Preliminary Performance Tests and Simulation of a V-Shape Roof Guide Vane Mounted on an Eco-Roof System

Abstract

The technical and economic features of a patented V-shape roof guide vane (VRGV) with a solar and wind power generation system mounted on an eco-roof system are presented in this paper. Moreover, this innovative VRGV was investigated on for the purpose of improving the performance of a vertical axis wind turbine (VAWT), which was installed on an eco-roof system to solve the low-efficiency power generation problem of the wind turbines under the condition of a low wind speed. This paper proposes a preliminary study for the performance of the VAWT with the VRGV on a building. This research used a mock-up building with a double slope roof, where a five straight-bladed VAWT was mounted and tested under two conditions, with and without the VRGV. From the comparative experiments, the self-starting performance and rotational speed of the VAWT mounted above a double slope roof with the VRGV have been significantly improved compared to the VAWT without the VRGV. Further, the power coefficient (Cp) of the VAWT can be augmented to about 71.2% increment due to the VRGV design. In addition, numerical simulations by computational fluid dynamics (CFD) were proposed to verify the augmented effect of the Cp of the VAWT under the influence of the VRGV in the experiment. Besides, economic estimation of the VRGV was conducted.

Preliminary Techno–Environment–Economic Evaluation of an Innovative Hybrid Renewable Energy Harvester System for Residential Application

“…This technical viability study shows that a wind velocity percentage increment of 63% can be obtained in the presence of the VRGV with an inclination angle of 19.5 • via CFD simulations and experiments. The VRGV design can enhance the self-starting behavior of the VAWT mounted on the double-sloped roof by 13.78% more than that of the case without the VRGV [30]. Higher power coefficient values can be achieved by the VAWT mounted in this hybrid renewable energy harvester system with the VRGV, than that of the case without the VRGV.…”

“…There are many economic-environmental performance indicators used in the field of product evaluation, such as LCC [27,[30][31][32], LCA (life-cycle assessment) [33][34][35], LCOE (levelized cost of energy) [36,37], NPV (net present value) [31], EPBT (energy payback time) [38], ROI (return on investment) [39], BCR (benefit-to-cost ratio) [40], IRR (internal rate of return) [39], UEC (unit energy cost), and PBP (payback period) [31,39,41].…”

“…The parameters of the VAWTs are shown in Table 2. The rotational and power performance of the VAWTs installed in this hybrid renewable energy harvester was optimized by the increased wind speed caused by the VRGV [30]. The most visible feature of the system is a V-shaped roof guide vane (VRGV), installed on top of the building, which helps in concentrating the airflow from a large area and increasing the wind speed into the wind turbine.…”

“…The parameters of the VAWTs are shown in Table 2. The rotational and power performance of the VAWTs installed in this hybrid renewable energy harvester was optimized by the increased wind speed caused by the VRGV [30]. Solar panels can be strategically placed on top of the pitched roof and the VRGV, as shown in Figure 3.…”

Vertical Axis Wind Turbine Adapted For Installation on Pitched Roof with Photovoltaic Panels and Effects on Heat Transfer

“…This is however for a single wind-direction, it is expected that different wind directions will negatively impact the turbine efficiency (due to reduced relative wind speed since the wind angle would not be perpendicular to SWT axis). Addition of a V-shaped roof guide as in [1], leads to local wind speed increase which significantly increases the SWT efficiency (up to 70% which was also the case in [1]). The turbulence generated by the turbine wake also increases the heat conduction of the PV system, which can act as a passive cooling mechanism.…”