Journal: Energies, Volume 16, Issue 19
Authors: Sriraj Gokarakonda, Christoph Van Treeck, Rajan Rawal, Stefan Thomas
Abstract: Studies show that people can tolerate elevated temperatures in the presence of appreciable air movement (e.g., from using ceiling
Keywords: room air-conditioners; ceiling fans; set-point temperature; thermal comfort; user behaviour; sensors and monitoring
Journal: Energy and Built Environment, Volume 4, Issue 6
Authors: Sriraj Gokarakonda, Christoph Van Treeck, Rajan Rawal, Stefan Thomas
Abstract: Studies show that people can tolerate elevated temperatures in the presence of appreciable air movement (e.g., by using ceiling fans). This results space cooling
Keywords: Room air-conditioners; Ceiling fans; Set point temperature; Thermal comfort
Journal: Journal of Building Performance Simulation, Volume 15, Issue 6
Authors: Saranya Anbarasu, Wangada Zuo, Yangyang Fu, Yash Shukla, Rajan Rawal
Abstract:
Keywords: direct evaporative cooler, modelica, physical-based model
Journal: Building and Environment. Volume 219
Authors: Rajan Rawal, Yash Shukla, Vishnu Vardhan, Sneha Asrani, Marcel Schweiker, Richard de Dear, Vishal Garg, Jyotirmay Mathur, Sanjay Prakash, Saurabh Diddi, Vikash Ranjan, Abdullah N.
Abstract: Indian residences are vulnerable to heat-driven discomfort amid the mounting prevalence of weather extremes, residential design and construction practices, and densifying urbanscapes. Therefore, it is vital to understand the thermal comfort characteristics of nationwide residences. This study proposes an adaptive thermal comfort model based on yearlong field surveys in eight cities located across five climate zones of India – the India Model for Adaptive Comfort - Residential (IMAC-R). The model prescribes the operative temperature bands for 80% and 90% thermal acceptability in correlation with the outdoor reference temperature, applicable to mixed-mode (MM) and naturally ventilated (NV) residences.
More than 80% of the Indian residential occupants experienced a neutral thermal sensation in the indoor operative range of 16.3–35 °C in response to a 5.5–33 °C variation in the 30-day outdoor running mean temperature. Comparing the proposed model with the PMV model revealed that the latter underpredicts the thermal adaptivity of Indian occupants. The model was also compared against its predecessor – India Model for Adaptive Comfort for Commercial Buildings (IMAC MM and NV), along with relevant global and regional thermal comfort models. On average, the neutral temperature prescribed by IMAC-R was warmer than the temperatures prescribed by IMAC MM and NV by 2.9 °C and 2.1 °C, respectively; it was also warmer than the temperature prescribed by the recent ASHRAE-55 and EN 16798-1 models by 2 °C and 0.3 °C, respectively. IMAC-R reserves the prospect of addressing the thermal comfort needs of the national population while paving the way for long-term energy savings and climate action.
Keywords: Thermal adaptation; Adaptive comfort model; Indian residences; Mixed-mode ventilation; Natural ventilation; IMAC
Journal: Buildings and Cities, Volume 3, Issue 1
Authors: Brian Ford, Dejan Mumovic, Rajan Rawal
Abstract: Far from being a panacea, air-conditioning is shown to create social, environmental and economic problems. Alternatives to air-conditioning are identified as
Keywords: Adaptation air-conditioning, climate change, cooling, design, energy demand,, environmental control, passive cooling, public policy, thermal comfort
Journal: Buildings & Cities, Volume 3, Issue 1
Authors: Mili Jain, Rajan Rawal
Abstract: This study quantifies the gap between net-zero energy and net-zero carbon through a life cycle assessment (LCA) of a net-zero energy building (NZEB) in Ahmedabad,
Keywords: Buildings; carbon footprint;embodied carbon; life cycleassessment; net-zero carbon;net-zero energy; India
Journal: Buildings and Cities, Volume 3, Issue 1
Authors: Malcolm Cook, Yash Shukla, Rajan Rawal, Charalampos Angelopoulos, Luciano Caruggi-De-Faria, Dennis Loveday, Eftychia Spentzou, Jayamin Patel
Abstract: Rapidly developing economies of countries in hot climates
Keywords: control cooling, dwellings, energy, mixed mode, residential, thermal comfort, ventilation, India
Journal: Building and Environment, Volume 217
Authors: Rashmin Damle, Nikita Khatri, Rajan Rawal
Abstract: Traditional buildings since many centuries have used lime as a binder and finishing material. However, in contemporary construction practices, lime mortar and lime
Journal: Energies, Volume 15, Issue 6
Authors: Sriraj Gokarakonda, Christoph van Treeck, Rajan Rawal
Keywords: elevated air speed; thermal comfort; mixed-mode buildings; set point temperature; energy consumption in buildings
Journal: The Journal of Engineering Research (TJER), Volume 18, Issue 2
Authors: Sneha Asrani, Rajan Rawal, Yash Shukla, Peter Graham, Priyanka Bhanushali, Arjun Desai
Abstract: On an average, India has more than 3000 Cooling Degree Days (CDD).
Journal: Science and Technology for the Built Environment
Authors: Anmol Mathur, Pamela Fennell, Rajan Rawal, Ivan Korolija
: Urban building energy models (UBEM) are driving sustainable design and operations of cities by combining urban datasets with energy simulations. UBEMs are developed from a range of inputs on the spatial and semantic details of the buildings, and the systems affecting their energy performance. Large geographical scales with finer spatio-temporal details increase the challenges of data processing for a reliable UBEM. Thus, it is essential to understand the impact of increasing the resolution of model inputs on the outputs to balance the efforts spent on model development, filling data gaps and maintaining the reliability of the results. This research introduces a Fit-for-Purpose modelling strategy and extends the concept of Levels of Detail (LoD) used for 3D models, to UBEM characteristics including occupancy, geometry, context, modelling methodology, and calibration with the proposed model characterisation framework. A case study based on a 0.3km2 area of Ahmedabad, India, is presented to demonstrate the framework. The results highlight a need for a higher LoD in occupancy modelling for the residential and educational buildings, whereas a higher LoD is more important for the commercial buildings’ envelope characteristics. These insights will enable a highly targeted supplementary data collection approach for the UBEM of the entire city.
Journal: Building and Cities, Volume 2, Issue 1
Authors: Nidhi Rai Jain, Rajan Rawal, Vishnu Vardhan, Shubhashis Dey
Abstract: India’s current standards and labels for room air-conditioners (RACs) account for energy efficiency, but omit other important criteria that could influence product development and
Journal: Building and Environment, Volume 123