Impact of Green Building Design on Energy Efficiency

Abstract

The building sector is a major consumer of energy and an important source of greenhouse gas emissions. Green building design seeks to reduce energy demand while maintaining thermal comfort, indoor environmental quality, and functional performance. This paper examines the impact of green building design on energy efficiency, focusing on passive design, building envelopes, daylighting, natural ventilation, heating and cooling systems, lighting, renewable energy, smart controls, and building performance evaluation. Evidence from systematic reviews indicates that energy efficiency in sustainable buildings depends on an integrated combination of architectural design, efficient technologies, renewable energy, and effective operation. Greenery systems can reduce solar radiation and heat transfer through building envelopes in suitable climates, while building energy-efficiency strategies can lower energy demand through improved envelopes, efficient equipment, and control systems. The paper argues that the greatest benefits are achieved when energy performance is addressed from the earliest design stage rather than through isolated technological additions. At the same time, actual performance can differ from predicted performance because of occupant behaviour, maintenance, commissioning, and operational practices. Green building design should therefore be understood as a whole-building strategy supported by simulation, monitoring, post-occupancy evaluation, and appropriate energy-performance standards.