AQUATER PAPER 2.4-ENERGY, WATER, FOOD AND THE AQUATER OCEAN TRADE NETWORK

THE PROBLEM

The world’s fresh water use is nearing the total available. Similarly, the world’s food use is nearing the total available. Finally, the world’s fuel use is nearing the total available and is also causing global warming by producing carbon dioxide-a greenhouse gas. But the world’s population is still growing. Clearly, this is a disastrous situation in the long term. In a companion paper (see ap5 DIMINISHING WATER AND FOOD SUPPLIES – July, this site), a need is described for a means to gradually replace 10% to 20% of the world’s unsustainable land based food and water usage with sustainable supplies to allow for the existing world food and water systems to be converted into a sustainable configuration. The paper ap5 also notes that our agricultural system depends on using methane conversion into ammonia for nitrogen fertilizer with a by-product of carbon dioxide-a greenhouse gas. Clearly this system is undesirable and unsustainable and must be replaced. In another companion paper (see ap2 ENERGY SCARCITY AND NEW OPTIONS -Jan, this site), a need is described for a gradual replacement of the use of the world’s fossil liquid fuels with “green” liquid fuels i.e. fuels that are obtained by recycling atmospheric carbon dioxide into liquid biofuel. In ap2, the SEMAN, a vessel that harvests energy from the oceans, is proposed for this job. Let us look at this long-term problem in a little more depth to determine what can be done to produce a practical ocean trade network from these SEMAN to provide these products in a “green” way and thus avert this potential ecological disaster. 

 

THE SOLUTION

Aquater2050 LLC is working on a program to place ocean-based vessels (SEMAN) that carry wind turbines, wave generators and solar cells in the high-energy areas (wind speed >15kn) of the oceans (see ap2).  These SEMAN would generate 100 to 400KW in electrical energy. In addition, the SEMAN will desalinate water and grow food for the occupants and for sale. Each SEMAN will make at least $55,200/yr (see below). In addition; the world has a current need for jobs (see ap3). SEMAN are relatively inexpensive ($100,000 for materials, and an equal amount for labor-about the price of a small house). So we may expect that many vessels will be built and launched. Thus it is expected that these vessels will be built and sent to sea rapidly as soon as the prototype is finished and tested.

 

There is a limit to the number of SEMAN that can be placed on the oceans. It is important to estimate this limit to find out if the SEMAN can satisfy the world’s need for energy, food, water and jobs. Each SEMAN in a pod requires a certain amount of space to provide safety and eliminate energy harvesting interference. Also, each SEMAN in a pod should remain within line-of-sight communication distance (about 20NMI depending on the height of the transmitter antenna) of a central communication and governing SEMAN to allow use of UHF communication equipment or (less certainly) visible signaling devices. This gives an area of about 1260sq NMI. Such an area would define the number in a pod as follows. One-third nautical mile spacing (0.34sq NMI operating area) should give collision avoidance safety and minimize energy harvest interference for the SEMAN design currently under construction. This would allow about 6300 SEMAN (25200 people) to operate in a pod. As an example, if each pod were separated by about 20NMI to give a pod safe maneuvering space while moving as a group, 200 million SEMAN would require about 50 million sq NMI to operate. An initial estimate from satellite wind data indicates that winds with a mean velocity of 14 to 22 KN accompanying waves of 4.5 to 9 feet would normally cover about 40 to 70 million sq NMI depending on the month of the year (mostly south of the equator in June, north in December, and roughly equally divided otherwise). Thus the earth should be able to support about 200 million SEMAN of the design currently under development. Obviously this definition of a pod’s characteristics is only a rough estimate that must be refined as SEMAN pods begin to form and gain operational experience, but it will serve as a benchmark design for the purposes of these Aquater Papers.

 

Producing Food and Desalinized Water

The SEMAN offers a means for the growth of the food and fuel supply as follows.

  • A top deck area divided into open trays exposed to sunlight of 50 by 20 ft or 1000 sq ft. is suitable to plants.
  • A below deck area in 4 layers divided into covered trays exposed to artificial light of 6 by 50 ft or 1200 sq ft is suitable to plants.
  • A lower hull area in 2 layers of 6 by 50 ft or 600 sq ft. is suitable to aquaculture.

Example food plants well suited to these growth areas are:

  • Grains-wheat and rice.
  • Tubers-potatoes.
  • Vegetables-carrots, lettuce, tomatoes, Brussels sprouts etc.
  • Fruits-strawberries, cantaloupes etc.

