What if the world had no oil? As modern civilization’s primary energy source, its absence would profoundly affect our way of life, opening up fascinating possibilities for worldbuilding very different yet plausible speculative fiction settings, including science fiction and alternate history. In this post we will explore alternative pathways for a world that is not only without oil, but without any fossil fuels at all.
Wood: The Original Fuel
Prior to the age of fossil fuels, wood was the primary energy source, its combustion providing light and heat for settings as diverse as a bedroom, a blacksmith’s forge, and a hunter’s campsite. The primary source of firewood was (and still is) trees, thus as populations grew deforestation became a major environmental problem even well before recent centuries; not coincidentally the most developed countries are currently in the midst of reforestation now that demand for wood products has lessened and less land is needed for agriculture (improvements in yield per acre have outpaced population growth).
Wood is sometimes cited as a renewable resource, and it is, but forests can sustainably support only a small fraction of the world’s energy needs, even assuming a pre-industrial level of population and energy usage. The implications of this reality for worldbuilders is that any planet that uses wood as their energy source for any remotely modern technology level, especially for industrialization, will need to have (relative to Earth) a small population, an abundance of woodland (ideally made up of fast-growing large trees), or a combination of both, or they will be in serious trouble in the near future.
Could wood work as an industrial fuel? Steam engines, particularly in the early stages of their development, sometimes used wood as fuel, but coal became dominant because of its higher energy density. Coal has a longer heritage as a fuel source than many would think, as coal was used to heat baths as far back as the Roman era in northern European regions where it was abundant and easily accessible. While wood will not work as well as coal, and thus will lead to more expensive energy and lower standards of living, there is ample reason to think it could support at least the early stages of industrialization. The fact that charcoal (a wood product) is capable of powering cars, as was proven in some areas during the Second World War, suggests it could fuel (some of) the later stages as well.
Beyond Wood Without Fossil Fuels
So wood, while likely capable of serving as an industrial fuel, nevertheless has limited and poor capabilities compared to any of the fossil fuels. What other possibilities exist to fuel an industrial revolution then? In a realistic world without fossil fuels there is a way that may be considered cheating, but would be among the likelier possibilities: biofuels. Even if there are no fossil fuel deposits hydrocarbons can be refined from crops, as sugar cane and corn ethanol prove today. While biofuels (with a few exceptions) aren’t competitive in our world without subsidies, in the absence of fossil-fuel alternatives they may be the best available.
The Ford Model T was what we would now call “flex-fuel” and Henry Ford himself tried (unsuccessfully) to promote the use of ethanol. Vegetable oil too can be used as fuel, and these fuels can be easily produced with even Neolithic-level technology, as the invention of alcoholic beverages indicate (the active ingredient there is ethanol). Early cars in remote areas such as Appalachia were sometimes run on alcohol, which was already being manufactured in home distilleries for other purposes.
A key metric to consider when comparing fuels is the specific energy, the amount of energy released per unit of mass. This is not to be confused with energy density, which is energy per unit of volume. Energy density is important in settings where minimizing the weight and size of the engine is important, such as cars and airplanes; specific energy, on the other hand, is more important in settings where the engine’s size and weight is unimportant, such as a power plant.
Wood has a specific energy of 16 megajoules per kilogram. Coal ranges from 24 to 33, and ethanol weighs in at 26. Methanol, another fuel in the alcohol family of compounds, rates 20 on the same scale. Ammonia, a somewhat more exotic fuel, rates 18. Biodiesel weighs in at 41. For comparison, gasoline rates 46, much higher than any of these alternative fuels except biodiesel (which is beyond early-industrial technology). Natural gas (methane) rates 55, considerably higher than gasoline; only its low density (gas as opposed to liquid) has kept it from being the primary energy source in real life for as long as it has, because larger tanks are required and it’s more expensive to handle. As these obstacles are overcome, natural gas will become more commonplace due to its higher specific energy. Hydrogen is a more extreme version of natural gas in these respects, being even less dense but yielding 142 megajoules per kilogram. The same technological progression that promotes natural gas will also promote hydrogen eventually. Hydrogen has the highest specific energy of any chemical fuel, so it is the ultimate as far as chemical fuels go.
