Concerning construction systems, there are mainly 2 types of water solar photovoltaic systems, namely, piling system and floating system. Compared with the latter, piling solar photovoltaic systems find more difficulties in foundation construction like water pumping, piling driving and fixing brackets, which to some extent result in cost increase.
Merits of Floating Solar Photovoltaics:
1. Saving Land
They are built on water without occupying any land, which can reduce the expense of land acquisition.
2. Boosting Power Generation
Water bodies can cool solar photovoltaic modules whose surface temperature then is prevented from rising, thus power generation increases. According to the comparative analysis conducted by a floating solar PV power plant in Hyogo Prefecture, Japan, owing to the cooling effect of water, the power generation of the panels expects to increase to about 14%.
3. Inhibiting Water Evaporation and Algae Growth
Theoretically, it is feasible to reduce water evaporation, control algae growth and protect water resources by putting solar panels on water.
4. Convenient Operation and Maintenance
Since floating solar photovoltaic power plants are built on water, there is less dust pollution on the modules, which at the same time, can also be easily cleaned. Plus, those photovoltaics are inaccessible for people without fixed duties and animals, which effectively prevents photovoltaic modules from destroying.
5. A Tourist Attraction
Solar photovoltaics being neatly arranged on an endless water surface is a unique view, and it will become a local tourist attraction which can create considerable tourism benefits.
6. Avoiding Shading of Modules
Compared with land, the water is wider, and it successfully avoids shading of modules because there are no shady trees and mountains around. In addition, solar photovoltaic panels can receive light from all directions in a longer time.
7. Reducing the Cost of Installing Tracking Systems
All modules have the same angle and space. It is favorable for the installation and operation of the solar tracking system. Plus, there is no necessity of installing a dual-axis tracking system for each panel, which greatly reduces the cost.
8. Cutting Construction Costs
Solar photovoltaics entail no module elements and brackets, which helps to cut construction costs.
9. Convenient Dispatch of Power
Floating solar photovoltaic power plants are built on the water near cities and villages. It this way, the dispatch of power is convenient as users live nearby. And it helps tackle problems like difficult grid connection and energy rationing and improves dispatch efficiency.
Demerits of Floating Solar Photovoltaics:
1. Strict Requirement for Floating Facilities
Floating facilities should be used for supporting solar photovoltaic panels and meet many strict requirements including low density, long lifetime, favorable bearing capacity and excellent corrosion resistance, frost resistance, thermal resistance, wind resistance and wave resistance.
2. Strict Requirement for Site Selection
Floating solar photovoltaic farms should be located in water areas that feature broad space, stable runoff, low wind speed, favorable light conditions, moderate water level fluctuations, good development conditions, no large-scale shipping and no eco-sensitive zones (ESZs).
3. Many Uncertain Factors
Factors like strong winds, water level fluctuations and frost will negatively impact the plants. And it is necessary to monitor and measure whether photovoltaic modules have an adverse effect on water quality and aquatic life.
4. Difficulties in Construction
When it comes to the construction, it's important to think as many as possible factors. Considering the construction and operation on water, it is difficult to employ heavy machinery to achieve high efficiency and there are more procedures and longer construction time. Many jobs can be done only through diving and shipboard operation, which also takes balance and safety into consideration and cannot damage ponds, dams and other facilities.
Above all, a floating solar power system is a good deal, because it has much more advantages than disadvantages. (Editor: Claire Jeawin)