Project List by Type

Schlitz Audubon Nature Center

In a collaborative effort with the University of Wisconsin Milwaukee, we installed environmental monitoring equipment (CO2, temperature, humidity, wind speed and direction) and benchmarked CONTAM simulation results against measured data to assess the appropriateness of modeling natural ventilation with multi-zone bulk air flow modeling tools. The results of this study have been published and are referenced in the publications section of our website.

NIST Contam

Working with the National Institute of Standards and Technology (NIST), we coupled the CONTAM bulk airflow modeling tool with TRNSYS to provide combined airflow and thermal analyses. The combined modeling tool was then used to analyze the effect of infiltration rates on building energy consumption for typical office buildings in the United States. The results of this study have been published and are referenced in the publications section of our website.

NIST ASHRAE 90.1

We used the combined TRNSYS/CONTAM modeling tool to analyze the effect of improved airtightness in typical office frame and masonry construction on the overall energy consumption of the buildings in five climates typical of the US. The study was done to advise the ASHRAE 90.1 Envelope Subcommittee on the possibility of updating the required airtightness of buildings. The results of this study have been published and are are referenced in the publications section of our website.

Washington University Central Plant

Analysis of multiple configurations and optimization of a central plant heating and cooling system for Washington University in St. Louis featuring liquid desiccant dehumidifiers, PV/thermal solar collection, ground thermal storage, chilled water & hot water storage and co-generation. This project went through several design iterations and our task was to optimize the sequencing of the numerous sources and sinks in order to minimize the life cycle cost of the system over 20 years of operation.

York University Central Plant

Analysis, configuration, and optimization of an 11,000 ton chilled water system in Toronto in consideration for an innovative cold-storage system. Calibration of modeled thermal loads to measured building loads was followed by the creation of 8 unique system configurations for analysis. Optimization of several of the more promising configurations is currently undergoing.

Miami University of Ohio Central Plant

Two separate central plants were investigated at Miami University. Both plants were equipped with a hot water loop (steam/HW heat exchangers in one and HW boilers in the other), heat recovery chillers, and standard electric chillers. Optimal sequencing and control of the chillers and heating systems was investigated as well as an analysis of whether the heat recovery chillers should be upgraded to higher efficiency models.

Caterpillar Central Plant

The central plant in this project consisted of standard electric chillers, hot-water fired absorption chillers, boilers, and a gas gen-set. Optimal sequencing and control of the plant was investigated with the primary intent being to decide when (and how hard) the gen-set should be run factoring its waste heat recovery impact on the balance of the plant.

Beijing Solar Seasonal Storage

Following on the heels of more than a dozen unique solar seasonal storage analysis projects with NRCan over the last few years, this project is in the feasibility stage to see whether the solar resource, thermal load, and economics of a potential solar district heating system in Beijing warrant a more detailed design investigation.

ORNL Co-Gen

In a project sponsored by Oak Ridge National Laboratory, TESS developed a commercial library of over 50 new TRNSYS components modeling various pieces of equipment commonly used in the CoGeneration / Combined Heat and Power field. Components include heat recovery steam generators, feedwater heaters, steam turbines, air compressors, generators, flash tanks, plus many more. These component models are used by ORNL personnel to determine the feasibility of large-scale CHP retrofit projects on Federal facilities.

Reinbold

As is the case in many of our projects, we were called in to model a complex heating and cooling system when other programs/firms were unable to adequately model the system. In this project, we modeled a detailed ground-source heat pump system for a commercial project where the heat pumps are controlled to simultaneously provide both heated and cooled water for building heating and cooling systems, the domestic hot water system, and pre-treatment of ventilation air.

Sylvan Lake

In an ongoing modeling project, we have been asked to validate the design of an innovative hybrid HVAC system installed on a resort complex in Alberta Canada that includes solar thermal collectors, short-term liquid thermal storage tanks, water-to-water heat pumps, backup boilers, and a horizontal ground heat exchanger located under the parking garage floor.

Conservatek

TESS was asked to assess the radiative and convective heat exchange phenomena of high temperature industrial clinker contained in a geodesic dome that is subject to environmental conditions. Of particular concern was whether temperatures critical to the structural integrity of the dome would be reached on high solar, low wind days when the dome was near capacity.

