Is solar panel cost effective?

I hold the view that photovoltaic panels are not cost effective at this moment (solar energy to electric energy conversion efficiency is only up to 20%; to power a TV, you need over 1 sqm of panels and one 175W panel costs A$1925, see: http://www.solazone.com.au/PVpanels.htm ).

Now go to that link and look at some real numbers!

175W panel cost A$1925.

Now, look at the tariff rates here:
http://www.energy.com.au/energy/ ... _July_07_EA_Res.pdf

Now, if I assume the most expensive rates of : 27.61 cents/kWh

The solar panel needs to generate : $1925 / 0.2761 kWh of electricity to pay for itself. This is 6972 kWh.

For this panel to gnerate 6972 kWh of electricty, it takes 6972 / 0.175 = 39840 hours of full capacity generation.

If I have an average of 9 hours of sunshine each day, it takes 4426 days or 12.1 years of continuous full sunshine everyday.

So unless you are really keen to "show" your committment to ESD, solar panels (photovoltaic panels) are not cost effective if you already have connection to the power grid.

P.S. The story would be somehow different with remote areas where generators or power lines are required to supply electricty. By that time, the comparison will be the installation and running costs of generators and power lines. PV panels will be attractive for those applications.