- Green Technology
Solar energy by water lens
Solar energy utilization
The sun broadcasts vast energy on Earth. Authoritative sources would agree the power involved may be more than enough to supply the needs of humanity for generations to come.Mankind may have enough power from the sun for as long as the specie wants earthly residence.
Schemes to harness the sun's energy so far need some complex technologies that have to be developed over many years, sometimes over decades. The development of such technologies may be accelerated, though likely through some desperate conditions only.
Some desperate conditions may have occurred contributing to the availabilty of many complex technologies now so that systems utilizing the sun's energy may be successfully developed or had been developed. Such systems as of this writing though may be quite expensive or are not or are not popular enough to be promising solutions for current energy problems.
A possible scheme that may not need too complex technologies is to mobilize somehow the great mass of humanity who think they are under desperate financial comditions. Quite a large percentage of humanity including this writer may believe they belong to this mass.
Implementing the type of currency system as described in the article "Energy and global poverty integrated aid" (at section "Other readings online" below) could be a double-acting solution that may help in these two of mankin's pressing concerns: power hunger and population's hunger.
Water, the stuff that cradled and is so essential to LIFE, is a principal subject matter of that writing and of this one too. Hail to WATER!
Solar radiation compressor
A kind of compression that happen in some current devises routinely makes solar radiation usable. Devices operating with that process may pack onto a relatively small target space (sometimes called "focus") the highly energized hot radiation falling on a larger receiving area of the device (or compressor).
Radiation compression processes may be classified through the manner it compresses radiation: reflective radiation compression or refractive radiation compression.
In the refractive process, a deflection of passage occur to radiation traversing the transparent thicknessof the compressor's refractor whose density differ with surroundings (ie: surrounding air). The deflection occurs on entry and/or exit as the radiation traverses the boundary between refractor and surroundings, a movement that is directed towards the target's position.
Radiation exiting the dense substance of a thick refractor may have some undesirable energy losses with corresponding reduction in overall efficiency for the refractive radiation compressor.
Radiation in a reflective compressor on the other hand is bounced around outside of dense substances reversing direction at least once or more than once in longer routes that nevertheless may result to good overall compressor efficiency.
In a common reflective compressor configuration, incoming radiation is initially compressed by reflection from a concave parabolic mirror towards a much smaller intermediate bouncer mirror, to ultimately reach the target space as energetic compressed radiation.
Because of the simplicity of the simplicity of radiation pathway and associated hardware for refractive radiation compression processes, devices that work on the principle are popular components in solar energy utilization systems for individuals or entities of moderate or lesser means.
Refractive radiation compressor
The refractor of a refractive radiation compressor is also commonly called "lens". It may have either of two distinctive crosswise profiles that makes the device thick or relatively thin: convex lens profile or the thinner fresnel lens profile.
Flatwise,slanted surfaces circling the lens center induces radiation elements moving on parallel paths to bend and close rank towards a smaller space some distance from the lens face.
In a fresnel lens, the slanted surfaces are seen as a number of concentric ring surfaces slanted at varying angles. In a convex lens, the whole face bulges in the middle and curves thin to the rim. In both cases the angle for the surface slant is greater at the edges and lessens towards the center.
In shape flat-wise the fresnel lens may often be cut as square or have other polygonal shape. The convex lens' more familiar shape is round. Inexpensive fresnel lenses made of plastic may be used for solar radiation compression.
Water and refractive radiation compression
Water is a transparent, liquid stuff; usually inexpensive and available easily, it may also be used instead of glass or similar solid materials in radiation refraction systems (the resulting refractor or lens may be called a "water lens").
Without solidity, liquid water may naturally be moulded to refracting convex form by gravitation and use of some transparent and pliant material (like maybe an inexpensive sheet of plastic).
The exit passage for radiation in a water lens may have two deflective directions: some angular divergence or spreading in the boundary between water and its more dense moulder (say plastic sheet), then greater angular convergence in the boundary between moulder and surrounding air (more details regarding direction of deflection is given in a later section titled "Simplified analogy for refractive compression of radiation").
