This is my solar water heater, cost about $200 and took a week to build at my okely-dokely pace.
I sweated (soldered) all the piping with 99% silver solder, 42 connections and not one leak. My next collector will have more tubes for more heat capacity. This was February and did it in my living room, plus it is very hard to run a torch in direct sunlight because you can't see the flame tip.
I used a maul and emt pipe to form 6" wide roof flashing which will cover the copper tubes. I just screwed a pair of 1x3s to a backer board leaving a 5/8" gap and commenced to smash a radius in it. Note: before pounding like a jack hammer remove any nearby nic-naks from your shelves, not that I have any. OK maybe a few Wild Turkey decanters.
I lined the 4'x8' box with 3 strips 20" wide flashing then installed the copper grid and covered with the extruded (smashed) fins and used aluminum pop rivets to hold in place, then painted with flat black BBQ paint. Note: I did smear a light coat of silicone in the fins before setting the copper in hopes to reduce any galvanic reactions that may occur betwixt the dissimilar metals.
I then covered it with UV protected poly carbonate using two lengths of bowed pipe to hold it away from the inside grid. The poly carbonate is very lightweight but 20 times stronger than fiberglass and also hail resistant. $36 for the two pieces used here. I laid a thick bead of silicon around the edges of the wood frame and allowed it to dry for two days before putting the poly panel on, this makes a water proof seal and will disassemble easily for maintenance.
Here it is sitting on my temporary rocket test stand, this 4' x 8' panel is only 4 inches thick. Note my uncompleted siding and roof projects - I can never seem to stay on task nor rake the leaves - but when you get an idea you must act or its gone.
Back view and a glimpse of the polyisocyanate insulation, yes it may sound like a poison but it is the best foam board money can buy. Not only is it high temperature and water resistant but also has a high R value for it's thickness - one inch is R7.
This single panel will make all the hot water I need in a day for washing and cleaning, 3+ more of these will provide the hot water antifreeze mix needed to heat my new cabin with a hydronic floor system. My testing was done in early March when 28F outside, starting with 50F well water I made 125F hot water inside of 3 hours, 125F is too hot for a shower so mixing with cold water i brought it down to 110F which is perfect for me and got a free ten minute shower. It did cost 2/10ths of a cent to run the pump for 3 hours but later that will be solar too.
Side note: a water heater tank in the house will very seldom go below 80F in a weeks time, so as described above starting with 50F water would be rare if at all, once heated the recovery will be much faster.
Of course not every day will be sunny here so a four foot square super insulated tank will hold all the hot water produced until needed, the tank should hold a weeks supply for me if the sun didn't shine in that period.
That pretty much covers it in a nutshell, any questions?
I sweated (soldered) all the piping with 99% silver solder, 42 connections and not one leak. My next collector will have more tubes for more heat capacity. This was February and did it in my living room, plus it is very hard to run a torch in direct sunlight because you can't see the flame tip.
I used a maul and emt pipe to form 6" wide roof flashing which will cover the copper tubes. I just screwed a pair of 1x3s to a backer board leaving a 5/8" gap and commenced to smash a radius in it. Note: before pounding like a jack hammer remove any nearby nic-naks from your shelves, not that I have any. OK maybe a few Wild Turkey decanters.
I lined the 4'x8' box with 3 strips 20" wide flashing then installed the copper grid and covered with the extruded (smashed) fins and used aluminum pop rivets to hold in place, then painted with flat black BBQ paint. Note: I did smear a light coat of silicone in the fins before setting the copper in hopes to reduce any galvanic reactions that may occur betwixt the dissimilar metals.
I then covered it with UV protected poly carbonate using two lengths of bowed pipe to hold it away from the inside grid. The poly carbonate is very lightweight but 20 times stronger than fiberglass and also hail resistant. $36 for the two pieces used here. I laid a thick bead of silicon around the edges of the wood frame and allowed it to dry for two days before putting the poly panel on, this makes a water proof seal and will disassemble easily for maintenance.
Here it is sitting on my temporary rocket test stand, this 4' x 8' panel is only 4 inches thick. Note my uncompleted siding and roof projects - I can never seem to stay on task nor rake the leaves - but when you get an idea you must act or its gone.
Back view and a glimpse of the polyisocyanate insulation, yes it may sound like a poison but it is the best foam board money can buy. Not only is it high temperature and water resistant but also has a high R value for it's thickness - one inch is R7.
This single panel will make all the hot water I need in a day for washing and cleaning, 3+ more of these will provide the hot water antifreeze mix needed to heat my new cabin with a hydronic floor system. My testing was done in early March when 28F outside, starting with 50F well water I made 125F hot water inside of 3 hours, 125F is too hot for a shower so mixing with cold water i brought it down to 110F which is perfect for me and got a free ten minute shower. It did cost 2/10ths of a cent to run the pump for 3 hours but later that will be solar too.
Side note: a water heater tank in the house will very seldom go below 80F in a weeks time, so as described above starting with 50F water would be rare if at all, once heated the recovery will be much faster.
Of course not every day will be sunny here so a four foot square super insulated tank will hold all the hot water produced until needed, the tank should hold a weeks supply for me if the sun didn't shine in that period.
That pretty much covers it in a nutshell, any questions?
That is incredible! 
