Optimizing Radiant Systems for Energy Efficiency and Comfort

Radiant cooling and heating systems provide an opportunity to achieve significant energy savings, peak demand reduction, load shifting, and thermal comfort improvements compared to conventional all-air systems. As a result, application of these systems has increased in recent years, particularly in zero-net-energy (ZNE) and other advanced low-energy buildings. Despite this growth, completed installations to date have demonstrated that controls and operation of radiant systems can be challenging due to a lack of familiarity within the heating, ventilation, and air-conditioning (HVAC) design and operations professions, often involving new concepts (particularly related to the slow response in high thermal mass radiant systems). To achieve the significant reductions in building energy use proposed by California Public Utilities Commission’s (CPUC’s) Energy Efficiency Strategic Plan that all new non-residential buildings be ZNE by 2030, it is critical that new technologies that will play a major role in reaching this goal be applied in an effective manner. This final report describes the results of a comprehensive multi-faceted research project that was undertaken to address these needed enhancements to radiant technology by developing the following: (1) sizing and operation tools (currently unavailable on the market) to provide reliable methods to take full advantage of the radiant systems to provide improved energy performance while maintaining comfortable conditions, (2) energy, cost, and occupant comfort data to provide real world examples of energy efficient, affordable, and comfortable buildings using radiant systems, and (3) Title-24 and ASHRAE Standards advancements to enhance the building industry’s ability to achieve significant energy efficiency goals in California with radiant systems. The research team used a combination of full-scale fundamental laboratory experiments, whole-building energy simulations and simplified tool development, and detailed field studies and control demonstrations to assemble the new information, guidance and tools necessary to help the building industry achieve significant energy efficiency goals for radiant systems in California

Exploitation of dynamic simulation to investigate the effectiveness of the Smart Readiness Indicator: application to the Energy Center building of Turin

To achieve the energy and emissions reduction goals for the building sector, actions are needed to improve energy efficiency and occupants’ wellbeing. To increase the uptake of smart technologies and the awareness upon their benefits, in line with the smart building revolution that is starting, the EPBD recast introduced the Smart Readiness Indicator (SRI) as a tool to evaluate the capability of buildings to easily adapt to both energy systems and occupants’ needs. However, there is a growing interest in studying the SRI features in terms of performance assessment, and, thus, dynamic simulation models can be exploited to better analyze its points of strength and weakness. The Energy Center building of Turin was chosen as case study. By means of EnergyPlus modeling, the current situation was simulated, as well as different scenarios of energy management and control, evaluating to what extent these actions can influence the overall SRI assessment. The analysis allowed to deepen and comment on the effectiveness of the SRI of being a real tool of building behavior assessment, able to link the indicator itself with the energy needs of the building and to understand if and how the indicator is sensible to energy needs variations

The design of an indirect method for the human presence monitoring in the intelligent building

This article describes the design and verification of the indirect method of predicting the course of CO2 concentration (ppm) from the measured temperature variables Tindoor (degrees C) and the relative humidity rH(indoor) (%) and the temperature T-outdoor (degrees C) using the Artificial Neural Network (ANN) with the Bayesian Regulation Method (BRM) for monitoring the presence of people in the individual premises in the Intelligent Administrative Building (IAB) using the PI System SW Tool (PI-Plant Information enterprise information system). The CA (Correlation Analysis), the MSE (Root Mean Squared Error) and the DTW (Dynamic Time Warping) criteria were used to verify and classify the results obtained. Within the proposed method, the LMS adaptive filter algorithm was used to remove the noise of the resulting predicted course. In order to verify the method, two long-term experiments were performed, specifically from February 1 to February 28, 2015, from June 1 to June 28, 2015 and from February 8 to February 14, 2015. For the best results of the trained ANN BRM within the prediction of CO2, the correlation coefficient R for the proposed method was up to 92%. The verification of the proposed method confirmed the possibility to use the presence of people of the monitored IAB premises for monitoring. The designed indirect method of CO2 prediction has potential for reducing the investment and operating costs of the IAB in relation to the reduction of the number of implemented sensors in the IAB within the process of management of operational and technical functions in the IAB. The article also describes the design and implementation of the FEIVISUAL visualization application for mobile devices, which monitors the technological processes in the IAB. This application is optimized for Android devices and is platform independent. The application requires implementation of an application server that communicates with the data server and the application developed. The data of the application developed is obtained from the data storage of the PI System via a PI Web REST API (Application Programming Integration) client.Web of Science8art. no. 2

