This video show how a Fresnel Lens can be used to generate heat in water for a pool. It also illustrates the inability to heat water only. and the need for a dark target. The heat sink used in this video falls short of being a true dark object but the green color looked cool.
Is it possible to set something like that up so it’s not too dangerous to keep on? The lens & area between it and the pot are caged off – say running along the top of a high wall in a walled garden. Even if there’s a tap trickling water into the pot all of the time, so hot water trickles out over fill level to a metal pipe, I suppose you can’t rely on the tap not spilling out for any unexpected reason. Is there a material for this pot? If it’s spilling without touching, the pipe could be O.K.
I’m guessing that Fresnel lenses must present a great opportunity for heating swimming pools – by the “boil water in a pot” method that Greenp.s. shows in a video.
I mean a highly organised method, with a pump, a secure pot (that’s not going to disintegrate or burn if the system breaks down) dispelling hot water through a pipe every minute or so & taking in new water. Would the lens size requirement for winter (for the same size pot) be too big home pool, say New York?
The Fresnel lens would have to be significantly larger than the pool to warm the pool. A lens doesn’t increase the amount of heat, it concentrates it from a large area to a small area, so to heat a pool more than the open sun, you would need to increase the amount of sun hitting it, not concentrate a smaller amount of sunlight. If a pool has 10k square inch surface a 200 square inch Fresnel lens hitting it isn’t going to do squat.
Yes, Archimedes used mirrors to torch units (so the story goes) he also died in that battle, and his side lost. It would be great for torture though. (See articles about the Spanish Inquisition)
Lasers are the closest thing. Lenses or dishes with the sun would basically be impossible as all a target would have to do is either be mirrored, reflective white, or stay out of the focal point.
When using parabolic shapes to create a focal point, instead of going to the trouble of lining it with the mylar plastic, why not just paint the outside of it with regular mirror paint? Save time and effort.
hey ive been checking ure vids for awhile and thanks man they are inspiriing. so anyway how bout put the fresnel oto an a-coil or flat radiator panel (copper) and circulate a tube with another radiator into the water. add a solarpower pump to circulate the heated water and voila right? thats the idea thatsbeen in my headfor awhile
The only way this will work is to gather sunlight from another area outside of the pool perimeter, and add that to what is already hitting the pool. Concentrating the light that would hit the pool anyway will not raise the temperature. You need additional photons from somewhere else. The answer lies in the pool’s ability to absorb the energy from the light which is why the black mats Dan showed at the bottom of the pool are the least expensive and most efficient way to heat it.
You could you place a large piece of black builders plastic used in waterproofing concrete slabs. Very cheap, and lite to remove, attach a couple of pull ropes.
The same number of photons that normally hit the pool surface will not change because you put a fresnel lens over it. In fact, since a fresnel lens will dis-allow some of those photons to make it to the surface of the pool, there will be a net loss of energy to the pool. The frame of the lens, and the lens itself will either reflect light back out, or absorb it and release it to the air. The aquarium gained additional heat because the lens was larger, and the heat sink collected it.
For alanaldapierce- It would seem that the sun is still going to hit the rest of your pool like it normally does, but with a concentrated area of heat in one spot generating additional heat. I don’t believe you need a lense larger than your pool to have this work.
The lens heats things up by increasing the sunlight an object receives.
You can only heat a pool with the lens if the lens is actually BIGGER THAN THE POOL. Otherwise you’re just redistributing the sunlight, while leaving the net power the pool is receiving the same.
Of course you could make a net gain if you rigged the lens so its shadow falls outside the pool and it’s focus falsl inside, but then it wouldn’t be normal to the sun making it ineffective.
What if you put like a dark food coloring to the water. Would that work?
RAINBOW POWER!
Just admit you Failed to boil that water… you Failed.
if you want a warm pool, paint it black or use a black liner.
