Solar boosted electric or electric boosted solar?

I've been looking at going solar for my hot water but it ain't easy.

All the flat panel systems (Solarheart etc) are expensive and I believe the resellers just add the rebates onto their list prices. Why not? :eek: But there are vacuum tube systems such as this
http://cgi.ebay.com.au/30-Tube-Sola...Appliances&hash=item3ca53df63d#ht_1883wt_1012
that are far cheaper and would remain so after rebates are taken into account.

If I go that way and forget rebates, is there a simple way to use a solar panel to boost my existing electric system either to heat the water in the jacket or by preheating the water being used?

Anyone with good/bad experiences?
 
Using vacuum tubes will require a pump for the life of the HWS . I don't like that.
Vacum tubes are more efficient in colder climates.

I did a heap of research and went with a closed circuit for my second solar HWS. Just make sure you get a marine grade steel storage tank.

Replacing a panel is expensive in a closed circuit but you can replace individual tubes in the vacuum type. If you have House insurance for storm damage then it wont be an issue .
The seals in the vacuum tubes are susceptible. be a little wary.
A heat pump throws out cold air which was my next choice over a closed circuit.House orientation was poor as well.
The tank is in a double garage but the cool air comes into the kitchen via the door to the garage and makes a big difference to keeping the house cool for longer. Almost like an air conditioner.
In Brisbane we need to use the electric heater for about 6 weeks a year. I notice your intended unit doesn't have one , but maybe you don't need one in your part of the world.

250 litre is too small for a family of 4 as it wont be full of hot water, only a portion of the water will be hot in my view.


CANT ANSWER THE CRUX OF YOUR QUESTION, SORRY
 
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there is a vacuum tube system with a 12w pv panel to drive a pump, the pump runs faster when there is more sun so the returned water has a farily constant heat
I want my next build to be ground source heat exchange for heating and cooling, total electrical input 145W, heat output 85KW
marvelous
 
The best I can add is that we had a solarhart on the roof at our last house but here we have a split system, I preferred the the solarhart on the roof. It seemed to stay hotter for longer and we hardly ever needed the booster. We are nowhere near as happy with the system we have now.
 
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