Methods of making hot and warm air from renewable energies abound. Commonly referred to as solar, wind, biomass, or geothermal, or tidal energy; renewable energy can make hot air, compress air, and blow air. Nix in U.S. Pat. No. 5,308,187 (issued May 3, 1994) outlines a method of reducing fuel consumption for a fossil fuel burner. Air is pre-heated by solar energy, using a parking lot like surface. The transparent clear covering heats an opaque thermal conducting mass. This thermal conducting mass then transfers heat to underground pipes. The hot air is sucked into a firebox in a coal burning power plant. The pre-warmed air reduces the amount of fuel that needs to be burned. The invented device improves upon Nix, to include higher temperatures, and higher compression of the air. This makes for a more efficient combustion, reducing the amount of carbon dioxide created, and also reduces drastically the amount of fossil fuels needed.
Cottle in U.S. Pat. No. 608,755 (issued Aug. 9, 1898) shows an early application of solar concentrated heat. A tracking reflector concentrates sunlight into a window to heat rocks to a high temperature.
McCabe in U.S. Pat. No. 3,757,516 (issued Sep. 11, 1973) illustrates how geothermal energy can be utilized. A fluid is moved through a geothermal formation to make a hot saturated vapor.
Rigollot in U.S. Pat. No. 3,757,517 (issued Sep. 11, 1973) shows a power plant that uses stored compressed air for off-peak power.
Gaydos in U.S. Pat. No. 3,815,574 (issued Jun. 11, 1974) shows a solar collector that is simple in design. Pipes buried in sand, with iron oxide, make a hot fluid. The sand is underneath a clear glass surrounded by an insulating box.
Rushing in U.S. Pat. No. 3,843,238 (issued Oct. 22, 1974) shows a tension frame solar reflector, which can be used to reflect more sunlight onto a solar collector, thus increasing heat.
Glickman in U.S. Pat. No. 3,903,700 (issued Sep. 9, 1975) shows a sunshine powered hydro electric power plant. The expansion of a working fluid drives a pump for water. The water, when flowing downwards, generates electrical power.
Sadan in U.S. Pat. No. 3,966,541 (issued Jun. 29, 1976) shows a method of concentrating salt brines with ponds that evaporate water with solar energy. The result is to optimize recovery of chemicals.
Kapany in U.S. Pat. No. 3,985,116 (issued Oct. 12, 1976) shows a high efficient flat plate type solar collector. Light is concentrated so as to create greater temperatures.
Bard in U.S. Pat. No. 3,985,118 (issued Oct. 12, 1976) shows a solar furnace using concentrating fresnel lenses. Thus, steam is generated.
Oakes in U.S. Pat. No. 3,985,119 (issued Oct. 12, 1976) illustrates a line focus type parabolic solar collector. The reflection from the parabolic onto a pipe target creates high temperatures.
Jahn in U.S. Pat. No. 3,998,206 (issued Dec. 21, 1976) shows a point focus type parabolic solar collector, or dish type. A tracking mechanism points the parabolic at the sun, which then reflects the concentrated sunlight onto a spherical boiler with a shield, creating very high temperatures.
Arthur in U.S. Pat. No. 4,010,614 (issued Mar. 8, 1977) illustrates a power plant that pumps water uphill using solar energy. The water when traveling downhill generates electrical power.
Coleman in U.S. Pat. No. 4,026,267 (issued May 31, 1977) illustrates a solar energy apparatus that uses lens to focus solar radiation unto fiber optics. This is used to heat a heat sink for thermal storage.
Drew in U.S. Pat. No. 4,038,964 (issued Aug. 2, 1977) shows a parabolic solar collector that uniquely has an interior flat plate solar collector. Thus, the solar collector is able to capture not only direct sunlight, but also indirect sunlight (like from clouds). The entire assembly is covered by glass, thus is able to trap short-wave solar radiation.
O'Neill in U.S. Pat. No. 4,069,812 (issued Jan. 24, 1978) shows a prismatic, line focus, fresnel lens solar concentrator. Light is focused onto a heat transfer pipe.
Scragg in U.S. Pat. No. 4,070,861 (issued Jan. 31, 1978) shows a solar reactor combustion chamber, where concentrated sunlight is used to combust a chemical. The heat and pressure then drives a turbine.
Derby in U.S. Pat. No. 4,079,591 (issued Mar. 21, 1978) shows a solar power plant, which utilizes a sun tracking parabolic collector and a plurality of energy storage and conversion devices. A compressed superheated gas is generated.
Bennett in U.S. Pat. No. 4,080,957 (issued Mar. 28, 1978) shows a solar collector that boils a liquid inside an evacuated enclosure.
Fletcher in U.S. Pat. No. 4,091,798 (issued in May 30, 1978) shows a non-tracking solar energy collector system, where reflectors reflect light onto a system of vacuum jacketed receivers.
Knowles in U.S. Pat. No. 4,119,085 (issued Oct. 10, 1978) shows a solar collector tube with an interior heat pipe.
Mahdjuri in U.S. Pat. No. 4,122,831 (issued Oct. 31, 1978) shows an elongated evacuated transparent tube for collecting solar energy.
Keith in U.S. Pat. No. 4,141,185 (issued Feb. 27, 1979) shows a flat plate solar collector with an interior evacuated passageway with cavities.
Keller in U.S. Pat. No. 4,149,856 (issued Apr. 17, 1979) shows a method of making a gaseous fuel using sunlight and steam.
Korr in U.S. Pat. No. 4,159,629 (issued Jul. 3, 1979) shows a huge solar collector floating on top of a floating boat. The water allows for effective tracking of heavy and large solar collectors. An island in the middle has pipes carrying the working fluid from and to the solar energy focus.
Seidel in U.S. Pat. No. 4,167,856 (issued Sep. 18, 1979) shows a solar thermal power plant using an open-air circuit. The solar energy drives a compressor and a gas turbine. Optionally, fuels can be burned in a combustion chamber.
