Historically, the rising cost of energy has been a huge driver for data center energy efficiency, and the contribution of this consumption to climate change is ever more evident. As the industry begins to look beyond energy consumption, it has become aware that environmental impact derives not just from energy consumption, but also from our use of natural resources. To ensure optimization measures do not cause a burden shift, these interdependent issues should not be considered in isolation. Data centers consume energy to power and cool IT equipment. Current optimization efforts largely focus on the operation of cooling technologies.

The Thermosyphon Cooler Hybrid System (TCHS) integrates the control of a dry heat rejection device, the Thermosyphon Cooler (TSC), with an open cooling tower. This new heat rejection system embraces a “smart use of water,” using evaporative cooling when it is most advantageous and then saving water and modulating towards increased dry sensible cooling as system operations and ambient weather conditions permit. Johnson Controls partnered with the National Renewable Energy Laboratory (NREL) along with Sandia National Laboratories to deploy the TSC as a test bed at NREL’s high-performance computing (HPC) data center in the first half of 2016.

Citi operates and maintains Data Center space in (3) floors 6, 7 and 8 at the 390 Greenwich street facility. This paper focuses on the 7^th and 8^th floors. The 8^th floor data center comprises approximately 15,000 sq ft (1,500m²) with a power consumption of 500kW, and the 7^th floor data center approximately 41,000 sq ft and a power consumption of 1,980kW. The major consumers of energy are the IT equipment, Electrical distribution gear and Cooling equipment. This paper details a study to evaluate the existing conditions of these spaces, and proposals to change to the IT layout, and cooling configuration.

This paper presents data from theoretical modeling and actual laboratory measurements of the UVC intensities at the surface of typical HVAC coils. To understand how effectively the UVC penetrated the coil’s interstitial spaces, measurements were taken at the coil’s surface, 1”, 2”, 3” and 4” depths respectively. UVC intensities were measured and recorded with a calibrated radiometer. The radiometer was capable of producing results that are traceable to NIST and through NIST to the International System of Units. Modelings demonstrating expected reduction of typical coil biofilms are presented using varying UVC intensities at the varying coil depths.

Air is the main carrier of heat, moisture, and other contaminants including the airborne pathogens in the hospital operating rooms. Airflow patterns within the operating rooms and especially in the sterile zone determine the levels of air speeds, temperature, and contaminant concentrations. The spread of pathogens from the sterile zone is directly related to the airflow patterns in the room. This paper with the help of computational fluid dynamics (CFD) analysis demonstrates the effect of return locations and strength of heat sources on the resulting airflow pattern, temperature distribution, and thermal comfort of the occupants within the operating room.

Health care facilities have traditionally used two air changes per hour (ACH) for most spaces. This number can be traced back to the architectural literature of the 1870s. It has been carried forward in codes and standards for nearly 140 years and currently is in ASHRAE Standard 170. This paper proposes an alternative rationale for outdoor air ventilation (fresh air ventilation) in health care spaces, based on the contemporary methodologies of ASHRAE Standard 62.1 and other international indoor air quality standards.

A premature baby is defined as the baby born in the 22th-37th week of the pregnancy. A baby, born before the 28th week of the pregnancy, can live inside of a newborn incubator with a thermoregulation system. Newborn’s death occurs by water and heat loss due to diseases. A decrement in body temperature causes hypothermia and an increment in body temperature causes hyperthermia that result by the death of the neonatal. For the survival of these babies, a suitable and controllable environment has to be provided. In this study, numerical and experimental analyses of a newborn incubator with a laminar flow unit are investigated.

This presentation examines the design of resilient microgrids at hospitals that can support significantly more than the legally mandated emergency circuits and restore the full facility to near normal functionality. The presentation reviews the engineering issues to be considered when retrofitting resilient CHP into an existing facility as well as the environmental water use and overall economics of adding resilience to CHP at critical facilities such as hospitals and data centers.

In 2016, ASHRAE published a whitepaper entitled ‘Data Center Power Equipment Thermal Guidelines and Best Practices’. This whitepaper paper discusses how changes to the data center thermal environment affects power distribution equipment. This session will not only highlight key takeaways from this paper, but extend the discussion to current examples and their associated challenges.

