Techno-economic analysis of a wind–solar hybrid renewable energy system with rainwater collection feature for urban high-rise application

The technical and economic feasibility study of an innovative wind–solar hybrid renewable energy generation system with rainwater collection feature for electrical energy generation is presented in this paper. The power generated would supply part of the energy requirements of the high-rise building where the system is installed. The system integrates and optimizes several green technologies; including urban wind turbine, solar cell module and rain water collector. The design was conceptualized based on the experiences acquired during the development and testing of a suitable wind turbine for Malaysian applications. It is compact and can be built on top of high-rise buildings in order to provide on-site renewable power to the building. It overcomes the inferior aspect on the low wind speed by channeling and increasing the speed of the high altitude free-stream wind through the power-augmentation-guide-vane (PAGV) before it enters the wind turbine at the center portion. The shape or appearance of the PAGV that surrounds the wind turbine can be blended into the building architecture without negative visual impact (becomes part of the building). The design improves the starting behavior of wind turbines. It is also safer to people around and reduces noise pollution. The techno-economic analysis is carried out by applying the life cycle cost (LCC) method. The LCC method takes into consideration the complete range of costs and makes cash flows time-equivalent. The evaluations show that for a system with the PAGV (30 m diameter and 14 m high) and an H-rotor vertical axis wind turbine (17 m diameter and 9 m high) mounted on the top of a 220 m high building, the estimated annual energy savings is 195.2 MW h/year.

This wind–solar hybrid renewable energy system is a new concept of the utilization, integration and optimization of existing renewable energy and rain water harvesting technologies. It is compact and can be built on the top of high rise buildings to provide on-site green power to that building or feed into the grid line. This system utilizes the advantages of Malaysian climate, i.e. high solar radiation and rainfall for green energy generation and free water supply. It also overcomes the inferior aspect on the low wind speed by guiding and increasing the speed of the high altitude free-stream wind from all directions radially through power-augmentation-guide-vane (PAGV) before entering the wind turbine at center portion. The PAGV is an innovative design used to guide and create venturi effect to increase the wind speed before the wind-stream enters wind turbine. The system must also be designed to provide optimum surface area for solar panel (solar thermal or photovoltaic or solar PV/T)) installation and battery compartment for power storage. In addition; rain water collection feature must be built-into the system design. The system is recommended to be sited on the top of high rise buildings or structures with its appearance or outer design can be blended into the building architecture without negative visual impact. With this system, the size of wind turbine can be reduced for a given power output and the noise is also reduced since it is contained in the PAGV. The design is also safer and suitable to be used in populated area. Mesh can be mounted at the entrance of the PAGV to prevent the bird-strike. This system can eliminate or minimize the current problems concerning public acceptance of wind energy, i.e. poor starting behavior in low wind speed, noise, visual impact, electromagnetic interference, safety and environmental factors.Figure optionsDownload as PowerPoint slideHighlights
► This wind, solar and rain harvester integrates existing renewable energy and rain water harvesting technologies.
► The system overcomes the inferior aspect on the low wind speed by introducing the power-augmentation-guide-vane (PAGV).
► The PAGV is used to guide and create venturi effect to increase the wind speed before the wind-stream enters wind turbine.
► This design can be blended into the building architecture without negative visual impact, and is safer for populated area.
► The PAGV improves the wind turbine’s starting behavior and prolongs its operating hour, thus reduces the payback period.