Solar Hot Tub

[Marywhit]

I recently read that there is now a solar hot tub?  Has anyone heard about this?  It was a small story I read in Hanahou Magazine while flying back from Maui to Texas.  I can not remember the name of the article... something soak.

Anyway, our electric bill was through the roof last winter and we need to find another option.

Mary

[Waterbug]

  Unless you use your hot tub only when the sun is shining, the concept is rediculus.  Even then, the solar panels to heat water to 100 degrees and power the pumps, would cover your roof.  On cloudy days, when you feel the need to feel a bit of summer/relaxation, there would be no solar power.  In other words, it is a gimic that would cost more than it would save in energy costs, unless you are in Arizona or New Mexico.

[Waterbug]

I found your article here:

http://www.hanahou.com/pages/magazine.asp?MagazineID=&Action=DrawArticle&ArticleID=1006

It is obviously intended to be used in Hawaii, where the sun always shines and the snow never falls.
  Raising water temperature 10 degrees above ambient doesn't take much solar power.  Raising water temperature 70 or 100 degrees above ambient is a different story.

[Chas]

I have years of experience with solar, and there is NO WAY I would put a non-glazed (open) collector on a tub. Doing so will run the tub into the range of 80 to 90 degrees (F) so you will have to kick in the heater to bring it the rest of the way. Personally, I want my tub hot (102F) at all times, so I don't know if there would be any real savings - I would first have to run a much bigger pump to move the water to the roof and back, and then add some heat during long chilly spells. We don't get "cold spells" this close to the ocean, so note that I said "chilly." 

Glazed panels are pricey, and need to be cleaned regularly. They work great, but by time you pay for the cost of the extra pump, you may not have a net savings.

I know - HotSpring tubs ARE knows for energy efficiency, so maybe others will benefit from solar. I have put several on wood tubs  - glazed and open. The glazed units can keep the tub at 102 all the time, the open units just keep it nice and warm, and a gas heater runs it up the last ten degrees or so.