If fuel consumption during shipment is a function of mass, then calorie for calorie, Soylent 2.0 consumes 4.375 times more fuel to ship than Soylent 1.5. [0] So, let’s consider a hypothetical Soylent drinker who lives 1,000 miles from the closest distribution center. How much more fuel would he or she consume by drinking Soylent 2.0 instead of 1.5?

Soylent ships via priority mail, which travels long-distance by air in the United States. Let’s assume that air freight consumes approximately 9,600 BTU per ton-mile [1], and a gallon of jet fuel (kerosene) contains 128,100 BTU [2]. In this case, Soylent 1.5 consumes 0.30 gallons of jet fuel per shipment, or 0.042 gallons per 2,000 calories [3]. Soylent 2.0 consumes 0.45 gallons of jet fuel per shipment, or 0.188 gallons per 2,000 calories.

So, for every 2,000 calories of nutrition provided by Soylent 2.0, we are also ‘drinking’ 24 fluid ounces of jet fuel to deliver it, compared to only 5.4 ounces for Soylent 1.5!

If our hypothetical Soylent drinker consumes 2,000 calories per day for a year, he or she also consumes 68 gallons of jet fuel for Soylent 2.0, vs. just 15 gallons for Soylent 1.5. This is equivalent to releasing 1436 pounds of CO2 [4] vs. 317 pounds: our soylenteer’s choice to drink Soylent 2.0 would release 1,119 more pounds of carbon dioxide per year than drinking Soylent 1.5.

I don’t understand why Rosa Labs is shipping mostly water on planes, especially given Rob Rhinehart’s focus on efficiency [5] [6]. Soylent 1.5 is calorie-dense nutrition optimized for storage and long-distance transportation. Literally everyone who can afford to drink Soylent also has access to water locally. Is the small convenience of not having to mix Soylent in a pitcher worth the significant environmental cost?

[0] (Box of Soylent 1.5 powder: 8 pounds, 14,000 calories, 1750 calories per pound. Box of Soylent 2.0 liquid: 12 pounds, 4800 calories, 400 calories per pound.)

[1] https://en.wikipedia.org/wiki/Energy_efficiency_in_transportation#US_Freight_transportation

[2] https://en.wikipedia.org/wiki/Gasoline_gallon_equivalent#Gasoline_gallon_equivalent_tables

[3] These calculations disregard the first-mile pickup and last-mile delivery via truck, which are likely to be a small fraction of the fuel consumed by air freight.

[4] https://www.eia.gov/environment/emissions/co2_vol_mass.cfm