Polaris solar PV net news: with the policies of the Chinese Government to promote photovoltaic applications have been issued, the curtain of PV development in China was opened.
However, a photovoltaic power station built at the same time, the component’s quality problems are emerging. Third-party testing organization Beijing Jian Heng Ji Zhenshuang Certification Center Deputy Director told a seminar in August, “in the country’s 32 provinces, volume 3.3GW, 425, including large power plants and distributed PV power station’s equipment detected, PV modules there are hot spots, cracked, attenuation, etc.”
PV quality storage worries
Photovoltaic is a relatively mature technology, with a predictable source of energy output and a stable cash flow, are some of the country’s power generation group known as the cash cow of basking in the Sun. Abroad, PV power station after the securitization is a very sophisticated financial products, many funds hold.
Reached 25-year life cycle of photovoltaic plant, component quality is one of the decisive factors that affect investment returns. If the component life is substandard or conversion decay too quickly, then all the investment measure is building castles in the sand.
Domestic solar power station has been completed, it can be the potential takeover target very small margin of safety, in addition to the uncertainty of the policy and market environment factors, greatest fear, it is the quality of these PV lack the confidence.
On August 5, Wang Sicheng, a researcher at the Energy Research Institute of NDRC on large-scale PV power plant in Hohhot in Inner Mongolia high efficiency and reliable operation and generating synergy seminar, said “banks and investors are an important reason to PV misgivings, still lie in the plant’s quality, but this did not raise the power plant developer attention.”
However, according to Beijing mirror scale Certification Center on Xinjiang a 8MW PV station of sampling in the found, 3178 block PV component in the infrared imaging sampling 2856 block, which 19% exists virtual welding hot spot effect; Qinghai a 50MW PV station, sampling 44080 block PV component, found 29% PV component appeared obviously worms lines hidden crack; a domestic well-known component factory production of 1.6MW component arrival acceptance in the, sampling in the found 10% component appearance fault, 20% exists hidden crack fault ; A 10MW solar plant in Gansu province, sampling found PV module has power sharp attenuation of up to 58%. Generally speaking, the annual decay component of photoelectric conversion rate should be less than 0.8%, but the preceding performance of PV modules is far beyond the scope of this.
Non-Silicon parts quality can not be ignored
For PV module manufacturers, Silicon part is the core components from silicon materials procurement to manufacturing enterprises, each production process should implement effective quality control. But non-Silicon parts, such as back panels, borders, silver paste, junction boxes and other material effects on the quality of components should not be overlooked. Back sheet materials in particular, is one of the decisive factors of component life. Insiders pointed out that, in order to reduce initial installation cost, and shot with non-time-tested material, is intended.
It is reported that the back sheet materials that are not performance validation, and cost per watt may be between 0.01 and 0.12 Yuan can be saved, but it is only equivalent to the generating capacity of PV module 1-29 days (based on 25 years of age). Shortened life expectancy consequences may result from the power station, electricity output attenuation rate substantially. Also, may cause the internal rate of return of the power station fell from 11% per cent of expected lower to 5%.
To the Western type of 20MW solar plant, for example, as far as a 250W photovoltaic modules, using high quality backplane systems increased by the total investment ratio is extremely low. These power plants, as long as you post more days of electricity, would be sufficient to recover the cost of investment. Relative to the service life of components may be extended to up to 10 years, these costs are almost negligible.
Backplane material failure of the packaging materials within the components and the battery direct exposure in harsh outdoor environments, causing hydrolysis of packaging materials, batteries and solder corrosion and delamination problems, quickly reduce the power output and longevity, seriously it can cause insulation failures caused fire and casualty.
In fact, to ensure that the components function will not be easy. As a protective layer of PV modules, back sheet materials have survived 25 years of ultraviolet light, dust, moist and dry heat ageing factors of long-term tests. A case study of temperature, back panel needs to withstand temperatures between-40 c-85 c.
A large PV module reliability research starting in 2011, after having studied more than more than 60 global PV concludes that the photovoltaic back plate outdoor common failure there are five main types, namely, cracking, skin yellowing, cracking burning sand melted, hot spots of wear, aging acceleration power attenuation.
Original title: quality concerns “out of the way,” securitization of photovoltaic power plant