Solar Energy Potential

Solar Energy Potential Themetual 1.2X10 5 TW St potential 1.76 x105 striking Earth; 0.30 global mean albed, Energy in 1hr - 14Th for year Practical 2 GOOTW 8EP (50TW-1500TW depending on land fraction production WEA 2000 Onshone electricity generation potential of 260th (10% conversion efficiency Phstssynthesis SE conversion devices Methods of tapping silar energy A. Photosynthesis; plants, visible light A=2-4% B. Water heaters ; that plate, tube; IR C. PV cells ; p/n Si, Si, GaAs ; Visible; 2=12-261 D. chemical routes I D2 PEC cells DI Biomimetism minicking DS AXX so D2. a. LISC (i) Sc/Elect/M 2-13-14% (i)) 12.0.01% (1) b. Phila assisted Photoelectrosynthesis electrolysin ( PES) cells cells 22 13.3% (ii) Photoassisted eledrosynthesis cells eg. CO2- 7 CH2OH ,N2 NH3

PV cells Device that converts the energy of sunlight directly into electricity by PV effect. PV effect involves creation of a voltage (or a corresponding electric current) in a material upon exposure to em radiation. preffect related to P.E ffect , both different Types, all use SC to interact with incoming an pristons from Sun in order to generate electric current. is purified (Se) from sand, quartz, at etc "doped" Highly with intentional impunities controlled concentrations often used in PV cells why Silicin? Considerameot suitable for SE conversion cause; 2nd most abundant (N28% by mass) after O2 1 Si can be readily synthesized from in furnace. sand or pure quartz by heating them at T temp sit Co2 SiO2 + C Excellent SC with optimum band gap of 1.23eV at 300K. Cost effectiveness easily doped with P, As, Sb, B, In, Al