CDH Energy Corporation

Cazenovia, NY, United States

CDH Energy Corporation

Cazenovia, NY, United States
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Domanski P.A.,U.S. National Institute of Standards and Technology | Henderson H.I.,CDH Energy Corporation | Vance Payne W.,U.S. National Institute of Standards and Technology
Refrigeration Science and Technology | Year: 2015

The study analyzed the effect of common installation faults on the cooling performance of a residential, split air conditioner installed in a single-family, slab-on-grade house. We considered five climatic regions in the United States from hot/humid to cold. Through seasonal simulations of the house/air conditioner system, the study found that duct leakage, refrigerant undercharge, undersized refrigerant expansion valve, low indoor airflow, and air conditioner oversizing with non-oversized ductwork have the most potential for causing significant performance degradation and increased seasonal energy consumption. Seasonal energy use can significantly increase even more when the homeowner lowers the thermostat setting to remove excessive indoor humidity caused by certain installation faults.

Yanai R.D.,SUNY College of Environmental Science and Forestry | Tokuchi N.,Kyoto University | Campbell J.L.,U.S. Department of Agriculture | Green M.B.,Plymouth State University | And 12 more authors.
Hydrological Processes | Year: 2015

Uncertainty in the estimation of hydrologic export of solutes has never been fully evaluated at the scale of a small-watershed ecosystem. We used data from the Gomadansan Experimental Forest, Japan, Hubbard Brook Experimental Forest, USA, and Coweeta Hydrologic Laboratory, USA, to evaluate many sources of uncertainty, including the precision and accuracy of measurements, selection of models, and spatial and temporal variation. Uncertainty in the analysis of stream chemistry samples was generally small but could be large in relative terms for solutes near detection limits, as is common for ammonium and phosphate in forested catchments. Instantaneous flow deviated from the theoretical curve relating height to discharge by up to 10% at Hubbard Brook, but the resulting corrections to the theoretical curve generally amounted to <0.5% of annual flows. Calibrations were limited to low flows; uncertainties at high flows were not evaluated because of the difficulties in performing calibrations during events. However, high flows likely contribute more uncertainty to annual flows because of the greater volume of water that is exported during these events. Uncertainty in catchment area was as much as 5%, based on a comparison of digital elevation maps with ground surveys. Three different interpolation methods are used at the three sites to combine periodic chemistry samples with streamflow to calculate fluxes. The three methods differed by <5% in annual export calculations for calcium, but up to 12% for nitrate exports, when applied to a stream at Hubbard Brook for 1997-2008; nitrate has higher weekly variation at this site. Natural variation was larger than most other sources of uncertainty. Specifically, coefficients of variation across streams or across years, within site, for runoff and weighted annual concentrations of calcium, magnesium, potassium, sodium, sulphate, chloride, and silicate ranged from 5 to 50% and were even higher for nitrate. Uncertainty analysis can be used to guide efforts to improve confidence in estimated stream fluxes and also to optimize design of monitoring programmes. © 2014 The Authors. Hydrological Processes published John Wiley & Sons, Ltd.

Henderson Jr. H.I.,CDH Energy Corporation | Rudd A.,ABT Systems LLC
ASHRAE Transactions | Year: 2014

