A Master’s Thesis by Steven Woods

This article is a summary of the Steven Woods’ Master’s Thesis: “Sail Freight Revival: Methods of calculating fleet, cargo, and labor needs for supplying cities by sail.” Master’s Thesis. Prescott College, 2021. The full thesis can be read Here.

Solar Electric USCG Inspected passenger vessel Solaris

Steven Woods earned his master’s degree in Resilient and Sustainable Communities at Prescott College in 2021, with an undergraduate degree in History from LeMoyne College. He has worked in museums for over 20 years and is making a career transition to the sustainability field after 6 years in the US Airforce. He is presently the Solaris Coordinator at the Hudson River Maritime Museum.

Ssil Freight Schooner Apollonia

Sail Freight is an ancient, proven, and fuel-independent means of transportation for both cargo and people. At scale, it could easily provide a means of provisioning cities across the world with food and other essential goods, while avoiding the use of strategic materials such as lithium, cobalt, biofuels, solar panels, electricity, and copper which are needed for the land-based energy transition. The challenge of moving to a sustainable transportation system is of critical importance, and the need to maintain a sufficient transportation capacity for food is literally a matter of life and death.

Sail Freight Vessel Tres Hombres

Sail Freight has gained popularity and visibility as a means of near zero carbon transport, and justifiably so. As complex Sail Freight networks have existed for at least 4,000 years in the Mediterranean, and possibly as long as 40,000 years in the South Pacific, the art of sailing is not new, and does not require complex or energy intensive technologies. Once a sail freight vessel is launched, the carbon emissions from the vessel are nearly zero, and service lives can cover several decades. As 90% of the world’s commerce moves by sea, and modern container ships normally burn over 100 tons of heavy fuel oil per day on their voyages, sail freight seems a good means of cleaning up global commerce.

Until recently, it seems no one has examined the scale at which sail freight must be adopted to fulfill these hopes and aspirations, nor has anyone looked at the auxiliary challenges of adopting sail freight, such as the capacity available to train windjammer sailors, build ships, and so on. Other challenges arise simultaneously to fleet capacity: Food systems and diets must change, warehouses be revived and staffed, superfluous shipping avoided, and foodsheds altered, while regulations change and physical infrastructure needs to be modified. Without a systems view of the whole readoption of sailing freight; any discussion thereof is unlikely to grasp the magnitude of the task at hand.

Black Seal unloading in Brooklyn

The first step in such a process is establishing a level of supply needed in a given city, which in our case with be the New York Metro Area. To survive, the city must have 2.5 kilograms of food per person daily. With a population of some 20,000,000 people, the New York Metro Area needs 50,000 metric tons of food per day, at a minimum, to prevent starvation. This gives us our daily requirement but does not give the full picture. A representative model of the NYMA Foodshed must be established, and the travel times from the food’s origin to destination must be calculated, alongside time for loading and unloading, as well as time for the ship to return to the origin for its next cargo.

The table below gives one such model for the New York Metro Area, at two levels of supply, using relatively small vessels, and illustrates the challenge before us quite well.

As can be seen, even at the lowest possible level of supply, it would require nearly 10,000 ships and 65,000 sailors to supply New York with food, and this without allowing time for crew rest, delays, or ship maintenance. At our current pace of launching Sail Freight Vessels, it would take near 44,500 years to build such a fleet. If we put all the shipyards in the US to work on the problem, however, it could be accomplished in as little as 13 years. While this feat would only be a start, as other cities will need their own fleets, these figures show the scale of the problem we are confronted with, and that it can in fact be solved quickly and effectively.

Of course, ships without trained crews are useless. The time to train windjammer sailors must also be considered. With an average program able to train around 650 sailors in a given year, the number of training program years needed to train the NYMA fleet’s crew requirement would be some 100 years, though with 8 such programs running concurrently this could also be accomplished in less than 15 years. The chart below shows the relationship between training program years and shipyard years and demonstrates that training a sufficient number of sailors will likely take longer than the construction of a sufficient number of vessels for the mission at hand.

sail training vessel

These figures all rely on a “Survey Average Vessel” of 111.25 tons capacity, and 6.5 crew members on average. These would be relatively small vessels, and larger vessels will need fewer of both ships and crew to give the same Fleet Tonnage. It is likely in the beginning of sail freight’s revival that small vessels will be involved, both reclaimed and newly built, which will have larger crew requirements and lower tonnages than the model here portrays. It is worth taking a comprehensive look at the current sail training resources in the US and subsidizing the training of windjammer sailors and captains as soon as practicable.

In the case of Sail Freight, fuel or energy efficiency is not applicable in the same way as with conventional transportation. The appropriate metric of efficiency is “Tons Per Sailor” as the major cost is labor. The higher the tons per sailor, the lower the cost of moving cargo becomes, and the large the vessel, the greater the tons per sailor. Further, this metric is effected by rig, as seen below.

Sloops and Scchooners fore and aft rigs

Through the intelligent choice of rig for specific applications, crew requirements can be brought down somewhat as larger vessels proliferate. Fore-and-Aft rigged vessels such as sloops, schooners, and brigantines generally have a smaller crew and are well suited to the coastal trading which will likely constitute much of a sail freight food movement system. Barks, Ships, and very large schooners will also likely see use on longer routes with far more cargo, but moderately sized crews.

