A Framework for Facilitating Low-Income Net-Zero Energy Housing Delivery in Developing Countries: Insights from a Practical Case in South Africa

Abstract

• LI-NZEH has potential to address South Africa's housing and energy crises sustainably. • A 97% CO 2 reduction and 82% cost reduction in LI-NZEH versus conventional housing was demonstrated. • LI-NZEH remains less sensitive to price fluctuations, ensuring long-term economic viability. • Collaboration needed to promote and invest in LI-NZEH production and R&D. Providing sustainable and affordable housing for low-income populations is challenging, exacerbated by housing backlogs, energy crises, and the need for carbon-neutral transitions. While innovative building technologies (IBTs) and Net-Zero Energy (NZE) solutions have been proposed, their adoption in South Africa's low-cost housing is limited due to the lack of a coherent framework. This study fills this gap by developing a framework using ISO14040, EN 15978, and RICS whole life carbon assessment (WLCA) principles for delivering optimal sustainability and affordability in IBT-enabled LI-NZEHs. An assessment of South Africa's first IBT-enabled LI-NZEH prototype showed a 97% reduction in CO2 emissions and an 82% reduction in life cycle costs compared to a conventional low-income house, due to IBTs, lower operational costs, and zero energy operation. Additionally, sensitivity analysis results indicate that LI-NZEH is less sensitive to price fluctuations, further reinforcing its long-term economic viability. These results led to the creation of a framework for delivering IBT-enabled LI-NZEHs in South Africa, aiming to address energy crises, improve low-income households' quality of life, and reduce centralized energy demand. The affordability and sustainability benefits, along with job creation and reduced transportation emissions through local manufacturing, present a compelling case for their adoption. This study offers valuable insights for policymakers, developers, and researchers tackling housing and energy challenges in South Africa and similar contexts.