Nuclear fuels, however, are on an entirely different level. The specific energy of uranium is a whopping 80 620 000 megajoules per kilogram, half a million times as powerful as hydrogen. Thorium rates 79 420 000, plutonium 2 239 000, and even a (by nuclear standards) weak fuel like tritium (a radioactive isotope of hydrogen) still rates 583 529. Why isn’t everything nuclear already, then? Well, it happens that while uranium has a million times the energy of coal, it also costs about a million times as much per unit mass to build the infrastructure needed to extract that energy, thus the cost comes to about the same; though that cost could be reduced substantially by reducing needless regulation and red tape (perhaps one or two orders of magnitude), current technology and engineering are the primary obstacles to it reaching full strength (rather than fundamental physical obstacles). Technology advancing over time will only make nuclear reactors cheaper, and the inherent power advantage will gradually dominate the cost calculation. Thus in the long-term future nuclear energy should become the dominant power source due to what will become unmatched affordability per unit of energy.
Of course, advanced nuclear reactors don’t help an industrial-revolution-era society that doesn’t have the technology to build such a thing, so what fuel would they use? In my view, wood would likely transition over to biofuels such as ethanol during the early industrial era of a world without fossil fuels. As near as I can discern there simply wouldn’t be any better fuel source available to such a civilization. Past this it gets murkier, since the second industrial revolution level of technology (late 19th century) introduces electric power plants into the picture.
An Electric Revolution
Generating electricity is somewhat different from raw combustion or nuclear chain reactions, since any method of driving a turbine can be employed. This is most obvious in the case of wind turbines and hydroelectric dams. These will present themselves as new energy sources to a biofuel-based early industrial civilization, freeing them from dependence on crops along with their enormous land-take. Undoubtedly the advent of electricity would change the balance of power in ways that, in a properly constructed world, may be geopolitically profound.
This didn’t really happen in our world because electric power plants were mainly powered by coal, the same fuel source vehicle engines used. Here it’s much more likely to be different. Against low-energy-density biofuels, hydroelectric plants in particular may be able to outcompete other sources of energy in affordability, thus attracting industrial development, and subsequently population and wealth, to good river dam sites. Biofuel and electric cars will dominate, with electric outcompeting biofuel wherever electricity is available. This is actually fairly similar to what happened with cars in real life before the advent of cheap gasoline; in a world without fossil fuels this era will last much longer.
Water power will very likely be well-established even before the electric revolution, since the textile mills that were the site of the earliest stages of the industrial revolution in real life were usually water-powered. Mechanical water wheels will likely remain more competitive than in real life, thus making the conceptual leap to hydroelectric even easier than it was in our world.
Another energy source useful for electricity is geothermal power, which was first commercially produced in Italy as early as 1911. In a world where electricity, as opposed to solid or liquid fuel, demand is much higher and hydroelectric and biofuels constitute the competition, geothermal energy will be far more developed. This will attract economic development in such a world to good geothermal energy sites, much like the river dam sites.
Other possible energy sources include tidal power, where electric turbines are turned by water moving with the tides. Tidal mills did exist before the industrial revolution and there were prototype plants in the early 20th century. Wave power plants also existed as prototypes in this same era. Neither got much development until later in the 20th century, but it is possible that they will get much more attention in a world where biofuel is more expensive than hydro or geothermal electricity, and perhaps more expensive than marine electricity as well. Still, if I had to guess I’d say marine power will proliferate a bit later than geothermal, but likely will be greatly important.
So our fossil-fuel-less civilization will jumpstart industrialization with biofuels and then switch to hydro-, geothermal, and marine-generated electricity a few generations later, which may be much cheaper and more abundant. Since these were the first non-carbon electricity sources to be employed in real life it seems likely such a civilization would start with them. We now have a civilization where those lucky enough to be near a river dam site, ageothermal hot spot, or a stormy sea have industry based on cheap electricity, and those elsewhere have industry based on expensive biofuels. How would this setup evolve as technology progressed?
