Rooftop PV and the Renewable Energy Transition; a Review of Driving Forces and Analytical Frameworks

Sustainable construction through energy management practices: an integrated hierarchal framework of drivers in the construction sector

Reducing energy usage and promoting energy management practices remain hot issues in the construction sector. Construction firms are not interested to adopt energy conservation and management practices in their projects. Despite the successful integration of energy management practices in developed nations, their adaptability in developing countries, especially in Pakistan, is at a slow pace. Therefore, drivers to energy management practices need to be realized for its adoption. Based on this, the current study intends to evaluate the drivers of energy management practices adopted in the construction sector of Pakistan by using a four-stage methodology. Fuzzy Delphi method (FDM), interpretive structural modeling (ISM), and Matrice d'Impacts Croises Multiplication Appliques a un Classement (MICMAC) analysis were integrated with prioritizing essential drivers. Increased tax imposition on construction companies for energy usage and pollution contribution, promotion of investment subsidies for energy efficiency technologies, and increased enforcement of government rules and regulations regarding on-site energy management practices arose as significant drivers to adoption of energy management practices in the construction sector of Pakistan. These results will be helpful for policymakers to develop effective policies for integrating energy management practices in the construction sector. This study contributes significantly by developing a novel model of drivers affecting EMP adoption in the Pakistani construction sector. Further research might be expanded to other developing countries to validate current results.

Assessment of Waterfront Office Redevelopment Plan on Optimal Building Arrangements with Rooftop Photovoltaics: A Case Study for Shinagawa, Tokyo

Designing waterfront redevelopment generally focuses on attractiveness, leisure, and beauty, resulting in various types of building and block shapes with limited considerations on environmental aspects. However, increasing climate change impacts necessitate these buildings to be sustainable, resilient, and zero CO2 emissions. By producing five scenarios (plus existing buildings) with constant floor areas, we investigated how buildings and district forms with building integrated photovoltaics (BIPV) affect energy consumption and production, self-sufficiency, CO2 emission, and energy costs in the context of waterfront redevelopment in Tokyo. From estimated hourly electricity demands of the buildings, techno-economic analyses were conducted for rooftop PV systems for 2018 and 2030 with declining costs of rooftop PV systems. We found that environmental building designs with rooftop PV system are increasingly economical in Tokyo with CO2 emission reduction of 2–9% that depends on rooftop sizes. Payback periods drop from 14 years in 2018 to 6 years in 2030. Toward net-zero CO2 emissions by 2050, immediate actions are necessary to install rooftop PVs on existing and new buildings with energy efficiency improvements by construction industry and building owners. To facilitate such actions, national and local governments need to adopt appropriate policies.

Study on Performance of Rooftop Solar Power Generation Combined with Battery Storage at Office Building in Northeast Region, Vietnam

At present, renewable energy sources are considered to ensure energy security and combat climate change. Vietnam has a high potential for solar power development, especially in the central region and the southern region. However, the northeast region has the lowest solar radiation value, so it can cause difficulty for rooftop solar power investment. In this paper, the study results analyze the financial efficiency of the grid-tied rooftop solar power system with battery storage and compared it to the grid-tied rooftop solar power system without battery storage. The experimental data of a grid-tied solar power system with battery storage at an office building in the northeast region of Vietnam is collected to evaluate the system’s operation performance in real conditions. The study results present that the financial efficiency of rooftop grid-tied power project with and without storage is viable since the benefit-cost ratio (B–C) is larger than one, and internal rate of return (IRR) and net present value (NPV) are positive. However, the grid-tied rooftop solar power system with storage is not quite feasible in case of changing the electricity selling price and investment cost even though the grid-tied solar power system using the storage device can operate more flexibly. The payback period of the grid-tied solar power system with storage is 6.2 years longer and the total profit is nearly 1.9 times lower than the solar power system without battery storage due to the difference in the price of the inverters and the battery. In contrast, the grid-tied solar power system without battery storage shows better financial efficiency but strongly depends on the operation of the utility grid.