Note: This article was previously posted (in 2008) on RenewableEnergyAccess.com and was found again on sciencedaily.com in case anyone was looking for it.
The Nanomaterials Research Centre at the Massey University’s Nanomaterials Research Centre in Auckland, New Zealand, has developed solar photovoltaic (PV) cell technology that could allow New Zealand to produce electricity from the sun at a ninety percent savings from currently available 2007 silicone PV cells. The researchers at the Centre, led by Dr. Wayne Campbell, have been testing a variety of synthetic colored dyes as a basis for developing dye-sensitive solar cells.
Dye-sensitized Solar Cells
Simple organic compounds, similar to ones that occur in nature are used to make these synthetic dyes. For example a green dye was developed as a synthetic chlorophyll, the natural green pigment that is used by plants make use of sunlight during photosynthesis. Similarly, other tests in the solar PV cells are based on blood hemoglobin, the compound that gives blood its red color. Dr. Campbell, is encouraged by a green PV test demonstration where a 10cm x 10cm area of green cells could generate electricity to operate a small fan in low sunlight conditions, something that currently available (2007) PV cells were unable to do. This could make the green PV cells much better suited for use in cloudy climates.
Environmental Advantages
The synthetic dyes concept could also be applied to tinted windows to capture sunlight and generate electricity. Dr. Campbell, feels that the green PV solar cells would be more friendly to the environment than silicon-based PV cells made from titanium dioxide, a non-toxic mineral found in the black sand in New Zealand. Other consumer products such as cosmetics, paint and toothpaste also use titanium dioxide. However, Dr. Campbell stated that, “the refining of pure silicon, although a very abundant mineral, is energy-hungry and very expensive. And whereas silicon cells need direct sunlight to operate efficiently, these cells will work efficiently in low diffuse light conditions.” Dr. Campbell also pointed out that “the expected cost is one-tenth of the price of a silicon-based solar panel, making them more attractive and accessible to home-owners.”
Possible Commercial Applications
Professor Ashton Partridge, the new director of the Centre stated they currently have the world’s most efficient porphyrin dye, and he hopes to further improve the cell design and efficiency before any commercial development of the PV cells. Professor Partridge confirmed that, “the next step is to take these dyes and incorporate them into roofing materials or wall panels. We have had many expressions of interest from New Zealand companies.” Professor Partridge said the objective of nanotechnology design is to create a much more efficient PV solar cell to maximize sunlight to electricity conversion. Professor Partridge stated that “the energy that reaches earth from sunlight in one hour is more than that used by all human activities in one year,” said Partridge. This promising solar PV cell research represents ten years of funding by the Foundation for Research, Science and Technology.