Conventional air conditioners have traditionally been deemed adequate for controlling space humidity levels in residential applications. However, as homes in humid climates have become more energy efficient, there is evidence that relative humidity levels in homes have been increasing (Rudd and Henderson 2007). This implies that sensible heat gains to the building have been reduced more than moisture loads, leaving a mix of latent and sensible loads that is poorly matched to the sensible heat ratio of conventional air-conditioning systems. Furthermore, requirements to provide mechanical ventilation per ASHRAE Standard 62.2 have affected space humidity levels in a typical home. A detailed simulation model was developed in TRNSYS to accurately predict energy use and space humidity levels for the wide variety of space-conditioning systems. The analysis considered various building efficiency levels, mechanical ventilation options, equipment performance and configuration options, and climates. The hours when humidity is a concern (e.g. over 60% rh) generally occur in the winter and swing seasons. When mechanical ventilation is added to an older standard efficiency house, the number of high humidity hours tends to increase slightly. As the home efficiency level continues to increase to current practice and to slightly better than current codes, the number of high humidity hours generally decreases. However, for very high efficiency houses, where the space conditioning air distribution ducts are moved from the attic to inside the conditioned space, the high humidity hours tend to increase again. Air conditioner enhancements that lower the airflow and allow overcooling at high humidity times generally cut the number of annual hours over 60% rh by half when the activation setpoint was 50% rh. However, precise humidity control (to maintain a setpoint) requires a separate dehu-midifier or an air-conditioner system with full condensing reheat to provide dehumidification without sensible cooling. The operating cost for full humidity control is typically 10%-30% greater than a conventional cooling system without explicit humidity control, depending on the dehumidification system and the relative humidity control setpoint. © 2014 ASHRAE.

Dentz J.,The Levy Partnership Inc | Varshney K.,The Levy Partnership Inc | Henderson H.,CDH Energy Corporation
Energy Efficiency | Year: 2014

In this article, we quantify overheating in a sample of hydronically and steam-heated apartment buildings located in New York City, NY. Data have been collected from the archives of companies that provide energy management systems (EMS) to multifamily buildings in the Northeast. Overheating was found in all 18 buildings: the overall average temperature of all buildings was well above 21.1 °C (70 °F) when the EMSs were not in operation, leaving the boilers operate on outdoor reset control, the dominant boiler control type for multifamily buildings. EMS operation is intended to depress overheating. In 15 of the 18 buildings, average temperatures in 100 % of the apartments when EMSs were not in operation were above 21.1 °C (70 °F) [ranging from 21.5 (70.7 °F) to 30.8 °C (87.4 °F)]. In the remaining three buildings, average temperatures in 88 % of apartments were also above 21.1 °C (70 °F) [ranging from 21.5 (70.3 °F) to 29.6 °C (85.2 °F)]. On the other hand, when the EMSs were activated, in seven of 18 buildings, average temperatures in 100 % of the apartments were above 21.1 °C (70 °F) [ranging from 21.5 °C (70.3 °F) to 27.3 °C (81.1 °F)]. In the remaining 11 buildings, average temperatures in 67 % of the apartments were above 21.1 °C (70 °F) [ranging from 21.1 °C (70 °F) to 27.3 °C (81.2 °F)]. Based on this analysis, the estimated average increase in annual space heating energy cost for these buildings due to overheating is approximately 18.6 % when the EMS is off, compared to a baseline average temperature of 21.1 °C (70 °F) all the time. In addition, we employed boiler control systems in three separate hydronically heated buildings that offer aggressive temperature setbacks and one that supplies heat based on apartment temperatures in addition to outdoor temperatures. Results show that after implementing control techniques, heating energy consumption in these three buildings was reduced by 12.7 % to 18.4 % and averaged 16.3 %. © 2013 Springer Science+Business Media Dordrecht.

Domanski P.A.,U.S. National Institute of Standards and Technology | Henderson H.,CDH Energy Corporation | Payne W.V.,U.S. National Institute of Standards and Technology
Applied Thermal Engineering | Year: 2015

Abstract This study seeks to develop an understanding of the effect of commissioning common faults on the energy consumption of an air-to-air heat pump installed in a single-family, slab-on-grade residential house. Through annual simulations of the house/heat pump system, the study found that duct leakage, refrigerant undercharge, oversized heat pump with nominal ductwork, low indoor airflow due to undersized ductwork, and refrigerant overcharge have the most potential for causing significant performance degradation and increased annual energy consumption. Depending on the faults involved, the effects of simultaneous faults were found to be additive, little changed relative to the single fault condition, or well-beyond additive. A significant increase in annual energy use can be caused by lowering the thermostat setting in the cooling mode to improve indoor comfort in cases of excessive indoor humidity levels due to installation faults.

