Questions about LNG

Sir,

Some questions regarding Liquefied Natural Gas (Delayed Glen Sannox ferry may have two year wait for LNG fuel - Banner May 13).

For information LNG is natural gas converted to liquid at a temperature of –162°C which reduces its volume by a factor of 600, making it easier to transport.

Firstly, what is the real green footprint, cradle to grave, given the gas is extracted, liquefied, shipped 8,000 miles from Qatar to Kent and then 460 miles by road to Ardrossan, all the while at –162°C? Did anyone do the sums to check the environmental benefits outweigh the environmental costs?

I’m not an engineer, but I’ve been advised the ship’s engines run on diesel all of the time. Once under steady cruising conditions, 90 per cent of the diesel can be replaced by gas which produces 30 per cent less carbon dioxide than diesel. I understand the system is designed for LNG tankers on ocean voyages, not the 55-minute Ardrossan to Arran service, where the LNG can only be used at best midstream. So how many minutes of environmental gain (at 30 per cent of diesel equivalent) are we getting against the environmental costs?

What impact has the dual fuel design had on the cost and complexity of the build, and the (ahem) timescales?

Who insisted on dual fuel and why? Did anyone consider battery powered ferries, like those being deployed in Norway?

Given the LNG combustion risks, how far are the proposed LNG storage bunkers from the new Ardrossan ferry terminal? What is a safe distance?

To summarise, as we jokingly used to say in my industry: who sold you that then?

Yours,

Douglas Templeton,

Whiting Bay.