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Solar energy is special. It is vast, ubiquitous and indefinitely sustainable. The solar resource is much larger than all other available energy resources combined. Solar energy utilises very common materials; has minimal security and military risks; is available nearly everywhere in vast quantities; and has minimal environmental impact over unlimited time scales. No other energy source can make claims that come anywhere near these. Solar energy is a complete long term sustainable solution. The recent (and continuing) rapid price reduction in photovoltaics and wind energy was not generally foreseen, and is likely to lead to widespread market disruption. New wind and solar photovoltaic (PV) systems are both being deployed around the world in similar scale to new coal, gas and hydro systems. Renewable energy now constitutes the majority of new generation capacity installed each year. Electricity from wind and PV systems is now cost-competitive with new-build coal, gas, oil and nuclear generators in many parts of the world. Roof-mounted PV systems successfully compete with conventional gas and electricity for the supply of heat and electricity in cities. Transport and chemical synthesis powered by PV and wind electricity is likely to be competitive in the future.

Solar energy is special. It is vast, ubiquitous and indefinitely sustainable. The solar resource is much larger than all other available energy resources combined. Solar energy utilises very common materials; has minimal security and military risks; is available nearly everywhere in vast quantities; and has minimal environmental impact over unlimited time scales. No other energy source can make claims that come anywhere near these. Solar energy is a complete long term sustainable solution. The recent (and continuing) rapid price reduction in photovoltaics and wind energy was not generally foreseen, and is likely to lead to widespread market disruption. New wind and solar photovoltaic (PV) systems are both being deployed around the world in similar scale to new coal, gas and hydro systems. Renewable energy now constitutes the majority of new generation capacity installed each year. Electricity from wind and PV systems is now cost-competitive with new-build coal, gas, oil and nuclear generators in many parts of the world. Roof-mounted PV systems successfully compete with conventional gas and electricity for the supply of heat and electricity in cities. Transport and chemical synthesis powered by PV and wind electricity is likely to be competitive in the future.

Solar energy is special: It is vast, ubiquitous, and indefinitely sustainable. The solar resource is much larger than all other available energy resources combined. Solar energy utilizes very common materials; has minimal security and military risks; is available nearly everywhere in vast quantities; and has minimal environmental impact over unlimited time scales. The recent (and continuing) rapid price reduction in photovoltaics and wind energy was not generally foreseen, and is likely to lead to widespread market disruption. New wind and solar photovoltaic (PV) systems are both being deployed around the world in similar scale to new coal, gas, and hydro systems. Renewable energy now constitutes the majority of new generation capacity installed each year. Electricity from wind and PV systems is now cost-competitive with newly built coal, gas, oil, and nuclear generators in many parts of the world. Roof-mounted PV systems successfully compete with conventional gas and electricity for the supply of heat and electricity in cities. Transport and chemical synthesis powered by PV and wind electricity is likely to be competitive in the future. (Asian Perspect/GIGA)

This paper examines the renewable generation of electricity in Australia from photovoltaics (PV), solar thermal electricity (STE) and wind. PV, STE and wind have immense resources and small environmental impacts even when deployed on very large scales. They are the only fully sustainable technologies able to completely replace fossil and nuclear electricity generation during this century. Wind energy is now a low cost generation technology, and is likely to provide 10 per cent of the world's electricity by 2020. PV has found attractive niche markets and has an annual growth rate of 30 per cent per year. STE is a promising technology but presently lacks niche markets to enable an industry to get started. The Australian Government is offering attractive assistance for renewables, although the lack of research & development funding in these programs is a serious shortcoming.

This paper examines the renewable generation of electricity in Australia from photovoltaics (PV), solar thermal electricity (STE) and wind. PV, STE and wind have immense resources and small environmental impacts even when deployed on very large scales. They are the only fully sustainable technologies able to completely replace fossil and nuclear electricity generation during this century. Wind energy is now a low cost generation technology, and is likely to provide 10 per cent of the world's electricity by 2020. PV has found attractive niche markets and has an annual growth rate of 30 per cent per year. STE is a promising technology but presently lacks niche markets to enable an industry to get started. The Australian Government is offering attractive assistance for renewables, although the lack of research & development funding in these programs is a serious shortcoming.

Silicon solar cells incorporating double-sided pyramidal texture are capable of superior light trapping over cells with front-side only texture. However, increased surface area, roughness and exposed crystal planes of textured surfaces not only causes increased recombination, but also makes cells susceptible to shunting through pinholes in the dielectric at the sharp peaks and valleys of the textured pyramids. A polyimide film as an insulating interlayer film is investigated to circumvent the tradeoff between improved light trapping, increased recombination and increased shunt paths. When applied at the rear of the interdigitated back contact silicon solar cell structure, the polyimide film provides an excellent electrical insulation (> 1000 MΩ of insulation resistance) and increases photocurrent (~ 1.1 mA/cm2) owing to an increased rear internal reflectance. The polyimide is also compatible with metal annealing of passivating dielectrics such as silicon nitride. Optical simulation and experimental results are combined in a 3D semiconductor simulation (Quokka) to quantify the possible gain of implementing the double-sided texture in high efficiency silicon solar cells. ; The funding of this research is supported by the Florida Renewable Energy Efficiency Technologies grant of SO430/24608, and the Australian Solar Institute (now known as Australian Government through the Australian Renewable Energy Agency, ARENA) through research grants of 4-F002 and RND009. This research is partially funded by Trina Solar.

As silicon photovoltaic technology advances, charge carrier losses at the contacted interfaces of the silicon absorber are coming to dominate power conversion efficiency. The so-called passivated contact, which provides selective charge-carrier extraction while simultaneously reducing interface recombination, is thus of significant interest for next-generation silicon solar cells. However, achieving both low recombination and low resistance to charge carrier extraction has proven challenging. Here, we present a passivated contact technology based on polysilicon deposited using low pressure chemical vapour deposition (LPCVD) over an ultra-thin silicon dioxide layer, which achieves an excellent surface passivation with implied open-circuit voltage of 735 mV, a recombination prefactor below 1 fA cm−2 and contact resistivity below 1 mΩ cm2. Key to this technology is the deposition of an ultra-thin silicon dioxide interlayer under high temperature and low pressure condition, performed in-situ within a single process with the polysilicon deposition. Additionally, the passivating contact structure maintains its electronic properties at temperatures of up to 900 °C and is compatible with existing industrial processes. The presented work therefore represents a significant advancement in industrially-applicable passivated contact technology. ; This Program has been supported by the Australian Government through the Australian Renewable Energy Agency (ARENA).