Patent Application
20200386970
This specification discloses and claims subject matter disclosed in prior application Ser. No. 16/140,161, filed on Sep. 24, 2018 [2018 Sep. 24]. The subject matter is directed to an invention that is independent and distinct from that claimed in the prior application, and names the inventor named in the prior application.
The primary field of application is to reduce Global Warming. This method is related to lighter-than-air vehicles.
Anthropogenic climate change threatens humanity. Heat and heat-absorbing Green House Gases (GHG) released into the atmosphere are raising Earth's surface temperature. Reference [1] reports that Earth's atmosphere is retaining heat at a net rate of 2.29 Watts per square meter of the Earth's surface. Normalized to the disc area of Earth seen by the Sun, this gives 9.16 Watts per square meter. This is compared to the nominal value of 1350 Watts per square meter of solar energy falling on Earth's atmosphere. The prescribed remedies are controversial because they hinder economic growth or prevent the advancement of subsistence economies. Implementation if any will take a long time. Residents of islands and low-lying coastal areas are threatened by rising sea levels because of the polar ice caps melting. Extreme weather events are already attributed to climate change.
One way to control Global Warming is to reflect a part of the sunlight back into Space. Such a remedy has been proposed by several methods in prior art. These include reflectors or bubbles in Space [2-3], reflective particles or balloons released along with industrial exhaust and other aerosols [4-8], extracting carbon dioxide (CO2) from the atmosphere and ejecting purified air [9,10] and wind turbines pumping Antarctic sea-water to the ice-cap [11,12]. Ground-based tiltable reflectors have been proposed [13]. US national laboratory researchers [14,15] have proposed increasing the albedo of urban areas by mandating white paint on roofs and sidewalks. The above shows that the Prior Art consists of difficult methods that have proved to be impractical, harmful and ineffective. Their long-term effects are not understood. They are not easy to remove once deployed. The above survey also illustrates the extreme measures that have been proposed, implying huge expense and strong and varied concerns. None has to-date been adopted on a large scale.
Prior application No. [Ser. No. 16/140,161] proposed and advanced a solution called the Glitter Belt. The solution is to float reflective sheets in the upper atmosphere. The deployment may be nominally at altitudes near 30,480 m (100,000 ft), using means that ensure that they will not sink below 18,288 m (60,000 ft, the edge of controlled airspace) in the night time. The reflectors are anticipated to be made of thin sheets with low areal density. They will have highly reflective upper surfaces, and the option of flat black lower surfaces. The former is to reflect sunlight in the daytime. The latter is to absorb radiation from Earth at night, so that most of it will then be transmitted by conduction to the upper surface and radiated out into Space. The concept is shown in
The subject of the present invention is an implementation of the aforementioned Glitter Belt where the reflective sheet is supported in the atmosphere by means of aerostatic lift. One example of this implementation is shown in
It is obvious that helium could be used instead of hydrogen. Helium is generally denser and more expensive compared to hydrogen. Hydrogen is adequate when no humans are carried on the vehicle. Further implementations, for example, ones that combine this implementation with that claimed in the Prior application [Ser. No. 16/140,161] are also anticipated.
While prior work as shown, has anticipated the use of hydrogen and helium balloons, it did not show the way to alleviate a disadvantage of hydrogen. Hydrogen diffuses through the balloon shell. The present invention includes means of alleviating this problem. The means are to incorporate a double-layered thin sheet shell for each balloon and the rim. As claimed in Prior application [Ser. No. 16/140,161], a vacuum pump driven by solar power pulls hydrogen from the space between the two shells and pumps it back into the inner space. In this way the loss of hydrogen by leakage is reduced to negligible level where it no longer becomes the limiting factor on the longevity of the vehicle.
