Try out your 30-day free trial and free audiobook with Audible by clicking here: http://www.audible.com/reallifelore This video is a sequel to one of my previous videos. I try my best to explore what a building that could "comfortably" house the entire human race would look like within this. I didn't have enough time to cover some of the math in the video because I was worried it would get too boring, so for anybody who's interested I've written it all out below... 80% of the US freshwater source is currently consumed by agriculture. Aeroponics reduces the amount of water needed by 98%, and eliminates the need to use chemical fertilizers and pesticides. It seems that the most efficient crops that can be produced are sweet potatoes and regular potatoes. Sweet potatoes grow about 13.5 tons per hectare, or 1,350 tons per square kilometer. This can be translated to 54,000 calories per hectare per day which is equal to 5.4 million calories per day per square kilometer. If everybody is given a diet of 1,500 calories per day, then 1 square kilometer of sweet potatoes is enough to feed 3,600 people per day. Sweet potatoes are generally between 12 and 15 inches in height, so giving them a little more space of about 1 meter and stacking 1,000 layers on top of eachother and we could fit 1,000 square kilometers into 1 cubic kilometer. Using hydorponics, (a method of growing plants without using soil, but instead using nutrient rich water solution, where the plant roots are directly exposed to the solution) and we can increase our raw yields by around 280%. Thus, we could then expect to feed up to 10,080 people per day per square kilometer, but then we could further increase the efficiency with aeroponics (another method of growing plants in which nutrient rich water is vaporized and sprayed directly onto the roots of crops.) Using this method we could further increase efficiency by between 50% to 270% over traditional hydorponic methods. If the far side of this could be realized, we could potentially be feeding 27,216 people per square kilometer per day of space. Now, extended to the cubic kilometer that means that we could actually be feeding 27,216,000 people per day per cubic kilometer building full of sweet potatoes, since we would multiply 27,216 by 1,000 since there would be 1,000 layers. Therefore if we build 275 of these cubic buildings to feed the entire human race a diet of sweet potatoes, or have a farmland about the size of Ecuador for the same purpose, we could in theory feed the entire species. 33.8% of Brazil’s land is considered arable and suitable for farming, which would translate to 2,878,329 square kilometers of potential farming space, more than enough to feed us all several times over “in theory.” Obviously a diet of only sweet potatoes is not entirely healthy, but in an emergency situation or hypothetical situation like this it appears to be the most efficient food for us to consume. If I’m wrong about any of this please feel free to correct to me or leave your own ideas :) Sources: http://www.fao.org/docrep/t0207e/T0207E04.htm http://www.businessinsider.com/10-crops-that-feed-the-world-2011-9?op=1/#cassava-6 https://en.wikipedia.org/wiki/Aeroponics http://data.worldbank.org/indicator/AG.LND.AGRI.ZS http://www.sciencedirect.com/science/article/pii/S0304423807003846 https://www.researchgate.net/publication/234520423_Comparison_of_vegetative_growth_and_minituber_yield_in_three_potato_variety_in_aeroponics_and_classic_hydroponics_with_three_different_nutrient_solutions http://www.un.org/esa/population/pubsarchive/chart/14.pdf http://www.businessinsider.com/nasa-data-shows-the-world-is-running-out-of-water-2015-6 https://www1.nyc.gov/site/planning/zoning/districts-tools.page http://www.techtimes.com/articles/92543/20151008/ever-wondered-how-many-solar-panels-are-needed-to-power-up-the-world-heres-the-answer.htm https://en.wikipedia.org/wiki/List_of_countries_by_electricity_consumption https://en.wikipedia.org/wiki/Itaipu_Dam https://en.wikipedia.org/wiki/Water_resources_management_in_Brazil http://www.slate.com/articles/technology/future_tense/2012/06/food_security_what_crops_will_feed_the_world_if_we_run_out_of_farmland_.html Music is by Brandon Maahs, check out his website for more great stuff! www.brandonmaahs.com Image Credits: http://stefan-morrell.cgsociety.org/ Please Subscribe: http://bit.ly/2dB7VTO Follow us on Facebook: https://www.facebook.com/RealLifeLore/ Follow us on Twitter: https://twitter.com/RealLifeLore1 Patreon: https://www.patreon.com/RealLifeLore French Subtitles Written by: Emel Önal Subreddit moderated by: Oliver Bourdouxhe Special Thanks to Patrons: Joshua Tavares, Wesley Jackson and Matthew Mikulka Videos explaining things. Mostly over topics like history, geography, economics and science. Business Email: thereallifelore@gmail.com