Data Driven Energy Efficiency Strategies for Commercial Buildings Using Occupancy Information

Most building automation systems operate with settings based on design assumptions with fixed operational schedules and fixed occupancy, when in fact both schedules and occupancy levels vary dynamically. In particular, the heating ventilation and air conditioning (HVAC) system provides a minimum ventilation airflow calculated for the maximum room capacity, when rooms are rarely fully occupied. Energy is wasted by over-supplying and conditioning air that is not required, which also leads to thermal discomfort. In higher educational institutions, where classroom occupancy goals vary from 60% to 80% of their maximum capacity, potential savings are substantial. Existing occupancy and schedule information from academic registration can be integrated with the facility data and the building automation system, allowing dynamic resetting of the controllers. This dissertation provides a methodology to reduce HVAC energy consumption by using occupancy information from the academic registrar. The methodology integrates three energy conservation strategies: shortening schedules, modifying thermostat settings and reducing the minimum airflow. Analysis of the proposed solution includes an economic benefit estimation at a campus level with validation through an experimental study performed on a LEED platinum building. Experiment results achieved an electricity savings of 39% and a natural gas savings of 31% for classrooms’ air conditioning consumption. Extending these savings to the campus level yields 164 MWh of electricity savings per year, 48MMBtu natural gas savings per year, 35.16 MTCO2 of greenhouse gases emissions reduction per year, approximately $20k economic savings per year

A Parametric Approach to Performative-based Design, Case Study: Earth Tube Ventilation

As integrated design becomes more prevalent, new workflows develop in the architectural industry. Rather than the traditional sequential pattern, the knowledge is now being applied in parallel. That is, unlike the old baton passing, the players including the architect, the engineer, the consultant, the contractor, etc. play their role simultaneously. To achieve this, an architectural ecosystem needs a compatible digital information exchange approach; an approach that involves the engineer in the strategic design of systems, increases the chances of more creative, more integrated and higher-performing systems. There are some problems in the current parametric studies such as lack of inclusivity of all building physics facets, lack of validation, and lack of proper visualization in some cases. This dissertation intends to fill in these gaps by proposing a methodology to create a performance model integrated into a popular design tool, Rhinoceros 3D, of a rather rare ventilation system, the Earth Tube Ventilation. The idea is to keep all the simulation pieces in the same place that the 3D modeling happens. The model is further validated using the data from the experiments done on the Aldo Leopold Foundation building located close to Baraboo in Wisconsin. This process can be extended to other aspects of Performative Based Design

DOWNSTREAM BENEFITS OF RETROFITTING AGED DOD BUILDING STOCK WITH A FOCUS ON INCREASING BUILDING ENVELOPE EFFICIENCY

This report examines the downstream benefits of retrofitting current building stock on Department of Defense (DOD) installations. A holistic approach is necessary to achieve the objectives laid out by the executive branch to achieve a net-zero emissions building portfolio by 2045. Current procurement standards address this objective with new construction; however, most buildings within the DOD stock were built ahead of these initiatives and 29% have exceeded their life expectancies. Since this represents a large portion of the DOD building stock, priority should be given to building envelope retrofit projects to reduce the thermal demand in a logically sequenced approach toward net-zero goals. These initial steps are necessary to improve efficiencies that will lead to reduced demand and facilitate downstream investments in alternative and reduced-emissions systems. This report utilized a case study done at NPS that highlights the savings achieved from buildings with tight envelopes and investigated funding streams to achieve these goals.Lieutenant, United States NavyApproved for public release. Distribution is unlimited

hybridGEOTABS project : MPC for controlling the power of the ground by integration

