Solar Shipping
Contents
Cargo Container Ships
On a solar ship - how many solar panels of 20% efficiency can fit on it- using the surface area of the largest container ship [1]. A container ship of 500 TEU [2] capacity costs $10M, and a used one goes for $4M. [3]. Largest container ship is 400x60 meters, or 24,000 square meters. [4]
Small container ships weigh 50k tons. Large ones weigh 200k tons. [5]
Each square meter produces .2kW at best. That makes it 4800kW.
$400/kw. $2M for the panels.
Cargo ship uses 16 tons of fuel per hour. Fuel cost is $300/ton. $38M/year in fuel.
About 8000 hours per year. 16x300x8000=$38M. It is about $100M for a 12k TEU container ship [6]. This means solar payback time is under 1 month. PV costs less than the engine itself. 1 container ship creates as much pollution as 50M cars.
A large container ship uses 80MW of power. [7]. This makes the surface area of a solar ship 1/17 the power. Cost of engine? Hard to tell. If 2300 tons, then $5M if cost of engine is a dollar per pound. It's likely much more than that. A 2MW diesel locomotive is up to $2M for comparison. So the cost of replacing with PV is equivalent, probably much cheaper if we discount the electric motor cost on the cargo ship. However, electric motors are highly modular, so probably not a bad deal to go with electric for lifetime and simplicity.
Diesel locomitives are 2.2MW [8].
With telescoping panels, solar come to 1/6 the power of a diesel drive train. This may be a case for solar trailers, which just carry extensible solar panels behind the ship. Anyway, the effort to save burning 16 tons of fuel per hour are worth investigating.
Night time power - could be addressed via solar hydrogen production, but that is questionable.
First Order Calculation Summary
- If we use the area of an existing large container ship, we can harvest 1/17 the power required
- With telescoping panels, we can triple this and thus we can harvest 1/6 the power required.
- If we use a solar trailer - a convoy that just houses more solar panels, we can gain another factor of 3. Then we have half the power of an industry standard container ship.
- This still gets us to 1/8 the industry standard requirement, due to 4x the time being night time.
- Putting on a 16MW wind turbine on the ship can be one addition to the power base, and using a solar trailer with another 16 MW wind turbine would produce 32 MW, for a total of 72 MW during the day, and 32MW during the night. This would give about half the travel time for any voyage compared to an oil fueled cargo ship.
Next question - fuel savings is $19M/year. Profit margin of shipping is 10%. There are about 5500 container ships [9]. Net of shipping companies was about $220B [10], or $40M per ship. Just the fuel savings are about half the net revenue. Actual revenue from solar shipping would be $20M per ship (half the rate of oil fueled ship) with $19M per ship saved in fuel, thus getting the net revenue for solar shipping equivalent to the net revenue of standard shipping from first order calculations.
Conclusions
While the solar large-scale vessel can match industry standards to within 1/3 of the speed by using a single power trailer - at significantly lower cost - A small cargo ship can be solar and match industry standards of speed and cost by employing a power trailer. Without using a power trailer, a smaller solar cargo ship can meet industry standards of performance - at much lower cost and environmental footprint.
Specifically - analize a 100 TEU ship operating within the Economy of Affection, which costs 10x less to build, and has an environmental footprint (energy use) at least 100x lower than conventional diesel oil options.
