LNG & Marine Shipping #clearfacts #LNG #marinesafety

#clearfacts#LNG#marinesafety

Worldwide, the demand for natural gas is increasing. As a result, a number of liquefied natural gas (LNG) export terminals are proposed or in progress in Canada. Both the amount of LNG transported by ship and the number of ships fuelled by LNG are expected to increase in Canadian waters.

Although the transport and use of LNG by ship are not without risks, measures taken to reduce those risks have resulted in the safe transport of LNG by ship for the past sixty years.

This site’s purpose is to share objective information about the use of LNG as a cargo and fuel source for the marine shipping industry – including the benefits and risks of LNG use and carriage, and what’s being done to reduce those risks – and to encourage informed conversations about these issues.

This site was created by Clear Seas Centre for Responsible Marine Shipping, an independent research centre that supports safe and sustainable marine shipping in Canada.

About Natural Gas

Natural gas is a naturally occurring flammable hydrocarbon used extensively as a fuel.

Once extracted from the ground, natural gas is processed to remove components such as:

Hydrogen Sulphide
Nitrogen
Carbon Dioxide
Water
Butane
Ethane
Propane
Learn more about natural gas exploration and production in Canada

Refined natural gas, which is mainly methane, is transported by pipeline to population centres for industrial, commercial and residential use, primarily:

Electricity
Transportation
Cooling
Heating

For transport by ship, natural gas must first be cooled to a liquid to significantly reduce its volume. Known as LNG, it requires 600 times less space while kept at -160°C and near atmospheric pressure for efficient transport over long distances.

Natural Gas Emissions

Natural gas emits significantly fewer air pollutants than most other fuels and is non-corrosive and non-toxic.

Natural gas is viewed by many as an abundant, cost-effective and cleaner fuel and is expected to overtake coal and become the second leading source of energy worldwide – behind oil – by 2040.

Common Pollutants: SOx, NOx and Particulate Matter

Compared to conventional fuels such as coal, heavy fuel oil, diesel and gasoline, the combustion of natural gas produces 85-90% less sulphur oxides (SOx) and particulate matter and 35-85% less nitrogen oxides (NOx), depending on engine type. With increasingly strict air pollution regulations in effect in many areas around the world, replacing other fuels with LNG will improve air quality and reduce harm to human health and the environment.

Greenhouse Gas Emissions

Estimates of the potential reduction in climate change effects by adopting natural gas as a fuel vary widely. Determining the overall impact on climate change requires consideration of the various greenhouse gases released throughout the supply chain, from natural gas's extraction from the ground to its combustion in an engine.

When burned, natural gas produces an average of 15% to 29% less carbon dioxide than conventional fuels. The actual value is dependent on the source of the gas and the conventional fuel being compared. For example, natural gas produces approximately half as much carbon dioxide as coal does during combustion.

These apparent benefits of natural gas combustion are reduced by the impacts of:

Lifecycle emissions

Different methods to extract, process and transport natural gas produce different amounts of carbon dioxide.

Methane slip

Releasing natural gas (methane) inadvertently into the atmosphere through leaks during handling or transport or due to incomplete combustion has up to 25 times the climate warming effect of carbon dioxide.

For instance, the lifecycle greenhouse gas emissions of LNG are estimated to be 6% to 10% less than emissions from heavy fuel oil, which is currently the most commonly used shipping fuel. Some studies report even less or no benefit, depending on the amount of methane slip that occurs. The range depends on efficiencies in production, transport and handling to reach the end user, and the types and efficiencies of ship engines used. By using efficient engines, careful LNG transfer procedures, and education and training, the amount of methane slip that occurs during ship refuelling and operating can be significantly reduced, increasing the benefit from using LNG as a marine fuel.

Fuel lifecycle climate warming impact

When comparing the CO2-equivalent emissions of different fuels per 1 tonne of cargo transported 1 km by ship, the total climate warming impact of LNG exceeds that of heavy fuel oil when the amount of methane slip from LNG use is greater than approximately 1% of the volume of LNG.

Methane slip as a percentage of fuel Lifecycle GHG emissions [g CO2-eq./ tonne km]
Marine Gas Oil (MGO)
Heavy Fuel Oil (HFO)
LNG from Qatar

Research is underway to reduce the climate change impacts of natural gas use by identifying ways to prevent methane slip and also integrating renewable gas sources such as biomass into the supply.

Natural Gas in Canada

Canada was the fourth largest producer of natural gas in the world with 5% of global production in 2017. Approximately half of Canadian natural gas is exported by pipeline within North America, for a net value of $6.7 billion in 2017.

In response to the increasing demand for natural gas around the world, a number of LNG export terminals have been proposed in Canada to move natural gas to overseas markets.

