Frequently Asked Questions
Liquefied Natural Gas
Liquefied Natural Gas (LNG) is a clear, colourless liquid created when natural gas is cooled down to -162 ºC. In liquid form, LNG takes up around 600 times less volume than ordinary natural gas, making it highly efficient to store and transport. LNG is a good alternative to gas transport by pipeline, particularly for long-distance transport.
LNG is non-toxic and non-corrosive, is completely odourless and is not kept under pressure. Its extremely low temperature means it cannot ignite. When it evaporates and becomes gaseous again, it is just like natural gas from a gas stove. LNG is flammable, however, if it is released into the air after evaporation. LNG can only burn at a specific air-to-gas ratio. This is why legislation and regulations devote considerable attention to prescribing adequate ventilation.
Liquefied Petroleum Gas (LPG) is often confused with LNG and vice versa. LPG (Liquefied Petroleum Gas) consists mainly of propane (C3H8) and butane (C4H10) and is used mainly for domestic and commercial applications (including passenger cars). LPG is kept liquid by maintaining it under high pressure.
LNG is at normal pressure (i.e. normal atmospheric pressure) and is kept liquid at a very low temperature (around -162 ºC). The properties of LPG are very different to those of LNG: natural gas is lighter than air and so it disperses and dilutes rapidly – as opposed to LPG’s components that are heavier than air.
LPG is stored under pressure, while LNG is stored at atmospheric pressure at a very low temperature. This results in the use of very different materials (different material properties, thicknesses, insulations). These differences mean that the procedures and standards for working with LNG differ from those for LPG.
LNG carriers bring the LNG to Gate terminal.
The LNG becomes gaseous again by heating the liquid to ambient temperature. It is then passed to end-users through Gasunie’s pipeline network. Some of the liquid LNG is transported by trucks, barges, coasters and seagoing vessels.
Liquefaction of natural gas is a question of extreme cooling, to over -162 ºC. This takes about 10% of the amount of natural gas that is liquefied. Around 10 m3 of natural gas is needed to liquefy 100 m3 of natural gas. This quantity of natural gas is used directly at the source, which is cost-efficient.
Yes, it can take energy to keep LNG liquid. The liquid heats up and starts to boil. Boiling extracts heat from the liquid and keeps it cold. The boiling gas (BOG, Boil-Off Gas) is captured and emitted. This gas contains a certain amount of energy required to keep LNG liquid. In the event of a high send-out, the BOG is condensed, which does not require any energy.
This does not require any extra energy. The LNG is made gaseous again in a heat exchanger. Such a heat exchanger is actually an inverted heating radiator. The LNG is led through the radiator (heat exchanger), and by increasing the surface area, it absorbs heat from the ambient air through the metal.
At Gate terminal this needs no extra energy. The heat required to reheat LNG and make it gaseous is residual heat from companies in the area, especially Uniper’s power station. If Gate terminal did not use this heat, it would cool down in the cooling water basins in the outside air.
LNG is derived mainly from areas where large quantities of natural gas have been discovered. Among the countries producing LNG are Trinidad, Nigeria, Algeria, Qatar, Indonesia, Malaysia and Australia.
Once it has been made gaseous, the LNG will pass through the gas network to customers in the Netherlands and elsewhere in Europe. Liquefied LNG goes mainly to pumping stations and seagoing and inland navigation vessels in the Netherlands and Northwestern Europe.
A great deal of gas is already being transported by pipeline to the Netherlands from surrounding countries. Liquefied natural gas takes up considerably less volume than in a gaseous state (the required storage space is 600 times smaller!). That enables it to be transported over long distances. This has turned out to be a significant development for countries with large natural gas reserves but without a pipeline infrastructure to a consumer market. Natural gas arising as a by-product of oil production can also be put to good use in this way, where it was previously flared in very large quantities. The expected demand is also tempered by increasing efficiency in the use of gas, for example in households.
- For export from Gate terminal to smaller reception terminals, for example in the Baltic region:
- As bunker fuel for seagoing vessels
- As bunker fuel for inland waterway vessels
- As a fuel for trucks
- By industries that are not connected to the gas network but which nevertheless often use oil or propane as their energy source.
- LNG as a fuel has positive environmental and health effects. The combustion of natural gas produces far less particulate matter, nitrogen, sulphur and other emissions. Instead of diesel, LNG as a transport fuel will have a potential use of two to three million tonnes on the Dutch market in 2030. This leads to the following reductions: up to 25% CO2 emissions, 100% sulphur dioxide, almost 90% nitrogen oxide and 400 to 600 tonnes of particulate matter per year.
