www.greenpowerscience.com This is a very simple trough design you can run a 100′ trough for less than 0.
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25 Responses to PARABOLIC TROUGH REFLECTOR SOLAR WATER HEATER GREEN POWER
Wrapping plastic around the PVC pipe should be the last step. Use outdoor double sided carpet tape to secure the clear plastic sheeting to the PVC pipe. This will hold in the heat.
I have some random sections of 6 inch sewer pipe. I can do the math on cutting into 1/3 slices. Using this with 3/4 ID iron pipe, how far from the bottom should I place the 3/4 water pipe. I just quick rigged somthing with tin foil (on a cloudy day) and it looks like approx 3 inches from foil to bottom of iron pipe will have the solar pin point in the center of the water pipe. Do I want to focus for center? A blank slate here.
@teknotoast The reflectivity isn’t stronger at one point of the trough than another so it would make sense for it to be an equal distance rather than sunk in further.
Mind that focussing mirrors, like parabolic ones, only work for direct radiation, thus straight from facing the Sun. This applies in very dry and/or cloudless climates, like on the poles, hot deserts and the top of high mountains. In the tempered, rather cloudy climate zones, most of the solar radiation is diffuse (coming from all directions). In South Sweden f. ex, it is 80% diffuse and almost 100% in tropical rainforest climates – only flat solar panels can be effective there!
Thermospecialist
October 17, 2011 at 4:24 pm Reply
A practical use for a solar trough might be as the heat source for wood gasification. No open fire or flame needed to gasify the wood in the gasifier, which would make gasification even cheaper & require less wood overall.
Wood gas can fuel a generator for home power. Generator could recharge a battery bank while powering an electric burner beneath an alcohol still for fuel alcohol. BAM, home power & transportation needs covered without oil or coal. Sun would provide bulk of energy required for
Though I was Harrison Ford for a moment in Raiders from the Lost Ark about to be sawn in half in the camera shot from inside the pipe while being cut . Creative camera work Dan.
It was pointed out, but a radius is not a parabola. The focal point (Pf) of a radius, such as this pipe, is 1/2 the inside radius. Placing the ctr of your pipe exactly at the ctr of the Pf will cause the light from the reflector to hit the pipe evenly. Placing it below the Pf like yours is will cause it to aim at the top half of the pipe from behind. Placing ctr of the pipe above the Pf just shy of the pipe’s radius will cause the light to concentrate in 1 line along the bottom of the pipe.
subsonykexorcist
October 17, 2011 at 5:52 pm Reply
Something important to know is that PVC dust is carcinogenic when it is airborne and inhaled, so make sure you are wearing sufficient breathing protection when you cut it.
subsonykexorcist
October 17, 2011 at 6:06 pm Reply
Are there advantages to using larger diameter pipe? 12″ dia. vs. 6″ dia., or is the cost difference not worth the increase?I ask as I have larger dia. pipe avail for free…
I love your enthusiasm. You have done many of the experiments that I have only given thought to. I would like to see some more videos where you show how to take the experiments one step further and make a practical solution where they can be used in every day living. 10 stars buddy. Great work.
Benny
Wrapping plastic around the PVC pipe should be the last step. Use outdoor double sided carpet tape to secure the clear plastic sheeting to the PVC pipe. This will hold in the heat.
ucjb2
October 17, 2011 at 10:32 am
Wrapping plastic around the PVC pipe should be the last step
ucjb2
October 17, 2011 at 10:32 am
so this will actually heat the water (in full sun) as it travels through the pipe at pressure? (how much pressure?)
so, actually it operates like a tankless water heater?
marz3335
October 17, 2011 at 10:59 am
how did you mount that pivot on your table saw? drill it?
marz3335
October 17, 2011 at 11:13 am
“shape as a parabolic…” easy to say, isn’t it?
em84009
October 17, 2011 at 11:54 am
Is it worth the effort to get a true parabolic surface as opposed to a hemicircular surface?
SecularMentat
October 17, 2011 at 11:56 am
@GREENPOWERSCIENCE
You can buy this Type from Solarfocus.