A total of 18 LNG export facilities have been proposed in Canada:

Stewart LNG Export Project
Stewart, BC
Kitsault Energy Project
Kitsault, BC
Orca LNG
Prince Rupert, BC
New Times Energy
Prince Rupert, BC
Watson Island
Prince Rupert, BC
Kitimat LNG
Kitimat, BC
LNG Canada
Kitimat, BC
Cedar LNG Project
Kitimat, BC
Discovery LNG
Campbell River, BC
Woodfibre LNG
Squamish, BC
Steelhead LNG/Kwispaa LNG
Sarita Bay, BC
WesPac LNG Marine Terminal/ Tilbury Pacific LNG Jetty
Delta, BC
Triton LNG
Location to be determined
British Columbia
Energie Saguenay
Saguenay, QC
Stolt LNGaz
Becancour, QC
Quebec
Goldboro LNG
Goldboro, NS
Bear Head LNG
Canso, NS
AC LNG Canada, Byers Cove
Guysborough, NS
Nova Scotia

Combined, these terminals have a total proposed export capacity of 87.5 million cubic metres per year of LNG. Transporting this volume of LNG to overseas markets would require LNG carriers to make approximately 330 trips per year.

Approximately 330 LNG Carrier Trips

Canada has two LNG facilities currently in operation:

Canaport LNG

Canaport LNG at the Port of Saint John, New Brunswick has been importing LNG from overseas, storing it, and returning it to natural gas to supply the North American pipeline grid since 2009.

Tilbury LNG

Tilbury LNG plant in Delta, British Columbia has been liquefying natural gas since 1971 for local use. A recent expansion and supply agreement has made Tilbury LNG the first facility regularly exporting LNG to China, using shipping containers to transport the LNG.

LNG as a Marine Cargo

The number of LNG carriers in operation is increasing with over 525 vessels worldwide in 2018. A single LNG carrier can transport enough energy to heat the homes of approximately half the population of Saint John, New Brunswick for a year.

LNG Carrier Saint John, New Brunswick

Transporting natural gas as a marine cargo requires a number of steps:

LNG Lifecycle

Gas Field
Pipeline
Liquefaction Facility
LNG Storage Tank
LNG Carrier
LNG Storage Tank
Regasification Facility
Pipeline
End User

Gas Field

Gas is extracted from the ground and processed to remove impurities and other gases

Pipeline

Gas is transported to population centres and export terminals

Liquefaction Facility

Gas is cooled to -160ºC to condense into 600 times less space

LNG Storage Tank

LNG is kept liquid in an insulated tank near atmospheric pressure until it can be loaded on a ship

LNG Carrier

LNG is kept liquid in insulated tanks near atmospheric pressure with no further cooling needed during transport

LNG Storage Tank

LNG is kept liquid in an insulated tank near atmospheric pressure until it is needed as a gas

Regasification Facility

LNG is converted back to gas using a heat exchanger, in a process called regasification

Pipeline

Gas is transported from import terminals to population centres

End User

Gas is used to cook food, heat and cool homes, generate electricity, and power vehicles

Back to lifecycle

LNG Carriers

In January 1959, the world's first LNG carrier – aptly named the Methane Pioneer – transported approximately 5,090 cubic metres of LNG from Lake Charles, Louisiana to the United Kingdom. Since then, LNG carriers have undergone a 50-fold increase in capacity – the largest LNG carrier today can transport 265,000 cubic metres of LNG.

Both rectangular and spherical tanks are commonly used in LNG carriers today:

LNG Carriers

LNG carriers are designed and constructed with many safety features including insulated tanks and double hull structures. In the past 60 years of LNG carriage, there have been some minor LNG spills during cargo loading and unloading operations, but no incidents resulting in a spill of LNG from a ship while in transit have been reported.

Other safety mechanisms to prevent LNG spills include:

  • Overfill protection for cargo tanks to automatically stop loading when a certain level is reached.
  • Overpressure protection valves on each tank to keep the tank at the ideal pressure throughout the voyage.
  • Extensive safety procedures and training for safe operations.

LNG Import and Export Terminals

LNG import and export terminals are located throughout the world, allowing ships to transport natural gas from regions where it is produced to regions where it is used.

As of 2018, there were 132 LNG import (regasification) terminals and 48 LNG export (liquefaction) terminals. More terminals are in the planning and construction stages.

  • Regasification (import) terminals
  • Liquefaction (export) terminals

Safe Transport of LNG by Ship

If spilled, LNG is unlikely to contaminate water or soil as it will not have time to sink or be absorbed before returning to a gas.

In its liquid form, natural gas is not flammable, but if spilled, LNG will create a vapour cloud as the liquid rapidly reverts to a gas and mixes with oxygen. The colourless, odourless vapours can accumulate near the spill or drift over land or water, and be ignited by heat, sparks, flames, static electricity or other sources of ignition, given the right vapour mix of oxygen and gas.

