This group of scientists in the picture is the Atwater Research Group and they have a huge name behind them, Prof. Harry Atwater. The Atwater Research Group has been working on multiple areas, including photovoltaics, since 1988, when Prof. Atwater joined Caltech. About 25 years of experience, many awards & honors, and consistent success in photovoltaics made Prof. Atwater one of the huge names in this field.
Currently, the Atwater Research Group works on materials science problems, solid state & device physics, and functional materials & devices. The team categorizes their projects under different titles including, what we will cover in our review, Thin Film Photovoltaics.
Thin Film Photovoltaics
In Photovoltaics, semiconductor materials are used to produce electricity from sunlight. Currently, the photovoltaics market is dominated, over 80%, with Crystalline Silicon solar cells due to its optimum cost effectiveness & efficiency. However, with the current structure, Crystalline Silicon solar cells cannot compete with the fossil based energy solutions from cost perspective. Therefore, Atwater Research Group sees the future of photovoltaics with inexpensive thin film devices and processes and lists amorphous silicon (a-Si), copper indium diselenide (CIS) and cadmium telluride (CdTe) as the possible replacements for Crystalline Silicon.
The team targets two emerging research areas under this topic, Crystalline Si Thin Films & III-V Heterostructures.
Crystalline Si Thin Films is, as the name implies, a combination of Crystalline Silicon & Thin Film solar cell technologies. Recognizing the fact that the Crystalline Silicon is the most commonly produced, used, and well-known solar cell technique; Atwater Research Group is trying to create thin Crystalline Silicon films (1-30 microns) on another, a lot less expensive material. The result of this effort could significantly lower the cost associated with Crystalline Silicon deployments.
III-V Heterostructures effort is one of the most important projects we have covered in our website. The most efficient, but also the most expensive, solar cells are made with Multijunction Cell technique, as seen in the graph below. This graph is from National Renewable Energy Laboratory (NREL) and the most recent version can be seen by clicking on this link. Keep in mind that SHARP recently broke the highest efficiency record with a 44.4% efficient triple-junction solar cell, as we covered in our website (click here to read more about the triple-junction solar cell record). The graph below has not been updated with that development as of the writing of this review.
One of the strongest entities breaking efficiency records in recent years is Alta Devices. They hold the 28.8% efficiency record for single junction thin film crystal cells. Alta Devices has a huge name behind them as a co-founder, the same name that the Atwater Research Group has, Prof. Harry Atwater.
The Atwater Research Group, as a part of this effort, works on creating a low cost material to be used in multi-junction solar cells. With the current structure, as we mentioned earlier, the multi-junction solar cell solutions are too expensive to be used in house-holds or industry. The main use of these cells is in space-crafts.
With Prof. Atwater’s success in the single-junction solar cells area, his work on multi-junction solar cells is very promising. Towards the end of 2012, the Advanced Research Projects Agency-Energy (ARPA-E) awarded Prof. Atwater with $2.4 million to be used in this research effort. Prof. Atwater’s team is not aiming to increase the 44.4% efficiency record, they are aiming to create a jump to 50-70% efficiency levels.
Prof. Harry A. Atwater, Jr.
Prof. Harry Atwater has many hats. He is the Director of the Resnick Institute; Director of the Light-Material Interactions Energy Frontier Research Center (LMI); and Howard Hughes Professor and Professor of Applied Physics & Materials Science at California Institute of Technology (Caltech). He received his B.S. (1981), M.S. (1983), and Ph.D. (1987) degrees all from Massachusetts Institute of Technology (MIT) Electrical Engineering department. A year later, in 1988, Prof. Atwater joined Caltech and he has been a faculty member since then.
Even though he has been working on renewable energy projects for about 25 years, Prof. Atwater’s interest in this field did not start with his academic career. Back in elementary school in 1970s, in Pennsylvania, schools would close for extended periods of time in winter due to fuel shortage. This was the turning point of Prof. Atwater’s career.
His consistent & successful work in renewable energy field earned Prof. Atwater many awards & honors including:
- ENI Award – Renewable and Non-Conventional Energy (2012)
- SPIE Green Photonics Award (2012)
- MRS Fellow (2011)
- MRS Kavli Lecturer in Nanoscience (2010)
- Popular Mechanics Breakthrough Award (2010)
- Joop Los Fellowship – Dutch Society (2005)
- AT&T Foundation Award (1990)
- IBM Faculty Development Award (1989-1990)
- NSF Presidential Young Investigator Award (1989)
Prof. Atwater is the co-founder of two companies; Aonex Corporation and Alta Devices, which is well known for their single junction crystal thin film solar cell efficiency records. He is also the name father of the Plasmonics field (click here to read the Scientific American article by Prof. Atwater, “The Promise of Plasmonics”). Prof. Atwater has published or co-published over 400 articles throughout his career.
Video clips that involve Prof. Atwater are also available online:
To learn more about Prof. Atwater and his team, visit their website by clicking on this link.