Is it possible to set something like that up so it’s not too dangerous to keep on? The lens & area between it and the pot are caged off – say running along the top of a high wall in a walled garden. Even if there’s a tap trickling water into the pot all of the time, so hot water trickles out over fill level to a metal pipe, I suppose you can’t rely on the tap not spilling out for any unexpected reason. Is there a material for this pot? If it’s spilling without touching, the pipe could be O.K.
I’m guessing that Fresnel lenses must present a great opportunity for heating swimming pools – by the “boil water in a pot” method that Greenp.s. shows in a video.
I mean a highly organised method, with a pump, a secure pot (that’s not going to disintegrate or burn if the system breaks down) dispelling hot water through a pipe every minute or so & taking in new water. Would the lens size requirement for winter (for the same size pot) be too big home pool, say New York?
The Fresnel lens would have to be significantly larger than the pool to warm the pool. A lens doesn’t increase the amount of heat, it concentrates it from a large area to a small area, so to heat a pool more than the open sun, you would need to increase the amount of sun hitting it, not concentrate a smaller amount of sunlight. If a pool has 10k square inch surface a 200 square inch Fresnel lens hitting it isn’t going to do squat.
Yes, Archimedes used mirrors to torch units (so the story goes) he also died in that battle, and his side lost. It would be great for torture though. (See articles about the Spanish Inquisition)
Archimedes did it…. Greeks are millenia in front…
Lasers are the closest thing. Lenses or dishes with the sun would basically be impossible as all a target would have to do is either be mirrored, reflective white, or stay out of the focal point.
God I hope they don’t use light as weapons that would be painful.
Awesome! I love science videos! We will probably be dependent on the sun someday or geothermal, but all energy sources have their pros and cons. 5/5
It’s so… PRETTY!!!
iv been telling people this for years with the black matts at the bottom of the pool im glade people are starting to wake up and realise..
you made a video of boiling water. why is it featured?
When using parabolic shapes to create a focal point, instead of going to the trouble of lining it with the mylar plastic, why not just paint the outside of it with regular mirror paint? Save time and effort.
Very good idea. It could be coupled or added to this concept.
watch?v=tE3QnqlnVOY
Thank you for the comment.
hey ive been checking ure vids for awhile and thanks man they are inspiriing. so anyway how bout put the fresnel oto an a-coil or flat radiator panel (copper) and circulate a tube with another radiator into the water. add a solarpower pump to circulate the heated water and voila right? thats the idea thatsbeen in my headfor awhile
put some bleu ink in it .. beleave me works good.. something to absorb the light
and radiation.
you do not understand the concept of conservation of energy/matter
The only way this will work is to gather sunlight from another area outside of the pool perimeter, and add that to what is already hitting the pool. Concentrating the light that would hit the pool anyway will not raise the temperature. You need additional photons from somewhere else. The answer lies in the pool’s ability to absorb the energy from the light which is why the black mats Dan showed at the bottom of the pool are the least expensive and most efficient way to heat it.
You could you place a large piece of black builders plastic used in waterproofing concrete slabs. Very cheap, and lite to remove, attach a couple of pull ropes.
The same number of photons that normally hit the pool surface will not change because you put a fresnel lens over it. In fact, since a fresnel lens will dis-allow some of those photons to make it to the surface of the pool, there will be a net loss of energy to the pool. The frame of the lens, and the lens itself will either reflect light back out, or absorb it and release it to the air. The aquarium gained additional heat because the lens was larger, and the heat sink collected it.
For alanaldapierce- It would seem that the sun is still going to hit the rest of your pool like it normally does, but with a concentrated area of heat in one spot generating additional heat. I don’t believe you need a lense larger than your pool to have this work.
The lens heats things up by increasing the sunlight an object receives.
You can only heat a pool with the lens if the lens is actually BIGGER THAN THE POOL. Otherwise you’re just redistributing the sunlight, while leaving the net power the pool is receiving the same.
Of course you could make a net gain if you rigged the lens so its shadow falls outside the pool and it’s focus falsl inside, but then it wouldn’t be normal to the sun making it ineffective.
All this experimenting is moot.