IEA Slabs

Under International Energy Agency Task 34/43, models for 3-dimensional slab-on-grade heat transfer were compared against an analytical solution and against each other for a series of test cases. After confirming our TRNSYS model compares favorably to the analytical solution (<1% difference) and demonstrating the flexibility and robustness of our model, the IEA technical manages pronounced our model as one of the “reference standards” for slab-on-grade heat transfer against which other models can be judged. Our model was then repeatedly exercised to help refine the test specifications for later IEA 34/43 submittals. This slab-on-grade model has been used as the basis for recent developments in radiant floor modeling, basement modeling, horizontal ground heat exchanger modeling and buried pipe modeling.

Fort Polk

In support of Oak Ridge National Laboratory, we carried out a host of modeling and engineering activities at Fort Polk Joint Readiness Training Center in Louisiana. The major energy savings performance contract retrofit the heating, cooling and hot water systems for over 4000 military housing units. To date it represents the world’s largest vertical-bore geothermal heat pump project in the world with over 700 miles of installed buried pipe. The major tasks involved calibrating a simulation model to detailed data on one of the units, predicting the performance of 200 homes on one of the electrical feeders after the retrofit, and hosting a published “shoot-out” of the existing commercial ground heat exchanger design programs using TRNSYS as the benchmark.

Detailed Project Summary.

Daniel Boone High School

In a project with ORNL and the Tennessee Valley Authority (TVA), we carried out a calibration exercise in which every major HVAC energy-consuming device (every heat pump, pump, boiler, fans etc.) in every room in the school was compared to its matching counterpart in a detailed simulation model. The project aimed to prove that detailed models provide an excellent estimate of the performance of heat pump systems in schools and can be used in the early design stages of school projects to demonstrate the potential savings of these types of systems. Numerous technical papers have been written on this project and are listed in the publications section of our website.

Oceana Naval Air Station / Little Creek Naval Amphibious Base

Under the auspices of the Federal Energy Management Program’s (FEMP) Super-Energy Savings Performance Contract initiative, we were asked to predict the post-retrofit energy performance of 13 buildings at Oceana Naval Air Station and Little Creek Naval Amphibious Base in Norfolk, Virginia. Armed with detailed simulation models that were firstly calibrated to measured utility data, the proposed retrofits (GSHP systems) were performed in the simulation model and the predicted results from the simulations were used to demonstrate the energy savings potential to both the Navy and to the winning performance-contractor.

Integrated Heat Pump (IHP)

Integrating ORNL’s integrated heat pump model (HPDM) into the TRNSYS software, we were asked to analyze the annual performance of IHP systems for five unique climates in the US. IHP systems combine heating, cooling, domestic hot water production, humidification and ventilation in a single packaged unit and may provide significant energy savings for residential projects attempting to achieve “zero net energy”.

Duckworth

In cooperation with Atelier Ten, we carried out an analysis of several innovative HVAC systems for a large occasional use residence in Aspen, Colorado. Strategies were investigated for making use of building thermal mass, high amounts of available solar energy, cool summer nights, architectural shading features, and radiant slabs in an effort to reduce energy consumption.

Milwaukee Public Market

A public market / grocery store proposed for downtown Milwaukee presented large amounts of glass to an un-shaded, western exposure. In support of the project development team, we aided in assessing the performance of architectural shading devices (overhangs and operable louvers) to mitigate late afternoon solar loads on the merchants within the building.

Schlitz Audubon Nature Center

In addition to carrying out an experimental validation of natural ventilation systems simulation models after the Schlitz Audubon Nature Center (SANC) was occupied, we acted as an advisor during the SANC building’s LEED™ submittal process and carried out assessment of the geothermal bore field’s thermal storage capacity.

Aldo Leopold Legacy Center

Recognizing the benefits of energy modeling, the Aldo Leopold project team brought us in at the very start of this LEED™ Platinum (anticipated) building project to use simulation to inform the design of, not only the highly efficient building, but also its ancillary systems such as earth ducts, natural ventilation system controls, radiant heating/cooling slabs, and ground source heat pump systems.

Detailed Project Summary.

Navy Hybrid

In a project sponsored by Oak Ridge National Laboratory, we optimized the design, configuration, and controls for a cooling-dominated hybrid ground source heat pump application for an office building at Fort Polk Joint Readiness Training Center in Louisiana. The results and methodology from this analysis are currently being utilized in a joint ASHRAE-sponsored research project with the University of Wisconsin (ASHRAE TRP-1384)

Campus Hybrid

Called in when the first cost of a conventional ground source heat pump system proved too costly, we developed a software tool that allows the building owner, engineering firm, architects, and construction firm to explore the costs (both first cost and operating costs) and performance trade-offs of a hybrid ground-source heat pump system for a large retirement community project.

