Artificial trees

Where was this?

I am not quite sure what you are asking about. For thousands of years we have been and still are utilizing natural photosynthesis to meet our nutritional requirements which is by farming.

What are artificial trees? Do you mean the ones grown in nurseries or things which act like trees but are not alive? And what kind results you are talking about?

 

In perspective: (roughly)
1 square mile = 5280x5280 = 27,878,400 square feet
If a tree needs 10 square feet to survive then there are: ( density of forest assumed )
2,787,840 trees in a square mile
Half a billion trees would need then approxiametely
200 square miles ( or 10 miles x 20 miles ) ( 0.075% of all of Texas )
In each square mile there are 640 acres so,
128,000 acres ( Just about a Sam Houston Nat Park size area )

Sam Houston National Park is 161,508 acres in size.

Texas itself is 268,581 sq mi
How much is actual forest area =??

Wildfires have burned more than 3 million acres in Texas since the fire season started
http://amarillo.com/news/latest-news/2011-06-20/texas-wildfires-burn-3-million-acres
but grassland and forest included in this figure I would surmise.

 

We very often have natural forest fires across Alaska that burn hundreds of thousands of acres of trees.

The Role of Natural Fires:
http://alaska.fws.gov/nwr/yukonflats/fire.htm [Broken]

 

Research is in progress on Artificial Photosynthesis as a renewable source of energy. However the technology is far from being practical.

http://en.wikipedia.org/wiki/Artificial_photosynthesis

As for the link you provided, things like that would not really solve the issue. While they would solve one problem, they'll bring with them three more. The cheapest and most effective idea would be to conserve whatever natural forestland we have.

 

As has been pointed out artificial photosynthesis is a working research goal however I fail to see why large scale deployment would be more desirable than investing in dealing with draught conditions and mass planting of seeds at the best opportunity.

 

That is one bad idea.

First, the numbers don't add up. Worldwide production of sodium hydroxide is about 60 megatons (wikipedia, so take that with a grain of salt, pun intended). Converting every single bit of that 60 megatons of sodium hydroxide to sodium carbonate would sequester 33 megatons of carbon dioxide. Worldwide human production of carbon dioxide is about 35 gigatons (Gerlach, T. (2011), Volcanic versus anthropogenic carbon dioxide, Eos Trans. AGU, 92(24), 201–202, doi:10.1029/2011EO240001).

So, right off the bat there's a bit of a problem here. We need more sodium hydroxide. Lots more. 1000 times more.

Another problem: It takes a good deal of electricity to produce sodium hydroxide. Producing this electricity will create carbon dioxide. Energy is also needed to move the sodium hydroxide from the production site to the artificial tree farms, to pump the sodium hydroxide solution up the trees, and to pump the sodium carbonate solution down into the ground. All this energy consumption detracts from the sequestration. Yet another problem: Producing sodium hydroxide creates chlorine gas. Lots of chlorine gas. The process typically used to create sodium hydroxide is the same as the one that is typically used to create chlorine gas. What is to be done with that 1000 times excess amount of chlorine gas produced for this sequestration process?

One final problem: Another name for sodium hydroxide is caustic lye. It's a Class 8 HazMat material. Intentionally making a mist of a sodium hydroxide solution and circulating it with air is one heck of a bad idea. Any animal living downwind of that artificial tree farm would soon become an ex-living animal.

 

But what about carbohydrate since that is also part of photosynthesis? I mean would it be edible? What taste it would have? Would it be more like a potato or apple or banana or something else?

 

The carbohydrate doesn't have to be edible to human beings to be useful.
1) It could be combustible fuel, so that the carbon is recycled..
a) One may be able to use it for gasoline, heat or electricity.
2) It could be a source of organic materials.
a) For chemicals, plastic, asphalt-substitutes, wood-substitutes, medicine or other places where now we use petroleum.
3) It could be food for heterotrophic organisms like animals, protozoa, fungi or bacteria.
a) The heterotrophic organisms could be food, fuel or chemicals.

The argument for nonbiological photosynthesis is that it may be faster and more efficient that biological photosynthesis. Plants aren't very efficient with regards to energy. Biological photosynthesis is very far from being a reversible heat engine. Hypothetically, an artificial "tree" can be built that stores almost all the energy incident as sunlight in carbohydrates. However, there are many obvious drawbacks as well as a few we can't imagine just yet.
I am not for this direction of technology. There will be probably be many drawbacks to nonbiological photosynthesis, even if we can make it more efficient in terms of energy. However, in case of ecological disaster there is still another use the carbohydrates.

3b) Copious amounts of liquor for everybody!

 

Well yeah but let's say we're talking about colonists on Mars they could surely use the carbohydrates if they could make it by artificial photosynthesis.