Wood in U.S. Pat. No. 4,171,876 (issued Oct. 23, 1979) shows a large curved solar parabolic using a plurality of straight rod-like elements. A tracking support structure supports the reflector in the correct orientation to the sun.
Boblitz in U.S. Pat. No. 4,172,442 (issued Oct. 30, 1979) shows a tiered passage way for heating a gas or liquid.
Sommer in U.S. Pat. No. 4,172,443 (issued Oct. 30, 1979) shows a tower with a plurality of mirrors focusing the sun's rays to the top of the tower. Generated are very high temperatures.
Zenty in U.S. Pat. No. 4,177,120 (issued Dec. 4, 1979) shows the art of converting coal to a gas via solar energy.
Ratliff in U.S. Pat. No. 4,184,479 (issued Jan. 22, 1980) shows a greenhouse capable of storing solar heat.
Penny in U.S. Pat. No. 4,220,136 (issued Sep. 2, 1980) shows a line focus type parabolic solar collector that also is able to absorb solar radiation with an interior flat plate solar collector.
Braun in U.S. Pat. No. 4,211,212 (issued Jul. 8, 1980) shows how solar energy can be used to drive an absorption cycle refrigeration system.
Margen in U.S. Pat. No. 4,227,511 (issued Oct. 14, 1980) shows a solar collector system that tracks the sun while floating on a liquid. The liquid also acts as thermal storage of the sun's heat.
Maes in U.S. Pat. No. 4,242,833 (issued Jan. 6, 1981) shows a solar greenhouse for cold climates.
Stone in U.S. Pat. No. 4,251,135 (issued Feb. 17, 1981) shows a tension frame solar planar reflector. The triangular shape frame can be used as a heliostat for focusing the sun's rays on top of a tower.
Yoshida in U.S. Pat. No. 4,256,174 (issued Mar. 17, 1981) shows a method of heating and cooling sand using a system of heat exchangers.
Finckh in U.S. Pat. No. 4,259,836 (issued Apr. 7, 1981) shows a solar power plant using an open gas turbine circuit. The solar power plant has a compressor, a solar heater, a combustion chamber and a turbine and generator for heating compressed air.
Jubb in U.S. Pat. No. 4,262,484 (issued Apr. 21, 1981) shows a gas turbine, which uses compressed air heated by solar energy.
Bachli in U.S. Pat. No. 4,270,524 (issued Jun. 2, 1981) shows a hollow evacuated tube with an interior solar energy absorber.
Synder in U.S. Pat. No. 4,276,122 (issued Jun. 30, 1981) shows how solar energy can be used to distill water.
Wood in U.S. Pat. No. 4,295,709 (issued Oct. 20, 1981) shows a parabolic concentrating collector using a plurality of triangular reflecting panels, supported by a tracking framework.
Hutchison in U.S. Pat. No. 4,297,1981 (issued Oct. 27, 1981) shows a trough line focus type solar collector. Unique is a stressed skin monocoque construction.
Dobson in U.S. Pat. No. 4,300,539 (issued Nov. 17, 1981) shows a solar collector made of glass fiber reinforced concrete.
Crandon in U.S. Pat. No. 4,303,057 (issued Dec. 1, 1981) shows a method of focusing sunlight onto a swimming pool. It represents methods of heating water in swimming pools at low temperatures.
Reinert in U.S. Pat. No. 4,306,542 (issued Dec. 22, 1981) shows a solar greenhouse design, which removes unwanted heat.
Goldstein in U.S. Pat. No. 4,318,393 (issued Mar. 9, 1982) shows a porous surface receiver placed on top of a tower. Heliostats focus the sun's rays onto the receiver. Atmospheric air is used as the working fluid.
Jardin in U.S. Pat. No. 4,326,501 (issued Apr. 27, 1982) shows a solar furnace design. Pipes are embedded in a tank for thermal storage.
Wirguin in U.S. Pat. No. 4,328,788 (issued May 11, 1982) shows a heat storage pond using a saturated aqueous saline solution for storage of solar heat.
Moore in U.S. Pat. No. 4,328,791 (issued May 11, 1982) shows a tank for storing solar heat, which is supplemented by a fossil fuel burner and firebox.
Mori in U.S. Pat. No. 4,340,812 (issued Jul. 20, 1982) shows a light energy collection apparatus to focus the sun's rays into fiber optics.
Whiteford in U.S. Pat. No. 4,358,183 (issued Nov. 9, 1982) shows a solar reflecting panel with a tensioning frame.
ElDifrawi in U.S. Pat. No. 4,363,703 (issued Dec. 14, 1982) shows a solar energy desalination process for solar evaporation of salt water.
Wood in U.S. Pat. No. 4,372,772 (issued Feb. 8, 1983) shows a solar parabolic reflector comprised of a plurality of triangular reflecting members.
Drost in U.S. Pat. No. 4,394,859 (issued Jul. 26, 1983) shows a central solar energy receiver on top of a tower which uses fin shaped slats. Heliostats focus the sun's rays onto the receiver.
Van der aa in U.S. Pat. No. 4,421,099 (issued Dec. 20, 1983) shows a solar collector heat pipe with an evaporator.
Posnansky in U.S. Pat. No. 4,421,102 (issued Dec. 20, 1983) shows a quartz glass pipe for concentrated sunlight.
Aiman in U.S. Pat. No. 4,415,339 (issued Nov. 15, 1983) shows a solar coal gasification reactor to create gaseous fuel.
Platell in U.S. Pat. No. 4,445,499 (issued May 1, 1984) shows a method of storing solar heat in the ground using pipes.
Assaf in U.S. Pat. No. 4,475,535 (issued Oct. 9, 1984) shows a solar pond which is segregated.
Snook in U.S. Pat. No. 4,481,774 (issued Nov. 13, 1984) shows a solar canopy over a canyon. The uprising of solar heated air drives large turbines.
Kitzmiller in U.S. Pat. No. 4,514,914 (issued May 7, 1985) shows a method of converting a typical electric or gas clothes dryer to be powered by solar heat.
