25 Responses

1. The “steel pipe” is really copper.
   Big difference

2. very cool

3. Nice video and music…(and morse code)

4. @craftmatic2

   Ok crap, need to correct my numbers.

   The water from your tap is about 70f, not 40f, so that makes about a 30% difference. Still, this means you’d save around $630 per year.

   Additionally, since water from the tap is 70f, the solar heater can actually heat it ~30% faster than the calculation above. I just used 40f because that’s what he had in the video.

   It really depens on what the temperature is for your tap water. The colder it is the more heat you need…

5. @hermenutic

   The water heater probably ends up being the single most expensive thing in a house. If you replaced it with 12ft by 3feet of parabolic mirror like I said above, plus what you need to vaccuum seal it, you’d save like $900 per year in electricity bill savings.

6. @hermenutic
   If you had a parabolic trough mirror about a meter across the curve, by 3.6 meters long, and you had it focused on a copper pipe vaccum insulated, you should be able to heat 80 gallons of water from 40f to 140f during the 6 hours of optimum sun….This is based on rough calculations I did assuming 1/3rd of the solar flux is reflected by the earth’s atmosphere and 2/3rds would hit the mirror…

   It takes about 70560000 joules (19.6kw/hr) = like $2.55 electric bill.

7. this is exactly what we do and it has saved allot of money.

8. this heat-on-demand is the way to go. is that a copper pipe? what other metals can be used that would be safe for drinking?

9. great idea,but i think it will take people chainging there lifestyle slower to get them to like this stuff,how about turning your hot water off when not useing hot water and on 30 min befor u need hot water

10. Nice. But I can piss 9 gallons per hour. A parabolic reflector should be treated like a pistol. You need to carefully observe the background to limit collateral damage. A glass paperweight on the windowsill once set my girlfriend’s computer desk on fire.
    I was reloading the hummingbird feeder and saw a newspaper burst into flame. Luckily I had a 9 gallon fire extinguisher on me….

11. I see that this works with a small volume of water flow. I do not see how it will heat hot water for a family. I am favorably impressed with the ability to harvest the sun in this way.

    I would be interest in how long it takes to heat 80 gallons of water such as a household would use.

12. nice

13. amazing…what happens on a cloudy day?

14. woah 901 degrees at 2:34 .! wtf Dan.

15. this makes me wanna pee !!!!

16. I find it rather wierd how some peolpe need such hot water all the time. My tank is turned as low as it can go…and it still burns my hands.

17. I think the best solution to heating water is ditch the hot water tank altogether. Why heat water when it’s not being used? instead heat as it’s needed. They should start making those “hot water on demand” units cheaper. That’s the way to go. Also, make it law to have a “rain barrel” system in every home. Fed into the house by gravity and heating on demand.

18. I’d say give it “never”. It took me till I was 29 before I realized we’ll never see the light. It’s all clear to me now. That’s why gold is made expensive. Same as silver, copper, diamonds. All materials used for the best solar equipment. It must be the longest running conspiracy. And yet all of those cost the same. Nothing but labour. Until currency is gone…it’s a waste of time trying to make solar work for everybody…so for now and until money is gone..solar is for the rich

19. but what im trying to say is it doesn’t have to boil water to be effective. I understand your arguments for colder climate and agree with you – geothermal would be better. Wood burners are great and wood is sustainable so that makes sense but since we now have an air tax (carbon) and make people feel guilty about burning wood is no good. Current solar systems are a bit expensive for effect give it a few more years…

20. Truth is if we weren’t living in such a stupid era…we would be using wood to boil water when needed. Take away all that fucking packaging from products at the store. Fridges aren’t needed with underground cellars. It’s al bullshit. Solar only mildly helps people in northern climates…we’re lucky to even get 200watts per square meter here in the winter. Solar is for the rich and those in warmer climates.

21. I always wash clothing in cold…hot water is not neccessary at all. Baths only need to be luke warm. Hot water is also not needed for people to do dishes. Boiling water is only needed for drinking or cooking. Both of which are too expensive for someone living in a cold climate to achieve through solar. Try selling solar to a family making 30000 a year.

22. 100 degrees celsius is boiling point not 65 degrees. You shower and bathe and do dishes in cold water?
    If you have a storage cylinder then you are constantly keeping water hot by using electricity or gas, If you have instant gas then you can save money by not using gas so much.
    At a temperate climate of 20 degrees celsius then I heat water to 65. So using solar (not every day but still a significant proportion) I can acheive savings by preheating water in sun then refill cylinder

23. That’s boiling temp…that’s what I said. And besides that…the realization that we don’t need hot water on demand makes most solar heaters useless. The only thing hot water is need for is drinking…and that must be boiled…so a solar unit must work in a climate where temps go below -20c or else there’s no point.

24. – when water is stored in your home cylinder it only has to achieve 65 degrees celsius once every 24 hours to kill legionares bacteria. On top of this if you can supplement your home heater with something like this you are going to save yourself heats of money. Thats a huge benefit…

25. For more green power, see this:
    tinyurl(DOT)com/2wbb23j
    (loose the brackets and use a dot where it says DOT)