PV module market around the world have been cost driven and it is no wonder that the crystalline technology has been the chalk horse of the industry. Further, with the levelized cost of electricity (LCOE) from solar plants have started breaching grid parity, the focus now is to extract maximum kWh from the plant in order to ensure the investors have maximized returns. The technology upgradation in conjunction with module design upgradation has played a significant role in such shift. Utilization of bifacial module which are capable of generating power from both sides has been gaining traction, given the fact that enhanced energy output could be expected under right designing considerations. However, the currently available bifacial module utilizes PERC/PERT crystalline solar cells which have limited bifaciality coupled with other inherent issues like LID, PID, LeTID, etc. It was hence necessary to bank upon a pragmatic solution.

Silicon heterojunction (HJT) solar cell which has been introduced in the mid-19^th century, utilizes both crystalline and thin film technology. The cell has a crystalline silicon (n-type) sandwiched between amorphous (thin film) layers of silicon on both the sides, giving the cell its bifacial nature. The mono crystalline technology in the cell has better absorption of light whereas the amorphous has superior passivation (which enables high electron collection) characteristics. The cells are thinner (~120 μm) compared to crystalline silicon cell making it slightly flexible and further also making them highly resistant to micro-cracks. The n-type silicon present in HJT does not have Boron, which makes these cells LID free. Further the mitigation of electron from solar cell which are responsible for PID are also reduced to zero in HJT cells, thanks to the presence of highly conductive oxide layer (ITO) which protects the cell electrically. Additionally the cell has a lower temperature coefficient (almost half of the crystalline technology based cells). All the above factors when coupled together enables HJT based module to have lower degradation rates throughout its lifetime.

The role of PSU's in enabling India to meet its renewable energy targets

India has set an ambitious target of meeting 175GW of its power demand by renewable energy in 2022. While there has been a lot of improvement from its state of cumulative capacity in early 21^st century. From that state the sector has seen a lot of government intervention and private partnerships in order to establish and develop a solar power plant in the country. A new plan by the government (yet in draft version) would enable Public Sector Undertaking (PSU) companies to utilize and/or source green energy. The plant shall likely be 1.8 GW of capacity (similar to coal based ultra-mega power projects (UMPPs)) and may be divided into 3 parts. The country already has a plan to develop 12GW of power plant through the PSU route. While there has been cases of tender cancellation in various states citing various reasons, we believe that the role of government in fuelling the solar PV market growth is crucial.

Cumulative & Expected capacity addition

Cumulative & Expected capacity addition of solar energy in India by 2022

Health benefits from Renewable energy sources implementation estimated!

Implementing renewable energy sources for meeting the enhancement in demand of the world is a no brainer now. However, it is also a well-known fact that renewable energy comes with environmental advantages too! A recent study titled “Health co-benefits of sub-national renewable energy policy in the US” reviews the health benefits of implementing renewable source in Rust Belt, US. The study compares impacts of renewable portfolio standards (RPS) on air quality and human health. The study compares business as usual (BAU) RPS case along with enhanced RPS cases of +50% & +100% and finally the case of pricing CO₂ emissions to no renewable energy implementation by 2030. The study finds that the co-benefits of the BAU, RPS + 50%, and RPS + 100% scenarios correspond to co-benefits of 8¢, 12¢, and 13¢ per kWh of new renewable generation (or $94, $120, $119 per ton of CO2 reduced respectively). The study further suggest that CO₂ emission pricing shall further have a positive impact with a health benefit realized up to $211 per ton of CO2 reduced. The study concludes by finding that health co-benefits in the region were 35%–79% higher depending on the RPS scenario. We believe that for a country like India which has ambitious missions like 24x7 Power for all and Health for all, studies like such should be taken into consideration by the policy makers to enable implementation of right sources.

Cost benefits from implementing renewable energy sources under different scenarios in 2030 comparing to no renewables implementation (Source: Emil G Dimanchev et al 2019 Environ. Res. Lett. 14 085012)

The state of solar grid parity in China and takeaways for India

Solar PV has gained a tremendous popularity around the world and China is amongst the top leader in the market. The country had both supporting government policies and attractive upfront subsidies for PV making it one of the competent source of electricity in the past few years. However, with the country (and many countries around the world) breaching the grid parity, the dynamics are poised to be changed. A new study titled “City-level analysis of subsidy-free solar photovoltaic electricity price, profits and grid parity in China” and published in “Nature Energy” reviews the situation of China. The study analysed more than 344 prefecture-level Chinese cities and finds that all these cities without any subsidy in solar PV, can meet grid parity. Further with the country also being a coal powered giant and utilizing desulfurized coal (which emits lower emission) for power production; the study finds that around 22% of the cities can produce electricity which can match prices of such sources. The subsidy cuts in recent years was also a clear note that PV industry now needs to be focused on quality products rather than on the scale. While economies of scale has been instrumental in the case of India, very often it is forgotten that the solar PV plant are to last for 25 years which makes quality a crucial factor of review. We believe that the utility/customers which are only utilizing quality products would be able to reap the long term benefits of solar PV.

(From left) Historical LCOE of solar PV generation in China and (right) LCOE of various generating sources (Source: Yan J., et al. City-level analysis of subsidy-free solar photovoltaic electricity price, profits and grid parity in China. https://doi.org/10.1038/s41560-019-0441-z)