In the present invention, the method to implement one aspect of the Glitter Belt system is to support a reflective sheet using a set of hydrogen balloons. This is shown in
The aerostatically supported reflector concept avoids the need to provide continuous aerodynamic lift, and therefore minimizes the night-time glide requirement. As the sun sets the balloons will cool, so that the gas inside them will increase in density. As a result, balloon volume will decrease, so that the vehicle will come down to lower altitude.
Such altitude loss motion need not be entirely a vertical motion. The altitude loss can be minimized by tilting the sheet so that it glides edgewise through the night, generating aerodynamic lift using the sheet as a large lifting surface. This is anticipated by the fixed-wing aerodynamic implementation in the prior application Ser. No. 16/140,161.
The gliding motion described above can be used to change the position of the vehicle as needed to optimize position with respect to the sun for the next day.
The balloons can be used to hold the sheet in an attitude that is tilted to large angles. Such tilting can be used to maximize reflection of sunlight even where the sun is quite low on the horizon. An example of this is the case in summer over the Antarctic Circle.
Some concepts are anticipated to improve the effectiveness of the first deployed systems. The most urgent visible symptom of Climate Change is the breakup of the Antarctic Ice Shelves [16]. These are large sheets of ice formed by the flow from glaciers coming off the higher elevations of Antarctica. Large portions of these ice sheets are floating on the ocean. As ocean temperature increases the balance shifts between summer-time melting and winter ice accumulation. As a result the sheets become thinner and weaker. Fractures appear. Large chunks drop into the ocean and float away to warmer parts of the ocean, and melt. Their melting raises the mean sea level. Thus, the problem is not so much the heating of the Antarctic plateau, but the rise in the ocean temperature bordering Antarctica. By decreasing summer sunlight on the ocean at the coastline, the balance between summer melting and winter ice accumulation may be reduced enough to reverse the present trend. An array of reflectors located appropriately over the coastline of Antarctica in summer will assist in this process.
In prior art, Kawai [13] has suggested ground-based reflectors along the coast on the glacier edge to reduce solar this. However, the high installation cost and the dubious environmental acceptability of such reflectors are not addressed. Also such reflectors cannot be installed beyond the stable edge of the glacier or rock. In particular, they do not reduce sunlight falling on the sea ice bordering the coast.
The present invention offers a scalable, automatic-controlled and remotely deployed solution that is superior to installing ground based reflectors in Antarctica. The installation of a ring of such upper atmosphere reflector arrays around the polar circle is named the Polar Necklace. As the Antarctic summer ends, the reflectors can be drifted and redeployed to follow the summer Sun using the small solar-powered rotors.
Even in summer, the polar Sun is quite shallow, and hence reflectors must incline at a steep angle to be normal to sunlight. The Balloon Beanies are well suited to this problem, since the lift needed from the balloons is the same at any inclination.
The reflectors can be moved constantly to best reflect sunlight. Unlike birds that wait for late autumn and spring before undertaking long flights, the reflectors can be drifted slowly and continuously to track the midsummer Sun daily as the seasons change over the planet. The drift speed required is miniscule, well under 1 m/s according to calculations presented in [17] and [18]. The Balloon Beanies can be used for this purpose by using small solar-powered propellers during daytime, and an edgewise glide at night. This flight is in a manner that is superficially similar to that of a frisbee toy.
Unlike space-based concepts, the Glitter Belt can be deployed one at a time, brought down and individual elements can be replaced as required. Each swarm of sheets can be slowly and benignly directed to descend through the atmosphere, to touch down either on land or in water. Except for the sheets that may get damaged, most of the rest of the vehicles may be recovered.
The Glitter Belt invention referenced to Prior application [Ser. No. 16/140,161] is to place ultra-light reflector sheets, not in orbit in Space, but at the edge of the atmosphere. Above 24,000 meters (roughly 80,000 feet) altitude, the sky appears black to the unaided eye, from horizon to horizon. This is true even in bright sunlight. This is because there is not sufficient air to scatter the light and give the blue appearance that is seen from below.