Eastern Village Co-Housing

In support of the project architects, we carried out LEED™ energy modeling on an older office building that was converted into luxury condominiums in Silver Spring, Maryland. The building makes use of architectural shading devices and geothermal heat pumps to achieve its energy savings and was awarded both a LEED™ Silver rating and the 2006 National Association of Home Builders (NAHB) Sustainable Building of the Year award.

Aldo Leopold Legacy Center

In early 2007 and after using simulation to significantly inform the design process, we carried out the LEED™ 2.1 energy modeling for the Aldo Leopold Legacy Center project in Baraboo, WI. The stated LEED™ goal for the building was a Platinum rating. Truly using simulation to inform design in this case, the ALF Legacy Center received all 10 available energy credits and was awarded a total of 61 (of 69 possible) LEED™ points, the highest number awarded at the time of its certification.

Detailed Project Summary.

Schlitz Audubon Nature Center

Working as part of a large project team on an innovative building, we simulated the geothermal bore field and heat pump systems as well as acted in an advisory role to the primary LEED™ energy modeling team working on the Schlitz Audubon Nature Center submittal. The building was awarded a Gold rating.

O’Neil Residence

This project sought to drastically reduce the need for mechanical heating and cooling in a Philadelphia based single family residence and then to evaluate potential space conditioning systems to meet those reduced requirements. After evaluating the envelope and passive solar design of the residence, we modeled a ground coupled heat pump system, a furnace / air conditioner system assisted by both a solar wall and an earth duct, a boiler-heated, water-based radiant floor system, and a solar wall heated sub-floor hypocaust system. The O’Neil residence was the first LEED™ for Homes Gold certified project in the United States.

Wetlands

Developed for an engineering firm specializing in wetland technologies, this component models the thermal behavior of a porous media filled rectangular storage tank that is repeatedly filled and drained of liquid. The tank may be thermally stratified, may be partially buried (interacting with the surrounding soil), may have solar on its top and side surfaces, and may be actively ventilated above the liquid level. Conductive, convective, and evaporative heat transfer phenomena are accounted for in the model.

PV/Thermal

With cooperation from the National Renewable Energy Laboratory we developed a series of first-principles based combined photovoltaic / thermal components for use with TRNSYS. Where these models depart from many other PV/thermal approaches is that they can be used to assess the performance of photovoltaics that are an integral part of a building façade, in which case, the inefficiencies of the PV cause artificially elevated façade temperatures - which in turn affect the thermal performance of the building skin. These models are currently being utilized by an International Energy Agency team tasked to study PV/T systems.

TRNSYS/TESS Libs

The TRNSYS Developers Group contracts us to carry out ongoing revisions and enhancements of the TRNSYS source code. Additionally, through our consulting work we have the opportunity to write new component models for TRNSYS. Since 2000, these models have been cleaned up and documented and are offered to the public through a series of 13 libraries that are available for commercial purchase in fields that include HVAC, Hydronics, Thermal Storage, Refrigeration, Solar Collection Systems, PhotoVoltaics, Ground Heat Transfer, Controls, Loads & Structures, and Optimization among others.

Stand Alone Hybrid Power Generation System

Many of the intricacies of developing and deploying hybrid power generation systems that include photovoltaics, wind turbines, hydrogen fuel cells, electrolyzers, batteries and backup generators center on the overall control (or dispatching) strategy. We spent over a year developing TRNSYS models of numerous innovative control strategies for such systems. The models were built into TRNSYS distributable applications and disseminated to clients such that they can study various control scenarios and configurations.

UEC BiPV

Under a state-sponsored energy program, we collected performance data at Milwaukee’s Urban Ecology Center (UEC) on the incident solar radiation and electrical power output of the PV arrays installed on the building. This data was then used to help compare the predictions from different PV models available in energy modeling tools as well as to spot check that the installation was working as designed.

RENEWisc

Under the guidelines of a State of Wisconsin energy project, we developed a freely distributable software tool with an intuitive graphical front end that assesses the potential energy savings for buildings employing any combination of photovoltaics, wind turbines, a one or two tank solar domestic water heating system, and / or a fuel cell.

Stand Alone Hybrid Power Generation System

Numerous tools exist for assessing the performance of individual power generation systems such as photovoltaics, fuel cells, and wind turbines. However, when such technologies are combined together, the resulting system is often very highly customized and can no longer be modeled using standard tools. We have carried out a number of projects centering on the assessment of system performance for systems that innovatively combine multiple renewable energy technologies for either grid tied backup power systems or entirely stand-alone power systems.