A spill from handling or transporting LNG could cause harm through:

  • Suffocation due to vapour clouds displacing oxygen.
  • Cryogenic (flash freezing) damage to people or infrastructure.
  • Ignition of vapour cloud causing burns to people or infrastructure.

LNG spills are unlikely due to the many safety mechanisms in place to prevent spills, including:

  • Protocols for safe operations - including training exercises, inspections, and certifications.
  • Emergency shut-down system to halt LNG transfer for any reason.
  • Emergency release couplings to protect against spills if the transfer mechanism detaches.
  • Mooring quick-release hooks with built-in fail-safe features.
  • Tethered tug assistance and local pilot(s) to bring LNG carriers into and away from the port.
  • Enforced safety zones surrounding the LNG carrier to exclude other vessels while near or at the terminal.
  • Travel restrictions when LNG carriers are near populated areas to transit during daylight hours and at a reduced speed.

These precautions, along with regulations and safe handling methods, have proved effective in preventing LNG spills in the past.

Security concerns after the 9/11 terrorist attacks prompted studies that modelled the worst-case LNG spill scenario as being the result of a deliberate action (such as a terrorist attack). In the model of a worst-case scenario with a significant breach of LNG tanks, a “pool fire” could develop as spilled LNG pools on the ocean surface, begins evaporating, and ignites. This outcome requires natural gas to mix with air in a concentration of 5% to 15% by volume as well as a source of ignition. Although unlikely to occur, this scenario presents a risk of damage to equipment within 0.5 km and second-degree burns to skin within 1.5 km. Depending on the proximity of the spill to land and the prevailing winds, a vapour fire could be pushed away from the spill and over land, potentially reaching up to 3 km.

The following additional safety precautions can be used to prevent deliberate attacks:

  • Crew security screenings.
  • Ship and terminal security systems.
  • Effective use of LNG carrier escort tugs and vessel exclusion zones near ports and terminals.
  • Focused surveillance and searches.
  • Emergency response coordination and communication with first responders and public safety officials.

The vigilant application of regulations and safety precautions have resulted in the safe transportation of LNG for 60 years, with no spills of cargo from an LNG carrier in transit.

Safety measures required at Canaport LNG at the Port of Saint John include:

  • a security screening of the vessel crew by Transport Canada.
  • tethered tug support.
  • a safety exclusion zone of 0.5 nautical miles (925 m) around the LNG carrier while underway.
  • no anchoring within 1.5 nautical miles (2.7 km) of the LNG carrier.
  • no overtaking of the LNG carrier while underway in the harbour.
  • a 0.3 nautical mile (620 m) radius from the centre of the terminal is off-limits to all marine traffic except tugs and service craft assisting the LNG carrier during LNG unloading operations.
Learn more about terminal safety precautions: LNG import terminal in Boston

Regulations for LNG Transport by Ship

The safe transport of LNG by ship is governed by regulations at the international, national, provincial and municipal levels. These regulations provide consistent standards for the safe handling, storage, carriage and use of LNG by ships.

Transport Canada is responsible for implementing and enforcing international regulations through the Marine Transportation Security Regulations and Transportation of Dangerous Goods Regulations. LNG carriers, like other foreign ships calling on Canadian ports, receive regular Port State Control inspections to ensure compliance with regulations.

An international safety management code became mandatory for all gas carriers on international voyages as of July 1998. This code protects against safety and pollution risks involved in ship operations. Additionally, under the International Ship and Port Facility Security Code, ports, LNG terminals and LNG carriers are required to have an approved security plan and designated security officers prior to operation.

LNG import and export facilities are classified as industrial sites in Canada and are subject to federal, provincial and municipal standards, codes and safety regulations. These regulations are regularly updated to ensure that the health, safety and security of the Canadian public and environment are protected. The Canadian Standards Association has a specific standard for LNG production, storage and handling to ensure the safe operation of LNG facilities in Canada.

Learn more about international LNG regulations

While the preventive measures to avert a spill are well developed, regulations for compensation for damage caused by an LNG spill are not fully established. For the purposes of liability and compensation, LNG is considered a Hazardous and Noxious Substance (HNS). The International Maritime Organization's 2010 HNS Protocolratified by Canada but not yet in force – is based on the successful model devised to address pollution damage from oil spills, known as the Polluter Pays model.

LNG as a Marine Fuel

Recent commitments by the International Maritime Organization to reduce the marine shipping industry’s sulphur oxide and nitrogen oxide emissions has intensified the search for cleaner fuels. LNG as a marine fuel is seen as a positive move for cleaner air.

In Canada, fuelling ships with LNG has increased rapidly in recent years, particularly among ferries and domestic cargo vessels, due to stricter regulations to prevent air pollution. New technologies to recover natural gas have created a gas surplus in North America. LNG’s lower emissions profile, increased availability, and competitive cost have made it an attractive option for ship operators in Canadian waters.

