Solar Team Awarded Queen Elizabeth Prize for Engineering Excellence

The winners of the 2023 Queen Elizabeth Prize for Engineering have been announced

This year’s Prize for Engineering has been awarded to a group of scientists who developed a new type of solar technology called Passivated Emitter and Rear Cell (PERC). The 10th-anniversary award marks a significant milestone, over the past decade, QEPrize has honored 20 engineers whose innovations have had a significant impact on billions of lives around the world.

https://www.youtube.com/watch?v=lNXWML9TEww

The team – Martin Green, Andrew Blakers, Jianhua Zhao and Aihua Wang – work has greatly improved the efficiency of solar cells, making them more powerful and cheaper to produce. This breakthrough has helped make solar the most affordable source of electricity in most countries.

The history of solar technology goes back over 180 years, but it wasn’t until the 1970s that commercial production began. In the early 1980s, the efficiency of solar cells was around 14%, but Martin-Green, Andrew Blakers, Aihua Wang, and Jianhua Zhao, among others, set out to improve that. They found a way to increase the efficiency of solar cells by adding an extra layer to the back of the cell, which prevented the loss of photon-generated electrons.

What is PERC ( Passivated Emitter and Rear Cell )

Passivated Emitter and Rear Cell (PERC) is a solar photovoltaic technology that has revolutionized the field of solar power generation. The technology is characterized by its ability to significantly boost the efficiency of solar cells, making it the most commercially viable silicon solar cell technology available.

In most solar cells, efficiency is limited by photon-generated electrons being lost through recombination with the thick doped silicon layer at the back surface. To overcome this, PERC introduced an additional layer on the back surface that helped prevent recombination and further reflected unused photons back into the silicon to generate more electrons.

This has been achieved through the use of a thin layer of passivation material, typically silicon dioxide, that was placed between the silicon substrate and the rear contact. This passivation layer effectively blocked any recombination of the electrons, reducing losses and improving overall efficiency.

This is because the rear contact of PERC cells is designed to be more reflective than conventional cells. By reflecting unused photons back into the cell, more electrons are generated, leading to higher efficiency.

The use of PERC technology has led to a significant increase in solar cell efficiency, with conversion rates of up to 25% being achieved. This has made solar power generation more viable and economically competitive with other forms of energy.

The introduction of PERC technology has led to exponential growth in high-performance, low-cost solar electricity, making it the cheapest source of electricity in most countries and has made significant contributions to the shift towards zero emissions electricity.

Who Won the 2023 Queen Elizabeth Prize for Engineering?

The team’s work led to the development of PERC technology, which has become the most commercially viable silicon solar cell technology in use today, accounting for almost 90% of the global solar cell market.

This year’s award recognized:

Martin Green

Martin Green has trained many successful solar panel entrepreneurs and technical leads in solar panel companies. He is currently working on trying to further improve solar cell efficiency by stacking cells that respond to different parts of the solar spectrum.

Andrew Blakers

Andrew Blakers is working on pathways to 100% renewable energy futures, including identification of vast energy storage potential to support variable solar and wind generation through a global atlas of 600,000 sites for off-the-shelf gigawatt-scale pumped hydro storage.

Jianhua Zhao and Aihua Wang

Dr Jianhua Zhao and Dr Aihua Wang hold the record for the world’s most efficient silicon solar cells. They spent nearly 15 years working and teaching at the UNSW before returning to China in 2004, where they continued their incredibly successful partnership at China Sunergy. They have published over 117 conference papers and 66 journal papers, including in Nature.

However, the Queen Elizabeth Prize also recognized that the road to PERC had many other people contribute to the technology. While they were not recognized by the award the QEP did note the contributions of:

Stuart Wenham

Stuart Wenham pioneered work on hydrogenation to neutralize defects introduced during PERC cell manufacturing and field operation. He was also a pioneer in the laser processing used in commercial PERC cells.

Dick Swanson

Dick Swanson at Stanford University and his team contributed groundbreaking improvements to interdigitated back contact cells, which contributed greatly to the development of highly efficient laboratory and commercial solar cells.

Pierre Verlinden

Pierre Verlinden at Louvain and his team contributed greatly to the development of interdigitated back contact cells, which contributed greatly to the development of highly efficient laboratory and commercial solar cells.

It is important to remember that while Solar technology is being introduced across national electricity grids worldwide, the technology has been transformative in smaller settings like towns and farms across low- and middle-income countries.

The work of these Engineers has had a huge impact and brought us one step closer to a more sustainable future.