bjorseth

Energy and Computation: Flops/Watt and Watts/Flop Solar Cell ScalingThe Center for Bits and Atoms - MIT: 

Energy and Computation: Flops/Watt and Watts/Flop Solar Cell Scaling The Center for Bits and Atoms - MIT Dr. Alf Bjørseth Scatec AS May 10th, 2006

Alf Bjorseth: 

Alf Bjorseth Ph.D. in physical chemistry – University of Oslo, Norway Section Manager, Battelle Columbus Labs. Adjunct Professor, Industrial Chemistry, Univ. of Bergen, Norway Corporate director of R&D – Norsk Hydro Director of Technology – Elkem Founded SCATEC - PhotoCure (Photodynamic therapy) - Renewable Energy Corporation (REC) (IPO May 9th ‘06)

Global energy consumption 1850 - 2030and CO2 emmissions 1970 - 2020: 

Global energy consumption 1850 - 2030 and CO2 emmissions 1970 - 2020

Slide4: 

Mtoe Source: IEA WEO 2002 Growth in global energy consumption

Slide5: 

The Sun daily provides about 10 000 times more energy to the Earth than we consume Photovoltaic technology directly converts solar energy into electricity No moving parts – no noise – no emissions – long lifetime Large industrial potential - cost reductions needed Feedstock for PV industry is silicon - the second most abundant element in the crust of the Earth The Sun as Energy Source

Slide6: 

Global Energy Situation

Future energy mix: 

Future energy mix

Slide8: 

Main Application Areas – Off-grid

Slide9: 

Main Application Areas Grid Connected

Solar Energy status: 

Solar Energy status Market is exploding The solar industry is very profitable Lack of highly purified silicon (polysilicon) Cost of solar electricity is too high, R&D focus on reducing cost and increasing efficiency

Solar Energy status: 

Solar Energy status Market is exploding The solar industry is very profitable Lack of highly purified silicon (polysilicon) Cost of solar electricity is too high, R&D focus on reducing cost and increasing efficiency

Slide12: 

Actual Growth vs. Historic Forecasts

Solar Energy status: 

Solar Energy status Market is exploding The solar industry is very profitable Lack of highly purified silicon (polysilicon) Cost of solar electricity is too high, R&D focus on reducing cost and increasing efficiency

Slide14: 

RECs - Gross revenue development

Slide15: 

RECs - EBITDA development (MNOK)

Solar Energy status: 

Solar Energy status Market is exploding The solar industry is very profitable Lack of highly purified silicon (polysilicon) Cost of solar electricity is too high, R&D focus on reducing cost and increasing efficiency

Solar Grade Silicon Supply-Demand (MT/year): 

Solar Grade Silicon Supply-Demand (MT/year)

Solar Energy status: 

Solar Energy status Market is exploding The solar industry is very profitable Lack of highly purified silicon (polysilicon) Cost of solar electricity is too high, R&D focus on reducing cost and increasing efficiency

Cost reductions – existing technologies: 

Cost reductions – existing technologies Thinner wafers - Wire sawing - Laser cutting and etching Higher efficiencies - Semiconductor technologies on single crystal wafers (examples Sanyo / SunPower) Thin film technologies (flat panel display)

Slide20: 

Public incentives are important

Cost goals for third generation solar cells: 

Cost goals for third generation solar cells Efficiency and cost projections for first-, second- and third generation photovoltaic technology (wafers, thin-films, and advanced thin-films, respectively) Source: University of New South Wales

Next generation technology: 

Next generation technology Silicon nanostructures Bandgap engineering of silicon. Applications could be tandem solar cells and energy selective contacts for hot carrier solar cells. Fabrication of silicon nanostructures consisting of quantum well and quantum dot super lattices to achieve band gap control

The energy band structure for silicon: 

The energy band structure for silicon

Slide24: 

Up/Down converters Luminescent materials that: EITHER absorb one high energy photon and emit more than one low energy photon just above the bad gap of the solar cell (down-conversion) OR that absorb more than one low energy photon below the band gap of the cell and emit one photon just above the band gap (up-conversion). Next generation technology (cont.)

Understanding cell efficiency : 

Understanding cell efficiency

Slide26: 

Hot carrier Cells This concept tackles the major PV loss mechanism of thermalisation of carriers. The purpose is to slow down the rate of photoexcited carrier cooling caused by phonon interaction in the lattice to allow time for the carriers to be collected whilst they are still hot, and hence increasing the voltage of a cell. Next generation technology (cont.)

Slide27: 

Thermoelectric solar cells Application of the concept of energy –selective electron transport used in hot carrier solar cells, to develop thermo electrics and thermo-ionics devices. Next generation technology (cont.)

Slide28: 

Solar energy will become the most important and cost-efficient energy source in the future. The present lack of silicon feedstock is promoting a rapid development of next generation technology. Immediate actions are taken to cut thinner wafers and increase cell efficiencies for crystalline silicon. New thin film technologies are being developed Stronger influence from semiconductor industry will accelerate the development of better technologies Nanosilicon and other third generation technologies may offer a long-term solution for the future solar energy technology. Conclusions

Thank you for your attention: 

Thank you for your attention The Photovoltaic industry has taken off…

Schrödinger wave equation: 

Schrödinger wave equation

Solving Schrödinger equation;  use of Bloch functions: 

Solving Schrödinger equation; use of Bloch functions

Slide32: 

The PV Value Chain (multi-crystalline)

California solar initiative installations and rebate level targets (2006E- 2016E): 

California solar initiative installations and rebate level targets (2006E- 2016E) Source: California Public Utilities Commission

Prices are actually increasing: 

Prices are actually increasing