Of course, the potential for the use of fish-to-biodiesel for the Tidal Irrigation and Electrical System is huge. The introduction of filter feeding species could lead to a much greater energy capture for the entire system then by the sole utilization of macroscopic algae like kelp.

This does however create the nightmare scenario of giving every marine animal a monetary value as fuel. In the future will there be fishing mafias that strip entire ecosystems? Will the seas be subject to even further unsustainable practices in order to fuel our cars? The oceans already suffer from the tragedy of common ownership. The collapse is imminent in the majority of the world’s fisheries. This technology could inadvertently push them over the edge.

As to the specifics of how the report dealt with the Tidal Irrigation and Electrical System; to put it simply it didn’t. It generalized all systems which utilize deep ocean water (DOW) into one broad category and in that category they only looked at the potential to transport CO2 from the atmosphere to the seabed. This is a great shame because systems which exploit DOW produce power and biomass on large scales. The Tidal Irrigation and Electrical System is the first renewable energy system which has proposed trying to capture the biomass component of the OTEC process. The utilization of these biomass resources can lead to less fossil fuel use and this is because they go into everything from fertilizer to food to plastic to the lights in our city’s and the fuel in our cars. However, this does mean that the biomass generated is not being stored on the sea floor so by the logic of the report it did not do much to offset climate change in that manner.

One idea that the Royal Society is interested in that this author feels desereves special derision is that of “artificial trees”. In proposal, these man made structures would litter our planet by the million. Their sole job is that of absorbing CO2 from the air. They produce nothing and rely on energy intensive processes in their construction and in either the storing of CO2 or the manufacture of the chemicals which are used to absorb the gas. The same problems that face other mechanical or chemical storage methods for capturing atmospheric carbon such as the ones that are proposed for coal burning power stations. A further criticism of artificial trees is that there is only a small economy of scale in the in industrial processes which underpin the concept. None of the designs become more efficient as they grow in scale. It does make this author wonder if it wouldn’t be better to build wind turbines in everyplace they are thinking of constructing one of these things. That might mean that the carbon emitted by the burning of fossil fuels was never released into the atmosphere in the first place.

Recently, I submitted the TIE System for assessment by the Royal Society’s working group on geoengineering schemes to mitigate climate change. (http://royalsociety.org/news.asp?id=8085) In the process I have been looking at a few other ideas. Many of them, like increasing the albedo of marine stratocumulus clouds and shading the earth with a large group of small spacecraft at the inner Lagrange point (L1), totally fail to deal with the issues that simply having more carbon dioxide in the air will create.

Ocean acidification is caused by the upper layers of the ocean taking up CO2 directly and by the changed air currents increasing the weathering of rocks. It seems that previous models have underestimated the sensitivity of the oceans to increased CO2 and acidification can increase much quicker than thought. (http://www.physorg.com/news148227653.html)

This is bad news for these geoengineering schemes that fail to deal with the excess CO2 in the air. One of the most pervasive mass extinctions in the history of the earth was caused, it is thought, by ocean acidification. Massive volcanic releases of CO2 caused the end Permian mass extinction  as acid turned the oceans toxic. (This theory is well explained at http://www.uwm.edu/~mfraiser/pdf’s/Bottjer.et.al.2008.pdf ) Thus the oceans went from a greenhouse gas sink to a greenhouse gas emitter as anaerobic conditions caused wide scale release of methane and Sulfur Dioxide. Global temperature ended up near 35 degrees C. That is rather eye watering considering that 2007 had a global temperature of 15.04 degrees C.

Already a fifth of the world’s coral reefs have died and we could lose most of those remaining in the next 20 to 40 years according to the Global Coral Reef Monitoring Network. (http://www.physorg.com/news148116950.html) This is due to temperature rise and acidification and will destroy the livelihoods of an estimated half a billion people who depend on coral reefs, unfortunately this may be only the beginning.

It seems the list of side effects due to our use of fossil fuels grows longer by the day. We must bring our carbon use into balance or who knows, we may wind up at the end of the Permian again. 

By the late 18th century, minds were already turning to the problems of too many mouths to feed given the agricultural technology of the time. Malthusian predictions of population crash and civil disorder due to our inability to produce food faster than our population grows have emerged with a fair degree of regularity ever since. We have developed new strains of crops and this plays a part in meeting our need for food, but this is tiny compared to the new technologies that supply water and nutrients to the plants and those that transport the food to the populace at large before it rots.  Thankfully the final components in plant growth i.e. sun light, appropriate temperature fluctuation and atmospheric composition, have never been an issue for modern humanity to face. The technological developments have been varied: some simple, like crop rotation and the mining and applying to the land of ancient deposits of bat guano, and some industrial, like freezing, pumping, mechanization and chemical fertilizer.  

Despite the advances of plant breeding and the development of genetic modification, the reality is that increasingly, we have relied on techniques which are energy intensive to produce the food on which all live – and energy generally means fossil fuels. There is a wonderful letter in the New Scientist that illustrates the problem:

Peak soil 25 June 2008

John Chambers, Banbury, Oxfordshire, UK

William Stanton observed that, as oil is needed to work the farm machinery and natural gas is needed to produce the synthetic fertiliser used in grain production, the phenomena of “peak oil” and “peak gas” will inevitably lead to “peak grain” (31 May, p 23). The amounts of energy involved are indeed huge: it takes at least 35 megajoules to produce each kilogram of nitrogen in synthetic fertilisers, and 80 million tonnes of such fertiliser is used globally each year.

