“Site maintenance will be the most essential core to the development of the solar industry in the future”, commented Hsu Sheng-feng, Manager of the Energy Division at major Taiwanese solar inverter manufacturer Ablerex. The lifespan for a solar power plant is usually more than 20 years, and the development focuses in solar power in the future lie on the maintenance of the efficiency in power generation for the next few years, as well as the simultaneous reduction in the detection time and cost for solar panels.
Taiwan has been vigorously implementing an energy transformation in recent years, with solar power as priority, where the government plans to install 6.5GW of solar power in 2020, before eventually achieving the capacity target of 20GW in 2025. The enormous vision has attracted numerous foreign companies to station and develop in Taiwan, and there has been an increased number of completed large power plants.
The real challenge begins after the installations and grid construction of solar panels. The average lifespan of solar panels are approximately 20-25 years, and may be extended to 30 years through technology advancement. A power plant has to operate for at least more than 20 years, and solar panels will eventually experience issues of dust, bird droppings, and dirt over time, where the shadow and shade on top of the solar panels caused by the northeastern monsoon will also impact the power generation of solar panels, and leads to incompatibility for solar cells, which further reduces the overall solar performance and damages the profit of the proprietors at the end.
Hence, the less the shadow the better for solar power plants, which requires the care and maintenance of professionals in order to maintain the peak efficiency of solar power generation and avoid revenue negligence. The current maintenance method primarily consists of drones and infrared detection, where the infrared thermal imaging instrument from the drone inspects for abnormal temperature from the solar panels, then predicts issues such as hot spot defect and shorted diodes on the solar panels through the abnormal temperature status.
However, Hsu Sheng-feng pointed out that drones require on-spot mounting and operation, as well as a license for operation in accordance with the existing regulations in Taiwan, which induces substantial cost in time and manpower, where a regular inspection will be impossible due to the elevated expenses, thus the current solar power plants lack an effective yet cost efficient maintenance tool.
Due to this concern, Ablerex has altered the public’s imagination on solar inverters while releasing the brand new detection solution. A solar inverter is primarily used to convert the direct current emitted from solar panels into alternating current that can be used by the power grid, and Ablerex has enhanced the values of inverters by concatenating the I-V curve efficiency detection function with the solar panels, paired with a smart cloud management platform of solar photovoltaic, in order to easily detect for abnormalities regarding performance, circuit, and relevant endpoints of the solar panel concatenation, which achieves an online maintenance.
The so-called I-V curve draws out a correlation between the electric current and voltage of the solar panel concatenation through electronic instruments. As commented by Hsu Sheng-feng, an I-V curve resembles the lifeline of solar panels, and is able to indicate the issues of the site through the “symptoms”, without needing on-site technical staffs.
Take Ablerex’s 468kW solar rooftop from the chicken coop at Fangyuan of Changhua as an example, staffs discovered an anomaly of “deepening of horizontal slope”, which was thought to be the accumulation of sand and dust. After inspecting the site using a drone, a cone sand dam was discovered underneath the solar panels resulted from northeastern monsoon and the close proximity to the coast, and the I-V curve rapidly returned to normal after the dam was removed. Under Ablerex’s estimation, the sand damn had caused 13.8% loss of power generation, and a TWD$8.14 million loss would be the result for the 468kW power plant in the next 20 years if it was ignored.
I-V curve for the dust accumulated sand dam.
Ablerex had obtained the patent in 2017, and became the first company in Taiwan to receive the VPC certification in 2019, which implements I-V curve detection through inverters without the need of additional I-V curve scanning instruments and inspection software, where technical staffs are able to conduct an inspection that lasts around 10 seconds on remote control without executing routine patrols, and discover risks that would impact the power generation and cause fire, including shades, dust, abnormal hot spots, and shorted bypass diodes. Hsu Sheng-feng predicts that the approach will eliminate more than 80% of inspection cost, as well as elevate efficiency, power generation forecast, and forecast precision, which will help with TPC in dispatching power.
VPC certificate for Ablerex’s inverter/patent certificate
Ablerex will also march towards intellectualization in the future. The current I-V curve inspection is monitored and interpreted manually, which requires more time when adopting on GW level large power plants, where the accompaniment with a smart system will be able to integrate various information and data analysis, and allows the system to implement autonomous determination through machine learning. Furthermore, the inspection range will also extend to the direct current end to seek for potential safety hazards and further elevate the security and fire prevention mechanism of power plants.
Ablerex will focus on technology as the core element in the future and continue to plough in the field of solar inverters. As the market scale of solar establishment gradually increases, Taiwan has become a contested location for inverters, and Ablerex has implemented a comprehensive arrangement in accordance with market differentiation and segmentation, where the shipment volume during the first quarter of 2020 had achieved a YoY growth of 30%. Hsu Sheng-feng believes that the COVID-19 pandemic will not affect the demand for solar power in Taiwan, and the industry will regain its vitality as the pandemic alleviates, despite the short term reduction in dynamics.
(Photo source: Ablerex)
