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Projects: Projects for Investigator
Reference Number EP/G042330/1
Title Science Bridge Award USA: Harnessing Materials for Energy
Status Completed
Energy Categories Renewable Energy Sources(Solar Energy, Photovoltaics) 45%;
Energy Efficiency(Residential and commercial) 45%;
Energy Efficiency(Transport) 10%;
Research Types Basic and strategic applied research 100%
Science and Technology Fields PHYSICAL SCIENCES AND MATHEMATICS (Physics) 30%;
PHYSICAL SCIENCES AND MATHEMATICS (Metallurgy and Materials) 40%;
ENGINEERING AND TECHNOLOGY (Mechanical, Aeronautical and Manufacturing Engineering) 30%;
UKERC Cross Cutting Characterisation Not Cross-cutting 100%
Principal Investigator Professor CJ Humphreys
No email address given
Materials Science & Metallurgy
University of Cambridge
Award Type Standard
Funding Source EPSRC
Start Date 13 April 2009
End Date 12 October 2012
Duration 42 months
Total Grant Value £1,447,635
Industrial Sectors Electronics
Region East of England
Programme Energy : Infrastructure
Investigators Principal Investigator Professor CJ Humphreys , Materials Science & Metallurgy, University of Cambridge (99.996%)
  Other Investigator Professor AK Cheetham , Materials Science & Metallurgy, University of Cambridge (0.001%)
Professor I White , Engineering, University of Cambridge (0.001%)
Dr V Deshpande , Engineering, University of Cambridge (0.001%)
Professor Sir R Friend , Physics, University of Cambridge (0.001%)
Web Site
Abstract This Science Bridge proposal builds upon the existing collaboration between the University of Cambridge and the University of California at Santa Barbara to perform the research required to bring existing research through to prototype products and devices in the field of energy-related materials. The proposal has five key themes: organic and inorganic solar cells; light emitting diodes (LEDs) based on gallium nitride (GaN); phosphors for solid-state lighting; organic LEDs (OLEDs); the low-costintegration of LEDs and OLEDs onto printed circuit boards; and ultralight materials and structures.An hour of solar radiation on the Earth provides 14 Terawatt-years of energy, almost the same as the world's total annual energy consumption. However, currently solar energy contributes only 0.03% of the world's energy needs, the main barriers to the widespread use of solar energy being cost and efficiency. The cost of solar cells (typically based on Si or CdTe) is currently too highby a factor of ten relative to other energy sources. The efficiency of solar cells is only 10-15% for Si and 20% for CdTe. We propose two approaches to make solar energy more viable. First, we propose to develop moderate-efficiency (about 15%) organic solar cells at extremely low-cost. UCSB will concentrate on developing more efficient cells and Cambridge will address low-cost manufacturing methods. This requires significant advances in printing methods for organic film deposition.The other approach to solar cells we will pursue is high-efficiency inorganic multilayer solar cells. The basic idea is that by stacking layers in the order of their bandgap, with the layer with the largest bandgap at the top, light is converted into electricity in the most efficient way. We propose to build an innovative multi-layer solar cell based on GaN/InGaN/Si. The GaN layer will absorb the UV part of the solar spectrum, the InGaN layer the blue and green parts and the Si layer the yellow, red and near-IR parts. The theoretical efficiency is above 60%. Such a cell would be too expensive for large-area applications, but would be designed to be used at the focus of mirrors that concentrate the solar light, which will make the technology competitive.GaN-based white lighting is extremely efficient and if used in our homes and offices it could save 15% of the electricity generated at power stations, 15% of the fuel used, and reduce carbon emissions by 15%. Howeverfor GaN-based white lighting to become widely used in homes and offices we have to increase the efficiency still further and reduce the cost. We will research various ways to increase the efficiency. To reduce the cost we will grow GaN-based LED structures on 150mm (six-inch) silicon wafers instead of the current growth on two-inch sapphire wafers. This would reduce the LED cost by a factor of ten. Cambridge will grow such LED structures and UCSB will process them into LED lamps.Current whiteLEDs mainly use a blue LED coated with a yellow phosphor, which gives a cold white light. We will research novel phosphors which give excellent colour rendering, so that skin tones, the colour of clothes, etc, look the same indoors and out. There is increasing evidence that such natural lighting is better for our health than poor quality artificial lighting. We will research OLEDs for large area applications in both displays and lighting. We will also develop the low-cost integration of bothLEDs and OLEDs onto printed circuit boards, which will facilitate and reduce the cost of using LEDs and OLEDs.Finally, we will develop novel ultralight materials and structures for use in cars, buses, lorries, trains and planes. These are cellular materials like a honeycomb or 3D lattice. We will develop these using both polymers, metals and composites. Such ultralight materials/structures should save considerable amounts of energy when used in transportation systems such as cars, buses, trains and planes
Publications (none)
Final Report (none)
Added to Database 23/12/08