There are, however, yet more risks to grain production: 70 per cent of the world’s water use is in the irrigation of arable land. About 1000 tonnes of water is required to produce 1 tonne of grain. Much of this is drawn from underground aquifers – and these are close to depletion in parts of central Asia, the Middle East, north Africa, India, Pakistan and the US. Drill holes in excess of 1 kilometre deep are not uncommon, but to lift 1000 tonnes of water over that distance requires at least 9.8 gigajoules.

Grain is grown in soil, but 65 per cent of all soil on Earth shows signs of degradation such as erosion, desertification or salinisation. Over 300 million hectares of former agricultural land is now too degraded to produce food, and a further 10 million hectares become degraded or damaged every year.

“Peak soil” is long gone.

From issue 2662 of New Scientist magazine, 25 June 2008, page 24.

Biofuels grown on the land are not the solution. When factoring in the total energy that we consume in the agricultural process, biofuels generally fail to be worth the effort; you lose more energy than create and of course the water problem can only partially be fixed by pouring more energy into extracting it from the ocean or the ground. Even the use of the waste from crops for biofuels should be carefully considered before large scale implementation. The issue is about the nutrients that are represented by the waste being taken away from the soil. Traditionally crop waste is left to rot or to be eaten by animals which break down the plants for return to the soil and use by the following crop. As it is, this system is liable to exhaust the soil eventually. The nutrients that are locked up in the food we consume are removed and not returned to the land. Biofuels using crop waste will only exacerbate the problem by removing the nutrients represented in the form of stalks and leaves for use as fuel. 

The only solution is to find a new way to generate fertilizer. The Tidal Irrigation and Electrical System can do this by bringing deep ocean water (DOW) into its lagoon. The water in the deep ocean contains the vast majority of decomposed bodies of all the things that ever lived on the land or in the sea. It is the perfect medium for plant growth, and were it not for the salt we could spray it directly onto our crop lands and expect phenomenal growth. Kelp makes an excellent fertilizer and has been used for many centuries and grows, like all marine plants, extremely quickly in the presence of DOW. (See Algae/Marine Plants) 

There is a wonderful example of a natural process which moves DOW from the ocean to high up into the mountains where it fertilizes an entire forest ecosystem. Certain ocean currents and winter brings DOW to the surface in the pacific northwest and consequently marine plants bloom and these plants go on to feed the animals. Salmon sit near the top of the food chain in that part of the ocean and as such each one of them represents a large concentration of nutrients like iron and nitrogen. As they move up the rivers into the mountains to spawn they are heavily preyed and scavenged upon. The eagles, bears and vultures move on to their respective wider territories which extend for hundreds of square miles beyond the river. There they spread manure (which is fertilizer) far and wide. Eventually they die and their bodies are scavenged spreading the nutrients even farther across the Rockies. 

The TIE System can create the source material for fertilizer on a vast industrial scale as well as help alleviate some of the fresh water problems we are facing. A product of the OTEC subsystem is thousands of gallons of fresh water. Pipes made cold by DOW condense water out of the atmosphere when exposed to tropical air. The TIE System does all this without aggravating the problems of land-based agriculture. 

Also, studies of Coal Oil Point conducted by Susan Mau at the University of California at Santa Barbara indicate that only one percent of the methane released into the ocean makes it into the atmosphere. Coal Oil Point, a huge and well studied natural methane seep on the bottom of the sea off the coast of Santa Barbara, releases about two million cubic feet of methane a day. By using data from 79 surface stations, they studied the plume of released gas in an area that covered 280 square kilometers. Full results will be published as the cover story in Volume 34 of Geophysical Research Letters.

David Valentine, associate professor of Earth Science at UC Santa Barbara, hypothesized that the methane is oxidized by microbial activity in the ocean. Although there was no attempt to capture or culture said microbes, there is little other explanation for the destruction of the methane. 

Microbial agents will be vital for minimizing the generation of methane due to the increased biological activity as DOW is brought to the surface by the Tidal Irrigation and Electrical System. The research above shows just how effective these microbes can be.

The New Scientist reports in its June 12th 2008 issue that it now seems the UN Convention on Biological Diversity also has deep concerns about the process and has banned it until more research has been done. At the same time Mary Silver of the University of California, Santa Cruz has presented her findings to the American Geophysical Union in Fort Lauderdale, Florida. She has results that indicate that iron encourages the growth of particular algal populations that produce domoic acid – a potent neurotoxin. Domoic acid can sicken or kill animals and people who eat contaminated shellfish.

Hopefully this will encourage those who see the potential in marine algal growth schemes to look more closely at the full life cycle of what they produce and to instead consider the TIE System. The TIE System uses DOW, which is the ideal fertilizer for algae, and it contains the biomass so the open ocean isn’t shocked and methane pollution can be limited.