UNIT 1 NATURAL GAS IN THE TRANSPORTATION SECTOR

NATURAL GAS IN THE TRANSPORTATION SECTOR

Natural gas has long been considered an alternative fuel for the transportation sector. In fact, natural gas has been used to fuel vehicles since the 1930s! According to the Natural Gas Vehicle Coalition, there are currently 150,000 Natural Gas Vehicles (NGVs) on the road in the United States today, and more than 5 million NGVs worldwide. In fact, the transportation sector accounts for 3 per cent of all natural gas used in the United States. In recent years, technology has improved to allow for a proliferation of NGVs, particularly for fuel-intensive vehicle fleets, such as taxicabs and public buses. However, virtually all types of NGVs are either in production today for sale to the public or in development, from passenger cars, trucks, buses, vans, and even heavy-duty utility vehicles. Despite these advances, a number of disadvantages of NGVs prevent their mass production. Limited range, trunk space, higher initial cost, and lack of refueling infrastructure pose impediments to the future spread of NGVs. Most NGVs operate using compressed natural gas (CNG). This compressed gas is stored in similar fashion to a car's gasoline tank, attached to the rear, top, or undercarriage of the vehicle in a tube-shaped storage tank. A CNG tank can be filled in a similar manner, and in a similar amount of time, to a gasoline tank.

C Reducing carbon-monoxide emissions

There are many reasons why NGVs are increasing in abundance and popularity. New federal and state emissions laws require an improvement in vehicle emissions over the foreseeable future. For example, the state of California has some of the most stringent environmental standards, many of which are currently unattainable with conventionally fueled vehicles. Natural gas, being the cleanest burning alternative transportation fuel available today, offers an opportunity to meet these stringent environmental emissions standards. In addition, natural gas is very safe. Being lighter than air, in the event of an accident, natural gas simply dissipates into the air, instead of forming a dangerous, flammable pool on the ground like other liquid fuels. This also prevents the pollution of ground water in the event of a spill. Natural-gas fuel storage tanks on current NGVs are stronger and sturdier than gasoline tanks.

Natural gas is also an economical alternative to gasoline and other transportation fuels. Traditionally, NGVs have been around 30 per cent cheaper than gasoline vehicles to refuel, and in many cases the maintenance costs for NGVs are lower than traditional gasoline vehicles. In addition to being economical, many proponents of NGVs argue that a transportation sector more reliant on domestically abundant natural gas will decrease the US dependence on foreign oil-allowing for a more secure, safer energy supply for the country.

A The advantages of NGVs

One of the primary reasons for pursuing alternative-fueled vehicle technology is to decrease environmentally harmful emissions. It is estimated that vehicles on the road account for 60 per cent of carbon monoxide pollution, 29 per cent of hydrocarbon emissions, and 31 per cent of nitrogen oxide (NOx) emissions in the United States. All of these emissions released into the atmosphere contribute to smog pollution, and increase the levels of dangerous ground-level ozone. Vehicles also account for the emission of over half of all dangerous air pollutants, and around 30 per cent of total carbon emissions in the US, contributing to the presence of "greenhouse gases" in the atmosphere. The environmental effects of NGVs are much less detrimental than traditionally fueled vehicles. NGVs are much cleaner burning than traditionally fueled vehicles due to the chemical composition of natural gas. While natural gas is primarily methane, gasoline and diesel fuels contain numerous other harmful compounds that are released into the environment through vehicle exhaust. While natural gas may emit small amounts of ethane, propane, and butane when used as a vehicular fuel, it does not emit many of the other, more harmful substances emitted by the combustion of gasoline or diesel. These compounds include volatile organic compounds, sulfur dioxide, and nitrogen oxides (which combine in the atmosphere to produce ground-level ozone), benzene, arsenic, nickel, and over 40 other substances classified as toxic by the EPA. Dedicated NGVs also produce, on average, 70 per cent less carbon monoxide, 87 per cent less non-methane organic gas, and 87 per cent less NOx than traditional gasoline-powered vehicles.