From Biofuel to Synthetic Fuel
With electricity being cheaper than biofuel in our hypothetical world, regions just outside the power grids attached to the great dams, geothermal springs, or rugged coastlines will do everything feasible to link up to these grids, furthering electric cars and marginalizing biofuel cars in more and more areas of the world. Trains, which in this world would originally have used biofuels, would undoubtedly electrify much earlier than in real life. Since the range of an electric train is far greater than an electric car, trains may retain an advantage over automobiles in long-distance passenger travel for much longer.
As technology advances and electricity generation becomes more efficient, the cost will come down. This will also lower the cost of producing fuels synthetically, which in a world without fossil fuels will likely become the dominant method over time. All chemical fuels are molecules made up of particular elements, which can be refined from raw materials and recombined into the appropriate molecules using electric heat or (much more efficiently) direct geothermal heat. For instance, carbon dioxide and water, both of which are found in air in reasonable quantities, break down into carbon, hydrogen, and oxygen, which can be combined to make any hydrocarbon or alcohol fuel.
This will give a civilization without fossil fuels the ability to manufacture as much hydrocarbon fuel as they want without needing to rely on fuel crops. This will enable them to have all the same fuels we use today, though at modern electricity prices the cost of fuels will be much higher. At modern prices, synthetic gasoline from nuclear energy would cost around $6 per gallon according to a 2008 Los Alamos study. It’s a safe assumption that cheaper electricity will reduce the price proportionally, and vice versa. As technology advances synthetic methane and ultimately hydrogen will predominate, for the reasons detailed previously.
When a world without fossil fuels discovers nuclear energy, it will offer an energy source that will be, with some development, at least as cheap and effective as conventional energy, but which can be deployed without regard to geography, which in this world would be revolutionary. Regions of such a world that are distant from good dam sites, coastlines, or geothermal sites would be keenly interested in nuclear power. It seems very likely that a civilization without fossil fuels would, all other things being equal, embrace nuclear power to a greater extent than we did in real life. Once nuclear comes into its own all liquid and gaseous fuels would be made synthetically with nuclear heat, the cost of such fuels would come down, and energy would become steadily cheaper. This is much the same as will likely happen in our future, so they will be on the same track as us at this point. The primary difference is that with the absence of a pre-nuclear oil age the advent of nuclear energy would be experienced as more revolutionary than it was in real life.
When Sails meet Reactors
Before nuclear technology dominates, though, the geographic confinement of cheap energy compared to real life would have interesting implications. Most cargo has long been transported by ships, because it is the cheapest method per unit weight; this will hold true on any planet. These were sailing ships up until the industrial revolution, when they were replaced by coal-fired steamships for most applications. Without coal, biofuel will be the best available fuel source, and that has much less energy density. Even against coal, sail power still was the most efficient power source on the clipper routes, only truly being eclipsed in the 20th century with the rise of oil-based fuels. This close-run competition in the 19th century suggests to me that sails will remain dominant as long as biofuel is the best available.
Thus for the entirety of the equivalent of the 19th century in a world without fossil fuels sails will dominate the seas. The Age of Sail will still be going strong past such a world’s equivalent of 1900. If you’re trying to worldbuild a plausible setting where the technology is more modern and industrial but you still want sails, the kind of setting we’re exploring in this post is your golden ticket. Only the advent of synthetic fuels could seriously challenge sailing’s economic advantage, and even then they likely won’t achieve oil’s economic advantage until this world’s equivalent later in the 20th century. By then for a craft as large as a cargo ship nuclear reactors would likely be at least as economical as hydrocarbon fuels; aircraft carriers and icebreakers, which are comparable to cruise ships, ocean liners, and cargo ships in size, use nuclear reactors today in real life economically and effectively.
This would likely happen sometime in this world’s equivalent of the late 20th century, with the advent of nuclear ships marking the end of the age of sail. This direct transition from sail power to nuclear power might seem jarring to us, but consider that in real life the nuclear navy appeared only several decades after the last clipper ships were operating. In such a world sailing would remain viable until the equivalent of the late 20th century for large ships, with nuclearization moving down the size scale over the decades as technology advances (nuclear reactors are much more efficient at larger scales). This implies, if you look at the advancement between each generation of small reactors, that small ships may still be sail-powered into the equivalent of the early 21st century!
Zeppelins Fill the Sky
With sailing ships persisting in economic roles into the 21st century level of technology, any air travelers may have interesting sights to see should they overfly a seaport. What sort of aerial vehicles would predominate in a world without fossil fuels?
