Its all about the power source, if you can get green electricity then the figures change.
Then Methonal is not green
DNV has developed a tool for shipping to sort through the various types of alternative fuels, their pros and cons:
https://www.dnv.com/services/alternative-fuels-insight-128171
It is not only shipping that is looking for new fuel sources:
Green methanol can even be made from captured CO2.
Scholarly explanation:
https://www.sciencedirect.com/science/article/abs/pii/S221334371830736X
I never understood the exhaust scrubber requirement. The clouds and the rain do the same thing in the middle of the ocean. Why waste the money?
Not all ships equipped with scrubbers are open loop.
Korean shipyards are seeing opportunities from the switch to green fuels in the future:
They are not alone, but there are still some laggards that sees only problems with every new development.
Not all, but nearly all…correct?
You are probably correct though I can only speak of the ones I am familiar. The Matson (ex-Horizon) D7’s running to Alaska I believe are closed loop as are the Interlake ship running the Great lakes. In 2020 the number of ships with closed loop amounted to 65 out of 3756 equipped with scrubbers. So obviously not many.
How cost effective are those closed loop systems? I wonder if it’s better just to buy the more costly LSHFO.
Are they using a limestone slurry mixture? Or dry scrubber?
When wet scrubbers first appeared on land in coal power plants, they all were “closed loop” (and still are) with plenty of extra buildings full of water treatment and material handling equipment. It’s kind of hard to cram this equipment on a ship. More importantly, is the ship going bring aboard another person to operate and maintain the complex system?
I’m curious about the hybrid EGCS units. In theory, it’s the best of both worlds but theory vs in practice are often far apart.
Scrubbers are a temporary solution only. They help to remove SOx (and Particle Pollution) to meet present IMO regulation for open waters and ECA zones:
Here is a presentation of Marine scrubbers for those who wants to study this in more detail:
To meet future requirements for “Zero Carbon Emission” while still burning HFO, MDO or LNG will require a lot more complex “Carbon Capture and Storage” system:
Or change to a carbon free fuel, or alternative forms of propulsion yet to be developed.
Yes, but not in a volume that would be sufficent. Using natural gas is currently the most economical method.
This is about the future, not the present. IMO target is to reach Carbon Neutrality by 2050.
LNG is the primary choice of the present, but it is a a highly CO2 and Methane polluting fuel.
It will have to be phased out by 2050 (or replaced with Liquified Biogas)
As the price for LNG is now high some dual fuel ships change back to HLSFO for the time being.
In Norway two LNG powered RoPax ferries will be converted to dual fuel:
Smaller LNG powered ferries are being converted to either hybride or fully electric propulsion,.
ALL newbuilt RoPax shuttle ferries in Norway are full Electric, of Hydrogen powered.
PS> Electric power and hydrogen are made using renewable sources, mainly hydro but wind, wave and tidal power are being tested.
Solar power are mainly used in private houses and cabins in the mountains etc.
Since sunshine comes in lumps in Norway, it is not very useful as large scale “solar farm”.
Insights from the shipbroker show that 61% of tonnage ordered last year (35% by number) was alternatively fuelled. LNG still leads, but is NOT a viable fuel for the future.
Could Ammonia be the winner?:
A new contender for the throne?:
Timely question:
Maybe this is the answer??:
While we wait for the ultimate fuel of the future there are ways to reduce fuel consumption on existing ships burning fossile fuels:
https://vesselperformance.info/2023/02/17/yara-marine-secures-vessel-contract-for-fuelopt/
Good for the environment and good for the bottom line.
PS> Systems like that has existed since the 1980s on OSVs in Norway.
Surely that was manually controlled?
PC’s control in the 80’s?
Hunterstad had lots of their systems on yachts, they just added an EGT gauge to know you weren’t overloading.
Seems to have faded away now but any diesel on a displacement hull will benefit.
It was NOT manually controlled in the sense that somebody adjusted engine RPMs or pitch.
IIRC it was called an “Econometer”, the desired speed was dialed in and the RPM/Pitch was adjusted to the most economical settings, depending on changing conditions.
In 1989 I inspected the AHTS Far Scout, built at Ulstein in 1987, UT 712 design She was part of the fleet of 18 tugs used for towout and positioning of the Ekofisk Barrier:
The young Mate showed me around on the bridge with all the fancy gadgets that was available at the time, incl. Econometer, portable Joystick etc.
When I sat down with the old Captain I asked; “do you use all those gadgets?”
“Yes, but when things gets difficult I get back on manual control”