Insulating a hot water tank

 We are building a parabolic solar hot water heater and would like some sugg=
estions to insulate our 60 gal. hot water tank.  We have been successful in=
 heating the water from 60 F to 155 F.  At this point we are using an alumi=
nized-foil type of "blanket", but it's a little expensive and doesn't reall=
y adhere very well to the tank wall.  We have seen some insulating foam on =
the market called "Great Stuff" and was wondering if this might be suitable=
 (or more suitable).  Our tank is a recycled 60 gal. painted, galvanized dr=
um originally used to ship fruit from Guadalajara to the northern border.

Any suggestions would be appreciated and have a great evening!  :)

 
l in heating the water from 60 F to 155 F.  At this point we are using an=
 aluminized-foil type of "blanket", but it's a little expensive and doesn't=
 really adhere very well to the tank wall.  We have seen some insulating =
foam on the market called "Great Stuff" and was wondering if this might be =
suitable (or more suitable).  Our tank is a recycled 60 gal. painted, gal=
vanized drum originally used to ship fruit from Guadalajara to the northern=
 border.

Try a spray on foam_ expanding foam material. Apply liberally to
external surface of tank to a depth of approx 60 - 70mm.  Make sure
the operation temp of the foam is with + 20deg. of your top temp
requriement.  Also choose a foam with a high uvalue.  Trim off excess
foam when hardened to provide a smooth ish surface 60 -70mm deep. If
you use a paper mache of newspaper / magazine material _ high celulose
content, and made with hot water.  Paint a touch of gummed glue on
finished surface of foam, then apply paper mache a few mm thick.
Alternatively you could use your foil over the foam insulate material
instead of the mache.
mike Fleming