Slemmons in U.S. Pat. No. 4,515,151 (issued May 7, 1985) shows a fiber reinforced concrete solar collector.
Dobson in U.S. Pat. No. 4,559,882 (issued Dec. 24, 1985) shows a biomass fuel furnace. Heat exchangers remove moisture from the biomass. The air is preheated for combustion via exchangers.
Sankrithi in U.S. Pat. No. 4,581,897 (issued Apr. 15, 1986) shows a solar power collection apparatus that uses heliostats that focus the sun's rays onto a tethered aerostat.
Qader in U.S. Pat. No. 4,582,590 (issued Apr. 15, 1986) shows a method of heating oil shale with solar energy. The resulting pyrolysis process creates an useful gaseous and liquid fuel.
Bronstein in U.S. Pat. No. 4,596,238 (issued Jun. 24, 1986) shows an interiorly tensioned solar reflector, which forms a line focus parabolic collector.
Percival in U.S. Pat. No. 4,602,614 (issued Jul. 29, 1986) shows a hybrid solar combustion receiver for a hot gas engine.
Moore in U.S. Pat. No. 4,649,899 (issued Mar. 17, 1987) shows a turntable frame to track the sun and to point solar cells at the sun.
Butler in U.S. Pat. No. 4,671,025 (issued Jun. 9, 1987) shows a greenhouse roof construction method.
Hisken in U.S. Pat. No. 4,786,205 (issued Nov. 22, 1988) shows a method of conserving water in remote locations.
Kurashima in U.S. Pat. No. 4,786,795 (issued Nov. 22, 1988) shows a method of tracking the sun by floating solar cells on top of a liquid.
Tindell in U.S. Pat. No. 4,841,731 (issued in Jun. 27, 1989) shows a solar powered system where hydrogen and oxygen are combusted, thus to drive a turbine. Photovoltaic cells drive an electrolysis generator, which manufactures hydrogen and oxygen from water.
Wright in U.S. Pat. No. 4,875,298 (issued in Oct. 24, 1989) shows a pre-heater for a clothes dryer. Valves are used to either draw air from solar heated attic space, or from ambient air to the air inlet of the dryer.
Vanzo in U.S. Pat. No. 4,910,963 (issued in Mar. 27, 1990) shows a solar energy system utilizing cyrogenic hydrogen and oxygen. Solar energy is used to power the electrolysis and cyrogenic cooling equipment.
Andersen in U.S. Pat. No. 4,979,494 (issued Dec. 25, 1990) shows a parabolic dish type solar collector used to cook food.
Bronicki in U.S. Pat. No. 4,942,736 (issued Jul. 24, 1990) shows how solar energy can heat a gas for a gas turbine using a rotating ceramic.
Travis in U.S. Pat. No. 5,058,675 (issued Oct. 22, 1991) shows a method for destructive distillation of kerogen. A large reflector, on tracks, focuses the sun's rays onto a boiler.
Michel-Kim in U.S. Pat. No. 5,089,030 (issued Feb. 18, 1992) shows a method of gasification of a solid fuel, using a pre-combustion chamber and pre-heated air.
Pitt in U.S. Pat. No. 5,161,520 (issued Nov. 10, 1992) shows a solar powered steam generator for pumping ground water for rural areas.
Vitale in U.S. Pat. No. 5,228,293 (issued Jul. 20, 1993) shows a solar to electric power conversion system using a stirling cycle. An auxiliary fossil or biomass heater can be used to supplement.
Karni in U.S. Pat. No. 5,323,764 (issued Jun. 28, 1994) shows a central solar receiver for concentrated sunlight.
Rogers in U.S. Pat. No. 5,325,844 (issued Jul. 5, 1994) shows a lightweight tracking solar collector of the point focusing type. Numerous plates focus the sun's rays via a bicycle wheel type structure.
Bellac in U.S. Pat. No. 5,384,489 (issued Jan. 24, 1995) shows a wind powered electricity generating system with a thermal fluid heated by a heater.
Bharatham in U.S. Pat. No. 5,417,052 (issued May 23, 1995) shows a hybrid solar central receiver. The power plant also uses molten salt as the heat transfer medium. Air is pre-heated for a gas compressor.
Moore in U.S. Pat. No. 5,444,972 (issued Aug. 29, 1995) shows how a solar central receiver can manufacture steam for a turbine. Alternatively, fossil fuel can be used.
Bronick in U.S. Pat. No. 5,448,889 (issued Sep. 12, 1995) shows a method of producing compressed air using solar energy.
Edelson in U.S. Pat. No. 5,454,853 (issued Oct. 3, 1995) shows use of energy sources like wind, solar, hydro, or off peak conventional power to manufacture steel.
Nix in U.S. Pat. No. 5,488,801 (issued Feb. 6, 1996) shows how a solar powered photovoltaic fan can cool a solar greenhouse, and move air.
Johnson in U.S. Pat. No. 5,551,237 (issued Sep. 3, 1996) shows a method of producing hydroelectric power, where solar produced steam is used to displace water operating a hydro turbine.
Ross in U.S. Pat. No. 5,685,151 (issued in Nov. 11, 1997) shows a method of concentrating solar heat using sodium chloride. A concentrating parabolic dish type collector focuses the sun's rays onto the fluid.
Bronicki in U.S. Pat. No. 5,704,209 (issued Jan. 6, 1998) shows a method of compressing and heating air for an externally fired gas turbine. Solar energy can also supplement. Steam is generated.
Johnssen in U.S. Pat. No. 5,707,762 (issued Jan. 13, 1998) shows a method of generating electricity from solar grown biomass.
Shuler in U.S. Pat. No. 5,734,202 (issued Mar. 31, 1998) shows a method of generating electricity utilizing a re-circulating air tunnel. The kinetic energy of the wind stores energy for electrical power generation.
Assaf in U.S. Pat. No. 5,755,102 (issued May 26, 1998) shows a method of producing power from concentrated brines. Evaporated water is flashed into steam for a turbine.