GEOTABS is an acronym for a GEOthermal heat pump combined with a Thermally Activated Building System (TABS). GEOTABS combines the use of geothermal energy, which is an almost limitless and ubiquitous energy source, with radiant heating and cooling systems, which can provide very comfortable conditioning of the indoor space. GEOTABShybrid refers to the integration of GEOTABS with secondary heating and cooling systems and other renewable and residual energy sources (R2ES), offering a huge potential to meet heating and cooling needs in office buildings, elderly care homes, schools and multi-family buildings throughout Europe in a sustainable way. Through the use of Model Predictive Control (MPC), a new control-integrated building design procedure and a readily applicable commercial system solution in GEOTABShybrid, the overall efficiency of heating and cooling will be significantly improved in comparison to current best practice GEOTABS systems and its competitiveness will be strengthened. The present paper is the first of a series that first introduces the hybridGEOTABS project and then specifically focuses on the control-related aspects of the hybridGEOTABS solution, the MPC, providing some interesting insights of its potential development

A Period Examination Through Contemporary Energy Analysis of Kevin Roche’s Fine Arts Center at University of Massachusetts-Amherst

Studies of buildings belonging to a subset of Modernist architecture, Brutalism, have included discussions pertaining to social and architectural history, critical reception, tectonic form and geometry inspirations, material property selections, period technology limitations, and migration of public perceptions. Evaluations of Brutalist buildings’ energy related performances have been restricted to anecdotal observations with particular focus on the building type’s poor thermal performance, a result of the preferred construction method, i.e. monolithic reinforced concrete used as structure, interior finish and exterior finish. A valid criticism, but one that served to dismiss discussion that the possibility of other positive design strategies limiting energy consumption, while simultaneously maintaining occupant comfort, existed in these buildings. The University of Massachusetts-Amherst Fine Arts Center (FAC) designed by Pritzker Prize winning architect Kevin Roche, was the Brutalist building used to develop an evaluation protocol that will serve as a template for energy and/or occupant comfort dissections and evaluations of other Brutalist buildings. A calibrated (ANSI/ASHRAE Standard 140) and validated energy model (DesignBuilder) was programed with all requisites, i.e. geo-position, ordinal orientation, building geometry, envelope materiality, construction details, local weather and climate, program activities, mechanical systems, occupancy schedules, etc. All inputted data was synchronized and consistent with the first year of the building’s occupancy, 1976. Analyses using the DesignBuilder model and an Autodesk Ecotect Analysis model were performed with results relating to thermal performance of the envelope, daylight harvesting, glare control, siting advantage, solar defense via self-shading, material solar absorptance impacts, thermal mass, and wind related strategies documented. Results demonstrated and quantified the inadequacy of the thermal envelope and the positive presence of daylight harvesting, glare control, and solar defense via self-shading. Results also suggest the possibility of material solar absorptance strategies, thermal mass strategies, and wind harvesting strategies. The FAC’s EUI, as determined from the models above and a potential EUI determined from a FAC model inputted with a single energy efficiency measure (improvement of thermal envelope) was compared with EUI data from “CBECS, 2012 Table C5”. This perspective and insight into the building’s reality, within the context of energy performance and occupant comfort, cleared the haze of anecdotal evidence

Rethinking Reiche

Part I of the study examines the differences between two environmental assessment methods for the K‐12 education sector: the United States Green Building Council’s (USGBC) LEED Schools Version 3.0 and the British Research Establishment’s (BRE) BREEAM Education issue 2.0. Credit requirements are compared side‐by‐side and against recommendations from researchers in areas such as acoustics, lighting and indoor environment quality. Strengths in the two schemes and areas for improvement are highlighted, with acknowledgement that each scheme offers components and techniques from which the other could benefit. Part II of the study introduces the Howard C. Reiche Community School in Portland, Maine. Designed as an open‐plan school in the 1970’s this configuration is currently seen as a barrier to teaching and learning in the school which is slated for renovation by the Portland Public School District. Part III of the study looks towards precedents in education which have followed either the LEED or BREEAM assessment methods and Part IV of the study provides a design proposal for the Howard C. Reiche Community School’s renovation