There are different types of arrays of floating solar photovoltaic projects such as arrays with brackets and inclined arrays of floating bodies. Arrays with brackets can be installed at the optimal angle of inclination, but they entail a large number of brackets and floating bodies and the foundation have to bear intensified stress. On the contrary, the stress exerted on the foundation of inclined arrays is small and there is a small amount of steel used. Although they are easy to maintain, they cannot be installed at the optimal angle of inclination, which means that part of generated power is sacrificed. Now take inclined arrays as an example, we will focus on cost and revenue analysis of floating solar photovoltaic.
1. Power Generation
In terms of power generation, compared with ground PV, floating PV may generate more electricity, as affected by temperature and reflectivity. In the actual calculation process of power generation, we also take into account various factors that may impact power generation, such as temperature, system availability, power losses in photovoltaic arrays, DC transmission line losses, lower efficiency caused by electrical equipment, energy loss in PV plants. Specifically, it is estimated that temperature affects power generation by about 3-4%, then the influence of the surface temperature of floating PV is likely to 1-2%. Concerning the influence of reflectivity, under the same conditions like location, angle of inclination, it is estimated that power produced by floating photovoltaics is about 3-5% higher than that of ground photovoltaics. However, according to a comparison of results from domestic and overseas surveys on floating PV and ground PV, power generation of floating solar panels can increase by 10-15%, compared with the panels installed at the same angle on rooftops and on land. Because the actual collected data is relatively inadequate, it is necessary to conduct cost and revenue analysis.
2. Cost Vs. Revenue Analysis
Considering the changes in investment and factors that influence power generation in the above analysis, through estimation under the same conditions with ground PV, floating PV has the internal rate of return (IRR) of all investment decreased by about 13% and the IRR of capital by 24%, when calculated according to the calculating data of power generation (i.e., when power generation of floating PV is 3% to 5% higher than ground PV). In contrast, floating PV has the IRR of all investment increased by about 7% and the IRR of capital by 13%, when calculated according to actual comparative data obtained from foreign surveys (i.e., when power generation of floating PV is 10% to 15% higher than ground PV).
At this stage, many countries flip the switch on floating photovoltaic power plants, but they are somewhat fettered due in part to the costs, land scarcity, environmental concerns and other reasons. As China vigorously promotes the development of solar photovoltaic technologies, it is believed that large-scale application of floating PV is just around the corner. Domestic PV developers should carry out comparative experiments and analysis on actual power generation of floating PV and ground PV under the same conditions, so that they have a grasp of more accurate basis of decision making for the development of subsequent projects. (Editor: Claire Jeawin)