Applying a novel extra-low temperature dedicated outdoor air system in office buildings for energy efficiency and thermal comfort

The main purpose of this research is to analyze and compare the energy performance of two different novel air conditioning systems; one is a dedicated outdoor air system (DOAS) with a parallel system and the other is a heat-pump-integrated liquid-desiccant and evaporative-cooling-assisted 100% outdoor air system (HPLD-IDECOAS). It was assumed that office buildings served by each system were located in six cities representing four different climatic regions in China. The hourly thermal loads of the office buildings meeting the local building design codes of each selected city were predicted by the TRNSYS 18 software package. The hourly thermal load data were imported into the commercial engineering equation solver (EES) program to estimate the operating energy consumption of each system via detailed energy simulations performed using valid system simulation models. The results show that the HPLD-IDECOAS has higher energy-saving potential than the DOAS with a parallel system in climate regions with high humidity, whereas, in dry regions, the difference in energy consumption between the two systems was not significant.

Download Full-text

Impact of Implementing a Dedicated Outdoor Air System in Parallel with a Multi-Zone Variable-Air Volume System on Energy Consumption, Thermal Comfort, and Life Cycle Cost

10.33915/etd.3915 ◽

2019 ◽

Author(s):

Khaled Alghamdi

Keyword(s):

Life Cycle ◽

Energy Consumption ◽

Thermal Comfort ◽

Life Cycle Cost ◽

Outdoor Air ◽

Variable Air Volume ◽

Air Volume ◽

Air System

Download Full-text

Control Strategies for Daylight and Artificial Lighting in Office Buildings—A Bibliometrically Assisted Review

Energies ◽

10.3390/en14133852 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3852

Author(s):

Daniel Plörer ◽

Sascha Hammes ◽

Martin Hauer ◽

Vincent van Karsbergen ◽

Rainer Pfluger

Keyword(s):

Energy Efficiency ◽

Energy Demand ◽

Control Strategies ◽

Significant Proportion ◽

Decisive Role ◽

Future Trend ◽

Office Buildings ◽

Total Energy Consumption ◽

Integral Control ◽

Artificial Lighting

A significant proportion of the total energy consumption in office buildings is attributable to lighting. Enhancements in energy efficiency are currently achieved through strategies to reduce artificial lighting by intelligent daylight utilization. Control strategies in the field of daylighting and artificial lighting are mostly rule-based and focus either on comfort aspects or energy objectives. This paper aims to provide an overview of published scientific literature on enhanced control strategies, in which new control approaches are critically analysed regarding the fulfilment of energy efficiency targets and comfort criteria simultaneously. For this purpose, subject-specific review articles from the period between 2015 and 2020 and their research sources from as far back as 1978 are analysed. Results show clearly that building controls increasingly need to address multiple trades to achieve a maximum improvement in user comfort and energy efficiency. User acceptance can be highlighted as a decisive factor in achieving targeted system efficiencies, which are highly determined by the ability of active user interaction in the automatic control system. The future trend is moving towards decentralized control concepts including appropriate occupancy detection and space zoning. Simulation-based controls and learning systems are identified as appropriate methods that can play a decisive role in reducing building energy demand through integral control concepts.

Download Full-text

Experimental Data and Simulations of Performance and Thermal Comfort in a Typical Mediterranean House

Energies ◽

10.3390/en14113311 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3311

Author(s):

Víctor Pérez-Andreu ◽

Carolina Aparicio-Fernández ◽

José-Luis Vivancos ◽

Javier Cárcel-Carrasco

Keyword(s):

Energy Efficiency ◽

Thermal Comfort ◽

Energy Demand ◽

Natural Ventilation ◽

Thermal Characterization ◽

Energy Performance ◽

Building Stock ◽

Energy Demands ◽

Dwelling House ◽

Account Standard

The number of buildings renovated following the introduction of European energy-efficiency policy represents a small number of buildings in Spain. So, the main Spanish building stock needs an urgent energy renovation. Using passive strategies is essential, and thermal characterization and predictive tests of the energy-efficiency improvements achieving acceptable levels of comfort for their users are urgently necessary. This study analyzes the energy performance and thermal comfort of the users in a typical Mediterranean dwelling house. A transient simulation has been used to acquire the scope of Spanish standards for its energy rehabilitation, taking into account standard comfort conditions. The work is based on thermal monitoring of the building and a numerical validated model developed in TRNSYS. Energy demands for different models have been calculated considering different passive constructive measures combined with real wind site conditions and the behavior of users related to natural ventilation. This methodology has given us the necessary information to decide the best solution in relation to energy demand and facility of implementation. The thermal comfort for different models is not directly related to energy demand and has allowed checking when and where the measures need to be done.

Download Full-text