NREL SDHW Tool

In a project sponsored by the U.S. Government’s Building America Program, and with the cooperation of the National Renewable Energy Laboratory, we developed a freely-distributable software tool that predicts the annual energy savings for one and two-tank solar domestic hot water systems equipped with various collector technologies. The program may be downloaded by clicking here.

EFLH

For AHRAE Research Project 1120-TRP, we developed a freely-distributable software tool that predicts the equivalent full-load hours for buildings equipped with ground source heat pump systems. The program may be obtained by writing to us and requesting a version of the software.

RREAL Solar Air Heat Analyzer

For the Rural Renewable Energy Alliance (RREAL) of Pine River, MN, TESS created a stand-alone, TRNSYS based (TRNSED) application for their solar air heating collectors. RREAL not only manufactures the solar air collectors, but they also strive to deliver solar heat for low-income families as a viable solution to fuel poverty. The TRNSED application, also sponsored by Clean Energy Resource Teams, is a very useful tool for determining the best option for solar air heating. The program may be downloaded by clicking here.

Drake Landing Solar Community

As the lead energy modeling firm for a community-sized solar district heating project that is attempting to be the first of its kind in the world to deliver 90+% of the heating energy from the sun, we developed a detailed simulation of the entire project including the collection loop, the distribution loop, the energy storage loop, and the controls in order to predict the performance of the development over its proposed 50-year lifetime. Through the use of optimization techniques, we helped re-design the system to greatly increase the efficiency of the project while still maintaining the project within cost constraints.

Detailed Project Summary.

Vulcan Solar

The town of Vulcan, Alberta, Canada is considering a project to implement a mammoth solar district heating and storage system, combined with an auxiliary biomass boiler, to provide heat to the homes in the community. We were asked to model the proposed system in order to help size the various components (pit storage, collector arrays, auxiliary boilers, etc.) and to predict the performance of the system over its lifetime.

NREL SDHW Tool

In a project sponsored by the U.S. Government’s Building America Program, and with the cooperation of the National Renewable Energy Laboratory, we developed a freely-distributable software tool that predicts the annual energy savings for one and two-tank solar domestic hot water systems equipped with various collector technologies. The program may be downloaded by clicking here.

Monkey Astronaut Retirement Home

In a project sponsored by TCT Solar, we were tasked to project the energy savings potential of multiple Integral Collector Storage (ICS) solar collectors mounted on the roofs of a monkey astronaut retirement home in Florida. Seems that cleaning up after monkeys requires a lot of water…

NREL Un-Glazed

In a project sponsored by the National Renewable Energy Laboratory, we developed a software tool that predicts the annual energy savings for residential un-glazed solar collector systems. These systems can be used to heat water during the sunlit hours and reject energy from the homes during the night time hours in the cooling season.

Power Roof

During the development phase of the Solar Power Roof collection system (a solar collector that utilizes a fixed collector and a tracking receiver), we supported Duke Solar in their attempts to find commercial markets for their innovative design. Power generation systems, solar cooling systems, solar heating systems, and desalination projects were all analyzed for their energy and cost-savings potential.

Solar Absorption

Over the past several years we have modeled solar absorption cooling systems for both the National Renewable Energy Laboratory and for a project sponsored by the California Energy Commission. The benefits of storage were analyzed and several system configurations were studied in order to determine the system with the optimal life cycle cost.

Solar Adsorption

In a project with Natural Resources Canada, we modeled a proposed commercial heating and cooling system that utilized an adsorption chiller to supplement the back-up electric chiller. A flat-plate solar collector array is used to charge a short-term storage tank which has the dual purposes of providing hot water to the heating and hot water systems as well as providing source energy for the adsorption system.

SRCC OG-300 Ratings Engine

Starting in 2017, the Solar Rating and Certification Corporation's (SRCC) OG-300 and OG-100 ratings for solar domestic hot water systems will use a custom TRNSYS-based engine written by TESS. TESS will be responsible for creating and maintaining the ratings as well as authoring and maintaining an entire suite of custom models and application programs for SRCC. We will also be routinely calibrating our models to measured test lab data provided for new collectors and collectors that are being re-certified.

CSI Thermal Ratings Tool

Since 2015, the CSI-Thermal web tools for Commercial Solar Domestic Hot Water Systems and Commercial Solar-Heated Pools have relied on a custom TRNSYS engine built by TESS. The predictions from our simulation engine lead directly to consumer rebates based on the estimated annual performance - with millions of dollars of rebates having already been given out since program inception. In 2016 the California Public Utility Commission funded a project to measure the real-world performance of dozens of commercial pools and SDHW systems that received rebates and compare the results against the model predictions. Early results have shown excellent agreement between the measured data and the model predictions.