CO2 is Plant Food (Clean Coal, Say WATT?)

Guest Post by Ira Glickstein.

When Lord Monckton told Congress “CO2 is plant food”, the Global Warming activists went crazy because … well, because they know he spoke an inconvenient truth. Monckton’s statement was ridiculed in many blog posts and You Tube videos, but no one directly contradicted his claim because it is clearly correct. Instead, they changed the subject to the supposed effects of rising Carbon Dioxide: too little AND too much precipitation (drought/flood), unusually high AND low temperatures (burn/freeze), and other contradictory consequences.

But, no one can deny the truth. Plants live on CO2. They are made of carbohydrates (carbon, hydrogen, oxygen). They get their carbon from the CO2 in the atmosphere. It is a fact that the best food crop yields occur when plants are grown in atmospheres that are triple or quadruple current CO2 levels. That proves current CO2 levels are way below most of the period of plant life evolution and adaptation on Earth.

This posting is about a concept that unites two technologies I predict will gain prominence in coming decades: Underground Coal Gasification and Elevated CO2 Farming, and how they may be united to provide a sustainable ENERGY and FOOD supply for the coming century.

See Clean Coal (Say WATT?) for an introduction to the concept of clean coal as a critical part of our energy future.

Also download this narrated PowerPoint Show for an animated version of this posting, complete with audio description and more detailed graphics than posted here.

SUSTAINABLE ENERGY AND FOOD CONCEPT

The concept illustrated in the graphic is based on using underground gasified coal (or coal to liquid as an alternative) to generate both electrical POWER and provide CO2 as a plant food in an elevated CO2 greenhouse that produces FOOD as a byproduct, with biomass feedback to generate biogas as additional fuel for power generation.

As indicated, there are three steps to the process:

1. Underground Coal Gasification, Burning the Coalgas to POWER the generation of electricity, and Capture of the resultant CO2 (the plant food).
2. Growing FOOD in an elevated CO2 greenhouse where, using the captured CO2 and the energy of the Sun, yields are greatly improved.
3. Recycling the cellulose and other non-edible biowaste into biogas (methane, etc.) that may be fed back into the fuel supply system for electrical power generation.

WHY COAL?

Coal is currently the most used fuel for generating electrical power in the US, and it is the centerpiece of this concept because it is the most plentiful here and in many other countries. As indicated in the graphic, fossil fuels, namely coal, natural gas, and oil, constitute about 70% of electrical generation in the US. These fuels create CO2 when burned. CO2 has been depicted as a poison, with James Hansen calling coal trains “death trains” and coal-fired electric plants “factories of death”. There are proposals to capture the CO2 and re-sequester it by pumping it into old oil wells, perhaps extracting additional oil by doing so. It seems to me it would be smarter to use the CO2 for the purpose Nature intended, as plant food!

The remaining 30% of US electric generation may be considered “green”. Of that, most is nuclear. We should have done a better job using nuclear, as France did, but we were scared away from it by the dangers of release of radiation and radioactive waste. There is a resurgence of interest in nuclear and we may see more new plants built at some time in the future, but the regulatory environment is daunting.

The “renewable” component of “green” energy makes up about 11.5% of the US total, and consists mostly of water (hydroelectric) with some wind and other sources such as direct solar electric. These pure forms of “green” will probably grow, under the umbrella of government subsidies, but they are unlikely to provide much more than 20% of our electricity for decades, if ever.

MORE DETAIL ON THE SUSTAINABLE ENERGY AND FOOD CONCEPT

The chemistry of the concept is diagrammed in the graphic.

1) Gasified Coal-Fired Power Plant with CO2 Capture

(a) Underground Gasified Coal.

Coalgas (also called synthetic gas or syngas) may be generated within a coal mine. This is done almost completely underground to reduce transport costs and pollution. Safety is improved because there are no personnel required within the mine itself. This technique is especially suitable for very deep mines, where traditional methods would be more expensive, or for low-quality or depleted mines. Newly developed technology makes possible robots that operate in harsh environments as well as remotely-controlled sensors and actuators that permit the highest possible level of control of the gasification process.

Gasification works by first igniting the coal within the coal seam and then pumping in air and water in quantities that are just sufficient to maintain incomplete combustion, such that combustible Hydrogen and Carbon Monoxide are generated. The chemistry is as follows:

6C {carbon from coal} + 2H2O {water} + 2O2 {Oxygen from air} ==> Coalgas: 4H {hydrogen} + 6CO {Carbon Monoxide}

Description of formula: Coal is almost completely carbon. Six Carbon atoms (6C) are combined with two water molecules (2H2O) and two Oxygen molecules (2O2) to produce Coalgas that consists of four hydrogen atoms (4H) and six Carbon Monoxide molecules (6CO).