The focus of a water lens moulded only through gravitation without some form of correcting means may not be as sharp as that of artificial glass lenses, but its intensity may be good enough for some purposes.
Mostly liquid, a water lens on Earth (as well as on other prospective masses orbiting the sun) may have the limitation of being usable only if positioned flatwise so that a volume of compressed solar radiation is produced somewhere below. It may also have limited time utility if used in Earth based solar power facilities.
Despite those serious limitations water lenses have at least two very desirable characterestics and potentialities that may be nonexistent or hardly possible with current solid lenses:
>>>=====> Easy availability for almost anyone anywhere of the main component refracting material (water).
>>>=====> Large or very large water lenses may easily be constructed and/or repaired (may not be as difficult as grinding large blocks of glass, assuming the task feasible).
Possible common applications for simple water lens
The structure and usage of a water lens basically is simple enough to be easily understood, made and utilized by individuals of varied cultures. A solar radiation compressor, simply constructed with a simple lens could have popular application at least as foodstuff cooker or as water heater, especially for people with very limited or without income.
A very simple solar radiation compressor may be constructed using broad, transparent and pliant material like plastic sheet or else cellophane secured at its edges between elevated supports (any available support in the surroundings may do) through some fasteners or else heavy weights then filled up with water on top to the level its slacking middle portion can hold.
Weighed down by water, the underlying moulder should bulge downward into a convex surface. Adusting the tension of moulder and/or fastening sufficiently in proportion to the weight of water moulded may deflect radiation to satisfactory intensity at the target compression space (the adjustment may need some experimentation).
The water moulder's geopmetric shape could just be a regular square fastened on its 4 sides, or if a more roundish shape is preferred a regular octagon with 8 equal sides may be made by cutting off appropriate sizes from the 4 corners of the square.
Simplified analogy for refractive compression of radiation
An analogous view for the bending of radiation may be related to a supposedly wavelike form of radiation. This kind of form may cause the deflection of a radiation element crossing a slanted boundary between transparent substances of different densities.
With the sun as source, radiation elements on parallel paths bend or deflect at different angles when passing differently angled boundaries of two substances with different densities, to travel converging paths to smaller space some distance from the refractor, compressing radiation and energizing the space.
Considering that the target is struck by radiation deflected from all around above, radiation in its elementary composition be more analogous to spiral or helix instead of wavelike. Radiation may have wavelike movement to explain some known observations, though may have spiral elements. The composition of a rope may also have similarity to radiation - rope fibers are wound as spiral, though the rope itself may be undulated to wavelike form.
A radiation element in the form of either spiral or wave would likely have different drags in two opposing sides when crossing the boundary between two substances of different densities and may swerve in the direction of the denser substance because of greater restriction in that side (the so called "wave length" possibly shortens and bends on the side with denser substance while stretching on the opposite side).
This directional change in radiation movement may be likened to a tendency of wheeled vehicles to swerve when passing obliquely from muddy to clear section of road. Wheels at the muddy section may have more resisting drag and could cause the vehicle to somewhat swing around in the direction of the muddy part if not controlled.
The bending of radiation element because of passage in an angled boundary between two different substances may easily be imagined through a convex lens profile. If the bulge is at the bottom surface, radiation exiting the lower slant deflects towards the lens axis (the deflection would still be towards the axis if the bulge is at the top surface).
Water lens other possibilities
Water lenses that are more sophisticated and/or very much larger conceivably may also be constructed and utilized by organizational entities that have the resources and means to construct them.
With large enough lenses the water moulder may be fixed with some structural arrangement, internal or otherwise, that can support the moulder as well as align surfaces so that refracted radiation may be deflected to better compression or focus.
The thinner fresnel lens profile rather than the convex lens profile may be more advantageous in the very large water lenses.