at the end of construction.
CEE researchers performed a second tightness test on another ORNL research building to further assess the effectiveness of the 3M membrane sealing technology. The results were also promising with a normalized leakage of 0.15 cfm75/sf.
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:
* Projects supported in part by the MN Dept of Commerce, Div of Energy Resources, through its Conservation Applied Research and Development (CARD) program.
** Projects supported in part by the U.S. Department of Energy.