In real life air travel is relatively sensitive to energy density, so the impact from the unavailability of cheap jet fuel will be harsh, since there will likely be no good substitute. Biofuels can service an airplane (airplanes have flown even with solar panels, a much worse energy source) but performance will be much lower due to the lower energy density. Thus speeds will be slower, planes smaller, and costs higher from the invention of the airplane through the end of the biofuel era. The advent of synthetic fuels will enable energy densities similar to real life to be accessed for the first time, but will be much more expensive than real life fuels, at least at first.
Of course, many forget that the airplane isn’t the only form of aircraft: the airship is the airplane’s great historic rival, and in this world without fossil fuels the much greater fuel efficiency of the airship will prevail in bringing affordable and well-furnished air travel to the masses. Costs may well be the same per trip as modern aircraft, the one great disadvantage being the much longer travel times (roughly five times as long). A world without fossil fuels provides a plausible way for worldbuilders to have airships thrive all the way through their world’s equivalent of the 20th century, and perhaps beyond.
Like sea travel, air travel will likely be nuclearized by the equivalent of the 21st century, though unlike sailing ships the form of zeppelins wouldn’t change much if they became nuclear, aside from becoming larger in size. Large airships were already approaching the sort of masses where nuclear makes sense in the 1930s; the building of ever-larger airships means the largest ones by the late 20th century will adopt nuclear power not too long after the ship-size reactors become available. Nuclear power works better at larger scale and at large scale provides more power-to-weight ratio than conventional fuels can, so this will enable by the time this world reaches modern technology levels the creation of massive airships that would dwarf the Hindenburg.
Nuclear airplanes, if Cold War-era studies are anything to go by, will be enabled by the same technological developments, and will beat any other power source to a much greater extent than it does in real life. The only real drawback is that to be very economical the airplanes need to be very large, as in millions of tons in mass. They would need to be seaplanes, unless there is a massive runway buildout in this world that dwarfs anything in real life, which seems unlikely. Airplanes will exist in this world as a premium service providing rapid travel to the wealthy (the advantage over airships in travel time is very large), so it’s possible that relatively small but also very expensive nuclear-powered planes may be the first to appear in such a world.
We see that a world without fossil fuels would industrialize quite differently from our world, perhaps at a slower rate and with a lower standard of living, but making up for lost time later with the dawn of cheap electricity generation, and most of all once nuclear power becomes available. Biofuels play a large role at first but will be supplanted by synthetic fuels and in some cases nuclear reactors. Cars proliferate much like real life, but trains retain a larger role in long distance journeys. Trains will be especially viable against aircraft for overland journeys, providing unmatched speed at a given price point. Over oceans, zeppelins will dominate, with heavier-than-air craft finding a niche for time-sensitive wealthy travelers.
The largest changes in daily life are likely to be ships, including ocean liners and cruise ships as well as cargo ships, remaining sail-powered into recent times (and even today), air travel mostly being by airship, and long-distance overland travel being by train instead of by air. Economic development and thus population patterns will be substantially different, being centered on river dam, geothermal, and marine power sites rather than coal, oil, and gas fields.
Solar panels and wind turbines haven’t been mentioned in this post, because they require quite modern materials to be efficient enough to compete with the other energy sources mentioned in this post, materials which won’t be available at the technology levels we have been exploring. Solar energy, in particular, may have uses for solar thermal heating systems and in passive solar building design in such a world, to a much greater extent than in real life, even if photovoltaics won’t be viable until much later. By the same token, this post also hasn’t covered modern or near-future technologies like algae-based biofuels and ocean thermal energy conversion, to name but two.
This sort of world provides an intriguing setting for science fiction, alternate history, or other speculative fiction stories, because it enables you to root a story in an industrial-revolution-era or modern era level of technology while still keeping much of the technology quite different from real life. Such a planet would be the most different from real life technological development during the age of oil, our own era, compared to any other technological level we know of, making the modern age the most alien and fruitful one to explore for such a civilization, a characteristic we only seldomly see in worldbuilding projects. As such, seeing a setting like this used by skilled writers and artists would certainly be very interesting.