The above-referenced sheets can be equipped with sufficient structure and means for automatic guidance, navigation and control, so that they can fly in autonomous mode with only minor supervision from ground-based controllers. Over most of the planet Earth, wind speeds and weather variations are small at such altitudes where the invention is to be flown in its usual application.
The advantages of the Glitter Belt concept compared to the Space-based reflectors of prior art, are obvious. The energy required to place the reflectors at the selected altitude is less than two parts in a million (2/1,000,000) of that required to place the same area of reflectors in Earth orbit in Space. On the other hand, objects that are placed in orbit require very little additional energy to stay in orbit for a long time, whereas vehicles in the atmosphere need power addition to counter winds and stay in position. However, sunlight provides plentiful and inexhaustible energy to power such vehicles. Unlike Space vehicles which incur high launch costs, the Balloon Beanie vehicles can be launched from the ground almost anywhere on a clear morning, to climb to the required altitude. They can be repositioned easily by means of small rotary propellers, compared to the high expenditure of energy required to change the orbital plane of a spacecraft. The aerostatically supported reflector vehicles can be launched one or severally at a time. They can be removed from flight when it is so required. Such removal can be accomplished with safe recovery. The vehicles can be launched again if desired.
Reflective sheets of aluminized Mylar, as an example, reflect nearly 100% of broadband sunlight. With the reflectors located at a nominal altitude, for instance near 30,480 meters (100,000 feet), almost all of the reflected radiation will exit permanently into Space. Higher or lower altitudes are also possible. In comparison, a ground-based reflector will only send about 50% of solar radiation back into Space, with most of the remaining 50% being absorbed in the lower atmosphere.
Because they avoid allowing sunlight to be absorbed through a round-trip through the atmosphere, high-altitude reflectors are roughly twice as effective per unit area as ground-based reflectors. They do not need permission from landowners. They can float above the oceans and icecaps as well. They are not affected by cloud cover and receive direct sunlight for more hours per day than ground-based reflectors. The ability to drift with the seasons to say under the summer sun, makes them more efficient than ground-based reflectors.
Several references below describe prior art and basic knowledge that are applied in the new use described in the present invention.
Solar-powered aircraft in general are described in References [19] and [20]. These generally show that sufficient solar power can be absorbed during the daytime to enable a heavier-than-air aircraft to stay aloft in the atmosphere using aerodynamic lift. Patent US 2016/0144969 A1 [Reference 19] describes a high-aspect ratio wing with vertical winglets and multiple electrically driven propellers. This is generally similar to the NASA Solar Pathfinder and its derivatives. More recent inventions from Airbus Industries describe newer versions of high-altitude, long-endurance aircraft that bear several similarities to the PathFinder concept, but still use energy storage means to survive the night-time gliding period. Unlike all of these prior art, the present invention does not have to use stored electrical energy to sustain night-time altitude because the aerostatic lift continues during the night.
U.S. Pat. No. 4,415,133A [Reference 20] describes a solar-powered aircraft. The idea of keeping the solar panels perpendicular to the Sun by flying the aircraft at a large bank angle is considered there. The Balloon Beanie example of the present invention renders banked flight unnecessary. The mass distribution can be changed to tilt the sheet to a different orientation when the balloon is static above a given location. Alternatively or complementarily, the gas pressure to the different balloons can be altered. This will change the volumes of the different balloons and thus the individual aerostatic lift of each This can assist in changing the orientation of the sheet. The cost and complexity of flying complex maneuvers to reflect more light, has to be traded against the cost of manufacturing and launching more sheets. In one implementation, the first vehicles may be equipped with more sophisticated controls to maximize effectiveness, while mass production of sheets and carrier vehicles is ramping up.
U.S. Pat. No. 3,452,464 [Reference 21] describes a reflective Mylar sheet. Patent US20140252156A1 [Reference 22] describes a High Altitude Aircraft, Aircraft Unit and Method for Operating an Aircraft Unit, generally similar to Reference [23] in design but incorporating thin Mylar sheets for covering the structure. U.S. Pat. No. 9,475,567B1 [Reference 24] describes a double-layered balloon for the purpose of reducing gas leakage. It does not anticipate placing a solar-powered pump to evacuate and re-use the gas from between the two layers, as is specified above and claimed in the present invention.
