Research seminar Solar energy harvesting with the application of nanotechnology

Transcription

1 Research seminar Solar energy harvesting with the application of nanotechnology By B.GOLDVIN SUGIRTHA DHAS, AP/EEE SNS COLLEGE OF ENGINEERING, Coimbatore

2 Objective By TW The fossil fuels will exhausted in the near future Global warming 2

3 Contents Introduction Nanotechnology for harvesting solar energy Active solar systems Solar collector Fuel cell Photocatalysis Solar photovoltaic/thermal Energy storage Rechargeable batteries Supercapacitors Passive solar systems Phase change materials (PCMs) Glazing Paint Solar cell technologies First generation solar cell technologies Second generation solar cell technologies Third generation solar cell technologies 3

4 Nanotechnology Richard Feynman in 1959 Norio Taniguchi- nanotechnology mainly consists of the process of separation, consolidation, and deformation of materials by one atom or one molecule. Dr. K. Eric Drexler Molecular Nanotechnology (MNT) 4

5 Nanotechnology Dimensions between 1 and 100 nm are known as the nanoscale Diameter of an atom 0.1nm 5

6 Nanotechnology Diameter of an atom 0.1nm 6

7 Nanotechnology Carbon nanotube The resistivity 10 4 ohm-cm at 27 C. The current density was 10 7 A/cm 2. The current Young s modulus is about 1 Tpa. superconductivity below 20 o K 7

8 Nanotechnology Nanotechnology - new industries based on cost-effective and cost-efficient economies -a sustainable economic growth. on the energy domain - impact of energy production, storage and use. 8

9 Active solar systems To convert solar energy into the other more useful forms of energy Solar collector, fuel cell, photocatalysis, solar photovoltaic/thermal 9

10 Solar collector Heat exchangers 10

11 Solar collector Line Focus Collectors Point Focus Collectors 11

12 Solar collector absorbing medium water water with high thermal conductivity fluids Therminol VP-1 an ultra-high temperature synthetic heat transfer fluid water with Nanofluid fluid containing suspended solid nanoparticles 12

13 Nanofluid Examples water carbon nanotube (H 2 O-CNT) water TiO 2 (H 2 O-TiO 2 ) water based CuO nanofluid carbon nanotubes, graphite silver Al 2 O 3 aluminum nanoparticles in Therminol VP-1 13

14 Nanofluid Inference 10% improvement in efficiency volume fractions of nearly 0.001% a volume fraction higher than 2%, the efficiency remains nearly constant weight concentration 0.5% - excellent light heat conversion reduced temperature 14

15 Fuel cell low emission and high efficiency Membrane, electro-catalyst and electrode Nanoparticle proton exchange membrane fuel cells (PEMFCs) direct methanol fuel cells (DMFC) multi-wall carbon nanotube (MWNT) 15

16 Fuel cell Metal oxide anode Silicon nanorod cathode 16

17 Fuel cell Examples MnO2/SiO2 SO3H nanocomposite into the Nafion membrane Nafion is a sulfonated tetrafluoroethylene based fluoropolymer-copolymer 17

18 Fuel cell 10% higher fuel cell voltage and twice the power density improves fuel cell performance and membrane durability low humidity conditions.» Stable, active, high specific surface area and good electric conductivity. 18

19 Photocatalysis 19

20 Photocatalysis 20

21 Solar photovoltaic/thermal Convert solar energy into heat and electricity at the same time. 21

22 Solar photovoltaic/thermal The overall efficiency of the PV/T system is beyond 60% Example P 3 HT/CdS/CdSe/TiO 2 22

23 Energy storage The use of electricity generated from renewable sources, such as water, wind, or sunlight, requires efficient distributed electrical energy storage on scales ranging from public utilities to miniaturized portable electronic devices. 23

24 Rechargeable batteries nanotubes + cellulose = paper battery first electrode - carbon nanotubes on Si substrates. Plant cellulose with an ionic liquid form porous separator. second electrode is formed by coating the paper side with lithium oxide. 24

25 Supercapacitors Nanotubes increase the power density of supercapacitors, offer a unique combination of low electrical resistivity and high porosity specific power density of 30 kw/kg in Nanotubes 4 kw/kg in commercial 25

26 Passive solar systems spread solar energy in the form of heat in the winter and decline solar heat in the summer. windows, walls, and floors 26

27 Phase change materials As the temperature increases, PCMs change phase from solid to liquid and viseversa. organic, inorganic and eutectic. 27

28 Glazing metal to semiconductor transition Vanadium dioxide antireflection coating sun protecting glazing with infrared reflecting nanolayers 28

29 Paint TiO 2 pigmented paints are the best for radiative cooling applications FeMnOx is the best paint pigment so far for solar thermal applications 29

30 Solar cell technologies First-generation solar cell (fully commercial) wafer-based crystalline silicon (c-si) technology Second-generation solar cell (early market deployment) thin-film solar cell technologies Third generation solar cells (under research & demonstration) concentrating and organic solar cells 30

31 Solar cell technologies First-generation solar cell single crystalline (sc-si) or multi-crystalline (mc-si). Second-generation solar cell amorphous (a-si) and micromorph silicon (a-si/μc- Si); Cadmium Telluride (CdTe); and Copper Indium Selenide (CIS) and Copper Indium Gallium Diselenide (CIGS). 31

32 Third-generation Quantum dots enhance light absorption via multiple energy levels and extend the absorption edge into the infrared range ability to absorb different wavelengths of light from sunlight Nanoparticle of titanium oxide (TiO2) and zinc oxide (ZnO2) Efficiency upto 64% 32

33 Third-generation Quantum wells QWs are formed in semiconductors by materials such as gallium arsenide (GaAs) sandwiched between two layers of a material with a wider band gap, like aluminum arsenide (AlAs) QWs within the solar cells manage charge carriers electrons and holes (e h) that usually swing in three dimensions to two dimensions. Efficiency upto 36% 33

34 Third-generation Smart' coatings Electrochromic and electrophoretic or suspendedparticle windows seem highly promising for dynamic daylight and solar energy applications in buildings ITO covering on glass provides more than 80% indication for the wavelengths prevalent in the sunshine. 34

35 Solar cell technology status and prospects 35

36 Elsevier Renewable and Sustainable Energy Reviews 26(2013)

37 Thank You 37