D Who uses NGVs?

NGVs as they exist today are best suited for large fleets of vehicles that drive many miles a day. Taxicabs, transit and school buses, airport shuttles, construction vehicles, garbage trucks, delivery vehicles, and public works vehicles are all well suited to natural-gas fueling. Because these vehicles are centrally maintained and fueled, it is economical and beneficial to convert to natural gas. The primary impediments to the public proliferation of NGVs include the high initial cost, limited refueling infrastructure, and automobile performance characteristics. NGVs, despite being cheaper to refuel and maintain, are more expensive initially than their gasoline powered counterparts. However, as the technology becomes more advanced, the cost of manufacturing these vehicles should drop, which may then be passed along to the consumers.

In terms of refueling infrastructure, there are currently around 1,500 natural-gas refueling stations in the US, over half of which are open to the public. Although this is a small fraction of the number of gasoline-fueling stations in the country, as environmental standards and government incentives for NGVs increase, supplying Natural gas as a vehicular fuel will become increasingly common. While driving range, storage space, and initial cost are currently preventing the mass production of dedicated NGVs (which in turn is preventing the expansion of public natural-gas fueling stations), it is expected that with improved technology, research, and infrastructure, the use of NGVs in non-fleet settings will increase in the future. NGVs present an exciting opportunity to reduce the damage of one of our most polluting sectors

Choose the best heading for each of the sections in the article in Exercise 6 (1-3). There are two headings you will not need.

A.    A The advantages of NGVs

B.     B The need for change

C.     C Reducing carbon-monoxide emissions

D.    D Who uses NGVs?

E.     E An expanding refueling infrastructure

Vocabulary Builder

Conventional	Maintain our present lifestyles	Spend a high proportion of your income
Greener	Gas-guzzling four-by-fours
Make up the shortfall	Face stark choices
Goes without saving	Get us out difficult situation

Match the words or expressions from the article (1-9) with words or expressions that have a similar meaning (a-i).

1	proliferation	E	great increase
2	impediments	C	barriers
3	attached	B	fixed
4	foreseeable future	G	soon
5	stringent standards	I	Strict recruitments
6	unattainable	F	Out of reach
7	in the event, of	H	If this happen
8	detrimental	A	harmful
9	primary strict requirements	D	main

non-renewable energy resources	renewable energy resources
coal, fossil fuel, gas, peat	biofuel, biomass, ethanol, hydroelectric power, nuclear power, solar power, tidal energy, wind power

Spotlight on language

Coal, oil, nuclear

1	Robert's a bright spark - he'll a release (nervous) energy know the capital of Mongolia.	f	an intelligent person
2	Andrea 's full of beans this morning.	c	has a lot of energy
3	Do you really think we can sell our cars in Japan? It's like taking coal to Newcastle.	g	supplying something where it is not needed
4	After a tough day at work in the office, Ruth loves to let off steam with a game of squash.	a	release (nervous) energy
5	There are six months before my IELTS test, so from now on, it's full steam ahead.	b	time to go at top speed
6	Steffi has been burning the midnight oil for the last two weeks.	d	working late at night
7	Derek is already in a bad mood. Don't tell him about the broken photocopier right now. That will just be adding fuel to the fire.	e	making a bad situation worse.

These words occur in pairs including modifiers intensifiers in the text. How many pairs can you remember? Now check the text to see if you were right.

almost certainly dangerous highly likely far no ever more probable quite too way

1.      too dangerous paragraph 1

2.      no way paragraph 2

3.      ever more paragraph 3

4.      almost certainly paragraph 3

5.      quite probable paragraph 4

6.      highly likely paragraph 5

Choose the best words

1.      Working in a coal mine extremely/ totally dangerous job.

2.      People who work on oil rigs are generally very so well paid, but they do work incredibly/ definitely.

3.      Many people in Germany are totally/ ever opposed to nuclear power

4.      Putting solar panels on the roof of your house is relatively/wholly easy

5.      If you live in a country and don’t insulate your house properly, your energy bills are likely to be certainly/quite high.