If we all did what we need to do....(though I don't think it'll happen in my lifetime. The power companies and their shareholders have way too much to lose for starters.).
- Gas would not be a power option. All electricity would be generated via solar panels/wind power/other methods scientists might devise and we'll have to stop warming up our houses and instead do what our ancestors did - insulate ourselves, with layers. Almost all houses will have to have some kind of solar panel or wind turbine or other alternative (electro-magnetism??).
- We'd all be pretty much vegetarians if not vegans most of the time with very small amounts of animal or synthetic protein, maybe on feast days, and maybe eggs from chickens we'd keep ourselves or communally. Everything would be grown locally, within maybe 10 to 20 miles at most. There'll be some kind of levy on goods transported from further afield. We'd have fewer food choices but what we had would be healthier and more seasonal. Strawberries would taste like strawberries again instead of just watery mush and satsumas would be a seasonal winter treat. We'd all grow a lot more of our own food and bartering skills/resources would be a lot more common. Money would lose a lot of its appeal.
- Everyone would cycle or walk everywhere, and what motorised vehicles were left would be hybrids/hydrogen fuel cell (or whatever new technologies scientists come up with). People would think a lot more about whether their journeys were really necessary. Public transport would be vastly improved and when people did need to hire a car for long journeys car sharing would be more common and cars would be much more fuel-economic. Those gas-guzzling four-exhaust monsters you sometimes see would be crushed and melted down to make something useful. Air travel would have to be cut to an absolute minimum. I don't cycle but I love the thought of a world where tricycles would be more common, and we had decent bike lanes; on a trip to Holland I thought their idea of having the cycle lanes inside the actual pavement, not at the edge of the road, was a brilliant one. I have never understood why we are so grudging towards cyclists in the UK, and as a driver I am always worried I'm not giving cyclists enough clearance when I pass.
Video conferencing will become much more common, as will working from home/co-worker spaces. With the technology we have now, there is no reason in many cases why people have to cram themselves onto a tube train or equivalent, hurtle through dark tunnels, and emerge into an office coop where they then spend the rest of the day trying to ignore what's going on around them in an effort to actually get some work done. Remote working vacancies are slowly starting to increase in the USA, which means it will happen here before too long. As always, we'll be slower to adopt and adapt.
- More things would be delivered rather than people adopting shopping as a hobby. This is pretty much in full swing, if you look at Amazon, box deliveries, Tescos and the like.
- Plastic won't disappear - it can't, in the short-term - if you don't believe me, just look around your home and whatever you're using to read this on. But with any luck recyclable/recycled plastic will become a lot more common. And gradually other materials will replace it - probably ceramics, bamboo, metal, glass, reclaimed wood, hemp (if the government ever work out how to generate money from that last one effectively).
- People will be a lot more self-sufficient and try to mend things rather than just nipping out to the shops and buying a new one. Manufacturers might have to take a serious look at their built-in obsolescence.
- Depending on where you live, water will either have to be recycled in the same way it is on the Space Station, or we will have to work out some kind of water purification system. Hydroponic gardening is likely to become more common, especially where space is limited.
- If the floods continue we might need to start looking at some of the models in the Netherlands and other low-lying countries where electricity sockets are not put at skirting board level or on the floor, but half-way up the wall and some houses are on a type of stilt.
- Education will change. Instead of teaching kids about the wives of Henry VIII and making them read Shakespeare until they're blue in the face, it will need to be more skills-based. How do you grow things? How do you mend things? What herbs can you safely use when you have a cold? What do you do when things go wrong? I'm not saying there shouldn't be space for things like English literature and art and music, but some of the National Curriculum subjects and their guidelines out there have me practically weeping with how archaic they are now. (English Literature, which used to be one of my favourite subjects, being one. And meanwhile, past primary school, useful skills like growing things and home economics don't seem to be taught much.)
10. Fast fashion and fast consumption would have to come to an end; spinning and weaving wool (for example, or other fibres, again, like bamboo or hemp or even nettles and other plants) would become popular again, and when clothes were outgrown they'd be cut down or let out or shared. People would learn to cobble again, like my dad did for our shoes when I was little. You only took them to the cobbler when you couldn't mend them yourself any more.
10. And the elephant in the room - population. The choice is, the Earth's human population continues to grow and grow and grow with no thought as to whether we have the resources to support it, and the standard of living gets worse; or a conscious decision is made, globally, that everyone has to stop having so many children and the standard of living remains okay. And then you come up against the fact that developing countries, quite understandably, would like a slice of the rather lovely materialistic life it's been possible for some of us to enjoy in the west these last few decades. I don't think there's an easy answer on that one.
Off at a slight tangent, there are masses of science fiction books and films out there that, while they might be fiction, have plenty to say on the subject - Logan's Run, The Hunger Games, Firefly/Serenity and Make Room, Make Room being just a handful. I sincerely hope the future will, in the long term, look more positive, with people being much more nature-focused and living in smaller communities and being much more caring of those around them if they want to survive, but in the interim I don't think it's going to be much fun.