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Energy efficient building design and decarbonization have become a high priority in the quest to reduce the effects of pollution, conserve natural resources and slow climate change. Many engineers and stakeholders want to reduce energy consumption and related carbon emissions from buildings but may not know how to do so. This article analyzes existing net […]

“Technically tight” means a refrigeration or AC system can leak a tiny, controlled amount of refrigerant—low enough that it won’t hurt efficiency, safety, or the environment. Regulations for F‑gases aim at ≤ 5 g/year, but the real acceptable rate depends on charge size, refrigerant hazard, and maintenance interval. Good design, quality construction, and regular checks create durably […]

The article analyzes CO₂ buildup inside car cabins when using air recirculation mode, which affects driver alertness and health. It recommends using CO₂ sensors and applying ASHRAE Standard 62-2001 to automatically control fresh air intake. Tests and simulations show that maintaining a minimum of 40% fresh air (Partial Recirculation Factor) keeps CO₂ levels below 1,100 […]

Chilled water cooling systems consume nearly 50% of building energy required to meet cooling loads, especially in hot, humid climates.1 Chiller COP can be improved with the optimal chilled water supply temperature, and significant amounts of system energy can be reduced. Similarly, chilled water distribution pumps designed with high temperature delta T will have less […]

This study validates a Temperature Controlled Airflow (TcAF) system that uses cooler air over sterile zones and warmer air at the periphery to reduce contamination. Tested in mock and real surgeries, TcAF maintained microbial levels below 10 CFU/m³, achieving ultraclean air standards and enhancing surgical infection control.

This study critically examines the role of heat pumps in decarbonization strategies, particularly in regions characterized by high CO2 emissions from electricity generation. It highlights the performance disparities between air-source heat pumps (ASHPs) and ground-source heat pumps (GSHPs) in cold climates, where the environmental benefits may be undermined due to higher emissions. The paper delves […]