They sell it as CPC and you can find it here: solarfocus.at
FriedlMichael
October 17, 2011 at 12:02 pm
wonder if mylar would work as a reflective material with something to hold it up.
Unclesamslair
October 17, 2011 at 12:56 pm
Dan,
I have some random sections of 6 inch sewer pipe. I can do the math on cutting into 1/3 slices. Using this with 3/4 ID iron pipe, how far from the bottom should I place the 3/4 water pipe. I just quick rigged somthing with tin foil (on a cloudy day) and it looks like approx 3 inches from foil to bottom of iron pipe will have the solar pin point in the center of the water pipe. Do I want to focus for center? A blank slate here.
28bull
October 17, 2011 at 1:09 pm
5:19 thats what she said
bladerockss
October 17, 2011 at 1:22 pm
You have no idea what you are talking about…
PaperHeartFor2
October 17, 2011 at 1:37 pm
A good focal point calculator mscir.tripod.com/parabola/
Nicholsp02
October 17, 2011 at 2:00 pm
and what’s material you use to make mirrors?
Bekzat95kz
October 17, 2011 at 2:23 pm
@teknotoast The reflectivity isn’t stronger at one point of the trough than another so it would make sense for it to be an equal distance rather than sunk in further.
mocatz187
October 17, 2011 at 2:55 pm
@mocatz187 no, no it’s not.
teknotoast
October 17, 2011 at 3:17 pm
pipe is too low in trough.
mocatz187
October 17, 2011 at 3:22 pm
thanks dan ilove your videos
696969640
October 17, 2011 at 4:18 pm
Mind that focussing mirrors, like parabolic ones, only work for direct radiation, thus straight from facing the Sun. This applies in very dry and/or cloudless climates, like on the poles, hot deserts and the top of high mountains. In the tempered, rather cloudy climate zones, most of the solar radiation is diffuse (coming from all directions). In South Sweden f. ex, it is 80% diffuse and almost 100% in tropical rainforest climates – only flat solar panels can be effective there!
Thermospecialist
October 17, 2011 at 4:24 pm
A practical use for a solar trough might be as the heat source for wood gasification. No open fire or flame needed to gasify the wood in the gasifier, which would make gasification even cheaper & require less wood overall.
Wood gas can fuel a generator for home power. Generator could recharge a battery bank while powering an electric burner beneath an alcohol still for fuel alcohol. BAM, home power & transportation needs covered without oil or coal. Sun would provide bulk of energy required for
mangyscavenger
October 17, 2011 at 4:30 pm
Though I was Harrison Ford for a moment in Raiders from the Lost Ark about to be sawn in half in the camera shot from inside the pipe while being cut . Creative camera work Dan.
trespire
October 17, 2011 at 5:08 pm
It was pointed out, but a radius is not a parabola. The focal point (Pf) of a radius, such as this pipe, is 1/2 the inside radius. Placing the ctr of your pipe exactly at the ctr of the Pf will cause the light from the reflector to hit the pipe evenly. Placing it below the Pf like yours is will cause it to aim at the top half of the pipe from behind. Placing ctr of the pipe above the Pf just shy of the pipe’s radius will cause the light to concentrate in 1 line along the bottom of the pipe.
subsonykexorcist
October 17, 2011 at 5:52 pm
Something important to know is that PVC dust is carcinogenic when it is airborne and inhaled, so make sure you are wearing sufficient breathing protection when you cut it.
subsonykexorcist
October 17, 2011 at 6:06 pm
Are there advantages to using larger diameter pipe? 12″ dia. vs. 6″ dia., or is the cost difference not worth the increase?I ask as I have larger dia. pipe avail for free…
robherrdotcom
October 17, 2011 at 7:04 pm
I love your enthusiasm. You have done many of the experiments that I have only given thought to. I would like to see some more videos where you show how to take the experiments one step further and make a practical solution where they can be used in every day living. 10 stars buddy. Great work.
Benny
ynnebbenny
October 17, 2011 at 7:51 pm
For all the people asking for reflective film check out “3M Solar Mirror Film 1100”
euxle
October 17, 2011 at 8:31 pm