The world population clock now reads 7,725,982,777. With population growth, it is predicted to reach about 10 billion in the year 2055. That’s 36 years from now. But there’s a big problem.
Where is the food going to come from to feed all of these people? It takes fertile land to grow food and that now requires fertilizer and that requires energy to manufacture. It requires water to grow crops and that too is becoming a problem and it will require energy to pump water to higher ground. Food will need transportation to where it is eaten and that requires energy. And, in addition to food, which is essential, people need housing, heating, and cooling, and transportation to work and play. These things need energy, too.
Where does energy come from? Most of the energy for these things currently comes from fossil fuels like coal, oil, and gas. But these are one-time use sources of energy, and so people who are presently children by the time they are middle-aged adults will need large supplies of energy coming from some source other than fossil fuels.
The energy source of the future will involve various ways of extracting energy from the sun. Water evaporated from the oceans by the sun, falling onto the land, forming rivers, and the energy of their falling from behind dams through electric turbines and being converted into electricity has been half exploited already. There will be more, but not a much higher percentage of increase from that source.
Wind power, derived ultimately from the sun, and collected with wind turbines will continue to provide more power, but there is a need to convert that electric power into food.
There are solar panels which convert solar light directly into electricity and that is almost economically equal in efficiency to power created by wind. Both of them are feasible and workable, and now being done. But the amount now available falls far short of what is and will be needed to feed the people of the world.
In each of these cases creating energy from sources other than fossil fuels requires electricity. Getting that electricity through the various processes needed to get food to us is doable, but it isn’t easy There is need for the electrical energy in the fields where the food is being grown. Current farming requires many forms of powered machinery, such as plowing the fields, planting the seeds, controlling the watering, harvesting the crops, getting those crops from where they are grown to us. Today that energy is oil and gas, but as those supplies run out over the life expectancy of people living today, they will need to be replaced with something else, and that is probably going to be electric power. It can be done, but it will cost more time, effort, and money to get it done.
It seems impossible today, but as electrically powered farm equipment comes into use the likely ways of providing it in the fields will be overhead wires like those that used to power streetcars and lithium battery-powered farm equipment. Or, sorry folks, human labor. Of course, after a while, much of the work will be done by robotic machinery.
According to a Stanford University study, it would need an equivalent of “about 3.4 billion Nissan Leafs. This would use 32% of the identified resources (all known lithium in the world) or 82% of the reserves (all lithium that is currently economic to produce).” That is a rough estimate of the energy needed to operate the farm machinery to feed the people of the world.
After the major wars are finished trying to sort these things out, the population will likely drop back to 1 AD levels as farming by human physical effort returns. The technology for making an electrically powered farm society will be known. That will take a while to get up and running effectively, and the world population can then expand to that new carrying capacity of the new food supply.
An electric-powered food creation society will be a more stable one than our one-time-use fossil fuel-based one, which will soon end.