Cohn in U.S. Pat. No. 5,857,322 (issued Jan. 12, 1999) shows a hybrid solar and fuel fired electrical system.
Falbel in U.S. Pat. No. 6,019,319 (issued Feb. 1, 2000) is typical of flywheel technology, where energy is stored in a rotating mass.
Steinmann in U.S. Pat. No. 6,141,949 (issued Nov. 7, 2000) shows a process for using solar energy in a gas and steam power station.
Bronicki in U.S. Pat. No. 6,321,539 (issued Nov. 27, 2001) shows a retrofit for reducing the consumption of fossil fuel by a power plant using solar energy. Compressed air is heated by solar energy, driving a turbine. Hot gases create steam.
Bellac in U.S. Pat. No. 6,484,506 (issued in Nov. 26, 2002) shows a solar power enhanced combustion turbine. Air is cooled by solar energy.
Merswolke in U.S. Pat. No. 6,672,054 (issued Jan. 6, 2004) shows a wind powered hydroelectric power plant. Wind turbines create compressed air. Large storage tanks are used to regulate high-pressure liquid flow to a turbine electric generator.
Lawheed in U.S. Pat. No. 6,672,064 (issued Jan. 6, 2004) shows a system for converting solar energy to electric and thermal energy.
Keeton in U.S. Pat. No. 6,676,837 (issued Jan. 13, 2004) shows a solar powered aeration system that can keep lakes aerated for aquaculture.
Bronicki in U.S. Pat. No. 6,694,738 (issued Feb. 24, 2004) shows a retrofit system for reducing fossil fuel consumption for a power plant using solar radiation.
Mehos in U.S. Pat. No. 6,739,136 (issued May 25, 2004) shows a hybrid solar fossil fuel receiver, which combines pre-heats the air-fuel mixture. A heat exchanger provides heat for the hybrid arrangement.
Fairlie in U.S. Pat. No. 6,745,105 (issued Jun. 1, 2004) shows an energy distribution and control network for hydrogen fuel.
All of the above art show that all the components necessary for the invented device exist. Existing power plants, as coal burning power plants, smelters, oil refineries, and other industrial plants can be converted economically to renewable energies using the mentioned patented technologies. All of these technologies can be employed to pre-heat air for combustion. When air is pre-heated, and compressed and piped long distance to a fossil fuel burner, not as much fossil fuel is necessary to burn in an industrial firebox. Alternatively, commercial and residential buildings can be converted to integrate pre-heated, compressed hot air so as to reduce fossil fuel consumption. Typical appliances like gas hot water heaters, gas clothes dryers, or furnaces can be converted to integrate make-up air for combustion, where the make-up air is manufactured from renewable energies. The disclosed invented device shows a new and novel method of creating combustion air for use by mankind.
The invented device improves upon Nix, U.S. Pat. No. 5,308,187 (issued May 3, 1994). Nix claims a system of heating air with solar energy and for supplying air to a fossil fuel burner. However, the system described only supplies air in the low temperature range. To adequately power a large-scale power plant, a coal burning power plant will need temperatures on upwards above 750 F degrees. Often the interior of a firebox of a coal power plant can approach 1,000 F degrees. By pre-heating air to high temperatures, it can reduce significantly the amount of coal burned. And also it will reduce the amount of carbon dioxide gases generated, and reduce pollution. Alternatively, the same technology can pre-heat air for common household appliances like a gas hot water heater. This invented device is not unlike a common utility, like underground water, natural gas, fiber optic, electrical power, or other utilities. It is proposed that the color code “deep purple” be assigned for the invented device's pipes.
It is common knowledge that hot air can be made from solar energy. Hot air made from solar energy in the low temperature range (100 to 200 F degrees) is fairly inexpensive. Often times apex heat of a greenhouse or house attic can be sucked into a pipe. However, when hot air is manufactured in the 750 F or hotter range, concentrating solar collectors can be very expensive. What is proposed is a system of different types of solar collectors, each designed to gradually heat air, in stages. This will make production of hot air more economic. Whichever type of solar collector, that is the most cost effective for a particular temperature range, is used. More lower cost solar collectors pre-heat the air for higher cost solar collectors.
The goal of the invented device is to employ various energy sources, like wind, solar, geothermal, tidal energy, or biomass energy, to manufacture hot air for combustion 24 hours a day, year long. The concept is to develop various modular systems, which then can be picked and chosen, depending on local economics and land use. For example, if the site for the large power plant has extensive solar energy, but lacks hydropower or wind energy, then solar collectors can be emphasized. If however, the region is stormy, with lots of rainfall, then hydropower and wind energy can be emphasized. Developed, are approximately, but not necessarily, 100 ft by 100 ft land area size modules. Each module is of one type of solar, wind, or geothermal, biomass, or hydropower (or other renewable energy) systems. Each module is tailored to that particular degree range to manufacture hot air. Whichever is most cost effective is built. For example, greenhouse air is cost effective for warming air in the 100 F degree range, but ineffective at producing temperatures in the 500 F degree range. Each step of the way, air is pre-warmed by the module. The greenhouse air could pre-heat air to a higher temperature solar collector, flat-plate or concentrator type. This allows for the use of lower cost low temperatures solar collectors, thus downsizing the need to spend more money on higher cost high temperature solar collectors.
In order to power a large coal burning power plant, or other fossil fuel fire boxes, it will be necessary to utilize large amounts of land area. It is proposed that these solar collectors be constructed on top of “brown land” or land that has been environmentally wrecked, like a coal strip mine. It is proposed that recycled materials, such as recycled glass or fly ash, be used in the construction. As the coal is stripped from the land, this solar collecting “farm”, would be built on top. This step can be done as part of the land reclamation process. A parking lot like solar collecting paving, for example, can be placed on top of the coal strip mine. Underneath pipes transport hot air from solar collectors. The paving acts as mounting for solar collectors or wind turbines. The paving also acts as a “hot blanket”. The goal is to keep underground pipes and ground hot. Often times the amount of sunlight falling on a coal strip mine is several times more than the electrical power generated. Often times the amount of sunlight falling on a lake behind a hydro-dam is several times more than the electrical power generated.
