Personally, I envision the energy mix in the future to be along the lines of:
40% nuclear (whichever kind of nuclear technology is used)
40% renewable (primarily solar and wind, with other novelties such as water, geothermal, biofuels to account for less than 5% of the overall mix)
20% coal/gas with carbon-capture and storage.
I can also see the typical household being able to generate around 10% of its own energy needs, have fuel cells that can store around 12 hours of energy, and have water recycling facilities that reduce a house's water demands by between 20 and 40%. I also wouldn't be surprised if most houses (particularly in the UK) switch from gas a means of heating, to elecricity.
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Of course, this would all be immediately binned if and when we crack fusion.
