Changing weather patterns have resulted in flooding in some parts of the world and drought in parts that include regions in the United States and Canada. Several plans have been devised over many years to transport water from regions of excess supply to regions that need water. During the 1950’s an engineer named Garrison proposed that a pipeline be built to transport water from parts of Northern Canada into dry regions of the United States. One of the problems with the proposed Garrison Diversion is that it would require water to be pumped uphill and along northbound rivers where hydroelectric power dams exist.

At the present time water levels in the Great Lakes are at their lowest levels in over a century. Diverting water south from these lakes would require energy and would also reduce hydroelectric generation capacity at 2-installations along the St Lawrence River system. There is however the need to generate more electric power for commercial, industrial and home markets and also to increase the availability of potable water. Reducing generation capacity is therefore not an option at the present time. Alternative means need to be implemented to provide water while maintaining and increasing generation capacity.

American and European companies have developed technology that can use seawater to cool the condensers in coal-fired thermal power stations. Such technology was used on ocean liners during the early 20th century and transferred to nuclear powered ships. This technology is used at thermal power stations across the Middle East to provide cooling capacity and to desalinate seawater. This well proven technology could be installed on a larger scale at several coal-fired and nuclear power stations across North America and that are located near an oceanic coast.

Corrosion-resistant pipelines could carry seawater inland to such power stations and to return brine to the ocean. Dry riverbeds may be dredged and deepened to create oceanic inlets. Connecting pipelines could carry seawater further inland from such inlets to provide cooling capacity to multiple power stations. The exhaust heat from these power stations could be used to desalinate seawater at competitive costs and be supplied to nearby populations. Heated brine could be returned to the ocean through pipelines that lead to similar adjacent inlets. It may be possible to generate electric power from ocean thermal energy conversion (OTEC) technology at such locations.

Manufacturers of large gas turbine engines are developing technology that can produce potable water from the waste heat and combustion gases. The temperature of the air downstream of a low-pressure turbo-compressor can reach 3000 F to 4000 F and can be used to desalinate seawater in an intercooler-desalination unit. The combustion exhaust gases can be cooled from over 5000 F to below 2000 F after having preheated water and generated saturated steam in the boiler of a bottom-cycle steam engine.

The water vapor in the combustion gases of natural gas can be condensed into potable water after its residual heat is used to desalinate seawater. Those gases could be condensed using air if the engine were operating in a cold climate. One manufacturer of large gas turbines is presently testing technology to condense potable water from the combustion exhaust gases. As well, the exhaust steam from the bottom-cycle steam engine would likely hold enough heat at sufficient temperature to desalinate seawater.

Air-cooled thermal power stations that use cooling towers are in operation in many locations across North America including in regions where humidity is high during the summer months. During summer heat waves the demand for power is at a peak. The output of some air-cooled power stations has to be reduced due to reduced cooling capacity of the cooling towers. New technology is being researched and developed may help alleviate this problem and assist in providing water to nearby populations.

A small prototype solar tower of 50-kw output has been in operation in Spain for several years. Test results indicate that the concept could be built to a much larger scale and generate greater output. A scale model prototype of a competing solar vortex engine was recently built in Utah where initial testing is underway. Research indicates that solar air engines can also operate on heat rejected by thermal power stations or on heat rejected by large capacity commercial refrigeration and district air-conditioning systems. Water that flows through insulated pipes would carry the heat to these engines.

Low-grade thermal air engines would simultaneously generate electric power while increasing the cooling capacity of cooling towers. They could enclose the cooling towers and circulate air through large wind turbines located at the base of the tower. The heated air would be propelled upward to higher elevation inside chimneys or towers built to heights of between 3000-ft and 5000-feet. A variant known as a vortex engine could produce equivalent output when built to a height of below 350-feet and up to 1300-feet diameter. It would generate a tornado to produces electric power and propel exhaust hot humid summer air up to the troposphere where it would cool and condense.

That moisture could precipitate into rainfall overnight and within a few miles of a power station that is cooled by a solar thermal tower or a vortex engine. Thermal power stations that are located in tornado prone regions could operate using a dual cooling system. The vortex engine may need to be shut down when weather conditions could spawn tornadoes. Seawater could be is pumped several hundred miles inland to be used for emergency cooling during such occasions. That water could be desalinated at such locations with the brine being returned to the ocean inside corrosion resistant pipelines.

There would be benefit in allowing thermal power stations to operate near peak output for greatly extended durations. The life expectancy of components used in thermal power stations could be greatly extended by maintaining them at constant temperature and pressure for prolonged periods. The off-peak power may be used to desalinate seawater using exhaust heat and by using reverse-osmosis technology. Off-peak electric power may be transferred into energy mega-storage reservoirs and also be used to pump seawater into holding tanks located at higher elevation.

The reverse-osmosis technology could desalinate that seawater during off-peak hours as well as during peak power periods. To save on fresh water some coastal municipalities have converted toilets to operating on seawater. This trend is likely to be expanded in the future and especially at locations where prolonged drought is likely. The overall cost of desalinating seawater using exhaust heat from thermal power stations as well as using off-peak power would need to be compared to the cost of transporting water through several hundred or thousand miles of pipelines or even importing water by tanker ship.

Convoys of tanker ships could carry potable water from the Amazon to the Southeastern United States during times of extended drought to supplement desalination technology. In the future many large American coastal cities and coastal cities elsewhere in the world will face shortages of potable water. Every year flooding occurs on many rivers around the world including the Mississippi, the Ganges and the Danube. The annual cost of flood damage could justify using energy to transfer some of this water into storage.

Floodwater from the northern sections of the Missouri and Mississippi could be pumped into Lakes Superior and Michigan except the presence of Asian carp in those rivers may present new challenges. Every year during the summer monsoon floodwater submerges and devastates entire regions across southeastern Asian countries. Scope exists whereby wealthier nations could invest in hydroelectric and dam development on some of these flood prone Asian rivers to reduce the annual devastation, provide local power and secure a source of water that can be exported.

Conclusions

In the future water resources development will be more closely linked to the power generation industry. The two services would eventually become synonymous with each other. Access to energy mega-storage capacity would assist in the desalination of seawater. Off-peak electrical power from thermal and non-thermal power stations could be transferred into storage or to operate reverse osmosis technology. Exhaust heat from thermal power stations could activate seawater desalination technologies while their companion thermal air engines generate power and propel humid air to high altitude where it would condense. In the future some regions in developed nations may obtain a large amount of their fresh water from a combination of desalination technologies, water pipelines and ocean-going tanker ships that import potable water.

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