This paper aims to review the state of the art technologies for the energy efficiency within the hospitals sector. Hospitals are liable for an unstable amount of energy demand and joint emissions, because of their 24/7 nature of operation and hence resulting larger energy consumption than a typical commercial building. Additionally, they need high quality and warranted supplies of electricity. Due to increased energy demand and therefore the depletion of existing fossil fuel based sources, it is required to use the energy more efficient.

Green building is an important measure to deal with energy and environment problems in the construction sector of the world. In this study, knowledge mapping analysis is used, and 3,060 articles are selected for further study (1900–2019). Based on CiteSpace (5.3.R4 SE 64-bit), the knowledge base, hot topics and research trends of green-building-related research are presented. The key highlights of the overall analysis results are: (1) Research on green buildings has received more extensive attention in the 21st century.

On an average, India has more than 3000 Cooling Degree Days (CDD). The multifamily public housing being constructed under India’s Prime Minister Awas Yojana (PMAY) is aimed at providing formal housing to the society’s Economic Weaker Section (EWS). It is essential that this housing delivers thermally comfortable in-doors to the occupants. This study mapped the design and construction practices followed under PMAY Urban (PMAY-U) against India’s Residential Energy Building Code, Eco Niwas Samhita (ENS). The metric prescribed in ENS is Residential Envelope Transmittance Value (RETV).