The article was just a writer being bored and not having any understanding. Thin film at 10% efficiency is fine if you have the roof space. The overall system costs need to be contained as well - the PV panels are only part of it.
I agree with you that reaching 90% efficiency looks like uphill tasks. The technologists and researchers all over world are concentrating their efforts to increase the efficiency and reduce the cost of production of solar cells. Solar cells so far developed are hovering around 18-24 % efficiency. Though customised solar cells developed for space applications show an efficiency of 32%, but they are prohibitively expensive.
With the level of efforts and new technology development going on all over the world, there is no harm in hoping that we may achieve solar cell efficiency of the order of 90%, though it may take some time. Technological and scientific discoveries are full of surprises; we may discover some wonder material that will end the so much talked about energy security and put a full stop to climate change soon.
More than anything else change of mind set is required. Drilling a deep well in offshore costs us around 160 to 170 Million US$. With no guarantee of striking oil or gas. The cost of setting up solar power (PV) generation facility at present market rate is 2.4 Million US$ per mega watt. Drilling a well in offshore set up is equivalent to setting up of a solar power station of 65 Mega watts with assured output for 20 to 25 years. Even if we are willing to invest only 10% of the kind investment that goes into exploration of oil & gas, I am sure that half of the problem of energy security and climate change will be addressed forever and at the same time our over dependence on fossil fuels will decrease tremendously.
For those who care to modify their lifestyle so they consume very little power a few solar panels, a few batteries and some el cheapo charge controllers will provide all the power they need.
This is NOT for the average dummy, but there are a VERY FEW off-grid types doing this today fairly inexpensively.
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