The net result is hot, compressed and high velocity air is manufactured for combustion. These underground pipes are not typical; they will need insulation. These pipes when transporting hot air, are surrounded by thick insulation, and are buried in dry insulating soil. The goal is to use renewable energy to 1) heat air, 2) compress air, and 3) make air high velocity. Thus the energy is captured and blown at the fossil fuel burner. It is common knowledge that when air is hot, that air will expand. At sea level, and at 67 F degrees, air has a density of approximately 0.075 pounds per square foot. However, when air is heated to higher temperatures (at atmospheric pressure), the air can weigh as little as 0.02 pounds per square foot. It is this principle that makes hot air balloons float. The air expands and attempts to consume more volume.
However, when air is heated in an enclosed volume, like a pipe, the air increases in pressure. Alternatively, the air also flows at a higher velocity down the pipe. This is not unlike a jet aircraft turbine. A jet aircraft engine will suck, compress, heat and blow. It is proposed that renewable energies be employed to heat air, and also make the air compressed and high velocity, much like a jet aircraft turbine.
In order to capture the heat, the pipes must necessarily be heavily insulated. For example, a one feet diameter pipe will necessarily be surrounded by 2 feet of insulation (above R-100). This insulation will necessarily have to be shielded and made waterproof, in that water via convection can rob the pipe of heat. Thus a double pipe system is proposed. The interior pipe can be made of metal, much like that used for water pipe. The metal pipe is surrounded by insulation. The exterior pipe is then made of cement or concrete. Wherever practical, recycled materials are used.
The net result is the energy is transported via three methods: 1) heated air, 2) compressed air, and 3) high velocity air. At the fossil fuel burner the energy is recovered from the air. The heated air is used to warm and make hot the fossil fuel. The energy from compression is recovered at the fossil fuel burner, much like that of a spring being recoiled. Finally, the velocity of the air is recovered. When air travels down a pipe, much like a water pipe, the kinetic energy can be measured in foot-pounds. One foot-pound of traveling mass would be a pound of air, traveling one foot. It takes several cubic feet to make one pound of air, at atmospheric pressure. Compressing the air helps to create a pound of air in a smaller volume. This compression also increases the temperature. The key is when fuel is mixed with the hot, compressed and high velocity air; the fuel air mixture is effective for combustion. By transporting energy via this method, it avoids more expensive heat transfer methods as melted salts, or hot oil, or steam pipes. Air is a cheap heat transfer fluid, commonly available. If for example, there is a leak of heat transfer fluids, it would be expensive to replace. Air on the other hand is inexpensive to replace.
One major concern is when air is heated and compressed that it not cause the pipes to start melting or cracking from the extreme pressure and heat. Air should not travel faster than the speed of sound in pipes. Air should not be higher pressure that now commonly used for water pipes. Consequently, it is proposed that air not be heated more than 750 F degrees, or compressed more than ten atmospheres. But these temperature ranges can be exceeded with special pipes and materials.
It is common knowledge that a coal burning power plant can suck in tens of thousands of cubic feet of air in a minute. A coal burning power plant can potentially suck in 10,000 to 100,000 cubic feet of air in a minute. That is a lot of air. In order to deliver the same amount of pounds of air, large insulated pipes would be necessary. It is possible to use upwards to ten separate 3 feet diameter pipes for the pre-heated air to meet the demand of a large coal burning power plant. With insulation each of these pipes can approach ten feet in diameter, with close to 3 feet of insulation surrounding 3 feet diameter hot air pipes.
Presently, power plants must necessarily use parasitic electricity to power large blowers that feed the flames of a firebox. With these insulated pipes, that parasitic energy for these blowers would be unnecessary.
With the air already pre-heated, it will necessitate the relocation of existing heat exchangers and economizers. These insulated pipes do not eliminate the function of heat exchangers or economizers, but reallocates their function. For example, with air already hot before going to the firebox, the slow rotating economizer can now heat air for another purpose. Pre-boilers, which pre-heat the main boilers water to the triple point, can have the air pre-heated by the air from the economizer, instead. (The triple point is the exact temperature and pressure where water is still liquid and steam). This triple point water is highly pressurized. When placed into tubes buried in the coal power plants firebox, the heat from the combustion and hot air flashes the water to make steam. The high-pressure steam in turn drives the turbines to make electrical power. The goal is not to have exhaust travel out the stacks above 300 F degrees, but recover the heat usefully. Exchangers and economizers will necessarily have to be reengineered in function.
It is envisioned that pre-heated combustion air may necessarily have to be piped from long distances, not unlike long distance water pipes or electrical power lines, or long distance pipelines. Thus it is proposed that large diameter transmission lines for combustion air be developed. These transmission pipes could potentially pipe heated air 750 F, at 10 atmospheres, and upwards toward 1,000 feet per second. Key to these transmission lines is to avoid placing them in moist soil. Water can potentially rob the underground pipes of heat, thus cooling the interior hot air. But the concept of long distance transmission for combustion air is feasible.
Part of the reason for heavily insulating the pipes is that the air when it travels through the pipe, it creates friction. The air molecules bounce off the surface of the interior of the pipes. The higher pressure, the more the air molecules bounce. The friction creates additional heat, thus heating the pipes even more. The pipes are not only heated from the heat of the hot air, but also from the friction of the air moving against the pipe surface. The goal is to make air so it flows laminar, not turbulent. Like a clarinet when played, the pipes when cold will provide great resistance. But when the pipes are hot, the resistance to the moving air will be greatly decreased. The purpose of the insulation is to make sure the pipes remain hot, once made hot. Hot pipes make the moving mass of the compressed air more slippery, or increase the viscosity. Cold pipes can act much like ice blocking the flow of water. Cold pipes can make the air flow more turbulent, while hot pipes can make the air flow more laminar. At startup, some of the heat from the air will necessarily be used to make the pipes hot. It will take some energy to make the pipes hot, but once the pipes are hot, the pipes will stay hot from the thermal mass. The hot pipes should be an effective method of energy transfer. When air travels at 100 to 1000 feet per second, it means that hot air can be manufactured from renewable energy farms several miles away. It may be possible to transmit combustion air 50 to 100 miles away. For example, when air travels at 100 feet per second, the air will travel 6,000 feet within one minute, or about a mile a minute, or 60 miles per hour.
