Both Hunterston and Torness, the two Scottish nuclear power stations will still be operational in 2020, producing about 2GW with an uptime of about 90%. The SNP, if they're in charge in an independent Scotland (and they're a one-note political party in the main, independence being their focus) want these reactors decommissioned and replaced with... they're not sure but no nukes! Gas-burning CCGTs, probably although the North Sea gas fields are not what they used to be so fuel will probably have to be imported after a decade or two. There are still a few coal-fired plants around and several wind farms, a couple of GW dataplate output but some days they only produce a few dozen MW in total. Solar is a non-starter in a country where the sun is in the sky for six hours in the winter and it's usually cloudy then anyway. Hydro, about a GW of capacity but it can't run 100% of the time, just when there's been enough rain recently. Sea-floor turbines are being trialled at the moment, no track record on costs per MWh generated, maintenance overheads etc.
Fossil fuel will provide a lot of Scotland's electricity for the forseeable future especially if the nuclear plants are not replaced when they are either shut down by government fiat or they reach the end of their licence periods and can't be relicenced.
A major English offshore wind project recently didn't go ahead even with a price guarantee of about UKP 145 per MWh, or in US consumer terms about 24c per kWh wholesale to the grid suppliers -- that would be about 30c/kWh to consumers after grid supply costs and profit figures were added, about what the Green Germans are paying and double the price of French nuclear-generated electricity at the wall-socket. I can't see Scottish wind power being any cheaper especially with the extra backstop gas generation and storage needed to keep the lights on when the wind stops blowing.