Home: Renewable Energy News: Monday 25 May, 2009

Renewable Energy News

MONDAY 25 MAY, 2009 |

Sanyo Breaks Solar Cell Efficiency Record

Sanyo HIT solar cell
Sanyo Electric Co., Ltd. (OTC: SANYY) announced on Saturday that the company has broken its own record for crystalline solar cell conversion efficiency in Sanyo's HIT solar panel range.

Sanyo HIT solar panels already had the highest efficiency of any solar panel for the home solar power market. With recent refinements, the company says it has achieved a conversion efficiency of 23.0%; that is, 23% of sunlight hitting the panel cells can be converted to electricity.

This represents the first time that a photovoltaic manufacturer has broken through the 23% mark in conversion efficiency at the research level for practical-sized solar cells.

The Sanyo HIT (Heterojunction with Intrinsic Thin layer) solar panel is constructed of a thin monocrystalline silicon wafer encased in ultra-thin amorphous silicon layers. This hybrid technology allows for excellent performance at high temperatures compared to conventional silicon solar cells.

To gain the additional conversion efficiency improvements, Sanyo refined the HIT solar cell junction through developing a technology for depositing a higher quality a-Si (amorphous silicon) layer over the c-Si (crystalline silicon) substrate while protecting the c-Si surface from being damaged. The company also developed know-how to reduce optical absorption loss in both the a-Si layer and transparent conductive layer.

Additionally, lower-resistance electrode material for use in the grid electrode and a higher-aspect ratio through improving printing technology has led to a success in reduction of resistance loss when an electric current flows through.

Aside from the best conversion efficiency available for solar farms; commercial and residential solar power systems, Sanyo HIT solar panels also offer a smaller footprint, allowing more capacity within a limited area such as a rooftop. The panels offer an added benefit of being a "greener" solar module through the use of less silicon material.

Solar Botanic - Solar Power From Trees

solar power from trees?
Home owners associations in the USA have been known to object to solar panel installations purely on the basis of aesthetics.

The dark monocrystalline solar panels usually aren't so much a problem, but some home owners have faced solar panel snobbery when they have wanted to install polycrystalline panels; specifically those that are blue.

A company called Solar Botanic may have another solution for sensitive home owner associations - artificial trees that make use of renewable energy from the sun and wind. The artificial trees are covered with "nanoleaves"; a combination of nano-photovoltaic, nano-thermovoltaic and nano-piezo generators converting light, heat and wind energy into green electricity.

Solar Botanic claims that in a residential application, the artificial trees will generate 50% more power than conventional solar systems while blending in with the neighbourhood. Depending on size and location, the company says a single tree can produce between 2000 and 12,000 kWh of electricity annually.

On a larger scale, Solar Botanic believes that a kilometre of trees would be able to generate approximately 350,000 kWh per year, enough electricity to power approximately 60 average size houses.

The company uses an example of Highway 1 between Adelaide to Perth, which is 2700 kilometres long. 189,000 solar trees "planted" along the road would generate over 1.2 GW of electricity; reduce our carbon footprint by more than 900 thousand tons of CO2 per year and produce enough electricity to power over 118,000 average size homes.

So where can you buy a Solar Botanics artificial tree? You can't just yet - the company is still looking for potential JV partners who have the required sector expertise and funding to take this project from the R&D phase to full commercialisation.