As of May 2018, the world fleet included approximately 120 vessels equipped to use LNG as a fuel, with another 132 vessels on order. Many new-built ships have dual-fuel engines to allow operators to use either LNG or oil, with LNG used as the main fuel and oil used as the ignition fuel, and some existing vessels have been outfitted for LNG fuel with new engines and larger storage tanks.

Learn more about the technical requirements to convert ships to use LNG

The Global Marine Fuel Market

Although the infrastructure required to support widespread use of LNG as a marine fuel is currently a limiting factor in adopting its use, ports that provide marine fuelling services around the world are in the process of developing or expanding capacity for LNG fuelling. The majority of such ports are expected to offer LNG as a marine fuel in the near future, with many LNG fuelling facilities in Europe and Asia already in operation.

Early adopters of LNG as a marine fuel include ferries and cruise ships, as these vessels operate near shore and often within Emission Control Areas where sulphur oxide emissions are limited to 0.1% of fuel burned. Lacking traditional fuelling infrastructure (such as barges and jetties) for LNG fuelling, many vessels receive LNG delivered by truck.

LNG’s share of the global marine fuel market is expected to grow substantially after 2020.

Initiatives Underway

Select initiatives underway to incorporate LNG into Canada’s marine shipping industry include:

BC Ferries

BC Ferries currently operates five LNG powered ferries providing significant savings in fuel costs and emissions. LNG is approximately half the cost of ultra-low sulphur marine diesel, and the annual emissions reductions for one ferry are estimated at 9,000 tonnes of CO2 equivalent or eliminating 1,900 passenger vehicles from the road.

Fortis BC

FortisBC provides LNG for the West Coast marine industry with truck-to-ship onboard LNG fuelling. LNG is trucked from the Tilbury LNG plant to BC freight and passenger ferries. FortisBC has been performing approximately a dozen onboard marine fuelling operations a week since December 2016.

Groupe Desgagnés

Groupe Desgagnés has added five dual-fuel product carriers to its fleet operating in the Great Lakes and St. Lawrence, Atlantic and Arctic waters. The ships can run on LNG, heavy fuel oil or marine diesel and are double hulled and built for safe navigation in Arctic waters.

Seaspan Ferries

With the support of the BC government and the Snuneymuxw First Nation, Seaspan Ferries commissioned two new dual-fuel vessels in April 2017 to bring its fleet to seven vessels. The new vessels can use either LNG or diesel fuel and have battery back-up power.

Transport Canada

Canada has been preparing for the use of LNG as a marine fuel for some time. Starting in 2013, Transport Canada commissioned reports to assess the LNG supply chain on Canada’s West Coast and also the Great Lakes and East Coast. In 2017, Transport Canada issued interim Requirements for Vessels Using Natural Gas as Fuel. New vessel construction and equipment regulations are expected to be released in the future. These requirements include guidelines for safe LNG fuelling operations.

About Clear Seas

Clear Seas Centre for Responsible Marine Shipping is an independent research centre that supports safe and sustainable marine shipping in Canada.

Clear Seas was established in 2014 after extensive discussions among government, industry, environmental organizations, indigenous peoples and coastal communities revealed a need for impartial information about the Canadian marine shipping industry.

Clear Seas received seed funding in 2015 through equal contributions from the Government of Canada (Transport Canada), the Government of Alberta (Alberta Energy) and the Canadian Association of Petroleum Producers. Our funders saw the need for an independent organization that would be a source of objective information on issues related to marine shipping in Canada.

As an independent research centre, Clear Seas operates at arm’s length from our funders. Our research agenda is defined internally in response to current issues, reviewed by our research advisory committee, and approved by our board of directors.

Our board of directors is composed of scientists, community leaders, engineers and industry executives with decades of experience investigating human, environmental and economic issues related to our oceans, coastlines and waterways.

Our reports and findings are available to the public at clearseas.org/en

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  4. Atmospheric pressure is the force per unit area exerted against a surface by the weight of the air above that surface. LNG pressure is typically 25 kilopascals or 3.6 pounds per square inch. As a comparison, air pressure at sea level is 101 kilopascals or 14.7 pounds per square inch.
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  26. LNG spills in port during loading and unloading operations typically involve a small amount of LNG. Such incidents are rare due to the strict procedures and equipment safeguards in place to limit the risk of a spill due to human error (such as overfilling tanks). On the ship, LNG cargo containment systems with double-walled insulated tanks and leak detection systems have proven successful to date in preventing small leaks from becoming larger leaks that reach beyond the confines of the ship.
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  48. This equates to approximately 240 tonnes of greenhouse gas emissions compared with 355 tonnes from a diesel equivalent (93,550 gCO2e/GJ).