I caught the tail end of a special report from PBS on Global Warming, hosted by Alanis Morrisette. Now, I’m all for caring for our environment and cleaner technology; but the portion I saw dealt with building these enormous CO2 absorbing “synthetic trees.” The idea is that these massive structures, over 1,000 feet high, would be soaked in compounds which would capture CO2 and convert it into a solid, not unlike the material used by many sea creatures like coral.
According to preliminary research, these “synthetic trees” would sequester and convert approximately 90,000 tons of carbon dioxide and produce 3 megawatts of electricity: “With a footprint as huge as a football field, this tree will not only capture carbon, but also generate power. The idea is to develop a process to arrest and store carbon dioxide, similar to the process of Photosynthesis.” (http://www.ecofriend.org/entry/synthetic-trees-to-capture-carbon-dioxide-and-save-the-planet/)
Here is the thing that bothers me…HOW would we construct these 1,000 foot high structures? Each would require the massive construction of a skyscraper. Keep in mind that we’re not talking about one or two of these things, but thousands, possibly even tens of thousands of them. In fact, the architect behind the idea proposes that we construct 250,000 of them across the globe. (http://discovermagazine.com/2005/oct/climate)They would be scattered about the continents and oceans, covering enormous portions of the landscape.
Now, 250,000 of these monstrosities would in theory clear 2.25 X 1010 tons of carbon from the atmosphere every year. The current figure for the amount of carbon in the atmosphere is 3.0 X 103 gigatonnes, which is approximately 3.3 X 1012 tons. According to these figures, once the synthetic trees were constructed, we could be back to pre-Industrial Revolution levels within five years; and the atmosphere would be entirely carbon free in less than 150 years. There’s only one problem with that. Every plant on earth would die because they require CO2 to exist.
Ok, so if we build a single massive synthetic tree, we have to expel into the environment the carbon required to construct a skyscraper; but fortunately, we will suck some carbon out of the air. We also have to manufacture sodium hydroxide, the compound the synthetic trees would need to be saturated in so they could suck the carbon out of the air. Besides being an extremely caustic substance, sodium hydroxide can kill you if consumed. Oh, and we’ll kill all the trees.
I have an alternative proposal…plant real trees!
The average tree – just your plain old, run of the mill normal tree – will sequester 50 pounds of CO2 per year. Even better, according to some studies I read here, tropical trees like pines and eucalyptus can sequester up to 10 tons of carbon per hectare per year. A hectare is 10,000 square meters – approximately 2.5 acres. That means that every 10 acres of forest could clear 40 tons of carbon per year.
There are 640 acres in a square mile, which means that every square mile of forest that we plant would clear 2,560 tons of carbon from the atmosphere. Thirty-five square miles of forest would do the same thing as a single “synthetic tree” without using hazardous chemicals and with no construction costs except planting trees.
Thirty-five square miles sounds like an enormous stretch of land, doesn’t it? But it’s not. The White Mountains National Forest is wholly contained within New Hampshire, the 6th smallest state in the union, and it covers 1,171 square miles. That’s right – the White Mountains National Forest is the equivalent of 33 of these synthetic trees. This is land that was clear cut only a century ago.
Why not irrigate the land where we would build these synthetic trees, and then plant forests? We have enormous tracts of unused land just in the United States. According to most estimates, CO2 levels are 35% higher than before the Industrial Revolution. That means, we need to reduce carbon by 1.16 X 1012 tons. Let’s say we plan to do this over a century by planting forests. Let’s say we plant five square miles of forest every year and it takes 20 years for each planting to reach maturity. In year 20, we would reduce atmospheric carbon by 1.25 X 104 tons. By year 50, we would be reducing the carbon in the atmosphere by 5.81 X 106 tons per year and would have already pulled 6.2 X 107 tons. The new forests would cover only 250 square miles, an area only slightly larger than 2% of the White Mountains National Forest.
I could continue with the endless calculations, but you get the point. The answer is not new technology; it is God’s technology. If you want to balance carbon, then use the things God created to use carbon and keep the balance of the planet. PLANT TREES.