The ambient air when sucked into the invented device does not have to be dry air. It can be moist air, saturated, like humid vapor. Greenhouse air can be moist from plants and evaporation of water. Thus air sucked in from the greenhouse can be moist and humid. Sucking into the invented device moist saturated air makes for more efficient heat transfer. Water has a greater mass, or specific heat than dry air. The water thus can carry heat better. In effect, the invented device uses both water and air for heat transfer. The added water also helps in the combustion of fossil fuel.
Another feature of the invented device is the air can be processed so as to include more oxygen. A greenhouse makes air oxygen rich from the oxygen producing plants. The air can be sucked in from the greenhouses with this oxygen rich atmosphere. It is common knowledge that plants make oxygen from breaking down carbon dioxide in air via photosynthesis. The addition of moisture and oxygen to the combustion air is another method of energy transfer. The invented device thus transfers energy five ways, instead of just three: 1) heat, 2) pressure, 3) high velocity, 4) water vapor and 5) oxygen.
Solar energy can also be used to modify, the local climate beneficially. With large amount of paving area, and large amounts of solar collectors, the invented device will create a huge watershed. The water from the watershed can be captured by hydro-dams. The captured water can then be used by the greenhouses, or by agriculture. The watershed will also help generate hydropower, which in turn can be used to make additional combustion air.
Of noteworthy consideration, there is a huge underground aquafier of salt/alkaline water underneath the American West (and also African Sahara). This water is deep underground, below sea level. Wells, for pumping this water to the surface can drill down to access it. By using solar and wind-powered pumps, this salt/alkaline water can be pumped to the surface. Once pumped to the surface, this salt/alkaline water can be placed in basins or ponds. The water is evaporated by sunlight, helping to modify the local climate, thus increasing the local rainfall and morning fog. This adds moisture to the region, but also helps drought protect the local area. The added moisture helps local agriculture, greenhouses, and also adds fresh water to hydro-dams. Commonly referred to as heliohydroelectric technology, the use of underground salt/alkaline water resources can help create additional combustion air. For example, a small hydro-dam can compress ambient air via rotation of a hydro-turbine and fan/blower/impeller combination. A second water hydro-turbine can generate electrical power. The resulting electricity heats a heating element, which in turn makes the hot air from the other hydro-turbine hot. This is not unlike a giant hair dryer. The condensation of morning fog and rainwater (that was generated by the heliohydroelectric evaporation ponds) thus converts to heat, compressed and high velocity combustion air. Thus artificial local rainfall can be created to make combustion air.
Optionally, wind energy can be used to make combustion air. Wind turbines can generate electrical power, which in turn can power a resistive electric element. This element can then heat ambient air for combustion in a “hot air oven”. The wind turbine can also power blowers/impellers/fans, which blow the air through the hot air oven. Flywheels can be coupled to the blower, thus when wind is unavailable, the stored rotational energy of the flywheel will keep the air moving.
The burning of biomass can also help create combustion air. The biomass, perhaps from the greenhouses, would heat combustion air via an exchanger. This would provide combustion air when solar or wind energy is less available. Unique is the concept of a remotely located biomass combustor that could be located miles away from a large power plant. The concept of use of exhaust to pre-heat air for combustion is not new, but what is new is the concept of creating combustion air from a large distance away.
Optionally, geothermal energy can be utilized to manufacture combustion air. A rotating compressor would inject air into a hot geothermal formation via injection pipes. A second pipe would extract the hotter air, and then drive another turbine. This “energy recovery turbine” would then drive the rotating compressor. The resulting hot air is piped via insulated pipes to the distant power plant.
Optionally, hydrogen fuel can be made from solar, wind, or biological energy sources. Thus, potentially fossil fuels could be replaced by hydrogen. All of these steps make for a complete energy system to convert a large-scale coal burning power plant (or other fossil fuel fire boxes). Coal plants can be very polluting. By converting the power plants to renewable energy, it will eliminate the need for additional coal strip mining. It will also help extend the life of existing coal strip mines, making for a very economically combination. It will also help reduce the cost and size of air pollution equipment.
It should be noted that each of these modules are incrementally installed. In the first year, 10% of the power plant heat could be powered by renewable energy. The next year 20% of the heat load would be converted. Each incremental step is built within a period of time. As each incremental step is built, it is revenue producing almost immediately, thus helping financing the project. For large coal burning power plants, it will take several years to convert. During that period the cost of capital can be recovered, before the next module is built. Incremental steps help recover the cost of construction sooner. This invented device is a retrofit to almost any fossil fuel burning power plant. It's primary intent is for “external combustion engines”, like steam plants, or hot water heaters. It is not intended for “internal combustion engines”.
All of the above make for a complete energy system that can be retrofitted to almost any fossil fuel burner. Worldwide, nearly 97% of mankind's energy comes from combustion of oil, gas or wood, or coal. Practically, any firebox can be retrofitted with this device. In it's simple form, a wood stove can suck air from an exterior solar flat plate collector. When air is sucked from outside, it is already hot, not cold, from the solar collector. It means not as much firewood has to be chopped to heat a room. Another example is a hot water heater. When air is sucked or blown into the firebox of a natural gas hot water heater, it makes the water hot. However, at night or winter, small amounts of fossil fuel can be burned to make up the heat difference. Thus, pre-heated air from solar energy can supplement fossil fuels.
