My dad used to say we’d all be eating petroleum in the future. At first I thought that was just another nutty thing and add it to the list. My dad said a lot of nutty things. His point at the time was not some cosmic, Arthur C. Clarke-like prediction, however. It was simply connecting the dots: it took energy (primarily in the form of fossil fuels) not only to farm our crops but to process them and ultimately to store and transport the foodstuffs they created. Our food is very energy-intensive. That energy once came from human and animal muscles, now it comes from machines. Those machines need oil and our farms need oil-produced products like fertilizers and pesticides as well as fuel for trucks and tractors and whatnot. In a sense we were already eating oil.
Dad didn’t know much about chemistry, but he knew that hydrocarbons and carbohydrates were pretty close on the chemical spectrum. He thought it should be easy to convert fossil fuels directly into something edible. It’s not a bad notion. You can’t get stuff much more organic than petroleum, coal, or natural gas. They were once living things after all: oil comes from marine plankton and coal from tropical plants. Dad knew that hydrocarbon resources were wildly abundant. It was the 1970s and we’d had the Oil Embargo and gas rationing but he knew that was just politics and economics. There was—and still is—plenty of oil out there. We aren’t going to run out. We’ve plucked the low-hanging fruit, to be sure, but the tree is certainly not stripped.
So Dad’s idea was that it would make more sense to synthesize food directly from the stuff in the ground rather than go to all the trouble and energy expenditure to process the oil into fuel and other agro-chemicals and then grow food, process it and transport and store it for sale. Nutty, I know, but not that improbable. We may have to get used to some rather strange food sources in the future. I suspect that wild-caught salmon might get replaced by jellyfish extract at some point, at least for the hoi polloi. The one-percenters won’t lack for anything of course, but the rest of humanity will likely be eating an interesting variety of synthetic amalgamations. I’m sure they’ll be quite nutritious and exhibit a variety of flavors and textures so we’ll get by. “Real” food will be a luxury item. It will be a difficult transition at first as we have very romantic notions about food. Ultimately hunger will win out and we will learn and adapt. Meat, for example, will likely be grown in vats instead of on animals. At some point we won’t know the difference.
All these things will require energy, and maybe the energy sources will be solar or nuclear rather than oil, so maybe we won’t eat petroleum after all. In fact, I think Dad had it backwards. We’ll be going the other way and converting carbohydrates to hydrocarbons. Or at least converting them to fuels. We already get ethanol from fermentation and mix that into our gasoline. The source of that ethanol is mostly corn (maize) and other mass-produced crops like sugarcane. A lot of waste from crop harvesting (stalks, leaves, and such) could be carbohydrate sources as well. Advances in bio-engineering will allow us to ramp up production and we’ll soon have vats of microbes belching out organic fuels for our cars and trucks and boats and planes.
Before the Industrial Revolution every society was carbohydrate-based. Food supplied the energy for humanity and their beasts of burden. The great transition of the last two hundred years has been to hydrocarbon-based societies. Coal came first, then crude oil and natural gas, and the machines took over. I suspect we’ll need a lot more of that stuff as our population grows, and we’ll have to exploit all the other energy resources like nuclear and renewables, as well as carbohydrate-based fuels. In fact, it’s all on the table. Until we come up with some amazing things like fusion or hydrogen fuel cells that can be deployed effectively we have to use what we already have. We know that it works. Yes, we have some serious environmental consequences from our energy choices, but we need the energy or our way of life goes kaput.
What I should say is we need cheap, abundant energy. Everything else depends on that. We squabble a lot over politics and “issues” and other mostly dumb things. We’d be better off thinking about the things we HAVE to do something about, namely, how to fuel the world and our lives within that world. Physics is a cruel master. There are no shortcuts. We have to have lots of available energy so we can grow and prosper as a civilization. I’m not sure where it’s all coming from, so I suspect you don’t either. I guess we’d better get to work on that.