Coalgas may be further processed to yield liquid from coal, or it may be used directly as fuel in an electrical power plant.

(b) Burning the Coalgas and Capturing the CO2.

The coalgas is piped to the power plant where it is burned to heat the boiler and generate steam to run the generators. Electrical POWER is transmitted to customers via the grid.

The chemistry is as follows:

Coalgas: 4H {Hydrogen} + 6CO {Carbon Monoxide} + 4O2 {Oxygen from air} ==> POWER + 6CO2 {Carbon Dioxide} + 2H2O {Water}

Description of formula: Coalgas, consisting of four Hydrogen atoms (4H) and the six Carbon Monoxide molecules (6CO), when burned in the powerplant, yield POWER to drive generation of electricity plus six Carbon Dioxide molecules (6CO2) and two water molecules (2H2O).

CO2 has been wrongly depicted as a poison. There are projects underway to re-sequester the carbon by pumping it into abandoned oil wells and so on, possibly recovering additional oil in the process. However, since CO2 is plant food, I think it makes far more sense to capture and utilize this valuable product to grow food!

2. Elevated CO2 Greenhouse.

The current concentration of CO2 in the atmosphere is about 390 ppm (parts per million). Doubling or tripling that level in a CO2 greenhouse can greatly increase the yield of many crops. It turns out that 1000 to 1400 ppm is ideal for increasing production of tomatoes, cucumbers and lettuce by from 20% to 50%; grains such as rice, wheat, barley, oats, and rye by from 25% to 64%; roots such as potatoes, yams, and cassava by from 18% to 75%, and legumes such as peas, beans, and soybeans by 28% to 46%! It is likely that genetic engineering could develop new food crops that would thrive in CO2 levels of 2000 ppm or even higher, greatly increasing yields.

CO2 is essential to photosynthesis, the process by which plants use sunlight to produce carbohydrates – the material of which their roots, body, and fruits consist. Increasing CO2 level reduces the time needed by plants to mature. CO2 enters the plant through microscopic pores that are mainly located on the underside of the leaf. This enables plants to combine CO2 and water, with the aid of light energy, to form sugar. Nutrients and water uptake usually increase with higher levels of CO2 and plants develop larger, more extensive root systems that allow them to exploit additional pockets of water and nutrients, and spend less metabolic energy to capture vital nutrients. The chemistry is as follows:

6CO2 {Carbon Dioxide) + 2H2O {water} + 4H2O (added water) + SOLAR ENERGY ==> C6H12O6 (sugar} + 6O2 {Oxygen}

Description of formula: The combustion process produced six Carbon Dioxide molecules (i.e. PLANT FOOD) plus 2 water molecules. To these we add four molecules of water plus the ENERGY from the Sun. This yields FOOD in the form of a sugar molecule as well as six molecules of Oxygen, released into the atmosphere to partially compensate for some of the Oxygen used during the combustion process.

3) Recycling Cellulose to Biogas. Parts of the plant that are inedible, such as cellulose (chemical formula C6H10O6), are biowaste that may be fermented to form biogas, such as methane, which may be pumped back into the combustion process described in step (1).

CONCLUSIONS

The sustainable ENERGY and FOOD concept outlined here has the potential to provide necessary electricity along with foods in the form of vegetables, grains, roots, and legumes in a most efficient manner with minimum release of CO2 to the atmosphere. The concept makes use of coal, which is plentiful in the US and many other countries.

It will be many decades, if ever, before renewable energy sources, such as wind, water, and solar can provide levels of electricity needed for the human population. Nuclear energy, currently around 30% in the US, is probably the best alternative, as France, with over 70%, and other countries have demonstrated. However, despite growing acceptance of nuclear in the US, it remains fraught with regulatory paralysis and “not in my backyard” parochialism.

Clean coal, which even President Obama has said he will defend, is the best answer for the coming several decades at least. There are two aspects to clean coal: (a) Prior to combustion: Reducing release of pollutants onto land or into water or the atmosphere, and (b) After combustion: Capturing and re-sequestering the CO2 and other products of combustion. Underground coal gasification (or the alternative, coal to liquid) is the answer to (a). However, the idea that the answer to (b) should be sequestering CO2 by pumping into old oil wells strikes me as a waste of a valuable plant food resource.

I’m just a systems engineer, but I’m quick on the uptake and have the ability to absorb a little bit about a lot of things – just enough to come up with innovative concepts that may or may not be practical (and, even if practical, are bound to have some sticking points that need lots of detailed study, science, and engineering :^). I love to work with domain experts who know how to dig deep in their area of specialization. I’d appreciate comments on this proposal by WUWT readers who have, I am sure, far more detailed and specific knowledge of the science and technology involved in this concept.