Journal of Nanomedicine & Nanotechnology

Novel black selective solar absorbers for high temperature concentrated solar power applications

7^th World Nano Conference

June 20-21, 2016 Cape Town, South Africa

Malik Maaza

UNESCO-UNISA Africa Chair in Nanosciences-Nanotechnology, South Africa iThemba LABS-National Research Foundation, South Africa

Keynote: J Nanomed Nanotechnol

Abstract:

The most significant concern of our world today is the energy derived mainly from fossil fuel which exceeds 87 % both in advanced & developing economies including African nations. A shift towards greener energy technologies has produced energy changes worldwide; Africa included. In view of the large direct normal solar irradiation in the continent (average of 220 W/m2 in Africa against 150 and 100 W/m2 in the USA and Europe respectively), several African nations have embarked in large solar energy parks and programs. One could quote Morocco and South Africa specifically with a target of 3.7 GW and 5 GW at Ourzazat and Upington solar parks respectively. There are 2 major solar energy technologies: the Photovoltaics (PVs) & the Concentrated Solar Power (CSP). While the PVs are dominated by household & small to average businessesâ?? usage, the CSP is geared towards high throughput and grid based consumption. In the CSP plants, known also as solar photo-thermal power plants, the electricity is produced in much the same way as conventional power stations. The difference is that they obtain their energy input by concentrating solar radiations and converting them to high temperature steam or gas to drive a turbine/engine. More precisely, the incoming radiations are reflected by parabolic mirrors which concentrate the solar energy towards a selective solar absorber coatings deposited on metallic tubes. Hence, the most important and critical part of the solar collector is the black selective absorber surface itself, which should absorb a maximum of solar radiations & convert them into heat, which in its turn transferred to the heat transfer fluid. In this sense, 6 configurations of the black selective solar absorber nano-coatings can be adopted technologically: (1) intrinsic, (2) semiconductor-metal tandems, (3) multilayered absorbers, (4) multi-dielectric composite coatings, (5) textured surfaces, and (6) selectively solar-transmitting coating on a blackbodylike absorber. This contribution reports on recent advances in novel class of selective solar absorber nanostructures for high temperature CSP applications.

Biography :

Prof. M. Maaza is currently a permanent staff member of the National Research Foundation of South Africa (NRF). Among other positions held, he was the Southern Africa representative of the International Commission of Optics (ICO-CIO) and Vice-President of the National Council of Scientists & Engineers of France: Section South-Africa (CNISF). He is the chair of the ICSU-UNESCO-UNIDOTWAS supported official Nanosciences African Network (NANOAFNET), and southern Africa coordinator of the African Physical Society (AfPS) as well as a member of the board of the directors of the African Laser Centre (ALC). He is the South Africa representative of the African Lasers, Atoms & Molecules Network (LAMNETWORK). He was and is the Southern Africa contact point of the Japan- South Africa S&T cooperation and ICS-UNIDO respectively in nanosciences-nanotechnologies. He has been recently elected as the Africa representative in the EU funded nanosciences-nanotechnologies international initiative (ICPCNANONET) and COST action 702. Prof. Maaza has been instrumental in pioneering and implementing numerous currently successful ongoing continental and national official initiatives amid which the African Laser Centre, the Nanosciences African Network, the National Laser Centre of South Africa (NLC SA) and the South African Nanotechnology initiative (SANi). Prof. Maaza is the current UNESCO UNISA Africa Chair in Nanosciences & Nanotechnology via a trilateral partnership between UNESCO, NRF and the University of South Africa (UNISA). He is in charge of the Africa-International relations desk officer at iThemba LABS-National Research Foundation of South Africa. He is extraordinary professor at the Tshwane- Pretoria University of Technology and an associate scientist of the US National Science Foundation Centre of Excellence in Nanosciences-Clark Atlanta University. He is a fellow of the African Academy of Sciences, Royal Society of Chemistry, New York Academy of Sciences & the Islamic Academy of Sciences. His expertise is in the multidisciplinary field of nanosciences, photonics and solar energy. He has published more than 250 ISI publications and supervised several postgraduates from Africa.

Email: likmaaz@gmail.com