Chive Fuels | Frequently Asked Questions

About Chive Fuels

Chive Fuels offers a real solution to the economic and environmental pressures facing the road transport sector, LNG - the cleanest and most economical propulsion fuel for road transport operators.

It is our belief that we can make a worthwhile contribution to the improvement of air quality by providing the means to displace traditionally fuelled vehicles with those powered by natural gas.

Chive Fuels have made LNG available at motorway convenient locations open for public dispensing, and are currently developing a refuelling network that will provide access to natural gas as a vehicle fuel for every haulier - to be able to go everywhere across the UK.

Chive has developed the technology to allow the dispensing of Compressed Natural Gas (CNG) from LNG stations. This has been trialed successfully in Edinburgh, and should demand for light CNG vehicles grow, Chive would be looking to adapt this technology to our refuelling infrastructure.

Chive Fuels also deliver LNG by road for commercial usage.

NATURAL GAS SUPPLIES

Do other countries use natural gas as vehicle fuel?

There are over 4 Million Natural Gas Vehicles (NGVs) in over 50 countries worldwide. The largest NGV markets are currently in Argentina, Italy, Brazil, Pakistan and the USA. Source: Gas Vehicles Report

Where does the UK rank in terms of natural gas production?

The UK is the world's sixth-largest producer of natural gas, and it has an estimated 35 years of reserves. Natural gas reserves are more widely spread than oil, so that many countries have their own supplies, and are thus less dependent on oil imports.

How long has natural gas been around?

Commercially available for over 100 years, natural gas has evolved to become a first class domestic and industrial fuel, and is now available for use as an economical and environmentally safe transportation fuel.

CHIVE FUELS AND NGV DEVELOPMENT

What is Chive Fuels involvement with NGVs?

Chive launched the use of Liquefied Natural Gas (LNG) as a road fuel in the UK, and has delivered fuel to the first LNG Iveco, Dennis Eagle, ERF, Scania, and Foden Dual-Fuel™ vehicles in Europe.

Chive has specialist skills in the design and operation of natural gas vehicles, pioneering the UK introduction of gas powered refuse collection and heavy goods vehicles.

NATURAL GAS

What is natural gas?

Unlike other hydrocarbon fuels (e.g. petrol, diesel and LPG), natural gas consists predominantly of a molecule found naturally in the environment, methane. Natural gas is inherently cleaner than any other fossil fuel and is the cleanest of the "alternative fuels". As a road fuel, it is available as Liquefied Natural Gas (LNG), or as Compressed Natural Gas (CNG). Chive Fuels supplies both LNG & CNG.

METHANE

Methane has the lowest carbon to hydrogen ratio of any fuel, apart from pure hydrogen, and is therefore, second only to hydrogen in terms of the carbon dioxide produced when burned. As fuel producers, we take our responsibility of reducing global warming very seriously. In fact we believe that everyone from corporations to individuals has a duty to reduce the amount of carbon dioxide emissions they produce.

Transport is widely recognized as the fastest growing CO2 producer and we are proud to promote natural gas as an alternative automotive fuel to give everyone the opportunity to make a positive contribution to climate change. A natural gas is predominantly methane CH4, it burns more cleaner than either petrol or diesel fuel and generates significantly fewer carbon dioxide emissions as well. To prevent natural gas 'escaping' into the environment, gas is delivered in sealed tanks, and refuelling takes place via a sealed system.

What is Liquefied Natural Gas?

LNG is simply the liquid form of natural gas. Though a gas at normal temperatures and pressures, it becomes a liquid as the temperature drops in much the same way as steam turns to water when cooled. Natural gas only changes to its liquid form when it is cooled to below minus 160°C, and then, it has to be stored in super insulated tanks. The cryogenic industry, which grown up around such cold liquids, is now mature and has developed well-proven storage equipment and handling procedures.

LNG is carried onboard vehicles in cryogenic tanks that are effectively large thermos flasks consisting of two tanks, one inside of the other, separated by a vacuum. High pressure gas in the void above the liquid gas is drawn off routed through a series of pressure reducers, and eventually fed into the engine at near atmospheric pressure, where it mixed with the appropriate weight of air.

What is Compressed Natural Gas?

CNG represents a convenient form of natural gas that is half way between the gaseous and liquid states. That is to say, for a given volume, it has more energy than the original gas, though not as much as the liquid gas. Natural gas has a low specific energy, and for example, a litre of diesel fuel has as much energy as 1000 litres of natural gas. But if natural gas is compressed to 200 times normal atmospheric pressure - to some 3000 lb/in2, the equivalent storage volume comes down to just five litres. However, if the gas is compressed even more, it eventually liquefies, and the volume decreases yet again, to just two litres. Both LNG and CNG systems provide a rapid fill facility and are pilfer proof.

What is Liquid Petroleum Gas? Is it the same kind of fuel?

LNG and CNG are forms of natural gas whereas, LPG is a by-product of the oil and gas industries. LPG only occurs along with oil deposits, and was for many years 'flared' off and thus wasted. Nowadays it tends to be reused to pressurise the oil deposits and thus maximise the oil extraction. At the same time, LPG is widely used as a feedstock for the petrochemical industry and has, like oil, become an internationally traded commodity. To sustain a major transport market sector, and achieve a long-term future, LPG would need to be synthesised from oil or gas. The energy use involved in the synthesis process and the emissions generated would remove many of the environmental benefits that the use of surplus LPG currently affords.

In any case, LPG is not suited to vehicles above 3.5 tonnes gvw, as it does not provide the required performance. If natural gas is predominantly methane, LPG consists mainly of propane. This, like methane is an excellent fuel, but it tends only to be used only in dual-fuel, LPG/petrol applications where the engine fuelling and therefore combustion characteristics are compromised.

Are LNG and CNG safe fuels?

Health & Safety issues have been the priority in the design and manufacture of the refuelling and vehicle systems. Natural gas is a far safer fuel than diesel or petrol for the following reasons: gas is stored in cylinders which are stronger than thin skin petrol/diesel tanks; several safety features prevent over-pressurisation; natural gas is non-toxic and lighter than air so will rise and disperse if a leak occurs. Natural gas is unlikely to ignite in a road accident situation, having a much higher ignition point than diesel.

NGV OPERATOR BENEFITS

For a quick listing of operator benefits of making the switch to natural gas click here

What is the gap between the price of diesel and cleaner gas fuels?

The general trend of diesel prices to rise is expected to continue and the government is committed to increasing the gap between diesel and the cleaner gas fuels.

EMISSIONS

How do natural gas emissions compare with diesel?

Road vehicles are major contributors to air pollution in the UK. Road transport is responsible for 24 percent of the UK's carbon dioxide (CO2)emissions, 27 percent of particulates (PM10), 49 percent of oxides of nitrogen (NOx) and 75 percent of carbon monoxide (CO) (DETR).

Amongst other effects, these pollutants damage crops and buildings through acid deposition, they contribute to urban smog and global warming and damage the nation's health through respiratory illnesses, particularly in our towns and cities.

Diesel and petrol contain a complex mixture of hydrocarbons (HC) which are reactive in the urban atmosphere and in some cases toxic and, therefore, hazardous to public health. Diesel engines produce significant quantities of particulate matter, or PM10 as it is known. It is becoming increasingly clear that particulates from vehicle exhausts are a major cause of poor air quality in cities and a significant health hazard.

Reduced Noise

NGV engines produce around half the noise of a diesel engine, making for a quieter vehicle. This means that some companies can take advantage by making overnight deliveries into urban centres and other noise sensitive locations. Gas Truck: 60 dB(A); Executive Car: 60 dB(A); Light Van: 64 dB(A); Diesel Truck: 68 dB(A)

SOURCE: BRIAN MCMURRAY - Lambda X

LEGISLATION

Who monitors air quality in the UK?

The government's National Air Quality Strategy requires the monitoring of the airborne pollutants, NOx and PM. The Air Quality Regulations 1997 oblige local authorities to assess local air quality.

How does the UK's clean air legislation compare with that of continental Europe?

