The green credentials of LNG are well known. In the gas-for-transport market, a classic example of its use is to power sea and ocean going vessels. Modern specialist LNG-carrying vessels have reliquefaction capability that captures “boil off” to use as fuel for propulsion. Alternatively, other vessels use LNG as a straight substitute for marine fuel oil.
If we take the example of the aptly named passenger ferry “GREENFERRY” that operates between Brunsbüttel and Cuxhaven, the use of LNG over a period of six months (March 2021 – August 2021) has meant that the combustion of 2,000 tons of diesel was avoided. That entailed the release of 90% less nitrogen oxide and 20% less carbon dioxide into the atmosphere.
However, Synthetic Natural Gas, or “SNG” is, arguably, even greener. Without getting too scientific, SNG describes a variety of natural gas alternatives that are as close as possible in composition and properties to natural gas. Gasification is a non-combustion heating process that turns solid carbon fuels into hydrogen, carbon dioxide and carbon monoxide.
If the base material is plant matter, compost or other waste matter, the gasification process is either thermochemical or biochemical and the product is called bio-SNG.
Alternatively, if the hydrogen is created by electrolysis (usually using surplus renewable energy), this process is often referred to as “power-to-gas” and the product: “syngas”. The following methanation process, a chemical reaction aided by a high temperature catalyzer, turns the carbon dioxide and carbon monoxide into methane, which is the main component of natural gas.
Replacing heavy fuel oil with syngas from power-to-gas reactors that also capture carbon could potentially cut 100% of emissions all along the value chain.
On 29 September, “ElbBLUE“ became the world’s first ship to use SNG after stemming 20 tons in the Elbehafen in Brunsbüttel, made possible by LIQUIND (logistics), MAN Energy Solutions (energy technology), Elbdeich (the shipowner); and Unifeeder (the charterer).
SNG is hotly tipped by many as a “future fuel”. Watch this space.
Container ship “Elbblue” receives world’s first synthetic natural gas bunker delivery