Technology that is relevant to the Glitter Belt architecture has been developed and presented by several researchers and inventors. References [24] and [25] describe the technology of solar sails. These promise to reduce the thickness and the areal density of the reflective sheets by orders of magnitude. Hence their future use is an obvious extension of the use of Mylar sheets used in one implementation of the present invention.
Reference [26] defines the International Standard Atmosphere, used in calculations for the present invention. Reference [27] describes the performance achieved with the NASA Pathfinder aircraft. Unlike the Pathfinder, the Balloon Beanie does not require auxiliary energy storage or other night-time power generation means.
References [28] and [29] describe engineering aspects of aircraft that are intended for long-endurance flight in the upper atmosphere, including the use of solar-powered airplanes. These aspects are mostly included in the design of the Pathfinder and related aircraft. Again, the need for auxiliary energy storage forces these aircraft to have significantly higher wing loading than the implementations of the Glitter Belt invention. In addition they require the carriage of concentrated loads such as fuel cells, which imposes additional requirements on the structural strength and thus the weight of these aircraft.
Reference [30] presents experience from communications with a high-altitude solar-powered vehicle. This shows that remote operation of such vehicles has been studied, and is feasible. References [31], [32] and [33] discuss technical aspects of flying several aircraft or birds in close formation. Such flight has been used since the large bomber formations of World War II to increase range, while aerobatic exhibitions demonstrate extremely close formation flight even at very high speeds. Thus it is clear that formation flight in swarms, and communication with high-altitude swarms, are both solvable problems. Reference [34] describes the properties of the material used to make high-altitude balloons in the 1960s.
Referring to
Solar-powered rotors around the periphery provide trim, counter winds, and allow the twice-a-year migration. Some energy storage may be added to provide emergency power at night. The issue of hydrogen leakage is addressed with a double-shell provided with an evacuation pump in between. The shell structure can be made with present materials, but future implementations may offer opportunities to use advanced ultralight materials such as Silica AeroGel. The reflective coated Mylar membrane of the balloons reduces the tilt needed to reflect evening, morning and polar summer sun. The size of the inner hydrogen-inflated shell can vary, constrained by the dimensions of the outer shell, so that the risk of bursting when exposed to direct sunlight is alleviated.
Various configurations are anticipated for the Balloon Beanie. The configuration shown in
As described above, the Glitter Belt invention presents a low-cost, scalable and reversible method and apparatus which can be deployed rapidly to reduce the rate at which the temperature of the Earth's atmosphere is rising. It reduces the solar irradiance to the atmosphere. It is anticipated that initial deployment tests using full-scale or small-scale models will establish the performance and effects of the invention, permitting rapid scaling up. It is understood that a large number of reflectors will be needed to significantly reduce the rate of atmospheric heat retention. High impact can be obtained early with concepts such as Polar Necklace, and summer-following sheet swarms. It is also anticipated that the reflector sheet systems may be combined with other uses, thereby improving their economic viability.
The Balloon Beanie invention as an implementation of the Glitter Belt invention proves that at least one near-term solution exists, for the problem of Global Climate Change. It is possible to reverse atmospheric heating back to desired levels. Such a large change will require a large number of reflectors, to be deployed, over a period of 1 or two decades, with the participation of many nations around the world. Unlike prior concepts, the Glitter Belt is not known to cause any adverse effects. All the deployed systems may be removed from high altitude and the material recovered on demand. These aspects may be verified by actual testing which can proceed during the initial phase before significant expenditure of time or financial resources. In these respects and others, the Glitter Belt invention provides advantages superior to those of any prior inventions.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16140161 | Sep 2018 | US |
| Child | 16855817 | US |
