Why does it always have to be either one energy source or another that's going to supply us with all our energy, and that this means the others are all rubbish?
nowt like a load of fact free propaganda, but what do I know, we've only got a couple of MW worth of panels out there, most of which have never been cleaned other than by rain, all bar maybe 0.5% of which continue to perform at or above expectations, that 0.5 are within 5% and the difference was down to error in the shading predictions.
The panels are all guaranteed to still be producing at least 80% of their rated output after 25 years, so they will reduce their efficiency gradually, but will mostly have a useful lifespan of a hell of a lot longer than 25 years - the degradation rate is relatively linear, so most should still be producing at least 60%, probably more like 70% of their rated output after 50 years. No reason at all why well made panels shouldn't have a useful life of a century or more before it really becomes necessary to replace them, albeit that the inverter will have needed replacing 3-4 times in that period. There are certainly panels out there now from the 70s that are still producing around 85% of their rated output.
There are lots of failure modes for PV cells.
http://www.pveducation.org/pvcdrom/modules/degradation-and-failure-modes
Then lets move on to electromigration. This is inherent in all silicon devices, the higher tolerances and level of manufacture the more prevalent a problem this becomes. That will cost you power.
I find it hard to believe the true cost has been factored in to just 4 year? Just making silicon ingots is extremely energy intensive. Silicon chip grade silicon wafers which are essentially 100% pure crystalline silicon are made by melting high grade silicon in a crucible at precisely 5000 C and putting a seed crystal into the molten silicon and lifting and twisting very slowly. Then there are all the cutting and polishing stages with all the chemicals, each of which cost energy to produce.
(Horrible format but to the point)
http://www.solarindustrymag.com/iss...d_In_Silicon_PV_Cell_Production_A_Primer.html
But this is irrelevant to my original point which was about the lack of use of Geothermal.
What bothers me about the lack of Geothermal. If you drill down 10Km it gets very very hot indeed and that hole will pump out lots of energy. Drill 100's of them and you stand to get a huge whack of power. No high technology silicon panels, not reliant on the sun's 50% or less duty cycle, not reliant on the wind, no inputs of any resources to speak of, no waste material, just basic water wheel type energy harnessing. People are less likely to protest about having a plant near their house too.
Those heat maps of the UK are 1-3Km, but why stop there, its not like there is some magic barrier at 3Km? 10Km holes take about 2 years to drill. They are about as deep as man has drilled but might not have to go that deep. Interestingly go much further than 10Km and its all a bit unpredictable as the Russians found out drilling down 12Km.
Once you have dug theses wells, unless they collapse, they are there for good, producing the most eco friendly power I can see, beyond even hydro, for decades. It appears entirely down to lack of will from where I am standing. People talk about renewable energy sources, but I would call it unending. The Earth is by all accounts , 13,000,000,000 years old. Its still molten at the core, so by all accounts its got some cooling down to be doing yet, I doubt the man of today could touch the power held in the centre of this planet.
Srsly.