Example aquaculture products suited to the lower hull area is:

  • Shellfish-mussels, clams and shrimp
  • Fish-Tilapia

 

The food output of a SEMAN can be used to feed the owners, and then the remainder can be sold on the world market. The output can be estimated as follows. Hydroponics equipment can grow edible plants with roughly the following efficiency.

  • Wheat-0.0067 lb/sq ft da
  • Potatoes-0.028 lbs/sq ft da
  • Mixed vegetables-0.156 lbs/sq ft da

The energy value of the above foods is roughly as follows.

  • Wheat-1200 kcal/lb
  • Potatoes-200 kcal/lb
  • Mixed vegetables-75 kcal/lb

Excess grain can be used to feed chickens to provide protein in the form of eggs and poultry. The efficiency of production of this protein (kcal of protein/kcal of feed grain) is:

  • Eggs-18%
  • Poultry-11%

Aquaponics can also be used by SEMAN to provide both plants (lettuce, tomatoes and cantaloupe) and aquatic animals (tilapia, crayfish, prawns and bivalves) as an output food source for SEMAN owners and for sale.  Aquaponics is a symbiotic system in which toxic effluents from aquaculture (ammonia) are led to the hydroponic system where these by-products are broken down by nitrogen fixing bacteria and then filtered out by plants as nutrients. After this, the clean water is recirculated back to the aquatic animals. Normally, the stock feed for the aquatic animals is fishmeal, but this is impractical for SEMAN. Furthermore, this practice is putting a serious stress on the fish types used to produce the fishmeal. A promising alternative is growing duckweed or a similar food plant in a portion of the hydroponics system for use as fish food. Other procedures are under development, but these appear the most promising for the SEMAN.

 

Humans need roughly the following amount of energy.

  • Adult male-3000 kcal/da
  • Adult female-2200 kcal/da
  • Child-1000 kcal/da

Thus, the world food output to cover its population, using an average consumption of 3000 kcal/person/da and a total world population of 7 billion, is 2.1-exp13 kcal/da.

 

Let us now establish what food outputs can be obtained from a SEMAN system. If the top deck is used to grow wheat, the following output results.

  • 6.7 lb/da or 8040 kcal/da-enough to supply two adults and two children, plus 840 kcal/da for chicken feed.
  • 20 lb/da of non-edible parts-ie. Stems and leaves consisting mostly of cellulose

Also, the 1200 sq ft of below deck growing area can supply roughly 8040 kcal/da of wheat or other food crops such as potatoes and mixed vegetables. This output can be augmented by Aquaponics to provide fish and shellfish as described above. We see, then that 200 lb/mo of food can be sold on the world market for a value of ~$400 and a volume of ~20cu ft. Note, however, that ~5KW of electrical power will be required for domestic use, 0.3KW will be required to desalinate 50gal/da of domestic water,  ~20W of artificial lighting power for each of the 150 lighted hydroponics trays (3KW) and 1.2KW to desalinate 250gal/da of hydroponics water. Thus a total of 6.5KW is required. We see, then that from 200 million SEMAN ~1.6 exp12 kcal/da can be added to the world food supply to gradually replace the non-sustainable part with sustainable food supplies. This is clearly a significant contribution (~8 % of the requirement) to the world food supply, and can provide the beginning of a gradual replacement of the unsustainable portion of the world food requirement with a sustainable system so the land resources can be reformed into a sustainable mode. 

In addition to this contribution to the world food supply, SEMAN energy can be used in reverse osmosis equipment to supply clean drinking water to augment the world’s supply. The clean drinking water requirement is about 1.0 gal/person/da, which makes a total usage for 7 billion people of 7 billion gal/da, or 35 gal/da (1050 gal/mo or 140cu ft/mo) for each SEMAN. This may appear to be an excessively large volume of SEMAN storage to use for this product, but since it is needed for hydroponics, the SEMAN gets double duty from the space. This would require ~0.15KW of electrical power to desalinate the seawater. This water may yield perhaps $100/mo revenue (~$0.1/gal) for each SEMAN. This volume of water from 200 million SEMAN could also supply all of the safe drinking water needed for humans in the world, and perhaps 10% of the total fresh water usage for humans excluding farming and industrial usage.

