The world is working to make solar energy more efficient so that it can be used today.
What a load of cobblers - solar energy is already viable in India at least, and I suspect in many parts of the developing world.
Myths - Let us first see why we do not think it is viable.
1) Solar cells are expensive to make and really do not make industrial amounts of electricity. From a manufacturing expense and space availability point of view it does make sense to get them into the mid twenty percent conversion rates.
2) Grid power. The attempt right now is to increase solar capture efficiency, thermal efficiency and temporal efficiency to get to a direct comparison versus a coal or gas plant. This is done by using moving mirrors to concentrate sunlight onto capture towers (nice and expensive and using lots of advanced technology) which then can use superheated steam to get more thermal efficiency. Plants that do not work in the night are perceived to need a way to store the electricity so that the high capital cost of these very fancy plants can be defrayed over more hours.
Myths Debunked
In fact solar electricity with usable power and an affordable cost is rickshaw technology that has been around for over a century, and a viable (and still running) solar/gas plant was built in the 80's and 90's with a net efficiency of 11% - that means about 5MW per hectare. Take a look at http://www.luz2.com/apage/12219.php. The poor fellows who started it went bust because of USD 10 per barrel oil and US energy non-policy. They have a new incarnation with much fancier technology that is trying to cut the cost of power generated by 30% by greatly increasing complexity and capital cost.
The question you have to ask yourself is 'why?'
Most power is needed in the daytime so it is OK for a power short country such as India to take what it can get so long as the price per installed KWh (after derating for available hours) is cheaper than any other alternative. With luck wind, gas and our foul weather friend coal will take up the slack. But these do not have to be part of the same package if the damn economics work on a stand alone basis - and they do. Take a bicycle analogy for this one - cheap and cheerful Indian/Chinese bikes are not 20 times less efficient than a set of 2K carbon fibre wheels.
There is no further need for efficiency because the raw material is free (even land in the desert is pretty much free) - so it is a bit like software where Microsoft co-exists with shareware. Even on farmland photosynthesis is only about 5% efficient, and after that you have to process the stuff into ethanol etc. An Indian farmer makes USD 1K per acre net, so to pay him 2.5K to tend 5MWh of solar plantation is cheap - and makes the solar farm cheaper and easier to operate - just move the dishes every hour or so to follow the sun. So cheap and cheerful solar already beats ethanol - and always will.
How cheap and cheerful. All you need is some aluminium, steel, pipes, a heat exchanger and a steam turbine (the last are all available at low cost in India). See http://en.wikipedia.org/wiki/Solar_thermal_collector and http://www.solarenergy.com/info_history.html for a fabulous history of solar power and what might have been had oil not been found.
My guess, based on years of making machines in India is that this set up will cost about 1/3rd of what it does in the US, making cheap solar more money efficient that the latest and greatest in Stirling Engine technology which aims at 30% net conversion efficiency.
What we waiting for Mr. Shinde?
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment