This is a working document and is undergoing regular updates and elaborations. The aim is to produce a reference documenting the different gases used within past and present energy systems.
‘Blue Water’ Gas
A form of coal gas (see coal gas) that was formed by introducing steam into the manufacturing process. It often had a lower calorific value than other forms of coal gas. In the UK, it was introduced as a technique for gas production in the 1900s.
Typically a by-product of natural gas processing, propane is often referred to as LPG (see LPG). It has four carbon atoms and ten hydrogen atoms. It is most commonly used for heating and cooking and as a vehicle fuel.
Compressed Natural Gas. Natural gas that is compressed to less than 1% of its typical volume at standard atmospheric pressure. After compression, it is stored and transported within pressure vessels (typically, canisters). It is primarily used in Asia as a transport fuel.
Any manufactured gas produced from the combustion of coal in a retort denying it access to oxygen. The production of coal gas would often result in the production of numerous by-products, including coke, bitumen and ammonia. The calorific value of coal gases could vary considerably, depending upon the manufacturing process used.
A term for the natural gas found within (particularly coal) mines. Also known as ‘mine gas’ (see mine gas), although a range of gaseous atmospheres were also commonly associated with mines, including concentrations of ‘choke damp’ (carbon dioxide) and ‘white damp’ (carbon monoxide). Typically, fire damp was considered a dangerous nuisance, causing large numbers of fatalities and the closure of mine workings. In a few rare instances however, fire damp was used for lighting individual properties.
Hydrogen is an element, consisting of a single atom. As a flammable gas, it appears as a molecule, consisting of two connected hydrogen atoms. It is current
Liquefied Natural Gas. Natural gas that has been compressed and reduced in temperature to the point at which it changes state, from gas to liquid. In the process, it reduces in volume to 1/600th of its volume at standard atmospheric pressure. This makes its long-distance transport more economically viable, as more gas can be transported in the same space. It is used to supplement existing supplies of natural gas within pipeline systems – it is typically transported by boat and lorry tanker, and is regassified prior to injection into a natural gas pipeline. LNG that is transported long distances will also often have to have nitrogen (an inert gas) added to it before it can be transported by pipe, as lighter alkanes will ‘boil off’ as the gas slowly warms over time, leaving a more energy rich gas consisting of higher-value alkanes).
Liquefied Petroleum Gas. LPG can be one of two gases; propane or butane. It is typically stored and transported in cylinders and is commonly used for heating and cooking services, particularly within island energy systems. It has a higher calorific value by volume than CNG, meaning that its import/export is often more economical. It is also widely used as a vehicle fuel.
The main component of natural gas, consisting of four hydrogen atoms attached to a single carbon atom. It is an odorless, invisible gas with a high energy content.
A term for the natural gas found within (particularly coal) mines. In the 1700s and 1800s this material was more commonly referred to as ‘fire damp’ (see fire damp). Typically, mine gases were considered a dangerous nuisance, causing large numbers of fatalities and the frequent closure of mine workings. In a few rare instances however, mine gas was used for lighting individual properties.
A term for any manufactured gas that was distributed through a pipeline network owned by a municipality.
A broad term for any manufactured gas that was produced from oil products. The calorific value of oil gases could vary considerably, depending upon the manufacturing process. In the UK, oil gas became increasingly used between the 1950s and 1980s, as the price and availability of coal fluctuated.
Typically a by-product of natural gas processing, propane is often referred to as LPG (see LPG). It has three carbon atoms and eight hydrogen atoms. It is most commonly used for heating and cooking and as a vehicle fuel.
A form of gas named after a manufacturing process first established on the Isle of Grain, in the South East of England (South East Gas). Segas became a popular method of gas production in the 1950s and 60s, mainly because it could produce gas from a wide variety of oil feedstocks and because its start-up time was short.
A popular term for any manufactured gas that was distributed through a ‘town gas’ network. Such networks involved one or more gasworks (sites of gas manufacture) from which a network of distribution pipes spread, and through which gas was delivered to residential and commercial properties across a set ‘local’ area.