UK legislation is encouraging the use of cleaner fuels and moving towards 'polluter-pays' principles, while in continental Europe much of this legislation is already rigidly enforced. In the spirit of setting a good example to private industry, an increasing number of councils are now running gas-fuelled vehicles.

LNG REFUELLING

How is gas delivered?

Chive fuels supplies LNG as a complete package, which includes storage and dispensing equipment. LNG is transported from a central storage depot by tanker to our growing network of motorway refuelling stations and also at dedicated refuelling stations on the customer premises.

How is the Liquefied Natural Gas costed?

Natural gas is sold by the kilogram/or litre. The actual rate charged depends on two factors: Firstly, fuel consumed from our motorway stations is available at a fixed price per kilogram, or for customers with depot LNG stations the rate charged reflects the customer location and the amount of fuel used.

How does the refuelling station work?

All LNG refuelling stations operate on the same 'drive-through' principle of a normal (diesel) service station forecourt. Additionally the station can be expanded to offer dispensing of Compressed Natural Gas (CNG).

How is the gas stored?

LNG is stored at the refuelling site, in super insulated vessels using proven and safe cryogenic (low temperature) techniques. The refuelling station continually monitors itself and makes adjustment to ensure that fuelling of vehicles is problem free

How is gas consumption monitored?

The station's purpose is to make refuelling simple, quick, safe, and reliable, and is able to provide vehicle consumption data for the 'end user' through the use of Triscan dedicated key fob dispensing control technology.

Is it your intention to develop a nationwide refuelling infrastructure with open access?

Chive have made LNG available at motorway convenient locations open for public dispensing, and are currently developing a refuelling network that will provide access to natural gas as a vehicle fuel for every haulier - to be able to go everywhere across the UK

ONBOARD GAS STORAGE

What is the tank on the vehicle like?

The LNG Fuel Tank is a cryogenic container that is designed as two separate pressure vessels, one inside the other. The inner vessel stores the cold LNG in its liquid form, and is wrapped with multiple layers of non-combustible insulation and reflective foil. It is then sealed within the outer vessel. The space between the inner and outer vessels is then evacuated to produce a superior insulation system. The tanks vary in size to suit differing vehicle configurations and individual operating requirements.

What about weight of the tank?

The fuel is stored at a comparatively low pressure (30-150 psi, compared to 3000 psi for CNG) and therefore the weight of the tank is significantly lower than that of a CNG cylinder of comparable volume. LNG has a higher energy density than any other road fuel, and is therefore the optimum solution for heavy vehicles on known and controlled routes where payload is important.

How is gas supplied to the engine?

The LNG fuelling system includes a vaporiser, linked to the engine cooling system, which heats the LNG - thus supplying gaseous fuel to the engine. Additional equipment regulates the gas supply pressure and allows measurement of the fuel level in the tank.

USEFUL CONVERSION FACTORS

On a dedicated gas engine operating at 85 percent efficiency - 1 gallon (or 4.55 litres) of diesel is equivalent to 3.92 kilograms of natural gas.

On a compression ignition (Bi-fuel) engine - 1 gallon (or 4.55 litres) of diesel is equivalent to 3.4 kilograms of natural gas.

Fuel Storage Pressures and Temperatures Diesel and Petrol are stored at 1 bar @15 deg C. By comparison: LPG is stored at 8 bar @ 15 deg C; LNG is stored a 5 to 7 bar @ minus 160 deg C, CNG is stored at 200 bar @ 15 deg C.

Gas and Cylinder Weights The typical weight of a 52 gallon tank when full to capacity is 180 kilograms. The typical weight of a 95 gallon tank when full to capacity is 365 kilograms.

CHIVE'S ROLE IN THE SWITCH TO NATURAL GAS

What help does Chive Fuels give operators who want to switch to natural gas?

Chive provides operators with ongoing practical advice and support: from applying for a Powershift grant, through to the design and installation of the refuelling equipment. The refuelling facility is paid for by Chive. Customers simply pay for the fuel that they use.

Chive Fuels is committed to continuing to nurture an important network of suppliers and partners to ensure the development of the industry and delivery of the customer value proposition.