In 2016, ASHRAE Released a brand new Datacom book, entitled ‘IT Equipment Design Impact on Data Center Solutions’. While this book highlights different IT solutions and its supporting networking infrastructure, it does not highlight the prevalence of non-optimal networking solutions and the resulting implications to the data center as a whole. This session not only highlights existing and emerging technologies and their associated best practice considerations, but also focuses on real world solutions and the resulting implications to capacity planning and industry efficiency objectives.

As the electronics industry continues to push the compute performance objectives of Information Technology Equipment by deploying new technologies, there exists the need to match these objectives with power and cooling best practices. This session discusses several new technologies, including non-volatile memory, active optical connectors and graphical processing units and the challenges of deploying these new technologies within server solutions. The session also highlights how these new technologies are approaching the limits of existing rack and room level cooling solutions

One of six speakers in two teams of three presents either for or against.

One of six speakers in two teams of three presents either for or against.

One of six speakers in two teams of three presents either for or against.

One of six speakers in two teams of three presents either for or against.

Data center performance is often focused on energy efficiency. A recent survey found that the only metric for data center cooling performance in common use is PUE. This focus has had significant benefits in reducing energy consumption per kW IT in many modern installations. CFD based studies will show how a singular energy focus may not be the best approach for the business. By ignoring risk to capacity and resilience there is no guarantee of effective cooling. Focusing on effective cooling, on the other hand, is likely to facilitate an energy efficient data center in operation.

A novel method is proposed to reduce the power consumed by data centers cooling infrastructure, blowers and chillers. This method is applied to enclosed aisle configurations in which the CRAH is partially bypassed by inducing hot air into the plenum. This slightly depresses the plenum pressure and eliminates wasteful leakage of cold air. The proposed approach decreases the CRAH blower power and leads to a substantial reduction in the combined power consumption of blowers/fans and chillers.

Non-uniform airflow distribution through perforated tiles can result in inefficient cooling of servers mounted in racks in data centers. The application of strategies to maximize airflow uniformity is therefore very important because of its direct impact on power density capacity. This presentation examines how computer room air handler (CRAH) position and number of operating units as well as perforated tile types affect the airflow uniformity in selected data center applications. Also, the use of mixed tile types to strategically control airflow to accommodate greater rack heat loads is evaluated.

Shipping-container size enclosures now often house modular substations and data centers promising higher quality, lower risk, and better scalability than their stick-built counterparts. The electrical or electronics equipment housed in such enclosures may lack fans or be more like IT equipment of traditional data centers. Often a spatially-detailed thermal analysis is required to ensure that air temperatures are adequately controlled throughout the entire enclosure. Such modular applications introduce several modeling challenges related to the type of equipment housed, the cooling systems employed, and the extreme environments in which they must be designed to operate.

Some researchers have come up with energy-efficient air-conditioning solutions involving the use of desiccants, which largely incorporate the use of low grade waste heat or solar energy rather than electricity. However, issues such as bulkiness of the systems, high initial cost and long pay-back periods, difficulty with retrofitting, non-availability or inconsistent availability of heat sources make such solutions’ market penetration rather challenging. This paper proposes a desiccant (silica gel) coated oblique fin plate-frame structure that can be retrofitted into existing air-ducts. This study suggests the use of oblique fin plate-frame structure to be a plausible alternative to conventional desiccant based air-conditioning solutions.

Zero-equation turbulence models offer improved speed and, potentially, robustness at the expense of solution accuracy relative to the k-ε and other two-equation models typically employed in CFD simulations. For applications – particularly, initial design – in which absolute accuracy is a lower priority, a zero-equation model is appropriate. We assess several zero-equation models for the thermal modeling of large electronics enclosures (e.g., shipping container size). Comparisons are made between the zero-equation models and benchmark 2D and 3D reference scenarios. Researchers recommend a specific zero-equation model for our target applications and discuss its performance relative to the k-ε model.

Chilled beam systems provide sensible cooling in the occupied space using chilled water flowing through modular beams mounted to a ceiling. Such systems achieve greater energy efficiency than all-air system due to larger thermal energy of the chilled water than air, and thus are well-suited for spaces with relatively large sensible cooling load. This paper presents a numerically based study focusing on the performance of combined passive chilled beam (PB) systems. Using computational fluid dynamics (CFD) simulation, the amount of sensible cooling by PB and its impacts on ventilation effectiveness and occupant comfort in a typical office room are investigated.