Day Four: Nobel Laureate addressed Solar Energy in a Sustainable World
Baohua Jia
A bright solar future: efficiency and cost are not the only challenges
In the first plenary session of the Congress today, the Nobel Laureate, Professor Steven Chu presented a talk on “Solar Energy in a Sustainable World”. He reminded the audience that almost all energy formats including fossil fuel, wind, fission, geothermal energy are ultimately derived from the sun. He also raised the very important but often neglected point that from system point of view the overall up-take of the solar energy depends not only on the efficiency and cost of the solar cells, as we normally concerned in the academic world. Rather, the reliability of the energy source plays a significant role. If the energy fluctuation is larger than 5%, it is unlikely for the suppliers to choose this source. This is why the current research on the highly efficient batteries is crucial for pushing solar energy as a stable main stream energy source.
Steven’s talk was very well received (the hall was full). I did think that his talk from the entire system and the supply chain point of view was very unique and helpful to revisit the challenges we are facing and to find ways to solve them. He also stressed that in order to allow large scale deployment of the solar energy, changing of the business mode is also necessary.
Image: Steven Chu's lecture
Micro-solar cells directly integrated with lens array
In a talk given by Professor Tohru Nakagawa and co-workers from Panasonic, an innovative thin and compact concentrator photovoltaic module was proposed and demonstrated. The thickness of the system is only 1/10 of the conventional concentrated photovoltaic modules and the energy conversion efficiency can be as high as 34.7%. This attractive technology has the great potential to make the concentrated photovoltaic devices more cost-effective.
Image: Micro-solar cells with integrated lens array (image from Jpn. J. Appl. Phys. 53, 04ER01 (2014))
Close of the Congress
The Congress was closed today after a busy and exciting four-day program. I enjoyed the Congress very much but I had to say goodbye to my colleagues and friends for now. With all the interesting ideas and encouraging results I heard from the Congress, I am now more confident and delighted to work in this field. And I would like to pass on these positive messages to my colleagues/friends back to my University. I am pretty sure many of the attendees will do the same thing.
