Glass, Acrylic or Polycarbonate?

One nagging question I had was weather it made sense to use glass over the panel, because I know from training in UV bonding technology that Lexan (AKA polycarbonate) absorbs just about 100% of the sun's UV rays.  What good would it do to go to all the trouble to build a solar heater if the transparent covering blocks some of the solar radiation? 

The chart at right from Wikipedia shows that even if we loose 100% of the UV we are still going to gain the vast majority of the energy in the sunlight.   Fair enough.  So, the plan will be to use whatever transparent material we find will fit the heater, and if we lose the UV spectrum it's not a huge loss.

Welcome to Father & Sun

Hey, I'm Scott and I'm a nerd. Not your normal, run of the mill nerd,  No, I'm the special type of nerd that enjoys learning and experimenting about all sorts of things.  Usually my projects center around something semi-useful, but the process involves learning new skills and best of all, new tools! 

A few nights back I was watching videos on Youtube and among them was one on a Harbor Freight photovoltaic solar panel kit, and something about it really intrigued me.  That one video led to another, then another, then another until I was convinced that I had our next big adventure settled: We're building a solar furnace.

I have three awesome resources from the start:  My dad, my son and my son-in-law.
More about the junior players later.  Let me introduce you to my dad.

My dad is an Engineer, a retired Air Force Colonel, a skilled home craftsman and a nerd!  Best of all he has been interested in solar power for years.  Back in 1976 when I was a young teen we lived in a home outside of Dayton, Ohio that my folks had built that had passive solar elements.  In 1981 my family left me in Dayton and moved to Littleton, CO where dad had active solar panels installed on the roof.  Dad knew that he wasn't going to be able to have easy access to the panels on the roof, and there really wasn't an affordable tracking system in those days, so in true nerd-style he did a study of past utility bills and determined that even though most people mounted their panels to capture the Winter sun, he determined that in his household (with THREE women) the warmer months consumed more water as well as more energy.  He theorized that because of sweaty Summer activities they were bathing more often and at higher temperatures. 

I knew this was the kind of insight that I needed in this journey, so I gave Dad a call today to let him know what I was thinking.

After a 10 minute conversation I was able to confirm some of my thinking and felt that it would be a great idea to blog about what I learn from him.

Moving forward watch for post titles with the word "DAD", or search the term Dad to find his wisdom.