 

Producing Liquid Fuels                                          

The non-edible plant refuse (~20 lb/da) from the top deck can be turned into crude oil by one of several Biofuels processes currently under development which use a solid biomass feedstock. The one of greatest interest uses pyrolysis to produce a bio-oil, which is then catalytically stabilized and deoxygenated to produce a jet-type fuel. An example Biomass to Liquids (BTL) demonstration plant that produces 300 barrels of Fischer Tropsch fuels per day is operated by Choren Industries in Freiberg, Germany.  The result for each SEMAN is ~15 lb/da of crude oil roughly equivalent to diesel fuel. The value of the oil stock is roughly $0.25/lb ($100/bbl). Thus, the value of the oil produced is $3.75/da or $112/mo. A roughly equal amount of oil stock can be made from the non edible parts of the output of the 1200 sq ft in the below deck area (a somewhat smaller output per unit area because it will grow less efficient potatoes, fish food and mixed vegetables). Thus the total income from this 30lbs/da (900lbs/mo or 125 gal/mo) of Biofuels is about $224/mo for each SEMAN. So, the total oil producible by 200 million SEMAN is ~3 exp9 lbs/da or ~7.8 exp6 bbl/da. This is a significant income boost to SEMAN owner income, and it can obviously replace the current fossil crude oil world consumption of 8.5 exp4 bbl/da with “green” fuel plus any increase in consumption expected in the near future (up to 2050) plus begin to replace base load energy currently covered by coal fired plants. Note that ~20 KW of SEMAN electric power will be required to operate the BTL equipment. Any residual carbon based waste from this process can be packaged and sunk to the ocean floor. Thus this fuel does not contribute to Global Warming. Although this BTL process equipment is in the demonstration phase as noted above, some development will be required to adapt it to SEMAN use.

 

Sequestering Carbon Dioxide

The carbon dioxide generated by man is 2.4 million lb/sec, so 690 million KW is required to freeze this carbon dioxide and send it to the bottom of the ocean. Now 200 million SEMAN can operate on the oceans of the world and make a profit, so each would need to provide 3.5 KW of its power to sequester all the carbon dioxide generated by man (see ap 11 CLIMATE AND WEATHER CONTROL-June, this site). The output is dropped overboard and doesn’t have to be stored. This capability of sequestering carbon dioxide can be sold on the land to electric utilities and other carbon dioxide emitters through carbon exchanges for roughly the $0.08/kwh energy required, or $216/mo. These carbon exchanges are currently being set up in California. The resultant carbon dioxide does not have to be stored or transported since it will be dropped overboard and sunk.

 

Producing Nitrogen Fertilizer

Finally, the SEMAN can produce nitrogen fertilizer concentrate (nitric acid) with the remainder of its energy. The nitric acid is converted into ammonium nitrate or NPK, for example, and used to make fertilizer with 20% nitrogen content and 80% other materials. Assume the Pauling process (a fan shaped electric arc that “burns” the nitrogen with the oxygen in air to make nitric oxide, which becomes nitric acid when dissolved in water) is used to obtain nitric acid. This acid can then be used to dissolve phosphate rock to produce a mixture of phosphoric acid and calcium nitrate. The result can then be combined with potassium chloride to produce a fertilizer with all three primary plant nutrients (nitrogen, phosphorous and potassium) needed in an easily dissolved form called NPK fertilizer.  Another procedure mixes ammonia with the nitric acid to produce a water solution of ammonium nitrate, which can be reduced into granules for use as nitrogen fertilizer. The yield in the production of acid with electricity is roughly 60 gm acid/KWH. If this acid is used to make 14 pounds of 20% nitrogen fertilizer, which normally sells for ~$14 retail, and 60% of this price goes for phosphate rock or ammonia, packaging, distribution, overhead and profit, the acid is worth roughly $0.18/kwh. As an example, each SEMAN could use 25 KW to produce acid. This electricity would produce 2376lbs/mo of acid with a volume of 25.7cu ft/mo (192gal). Thus the 25KW yields ~$3,240/mo for each SEMAN. More energy could be used for more profit, but the amount of acid that can be made is limited by the storage available for the acid produced in a month. Something between 25 and 50cu ft is expected to be practical. Also, the current use of fertilizer is ~40 million tonnes/yr (7300 million lbs/mo). Two hundred million SEMAN could produce 475000 lbs/mo of acid. Thus, only 3 million SEMAN are required to fill the demand using 25KW, so supply must be limited-a job that would fall to the AOTN network (see below). It should be noted that most of the nitrogen fertilizer produced now is made from natural gas-a fossil fuel-with carbon dioxide as an effluent. Replacing this process with SEMAN reduces the carbon dioxide production.

