I have a contractor renovating my one existing bathroom and while he was in the house working I thought it would be a good opportunity to replace my 15 yr old water heater which is currently in the kitchen.

What I was thinking of trying was purchasing a solar storage tank with electric back-up.  The electric would be my sole source for hot water until I could save up for the solar collectors and get a system installed.

Just hoping for some opinion on using the storage tank for a while without the solar.  Thanks.

Rheem, Rudd or Richmond Solaraid HE 80 Gal.  Exchanger is external to tank but well insulated.

The highest level of insulation I've seen is R17. Does anyone know of a higher level tank?

I believe the Marathon water heater has a higher R-Value.  It is guaranteed not to leak for the life of the home.  It does not require an anode rod since the tank is not metal.

It will work, just make sure you size it right, for the solar I mean.

It works better to have the solar tank in series with the tank with the heating element (or with a flash heater) otherwise on days that the sun is intermittent and the water is lukewarm you will be forced to be heating  the one tank up to the temperature you want.  By plumbing them in series the storage tank will act as a preheater and on the good days it will be so hot that the tank with the heating element won't have to kick in.  This will save a lot more energy than consolidating both in one tank.