I am in favour of diversifying away from fossil fuels as a primary source energy generation, which is what we are doing.
Scotland produced enough power from renewables last year to meet around 96% of it's needs, so we are on the right track, but work needs to be done in terms of battery storage to make it possible for supply to meet demand consistently.
Interestingly, I read a white paper on battery tech around 2013 that set out the expected timelines for various renewable technologies to become commercially viable and they've been scarily accurate so far. Battery tech was predicted to have a breakthrough in relation to home storage around 2025 and were already seeing that coming through with things like Tesla's Power Wall and Genarc PWRcell.
There's also a lot of work being undertaken with relation to decarbonising heat with hydroge, which could help solve the heating issue if that becomes viable. SGN are about to begin a full scale trial of a hydrogen gas network made from 100% renewabes produced hydrogen in Scotland (called H100 if you care to look).
However, it's a transition not a switch over and will take time to get everything in place. We (as in humans not just Scotland) will probably never be able to fully stop using fossil fuels as oil and gas derived feedstock is a key part of hundreds, if not thousands, of intermediate and end-user goods. Hopefully carbon capture technology will also develop to the point that we can full scrub emissons from fossil fuel use, and again their is good work being undertaken with Direct Air Capture and Accelerated Weathering, but those are in their infancy so will likely take much longer to become commercially viable and not something we should be focusing on.
Oil & gas has never been the "main plank" for paying for independence. It's a lazy assumption people who don't want to look into it Scotland's natural and human assets make to convince themselves we're too stupid and poor to be a successful country on our own.
We're a small nation with a relative abundance of natural resources and world renowned industries. As I mentioned in a previous post we have 25% of all of Europe's offshore energy capacity, which is an unbelievably huge deal given the way the world is moving. Tidal power technology (breakthroughs expected around 2030 if memory serves) dropped off the Scottish coast could produce enough energy to make us Europe's Saudi Arabia (minus the human rights abuses hopefully) and Japan had just recently deployed a 100kW seabed turbine for trial, that if successful would be game changing. We also have a good reputation in tourism, food and drink, gaming (which is often and oddly overlooked seeing as the gaming industry is worth more than the film and music industries combined), renewables, electronics, textiles, and financial services (not the best but Edinburgh is ranked ahead of the likes of Madrid, Rome, Dublin, etc and only London is ahead of it in the UK). Put all that together and revenue from selling oil and gas would just be a welcome extra, but not fundamental to our success.
I'm always puzzled as to why people always use the oil question as a "gotcha" when it comes to Scottish independence, like do they not realise that there are countries out there who are successful who have very little, if any, oil and gas of their own i.e., Sweden, Switzerland, South Korea, France, Japan, etc?