Trial / Demo
Congratulations to Allen Mei, Simulation Team Technical Leader from Cyclone Energy Group in America, who won the America VE User of the Year.
Allen’s submission stood out for his extensive portfolio of work submitted, including a range of high-quality simulation projects for low-rise, mid-rise and high-rise building types. His wide range of simulation included internal and external CFD Airflow simulation, loads and HVAC optimisation, energy and carbon modelling and LEED energy modelling.
The TIGER Central plant project for Princeton University could have been a standalone winner. Allen’s use of the “scheduled loads” feature in ApacheHVAC demonstrated an expertise to isolate appropriate demands that would help to evaluate the all-electric HVAC system in a time-efficient manner.
Princeton University TIGER Central Plant Sequencing and Optimisation
Princeton University is constructing a state-of-the-art, all-electric central plant that features geo-coupled heat pump chillers and thermal energy storage systems (TES). The plant is designed to provide simultaneous cooling and heating capabilities. Additionally, the University is upgrading its existing West Plant, which houses electric chillers, steam turbine chillers and TES. The new plant will be seamlessly integrated with the existing facility, delivering chilled water and hot water for the entire campus. The institution also has a combined heat and power system.
IESVE was exclusively used for all four simulations and analytics of this project, showing its holistic and diverse capabilities in building simulations. The powerful tool also shows incredible reliability and accuracy for simulating various complex systems.
Photo Credit: ZGF www.zgf.com
Simulation 1 - TIGER Central Plant Chiller Room Internal CFD
The first study was an internal CFD simulation for the new TIGER Plant chiller room. Given that the chillers and pumps release a substantial amount of heat into the space, implementing an effective heat mitigation strategy is crucial for the optimal operation of the plant. Apache was used to set up boundary conditions and subsequently transitioned to MicroFlo-CFD for simulating internal air flow and temperature distributions. The study focused on evaluating various louver and exhaust fan designs, providing valuable insights to the mechanical engineer to determine the most effective option. The chosen option, informed by the simulation results, was then incorporated into the final design, ensuring that the plant's operational efficiency and heat management were optimised.
Photo Credit: Salas O'Brien salasobrien.com
Simulation 2 - TIGER Central Plant Sound Wall External CFD
The second study was an external CFD simulation for sound wall placements at the new TIGER plant. The primary objective of these sound walls was to mitigate noise levels in the surrounding area. Recognising the potential impact on the effectiveness of air intakes from the louvers, Microflo-CFD was employed to investigate the optimal distance and location for these sound walls, analysing air flow and turbulence patterns. The recommended placement derived from the study was reflected in the final design.
Simulation 3 - TIGER and West Plant Operational Sequencing and Efficiency Study
The third study was to simulate the operational sequencing and efficiency when the new TIGER plant connects to the existing West Plant. Working closely with the mechanical engineer, campus building loads were imported into IESVE via its Python Free Form Data(FDD) function. The data was later used in ApacheHVAC as “scheduled load” so the central plant equipment can run against it. The heat pump chillers, electric centrifugal chillers, steam turbine chillers, TES, geo-exchange and heat recovery loop were built in ApacheHVAC and different staging schemes were run to find the optimised setup. The efficiency data was swiftly extracted using the powerful VistaPro. Loads against power input profiles were also easily visualised. The University's onsite PV was also simulated directly in IESVE, contributing to further investigations into load shaving and sequencing controls.
The study revealed that when the TIGER Plant came online, cooling efficiency would improve by 34%, and heating could be made entirely electric, resulting in a remarkable 609% increase in efficiency. With the new configuration, Princeton aims to reduce carbon emissions by 40% compared to FY 2021, with a projected 66% reduction when the PV system comes online.
Simulation 4 - TIGER Plant LEED Energy Modelling
The fourth study focused on obtaining LEED Certification for the TIGER Plant. IESVE was used to create a LEED Energy Model for the plant building. Collaborating closely with design teams, various factors were analysed such as envelope options, AHU controls and lighting power densities, ensuring the project met LEED targets. The project is demonstrating a significant achievement with 57% energy and cost savings over the LEED v4 Baseline, positioning it to earn all 18 Optimize Energy Performance Points.
Note: For a central plant building, the energy consumption utilised to generate thermal energy (i.e., chilled water or hot water) for use in buildings outside the LEED Project Boundary does not need to be considered within the energy models for Minimum Energy Performance. However, any heat gains from the central plant equipment, and the impact of these loads on the local heating and cooling systems of the central plant, must be accounted for within the model.
Acknowledgements for their significant contributions of this project to:
Energy Masterplanning: Burns & McDonnell
Plant Design: Salas O'Brien
Princeton University Energy Plant Team
