Artificial Photosynthesis...

GopherT

Joined Nov 23, 2012
8,009
I'm sure that @GopherT and @jpanhalt will enjoy this article.

I rank artificial photosynthesis just a few steps below the importance of achieving nuclear fusion.
It is a cool topic and researched to death. If reasonable economic efficiency is ever attained, then you get 24-hour energy source from the sun. Not exactly synthetic photosynthesis but I think intermediate solutions like growing oil producing blue-green algae farms by using the exhaust of a coal-fired power plant is rather brilliant. The goal there can be energy or it can be gene-spliced algae making chemical raw materials.
 

nsaspook

Joined Aug 27, 2009
13,086
Here's another interesting article dealing with a similar subject.
That looks promising if they can get the efficiency into double digits but as usually the devil is in the details.
"It takes energy to make the PV cells, it takes energy to build the fermentor to grow the bacteria, it takes energy to grow the bacteria a lot, it takes energy to purify the fuel, it takes nutrients like nitrogen and phosphate to feed the bacteria, " he said. "It's not that I don't believe. It's that damn math thing. It just never works out."
 

wayneh

Joined Sep 9, 2010
17,496
Meh. It's still limited by sunlight, with all the problems that entails. (Night, clouds, season, etc.) Silicon PV panels are at 20% and pushing 30% or more. Meanwhile, evolution has announced a high reward for photosynthetic efficiency and a few species have stepped up to claim the prize. Switch grass, for instance: "Estimated mean NEY on established switchgrass fields was 60 GJ·ha−1·y−1". I don't have the gumption to convert that to watts per m^2 to compare to PV panels, but I bet it's not terribly exciting.

Assuming you can beat evolution sets a high bar for your work.
 

GopherT

Joined Nov 23, 2012
8,009
Let's see, 1.5 mTons of steel (iron),
- mined iron ore,
- transported to the mill
- smelted
- cast
- moved to location for final fabrication
- moved to tower location
- (Crane transported to tower location)
- lift 2 x 750 kg turbines into place

All for 10,000 kWh PER YEAR = 1.14 kWh per HOUR which is about 30 standard fluorescent tubes at 40 watts each.
Which cost about $0.25/kWH in France. That is a savings of $2500/year!

Assuming a zero interest rate and an approximate price of this project at a meager $250,000, the economic payback is 100 years.

Wait, one article says I am not supposed to think of the money. Ok, then lets look at the energy it takes to do all the steps listed above and check how long the energy payback is. I sent an email to the press contact at UGE International to ask that very question. To my surprise, I got an immediate answer, "you are not supposed to look at a project like this in that way." She went on that this is an awareness campaign for micro wind turbines blah, blah, blah. I wondered for a while and asked myself, which micro wind turbines would be profitable if not at the Eiffel Tower. Then I realized, they are all profitable ... For UGE International.
 

Thread Starter

cmartinez

Joined Jan 17, 2007
8,220
Let's see, 1.5 mTons of steel (iron),
- mined iron ore,
- transported to the mill
- smelted
- cast
- moved to location for final fabrication
- moved to tower location
- (Crane transported to tower location)
- lift 2 x 750 kg turbines into place

All for 10,000 kWh PER YEAR = 1.14 kWh per HOUR which is about 30 standard fluorescent tubes at 40 watts each.
Which cost about $0.25/kWH in France. That is a savings of $2500/year!

Assuming a zero interest rate and an approximate price of this project at a meager $250,000, the economic payback is 100 years.

Wait, one article says I am not supposed to think of the money. Ok, then lets look at the energy it takes to do all the steps listed above and check how long the energy payback is. I sent an email to the press contact at UGE International to ask that very question. To my surprise, I got an immediate answer, "you are not supposed to look at a project like this in that way." She went on that this is an awareness campaign for micro wind turbines blah, blah, blah. I wonder which micro wind turbines would be profitable. Then I realized, they are all profitable ... For UGE International.
You just proved my point... from a different angle...
 

GopherT

Joined Nov 23, 2012
8,009
It is likely better to think of that project as paying back in 100 years for every $250,000 in cost. I would bet the price tag is closer to $5M than $250k
 

GopherT

Joined Nov 23, 2012
8,009
Ok, found it.

The cost of the €30m upgrade is being met by the Société d'Exploitation de la Tour Eiffel, the commercial company which operates the tower. It marks the first major renovation project for the tower in 30 years.
Appears to include a thermal solar system that heats water for the two pavilions below the tower.

Assuming they save another $2500/year on hot water, the upgrade has a payback of...:eek:
 

Thread Starter

cmartinez

Joined Jan 17, 2007
8,220
Ok, found it.



Appears to include a thermal solar system that heats water for the two pavilions below the tower.

Assuming they save another $2500/year on hot water, the upgrade has a payback of...:eek:
€30m = $33 USD.... that's a lot more than what I have in my retirement savings account...
 

wayneh

Joined Sep 9, 2010
17,496
They've placed a couple of wind turbines at the Eiffel Tower... I see it as more of a political statement than a real energy contribution... but whatever.
It's absolutely all about making a statement. Just consider the location. It is therefore very ironic that the turbines "...are painted in the same color to minimize their visual impact on the 126-year-old tower". Why minimize the visual impact of a statement?! They should have painted it fluorescent pink.

I could have minimized the impact for free, by choosing another location. And then not installing it there either.
 

GopherT

Joined Nov 23, 2012
8,009
It's absolutely all about making a statement. Just consider the location. It is therefore very ironic that the turbines "...are painted in the same color to minimize their visual impact on the 126-year-old tower". Why minimize the visual impact of a statement?! They should have painted it fluorescent pink.

I could have minimized the impact for free, by choosing another location. And then not installing it there either.
From,
http://www.telegraph.co.uk/technology/news/11434117/Eiffel-Tower-fitted-with-two-wind-turbines.html
said Nick Blitterswyk, chief executive of UGE. "When visitors from around the world see the wind turbines, we get one step closer to a world powered by clean and reliable renewable energy."
 
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