- Gas engines running on LNG are quieter than diesel engines. The difference in noise level is so great that trucks that are currently only permitted by day to prevent noise pollution can be used at night for distribution if they run on LNG.
- The standards for sulphur emissions in European and American coastal waters have tightened up since 2015. The Sulphur Emission Control Area (SECA) legislation means newly-built ships must order engines with LNG as fuel. The International Maritime Organisation (IMO) also recently set strict requirements for shipping emissions worldwide.
- Major cost savings can be achieved for shipping fuel consumption, given that 80% of the operational cost for a ship is attributed to fuel. LNG is a cheaper and cleaner fuel.
No, Europe lags behind Asia in this respect. Worldwide, 27.8 million cars now drive on natural gas. Thousands of trucks in China and the US run on LNG, and about five hundred in the Netherlands. Some ten inland waterway vessels use LNG.
The transport sector’s environmental requirements are becoming increasingly stringent. Engines must be cleaner, more economical and quieter, and inland and maritime shipping in the North Sea and Baltic regions must meet strict sulphur standards since 2015.
Although it’s a fossil fuel, using LNG instead of oil-based fuel cuts down directly on emissions. Fossil LNG can be replaced over time by LNG from biomass derived from organic waste streams, or by other forms of renewable LNG. So switching to LNG is part of the transition to a fully sustainable energy supply. In the meantime, LNG as a transport fuel has become a cleaner and more affordable alternative to diesel and fuel oil.
Gate terminal operates independently. This means that parties operating in the gas market can contract throughput capacity in the terminal. These will mainly be long-term contracts for significant volumes of gas per year. Users can be energy companies, but also producers selling their own products.
The functions of the LNG terminal are: supply, a buffer between supply and the continuous delivery of natural gas, evaporation and discharge. At the terminal, LNG is regasified and is pressurised for delivery to the Dutch gas transport network.
Storing LNG occurs in specially designed large-scale ‘full-containment tanks’. These consist of a metal inner tank and a fully concrete outer tank. Thermal insulation between the steel inner tank with LNG and the concrete outer tank limits LNG evaporation to approximately 0.07% of the tank capacity per day.
Gate terminal has three storage tanks, three jetties, three loading bays for trucks and an environment where LNG is converted into natural gas. Gate works on behalf of customers who own the LNG, and it offers the following services:
Reception and unloading
An extensive safety checklist is completed before an LNG ship starts unloading. The liquefied gas is transferred from the ship to the storage tanks via an unloading facility and a pipeline. A vapour recovery system ensures that no under or over-pressure can occur in any of the tanks. This enables the transfer to run efficiently and safely.
Storage and cooling
LNG is stored temporarily in extremely well-insulated tanks. The product can be kept cool by extracting the LNG vapours, causing the tank temperature to drop. These vapours are then added to the gas distributed via the gas pipeline.
Heating and distribution of gas
The LNG is pumped from the tanks and pressurised. It is then heated and regasified and leaves the terminal as natural gas via underground pipelines. These connect to the gas transport network for further distribution to households and industry in the Netherlands and Northwestern Europe.
Loading in small vessels and trucks (‘small-scale’)
Loading cooled LNG into small vessels and lorries for distribution to smaller terminals, fuel stations and larger vessels, where it is used as fuel.
Reloading LNG to large carriers so that Gate customers can deal in LNG on the global market.
Gasunie has operated an LNG peak-shaving facility in the port of Rotterdam for over thirty years and is thus familiar with the LNG product. Vopak offers storage facilities for a range of products, including those needing to be stored at low temperatures or under pressure. Knowledge of LNG and the storage of products is therefore present with the combination of Vopak and Gasunie.
No, Gate terminal’s location was chosen at the time such that the safety of shipping is guaranteed and the LNG ships cause no inconvenience.
The LNG port is separated from the ongoing shipping traffic, constructed in such a way that it can be reached through short, simple manoeuvres. The port of Rotterdam also has modern traffic management (VTS) and a high level of nautical services (pilots, tugboats and boatmen). The port is fully equipped for professional enforcement of the safety standards. Strict safety procedures are applied. As with the transport of other hazardous substances, the government also imposes strict requirements on transporting LNG.
Safety is paramount at every stage of the process at Gate terminal. Gate terminal attaches major importance to both safety and the environment. The partners pursue a strict policy on safety, health and the environment.
Safety can be guaranteed because the LNG industry has been drawing up standard codes since the early 1970s, and takes safety into account when designing the equipment. As a result, the LNG industry has built up an excellent safety reputation. The terminal’s policy is aimed at ‘no harmful emissions’. Natural gas and LNG products are regarded worldwide as energy carriers with a low environmental impact. These products also have a good safety track record.