Other challenges are present for reviving sail freight. Without substantial changes bringing the external costs of road and fossil fueled transport into the economic equations through weight-distance, tire, fuel, and carbon taxes, sail freight will remain economically uncompetitive excepting on very long routes with high-value cargos. As the price of fossil fueled transport rises, this competitiveness will even out, and short sea shipping under sail will most likely gain traction in the economic mix.

truck pollution

There are significant benefits to moving to sail freight for climate policy which makes the case for its adoption despite these challenges. It has been calculated that at a minimum, more than 220,000 tons of CO2e could be eliminated from US transportation emissions through supplying the NYMA with food via Sail Freight. This model assumes that all food is brought via 10,000 TEU container ships, which can move some 380 ton-miles on a liter of diesel fuel. Trucking, by comparison, nets only 1.58, while trains can get up to about 118-ton miles per liter of diesel fuel. If the latter number was calculated for trucking emissions instead of conventional maritime transport, it would be some 21 billion liters of diesel fuel and 63,560,087,101 Tons of CO2e avoided annually.  This amounts to some 362,000 barrels of oil per day.

pollution from ships

Alongside these benefits, shifting cargo to waterways will reduce congestion, wear, and tear on highway and rail systems, thus likely increasing the overall fuel efficiency of these same systems. Biofuels made from food wastes will be freed for use in supplying cities without nearby port facilities and demands on the grid for electrical power to fuel electric trucks will be lessened. In addition, the number of electric trucks to be built will also decline, making electrification faster and simpler in the long run.

Vermont Sail Freight Ceres

There are other advantages to Sail Freight which are less obvious than the environmental benefits and the challenge of training crews and building ships. For example, small vessels can be built inexpensively and with little needed in the way of facilities. Small ships can be built in the tradition of the Farmer’s Ships of the Aland Islands, which was effectively a combination of bot community supported agriculture and community supported shipping. Ceres of the Vermont Sail Freight Project is an example of just such a vessel, which made several successful voyages from Lake Champlain to New York City for the mere cost of some $20,000. With more advanced designs becoming available, planned for mass production and low cost in the style of the liberty ships of World War Two, these higher-capital ships will be in financial reach of cooperatives all around the four coastlines of the US and abroad.

Schooner Apollonia

This more democratic ownership model for transport, independent of fossil fuels, removes major costs for farmers in rural areas, especially as the cost of fuel and trucking rises. This can have the effect of lowering or stabilizing food prices for citizens while keeping more money moving to farmers and sailors. This is of mutual benefit to both city and countryside, clearly, but also reduces the power of banks and major corporations in both the transportation and food systems.

NYC Foodshed

Despite these benefits, there are many social and cultural adaptations which must be made to adapt to a Sail Freight future. The idea of constantly having fresh produce, in the off-season from 3,000 and more miles away will have to be abandoned. Diets must become more regionalized and localized, and the use of preserved foods instead of fresh in agricultural off seasons will become the rule. With innovative growing techniques, green houses, and other adaptations, there are likely to be small supplies of fresh foods in off seasons, but New York is unlikely to have shiploads of citrus arrive in good condition from Tampa after over a week in transit. Citrus juices, jams, preserves, and other shelf-stable confections will have to take the place of these foods where possible, and processing happen near the point of origin.

Next-day delivery will be impossible, and Just-In-Time delivery systems will be a thing of the past, replaced by acres of warehousing. wastes reduced, and material goods designed for repair instead of disposal. Superfluous Single-Use items such as coffee cups, plates, flatware, and bags should be banned on both environmental and logistical grounds. If every member of the NYMA used a single disposable coffee cup weighing 18 grams per day, the mass of cargo would amount to over 360 tons daily, or 131,400 tons of cargo in the year. If manufactured in Shanghai, 368 Survey Average Ships would need to be in constant motion between the two ports to maintain this entirely unnecessary practice.

Sail Freight Vessel Tres Hombres
Neoline Sail Freight

The future of Sail Freight is promising. Through the combination of modern knowledge and technology with proven older forms, a sustainable way of keeping cities alive can be created. While the challenge of building a Sail Freight future is certainly not easy, it can be done if we put our money, our time, and our backs to the task at hand. So doing could significantly alter the course of climate adaptations and climate change mitigation, provide hundreds of thousands of jobs, and democratize the economy in many beneficial ways. Given the gravity of our situation and the benefits to be gained, the case for Sail Freight should be clear to all.

Join the Conversation

1 Comment

  1. Nice summary Steven and glad to see you run some numbers from 60,000 feet. Up to now, humanity has tended to skew to a one size fits all approach. All oil, all coal, all wind. We have now moved into the hybrid era, where I suspect that the real solutions will take advantage of a combination of power suppliers for each specific application. All of that will be driven by complex economics. Maritime economic analysis has always been complex, but now it will actually become an order of magnitude more complex since when we design a ship for a job we do not just get involved in choosing the ship size and type, but now also need to choose a blend of powering options. I suspect just sail will become a rare sole solution, but sail will play a large role as part of a hybrid propulsion system on many marine transportation systems.

Leave a comment

Your email address will not be published. Required fields are marked *