Doebber I.R.,National Renewable Energy Laboratory | Lilya D.,DC Engineering | Henderson H.I.,CDH Energy Corporation
ASHRAE Transactions | Year: 2013

Supermarkets installing combined heat and power (CHP) systems are looking to reduce utility electric consumption while applying the thermal output to offset service hot water, space heating, refrigeration subcooling, desiccant dehumidification and space cooling via an absorption chiller. Unfortunately, monitoring of supermarket CHP systems has shown that while the electric power was successfully applied, the waste heat was not properly utilized. Comparatively, CHP projects are highly successful in industry and manufacturing settings since the thermal load profiles are well understood and remain relatively constant throughout the year. For supermarket CHP systems to make economic sense and reduce carbon emissions, the thermal output needs to be nearly fully utilized throughout the year. The following paper summarizes the variation of thermal demands of stores in San Diego, CA and Boston, MA, which apply fuel cell waste heat to different thermal loads; two combined big box/grocery stores in Arkansas with no CHP system; and a supermarket in Raleigh, NC also with no CHP system. These concrete examples also provide insight into how thermal loads change when new stores or deep-dive retrofits implement increased on-site food preparation, secondary refrigeration systems, doors on medium temperature refrigerated display cases, and reduced lighting power densities. Each section is dedicated to a separate thermal demand. The authors use a combination of field monitored data and modeling to discuss in detail how to effectively apply CHP thermal output, focusing on how to maintain sufficient temperature differences (heat quality), attack persistent and large loads (heat quantity), and address fundamental design considerations. © 2013 ASHRAE.

Meng Z.,Syracuse University | Pelken M.,Syracuse University | Zhang J.,Syracuse University | Rice D.,Syracuse University | And 4 more authors.
Indoor Air 2014 - 13th International Conference on Indoor Air Quality and Climate | Year: 2014

Buildings continue to become more complex and must meet stringent energy efficiency, indoor environmental quality (IEQ), and other project requirements which often have competing goals. Green building design calls for integrated and coordinated design process. Although software exists for either performance simulation or planning, none integrates both functions to support multi-disciplinary design team coordination and integrated energy and IEQ analysis from early to final design stages. This study explores methodologies, and develops a software framework to address this knowledge gap. An example is given to show how the software can be used to assist collaborative and integrated design for complex green building design.

Zhang J.,Syracuse University | Michael Pelken P.,Syracuse University | Chen Y.,Syracuse University | Rice D.J.,Syracuse University | And 6 more authors.
Building Simulation | Year: 2013

The "Virtual Design Studio (VDS)" is a software platform for integrated, coordinated and optimized design of building energy and environmental systems. It is intended to assist management, architectural and systems design teams throughout the early to detailed building design stages as analyzed in Part 1 (DOI: 10.1007/s12273-013-0110-2). This paper presents an overview of the VDS design and method of software implementation, including system composition, architecture, graphical user interface (GUI), and simulation solver integration. A VDS user workflow is also illustrated with a simplified design example. © 2013 Tsinghua University Press and Springer-Verlag Berlin Heidelberg.

Michael Pelken P.,Syracuse University | Zhang J.,Syracuse University | Chen Y.,Syracuse University | Rice D.J.,Syracuse University | And 6 more authors.
Building Simulation | Year: 2013

The "Virtual Design Studio (VDS)" is a software platform currently under development in support of an integrated, coordinated and optimized design of buildings and their energy and environmental systems. It is intended to assist collaborating architects, engineers and project management team members throughout from the early phases to the detailed building design development. The platform helps to facilitate the workflow and the processing of information in combination with appropriate, task-based performance simulation tools as further analyzed in Part 2 of this study (DOI: 10.1007/s12273-013-0111-1). The present paper summarizes how VDS relates to the building design process and its typical project stages, performance-based design considerations and respective performance optimization strategies. It outlines the methodology and scope for the organization, implementation and respective requirements for the VDS platform development based on the interdisciplinary design needs. Part 2 will present the methodology for the systems integration and software implementation of VDS. © 2013 Tsinghua University Press and Springer-Verlag Berlin Heidelberg.

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