Pre-heated air from renewable energies has applications more than just coal burning power plants. It can be used for household appliances like clothes dryers, hot water heaters, furnaces, building exchange air, food drying, cooking food, water distillation or to power an absorption cycle air conditioner/refrigerator. Combustion air can be useful for oil refineries in processing gasoline, plastics, or fertilizers. By integrating solar and other renewable technologies, it allows for oil, gas and coal to be used more as a material, than as a fuel. The addition of renewable energies to industrial process heat will help extend existing geologic resources of oil, coal and gas, and also help reduce the need for high cost exploration. In effect, the invented device will aid, not replace, the existing fossil fuel industry. The invented device helps reduce air pollution, and also drastically reduces carbon dioxide emissions.
Key to developing the invented device is economics. Key is to integrate “dual economics”. A greenhouse, for example, not only creates warm and moist oxygenated air, it also produces plants, biomass and food. The greenhouse becomes self-financing, giving combustion air as a bonus. A solar pond, of salt water, captures solar heat. The salt water also creates moisture. The overhead inflatable greenhouse over the solar pond can recover the moisture via distillation. The condensate from the cooler greenhouse creates fresh water. The fresh water then is “sold”. A flat plate farm can be the roof of a warehouse. Wind farms can also be a cattle pasture. Thus, the land can be more productive and more economic. A hydro-dam allows for fish farming. The net result is overall reduction in the cost of manufacture of combustion air.
It should be noted that to make solar, wind and other renewable energy equipment take energy to construct. It takes energy to make energy. Thus renewable energy can be used to manufacture renewable energy equipment. Solar energy is used to make solar collectors, for example. Local manufacturing of combustion air equipment adds to the local employment and tax base. It also reduces transportation cost and helps dispose of recycled materials. The invented device is a collection of renewable energy systems, wind, solar, hydropower, geothermal, biomass and potentially tidal energy. Each is focused on making combustion air for a fossil fuel burner. Each is focused on making air hotter, more pressurized, and moving at a higher velocity, 24 hours a day, year round. The key is to make the air via the most economical approach.
It is proposed that a graduated system be developed, where each module feeds to the other module. Proposed are modules of fixed size and shape, which are “picked and chosen”. For example, greenhouses will pre-warm the air that is blown into solar ponds (of salt water), or the greenhouses can pre-warm air to heated “sandboxes” with glass across, or more efficient solar flat-plates. The warmer air is then blown into more expensive concentrating solar collectors, like line-focus or evacuated solar tubes with a vacuum. By pre-heating the air with lower cost solar collectors, it helps reduce the size, cost and mount of more expensive high temperature solar collectors. The pre-heating of air in a gradual manner, stage by stage, means air can be blown into “very expensive” solar furnaces from less expensive modules. Thus not as many “very expensive” solar furnaces need to be built.
These “very expensive” solar collectors can be of various types: towers with heliostats, parabolic dishes, line-focus solar troughs, and so on. These very large solar furnaces can float on a turntable of water, or air, or can rotate to face the sun on steel tracks. By pre-heating the air from one system to another, whichever is most economic, it allows for a cost effective total system.
Key is to capture as much of the sunlight usefully and efficiently as possible. When a solar system allows most of the sunlight to fall on the ground, it is wasteful of land area. When solar collectors only capture a portion of sunlight, it allows a lot of heat to escape. This will unnecessarily require more land area to do the same job. Achieving 8.50% to 90% capture of solar radiation is essential to reduce the land area necessary to do the same job.
Key to movement of combustion air would be blowers, impellers, and fans. These will necessarily have to use solar, wind, geothermal or biomass energy. (Some fossil fuels can be used to keep a constant pressure, such as from a biodiesel powered blower.) The invented device proposes compressor modules of various types, perhaps 10 feet by 100 feet each in land area. Wind turbines can drive an electric blower. When the wind blows, the combustion air is blown and compressed. Solar photovoltaics can also power an electric blower. Solar heat can, also, boil a fluid like freon to drive a turbine. Stirling cycle engines can capture heat from biomass to drive a fan. Alternatively, hydropower or geothermal or biomass can also power a blower. Each of the 100 ft by 100 ft land area modules would have their own compressor/blower/fan. Thus a greenhouse would have a biomass compressor module, which then blows the air into a solar sand box collector, for example. The solar pond module would have a wind-powered compressor, which blows the air into a flat-panel module. The thermal powered compressor could use solar heat to boil a working fluid, like alcohol, steam, ammonia or freon to drive a turbine. Each step of the way, various compressor modules blow and compress the air. Each renewable energy module has it's own compressor. The downstream lower cost modules pre-heat the air for more expensive upstream modules.
It is proposed that the pipes be sized so that the airflow rate will be about 100 cubic feet per minute per module. As the air is heated and compressed, the air has more “enthalpy” (Enthalpy being defined as the total of all energy: compression, heat, velocity, water vapor and oxygen). At cold startup, the air will necessarily move slowly, but as the system warms, the air moves faster, and is more slippery, or increases viscosity. Proposed is a system of greenhouses, sandboxes, solar ponds, flat-plates, evacuated tubes, line focusing parabolic trough solar collectors, point focusing parabolic dish solar collectors. Each step of the way, the air is made hotter and more compressed. Each module has it's own compressor module, sucking the air from the downstream module and blowing and compressing the air to the upstream module. Each compressor module can have a flywheel attached to the blower/fan/impeller, thus allowing for storage of energy in the form of a rotating flywheel. When solar or wind energy is not available for the blower/fan/impeller, the flywheel will move the air.
The entire system of modules has considerable amount of thermal mass. It will take a considerable amount of time and also solar energy to make the entire system of pipes and energy collectors “hot”. This is referred to as “startup energy”. However, once hot, the modules will stay hot, even at nighttime or winter. By integrating hydropower, wind energy and geothermal or biomass, it guarantees that the combustion air will be delivered to the fossil fuel power plant, 24 hours out of the day, 7 days out of the week, year round. Wind energy tends to be very available during storms and during nights, exactly when solar energy isn't available. Hydropower turbines can make combustion air during periods when solar or wind energy isn't available. Geothermal or biomass energy, if available, can supplement. By going to multiple sources of renewable energy, and by integrating a large thermal mass, it will guarantee that combustion air will remain available on demand, 24 hours a day, year round, even during storms and at nighttime.
