If you harvest and store the wood you have permanently captured the carbon. For example there is plenty of wood stored in and around our houses, with room for more. (Well you get the point I hope.)

The problem is where to find the land to grow the trees. The not so obvious answer is to turn deserts into forests. Detractors will ask where will the water come from?

Ok! where there are deserts, there is plenty of solar energy. So use solar energy to pump seawater and use solar energy to distil it. (We have all heard of solar still equipment, and of course a lake or an inland sea serves as solar still to supplement any equipment.)

Detractors will say that solar powered pumps and stills are not developed enough for the application. The answer is to fund that development. (Such items are already commercially available on a small scale.)

Hands up all those folks who would like to see more trees. They are a lot more beautiful than carbon sequestering (industrial) plants. You can actually live in a forest or spend a holiday there. Trees are guaranteed to work more reliably and permanently than Carbon Capture & Sequestration.

And why not spend a lot of money on returning thousands of square miles of desert back into forests. (Sahara, Australia, Gobi, the list is endless and growing.)

Somehow I think the main problem with this approach is that it is not very friendly to the interests of heavy industry and that it raises some very difficult political economy issues.

Now what are we going to do with all that wood and other tree products?. Answer on a postcard to:-

Roy Barton

If you think this makes sense please pass it on and post it elsewhere. The whole subject of climate change certainly needs a bit of common sense applied.

Just in case you wondered, my background is in Nuclear Energy. Nuclear Energy is a solution chucked out by the “Greens” many years ago, and now we are stranded. So I am not very well disposed to that vociferous lot.

(Question… How many of those greens have now changed there tune on nuclear energy?)

In an IGCC plant, coal is gasified and the resulting gas is burned in a gas turbine to directly produce electricity (not steam, as indicated). The exhaust heat from the gas turbine is utilized to produce steam, which is also used to produce electricity. The combined gas turbine/steam turbine configuration is what is known as a “combined cycle”.

Another comment: Enhanced oil recovery will help produce additional domestic supplies from existing producing fields. The incremental oil produced from these fields will replace imported oil – which would be burned anyway. So the net reduction in CO2 emissions is much greater than indicated in your Fig. 3. Many environmentalists agree with this assessment of EOR, and favor it as a way to help jump start and pay for CO2 capture and sequestration.

The cost of CCS that you cite is typically connected with full CO2 capture (i.e. 90%). This is known to be economically impractical and is not necessary. It is generally accepted that burning natural gas in a combined cycle plant is the cleanest form of thermal power generation, with a CO2 emissions level of only about 40% of that associated when burning coal or with coal-based IGCC without CCS.

Therefore, an IGCC plant with 60% carbon capture would emulate a natural gas combined cycle with respect to CO2 emissions.

In fact, 40% capture would emulate a high-efficiency gas turbine plant burning natural gas, which is the current standard applied for new power generation in California and other states with CO2 restrictions already in place (e.g. Washington, Florida).

A CCS level of 40% would greatly reduce the added cost of CCS, and make IGCC with CCS more practical and affordable.

The current re-thinking that is taking place at the DOE with respect to the FutureGen “near zero emissions” IGCC plant is an example where the “40% Solution” would be very well applied. (See http://gasification-igcc.blogspot.com/ )

Harry Jaeger
Gasification Editor
Gas Turbine World Magazine
http://gasification-igcc.blogspot.com/