Is there such a beast available that combines an electric producing
solar panel with water heating? I'm guessing having a water circuit
carrying the heat from the presumably high temperature solar panels
might serve to pre-heat water before sending it through the boiler or
WHY and increase the life-span of the panel?
Or does the generation/removal of electricity significantly reduce the
temperature of the big flat black surface?

I'm also guessing the installation of solar panels on a roof reduces the
heat transferred into the roof/loft space in the house by a fair amount?

There must be a reason why solar panels don't seem to come with a water
heating circuit?

Just a thought..

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