Each solar farm will be a compilation of several sub-modules. The goal is to generate air at 750 F degrees, 10 atmospheres, and at 100 cubic feet per second per module. These pipes would range in size from one-inch diameter to one-foot in diameter. The solar farms would then collectively compress air into long distance transmission pipes. The transmission system would further compress and move air, perhaps upwards to 1000 cubic feet per second. The transmission pipes would be heavily insulated and be of larger diameter. Larger compression blowers/fans/impellers (powered by renewable energy) would suck and compress. The transmission pipes are not dissimilar in function to pumping water. For example, to pipe combustion air over a mountain, electric blowers/fans/impellers would push the combustion air uphill over the mountain. As the combustion air flows downhill, turbines would recover the downward kinetic energy. The downhill side recovers the energy in the form of electricity, and the upside gets the energy. Thus the downhill side helps “pump” the uphill side. This process is not unlike what is done today for pumping water over mountains.
At the end of the transmission pipes, the combustion air is then utilized. It then can supplement the heat load of a coal burning power plant, a §as burning power plant, smelter or an oil refinery, or for other industrial heat. It can alternatively, be placed under streets and sidewalks for use by commercial or residential users. Retrofitting each fossil fuel burner will require re-engineering, but can be done. The non-radioactive portion of a nuclear power plant can be converted to use hot and compressed air to make steam for a turbine. Heat exchangers can be moved around so as to use the combustion air. Oil refineries can have a special piping system installed for the combustion air.
Once at the site where combustion air is used, there are tricks of the trade to make the air more hot and compressed. For example, one turbine could be attached to a second turbine. The first turbine compresses the air into the firebox, while the second turbine recovers the energy from the exhaust of the firebox. One turbine drives the other. This is not unlike how aircraft air conditioning systems work. The added pressure “squeezes” the hot air, making it more compressed and thus hotter. It is not unlike the principle of the hydraulic ram, where down flowing water is used to pump some water uphill. Other tricks of the trade can be invented on using the combustion air. For example, at coal burning power plant, existing coal carrying tubes can be converted to combustion air. A pair of tubes can be aimed at each other, where two flows of the combustion air collide with each other. The trapped coal is then ignited and atomized. The coal burning power plant firebox is converted to a “positive pressure” firebox, instead of the now common practice of being a “negative pressure” firebox. An energy recovery turbine at the exhaust of the firebox can recover some of the kinetic energy of the air, thus powering the compressors. Another trick to the trade is metals can be pre-heated for a smelter, or oil pre-heated for an oil refinery. Each of these applications will require further engineering, and some testing, but can be done. Hot air is very useful, especially if compressed.
It is an object to heat air with solar energy.
It is an object to compress the air with solar energy.
It is an object to add moisture to the air for better heat transfer from greenhouses.
It is an object to add oxygen to the air, so as to aid combustion, from greenhouses.
It is an object to heat air from wind energy.
It is an object to compress air with wind energy.
It is an object to manufacture hot air from a hot geologic formation.
It is an object to use a rotating compressor and an energy recovery turbine to move air through the hot geologic formation.
It is an object to pipe hot air for combustion via an insulating pipe system to a fossil fuel burner firebox.
It is an object to manufacture hot air for combustion from hydropower.
It is an object to use a hydropower turbine to drive a compressor to blow air for combustion.
It is an object to use a hydropower turbine to power a generator to heat an electric element to heat air for combustion.
It is an object to pump salt/alkaline water to the surface to create evaporation ponds.
It is an object to use evaporation ponds to increase local rainfall, so as to drive hydropower turbines to make combustion air.
It is an object to use solar distillation to increase the amount of local water.
It is an object to drive hydropower turbines, and to provide water for greenhouses, from solar distillation.
It is an object to burn biomass to create hot air for combustion.
It is an object to pipe heated combustion air long distance from biomass burning.
It is an object to move air at high velocity in a piping system.
It is an object to heavily insulate the pipes, so as to keep air hot.
It is an object to use hot and compressed and high velocity air so as to aid combustion of fossil fuels.
It is an object to collect hot and compressed and high velocity air, and place into a system of long distance transmission pipes.
It is an object to heavily insulate the pipes and bury them in dry soil, so as to keep pipes hot.
It is an object to use solar, wind, and other renewable energies to blow and compress combustion air over long distances.
It is an object to reduce fuel consumption in a firebox by pre-heating combustion air.
It is an object to reduce air pollution and reduce carbon dioxide emissions from combustion of fossil fuels.
It is an object to store thermal heat in thermal mass, so as to provide hot and compressed and high velocity air 24 hours a day, 7 days a week, year round; even during night or winter storms.
It is an object to help finance the construction of the energy “farms” by integrating “dual economics”, where for example, greenhouses make food, while making heated combustion air, solar ponds make distilled water while making heated combustion air, or for example, solar flat plates collectors can be the roof of live-able space.
The foregoing objects can be achieved by developing a system of modules, each tailored for the most economical method of manufacturing hot combustion air.
The foregoing objects can be achieved by assembling modules into farms, each designed to pre-heat for another module.
It is an object to use combustion air at a coal burning power plant, gas cogeneration plant, oil refinery, or for industrial uses like smelting metals.
It is an object to use combustion air for residential applications and commercial applications, like hot water heaters, furnaces, clothes and food dryers, wood stoves or other appliances.
It is an object to create a new underground public utility, like underground gas, electric, fiber-optic, or water utilities.
It is an object to create a similar system for residential and commercial buildings.
It is an object to convert existing household appliances like natural gas hot water heaters, gas dryers, furnaces, etc to use pre-heated combustion air made from renewable energy.
It is an object to use the thermal mass embedded in pipes to store solar heat for combustion-air.
It is an object to provide combustion air 24 hours a day, year round.
It is an object to preheat, compress and blow air into a firebox using fossil fuel, with the air made from renewable energy sources.