Solar panel to heat hot water cylinder.

[ladydukes]

Hello all.
we are moving and cannot afford to much to upgrade anything and was wondering if I could somehow attach a solar panel to the existing copper tank. we are linking a wood burner to it for winter heat & hot water. it is all ready connected to a back burning fire but will swap that.
We wanted something for the times when don't want light the fire. we do have an immersion coil but was thinking they may cost to much to use for hot water all summer.

please note we do not want solar hot water that is a completely different thing and to much cost. we also don't want the solar panel to power anything in the house or "feed in" or to heat the central heating.

what size panel would we need to heat a standard size tank for a 3 bed house and how much ( a ball park figure would be o, as need to know if it's do-able)