Professor Andrew Blakers and his colleagues from the Centre for Sustainable Energy Systems at Australia National University have won $2.1 million in Defence Capability and Technology Demonstrator funding to develop very thin, flexible and efficient solar cells for security and defence applications.

“Defence personnel tend to spend a lot of time in the field, so it makes sense that they should tap into the abundant and renewable energy available from the sun. The technology will help defence to reduce its reliance on batteries,” Professor Blakers said.

“This research also has applications beyond defence. The kinds of technology we’re pioneering here could be easily incorporated into consumer devices like iPods or mobile phones and even clothing.” The light-weight transportable solar panels will be a further application of SLIVER cell technology – invented by Professor Blakers and Dr Klaus Webber at ANU – which is currently being commercialised by Origin Energy. These needle-thin photovoltaic cells use much less silicon than traditional cells as a result of a production technique that maximises the surface area of the silicon wafers, meaning that production costs are reduced and power generation efficiencies are increased.

“For a state-of-the-art traditional solar panel you need about 10 kilograms of this expensive hyperpure silicon to generate one kilowatt (kW) of power,” Professor Blakers says. “A SLIVER panel requires less than one kilogram of silicon per kW. In addition, there is a huge saving in wafer processing, because the number of wafers that need to be processed per kW is reduced by up to 60-fold with the SLIVER cell process.”

Origin Energy has invested more than $20 million in the construction of a demonstration plant in Adelaide and has continued to invest in the commercialisation of SLIVER cells.

Crystal clear solar

University of Queensland (UQ) researchers have produced highly efficient miniature crystals which could revolutionise the clean energy industry’s methods of harvesting and using solar energy.

The research team, headed by Professor Max Lu of the UQ’s Australian Institute for Bioengineering and Nanotechnology, is working on a new class of photocatalysts, called titania nano-crystals, which have high visible light activity.

The team has grown the world’s first titanium oxide single crystals with large amounts of highly active surfaces. These surfaces could allow high reactivity and efficiency in devices used for solar energy conversion and hydrogen production, making the harvesting of sunlight more efficient and the resulting energy cost less to produce. It could take from five to ten years before solar energy is converted using the new crystals.

Dux develops all-climate heat pump

Dux Hot Water has released the Airoheat® Subzero, a new heat pump developed for areas that experience colder temperatures.

The new Airoheat Subzero model replaces the previous Airoheat® heat pump model. New features of the heat pump include a de-icing function. The system automatically determines whether ice has developed on the evaporator and commences its de-icing cycle.

As ice lowers the evaporator’s ability to capture heat energy, the Airoheat Subzero system instinctively determines when the de-icing process has concluded and returns to normal heat pump operation, ensuring efficiency is maintained and no heat loss occurs.

This innovation means that the system does not waste the heat previously generated to de-ice, and does not depend on less efficient technology, such as a back-up element, but continuously operates and creates hot water even when mercury levels drop below zero.

The new product maintains the tank heat and uses fans to defrost the evaporator coil, optimising comfort and efficiency in any climate. The enhanced efficiency levels of the system results in two renewable energy certificates points more than the original Airoheat system.

Camouflaged solar panels a success

Dyesol has completed the penultimate stage in its contract with Defence Science and Technology Organisation (DSTO) for the development and demonstration of light weight flexible camouflage solar panels.

In May the Dyesol team successfully demonstrated a panel design to the Australian Department of Defence. The demonstration showed the prototype’s capability to recharge batteries in shady conditions, its ability to produce charging voltage under any light level, to maintain stability over a wide temperature range and to be camouflaged.

Popcorn-ball solar

Using a popcorn-ball design – tiny kernels clumped into much larger porous spheres – researchers at the University of Washington have manipulated light and more than doubled the efficiency of converting solar energy to electricity with dye-sensitized solar cells.

The group made very tiny grains – about 15 nanometers across – then clumped these into larger agglomerations – about 300 nanometers across. The larger balls scatter incoming rays and force the light to travel a longer distance within the solar cell. The balls’ complex internal structure creates a surface area of about 92.9 square meters for each gram of material. This internal surface is coated with a dye that captures the light.

The experiments were performed using zinc oxide, which is less stable chemically than the more commonly used titanium oxide but easier to work with. The overall efficiency was 2.4 per cent using only small particles. With the popcorn-ball design, results presented an efficiency of 6.2 per cent.