 

The Remaining Energy

The SEMAN capability is 100KW to 400KW. A capability of 200KW is expected to be the average generation capability. Starting with 200KW, and subtracting all the above power used for the purposes indicated, we end with 144KW available for other uses and making other products. For example:

  • Methanol can be synthesized and used as fuel from carbon dioxide in air and hydrogen obtained by electrolysis of water. The carbon dioxide is captured and purified from air by a technology developed by Global Research Technologies LLC
  • Hydrocarbons can be synthesized from carbon dioxide and water using a catalytic process that operates in something like an inverse fuel cell.
  • Carbon dioxide can be heated to split it into carbon monoxide and oxygen. The carbon monoxide can then be converted into hydrocarbons by use of the Fischer-Tropsch process.

With the 144KW available, 200 million SEMAN can provide most of the base load electrical energy needed in the world.

 

Another use that appears promising is weather control (see ap11 CLIMATE AND WEATHER CONTROL-July, this site).

 

A third potential use of the energy is to refine aluminum or zone-refine silicon for electronics. Both use are important users of electrical energy.

 

In any case, it is obvious that the SEMAN can be made both profitable for the owner and useful to mankind as a whole, however the energy it generates is used. The 200 million SEMAN that can operate on the oceans are sufficient to cover the world’s needs of energy, water, food and fertilizer up to 2050.

 

The Aquater Ocean Trade Network (AOTN)

The SEMAN will receive $400 for food, $100 for water, $224/mo for fuel oil, $216/mo for sequestering carbon dioxide, $3,240/mo for acid for fertilizer. This is a total of $4280/mo or $51,360/yr plus the products produced with the excess electricity. Note that the products of the SEMAN’s operation (food-20cu ft, water-140cu ft, liquid fuels-17cu ft, nitric acid-26cu ft, for a total of 203cu ft) are compact enough so that they can be stored on the SEMAN for about a month (SEMAN total volume is14,000cu ft), so the nodes in the Aquater Ocean Trade Network (AOTN) should be located within roughly a tenth of a month’s travel (~1000Nmi) of each other in SEMAN operation zones. These nodes would consist of cargo vessels on the ocean and special SEMAN ports on the seashore (see ap3a NEW LAND JOBS FOR THE COMING GENERATION-Jan, this site). Thus the operating procedure would require that products-food, water, fertilizer concentrate and fuel oil-would be stored for roughly one month and then delivered to central trade nodes either on the ocean or the shore- where Aquater goods could be sold and loaded onto a cargo vessels and transshipped to primary national ports for use. These transshipment nodes constitute the Aquater Ocean Trade Network (AOTN). The nodes would also be used to coordinate and pay for carbon dioxide sequestration, provide spare parts for SEMAN maintenance and repair and provide plastic for packaging dry ice for carbon sequestration. The nodes can finally be used to build new SEMAN and sell them.

 

SUMMARY AND CONCLUSIONS

In this paper, the world’s food, fresh water, fuel (energy) and fertilizer production systems are investigated. It is noted that these systems are currently operating in a non-sustainable mode and so need to be gradually revamped into a sustainable mode or humanity will face a serious problem in the future. The world’s current land based food and water systems need a gradual 15% to 20% replacement by sustainable systems. Furthermore, the world’s fertilizer and liquid fuel production systems are unsustainable and need to be gradually replaced by sustainable systems. Finally, it is necessary to sequester some of the carbon dioxide in the world’s atmosphere to eliminate the harmful effects of global warming.

 

The SEMAN, a vessel that harvests energy from the oceans, is proposed for these jobs. Here, we have looked at this long-term problem in depth to determine what can be done to produce a practical ocean trade network with these SEMAN to provide these products in a “green” way and thus avert this potential ecological disaster. It appears that the SEMAN can do these jobs, and a practical ocean trade network can be constructed for these SEMAN. This network will be called the Aquater Ocean Trade Network or AOTN. The operation details of this network have been provided in this paper.

 

Notes

  1. The design work for the SEMAN is done. The physical prototype of the SEMAN is nearly complete-see “SEMAN prototype”, this site, at the bottom of the home page. It is too early to start the AOTN.
  2. To donate to help complete this prototype, click “Add To Cart” on the home page.