LNG is liquefied natural gas and, like natural gas from the gas network, is the cleanest fossil fuel available. Using LNG as a fuel in small-scale applications, such as transport or for remote industries, therefore releases less CO2 than oil products, and virtually no nitrogen or particulate matter. It is also a completely sulphur-free fuel. LNG is therefore an affordable and cleaner alternative to oil products.
LNG has been transported by ship since the 1960s, and there have been no serious incidents in all that time. LNG ships must report to the Harbour Master 24 hours prior to arrival and are obliged to take a pilot on board. This applies to all seagoing vessels transporting hazardous substances. The Port Regulations also prescribe, among other things, that only LNG ships may enter the LNG basin. Other vessels are not permitted.
Moreover, the ships are inspected regularly to check whether they still comply with the strict safety standards. Without this regular inspection, the ships are not allowed to load LNG at our transhipment installation.
With a special LNG basin, where only LNG ships and LNG-related ships may enter, the risk of collision is reduced to a minimum. In the fifty years that LNG has been transported by ship, there have never been any serious accidents involving major leaks. Nevertheless, the Environmental Impact Assessment (EIA) examined the possible consequences of an accident.
The Maritime Research Institute (MARIN) in Wageningen has conducted extensive research into the likelihood of an LNG ship colliding on its way to the LNG terminal jetty. The research report is appended to the EIA. The study shows that the risk of a collision is mainly present at the anchorage, in the Eurogeul (both offshore) and when turning into the Beerkanaal and the LNG port. At the berth, LNG leakage arising from a collision is excluded (head-to-head and side-on collisions in the LNG port are highly unlikely). The chance of LNG being released in the vicinity of industry and homes is therefore very small for the surrounding area. It is in the order of magnitude of a maximum of 2.5 x 10-10 per ship, or a chance of 1 in 4 billion.
LNG will evaporate immediately if released, as it heats up in the environment. It does not mix with water, does not float and cannot penetrate into the ground. Before it can burn, it must first evaporate, and the ratio of LNG to air must be just right, namely between 5% and 15% of the air must consist of natural gas. It is non-combustible if there is too much or too little natural gas. Reaching the relevant ratio depends on the weather, among other things. In wind, natural gas evaporates, and the relevant ratio will not occur. In addition, there must be an ignition source. LNG will never ignite spontaneously.
The ships transporting LNG have double hulls, minimising the risk of leakage in the event of a collision. If it should happen and LNG flows into the water, the cold liquid will immediately heat up because of the ambient temperature and the warmer water, and will rise and blow away like a cloud of gas. The LNG will not dissolve or mix with water, but will disappear as a gas, because it is lighter than air. A cloud will be visible around the leak. This is not a cloud of gas, but condensing water vapour from the cold released from the LNG. The flammable natural gas has already risen from this.
The EIA calculates the extent of any effects for various weather conditions in the event of a collision. In the most unfavourable situation, where the gas cloud does not ignite immediately, the effect distance for locations near the Beerkanaal and the Yangtzehaven is almost 1,500 metres. Depending on the direction of the wind, the concentration of gas in the air at that distance is reduced to below the ignition limit. Any cloud of gas will also rise, because gas is lighter than air. This virtually eliminates the downwind risk.
Actions during transhipment are kept to a minimum. Based on procedures and automation, risks are also extremely low.
LNG ships are routed in a separate channel at Gate terminal. This ‘Kleine beer-kanaal’ is not accessible to heavier or larger vessels. There is also a small island, which acts as a natural barrier between the supply route and Gate terminal. Such vessels are guaranteed to run aground, as there is only a depth of 14 metres. There is also the matter of pilotage with well-trained pilots and the use of tugs, so that Rotterdam Port Authority considers the risk of collision to be acceptably low.
The piping for the LNG transport to the tanks is kept permanently cold. After safe mooring, communication is first connected between shore and ship. The loading arms are connected after securing. Once everything has been checked, the arms are cooled so that unloading can begin. In the unlikely event that something should happen, a large number of safety devices have been installed, such as automatic stops on the pumps, and automatic closing of the valves and arms, which have been programmed in case there is a danger of overstretching so that they will break loose dry (i.e. without the release of LNG). Extensive checklists are reviewed in advance. This occurs not just at Gate terminal, but also worldwide.
Yes, using LNG as a transport fuel is absolutely safe. Worldwide, it has long been an accepted fuel for use in trucks, cars and ships. The industry has built up an excellent safety reputation in the more than fifty years that LNG has been used.