Unlimited access to Natural Gas market reports on 180 countries. Tap into millions of market reports with one searc Leading Online Gas Log Selection. Call for Expert Advice. Order Your Gas Logs Today! Realistic Natural Designs and Superior Performance Natural gas is a fossil fuel, though the global warming emissions from its combustion are much lower than those from coal or oil. Natural gas emits 50 to 60 percent less carbon dioxide (CO 2) when combusted in a new, efficient natural gas-power plant compared with emissions from a typical new coal plant • Coal vs. Natural Gas-The impacts and improvements • Final verdict . Global Energy Demand Is Growing! • Global energy demand grew by 8% from 2008- 2012 • Demand projected to increase by 37% by 2040 • Development of renewables is being outpaced by energy demand growt All may be considered fossil fuels, but they differ in time and conditions of formation and chemical composition. Coal is a solid, oil is a liquid and natural gas is a vapor (gas). Coal and oil form from deposits of animal and vegetable matter deep in the ground at conditions of high pressure over many years. Natural gas is also formed during those processes, but it can also be generated.
Burning natural gas, for instance, produces nearly half as much carbon dioxide per unit of energy compared with coal. Natural gas is thus considered by many to be a bridge fuel that can help. However, natural gas does more to contribute to global warming than do coal, gasoline, and diesel. Far more in fact. Methane is the reason natural gas does so much harm with respect to global warming. There are two reasons why. First, natural gas is methane. Conditioned natural gas is between 85 and 85 percent methane . The basic hydrocarbon structure is Cn H2n+2. So the simplest hydrocarbon is CH4. It is methane and is the main constituent in natural gas. Nat.. Coal has the approximate chemical formula CH. Natural gas is the best fossil fuel in terms of energy output per unit carbon dioxide emitted. Biomass is renewable because a new crop can be grown after each harvest, and biomass is a low carbon fuel Gas vs Coal. The CO2 emissions from Natural Gas Combined Cycle (NGCC) plants are reduced relative to those produced by burning coal given the same power output because of the higher heat content of natural gas, the lower carbon intensity of gas relative to coal, and the higher overall efficiency of the NGCC plant relative to a coal-fired plant (1)
There is also a minor difference in the flavor imparted by combustion gasses, the volatile byproducts given off by the burning of the charcoal or the gas. When propane combusts it makes more steam than charcoal, and some say that keeps meat moist giving gas an advantage Here's our quick oil and gas glossary to help you sort your coal bed methane from your LNG. Natural gas: Natural gas is a major energy source around the world, accounting for 21 per cent of the world's energy supply in 2010. Natural gas is an odourless, colourless gas, largely formed over millions of years underground Coal and natural gas with carbon capture and storage (CCS) and use (CCU) have been advertised as zero-carbon sources of electric power that should be implemented as solutions to global warming, air pollution, and energy security. Natural gas has also been proposed as a bridge fuel between coal and renewables. This section evaluates these claims Natural gas has increased from 15% to over 30% of overall United States energy production in that same time period. Because natural gas burns cleaner than coal, this shift to more gas than coal combustion for U.S. energy has without a doubt been a factor in the reduction of carbon being pumped into the atmosphere Unlike natural gas, emissions from coal and oil can cause acid rain, which is formed when sulfur dioxide and nitrogen oxides react with hydroxyl radicals in the environment. Acid Mine Drainage. Another impact of coal mining and extraction on regional water quality is the runoff--called Acid Mine Drainage (AMD)--from active and retired coal.
Therefore, Coal and Hydrocarbons differs significantly in their Chemistry; Hydrocarbons (contains C and Hydrogen Only) while Coal (contains other variables elements). 6 Page 2 of 9 Let us consider briefly the chemical difference of Coal and Hydrocarbons (Crude oil and Natural gas) 2.1 Natural gas is a mixture of lightweight alkanes With pipeline gas projects, it's relatively rare for CO 2 to be removed prior to transportation to market due to cost. As such, the contaminating CO 2 is then emitted when the natural gas is burnt in the consuming market and therefore is not considered part of the upstream emissions.. While the levels of carbon emissions associated with LNG production are significantly higher than those for.
Coal Seam Gas Explained CSG in summary Coal seam gas, also commonly referred to as CSG, is natural gas. It is the same natural gas (Methane) that is piped through the gas mains that go to many Australian homes and businesses.; In fact, coal seam gas is also known as coal bed Methane, as it is extracted from coal seams that are typically 300 to 1000 metres below the surface Crude oil, natural gas and coal are fossil fuels. Fossil fuels are very precious resources because they are non-renewable (once they're used, that's it!). We can also make lots of organic chemicals from them, needed to make products such as paints, detergents, polymers (including plastics), cosmetics and some medicines Shale, tight and coal seam gas are types of natural gas identified by the geology of the underground area where the gas is sourced such as tight sandstone, shale and coal seams. Most of Australia's coal seam gas developments are found on the east coast and none are found in Western Australia. The most significant difference between shale gas. Difference Between Crude Oil and Natural Gas Crude Oil vs Natural Gas Crude oil and natural gas are fossil fuels that are used for heating. They are both formed from the remains of dead plants and animals. Both oils have similar uses but may differ in the effect and outcome of their use. Crude oil, or petroleum, is a flammable liquid that [
1 short ton (2,000 pounds) of coal (consumed by the electric power sector) = 18,875,000 Btu; 1 kilowatthour of electricity = 3,412 Btu; Examples of converting energy sources in different physical units to Btu Example 1: You have a natural gas furnace in your home that used 67,000 cubic feet of natural gas for heating last winter Difference Between Oil and Natural Gas Oil vs Natural Gas Today's world runs on fossil fuels. While strides are being taken to incorporate more renewable energy sources, such as solar and wind power, for the most part the fossil fuel triumvirate runs the world. Coal, oil, and natural gas are absolutely essential to our modern lifestyle. Coal is by far the [ . Electricity prices vary broadly around the country, based on the variety of electricity generation sources, which include natural gas, coal‑fired power plants, nuclear plants, diesel, and renewable. Crude Oil vs Natural Gas Crude oil and natural gas are fossil fuels that are used for heating. They are both formed from the remains of dead plants and animals. Both oils have similar uses but may differ in the effect and outcome of their use. Cru..
The differences between natural gas and propane can be confusing. Especially because propane is one of the fuels that make up natural gas, the other fuels being butane, methane, ethane. While propane is a part of natural gas , it becomes a unique source of fuel on its own when it's separated during processing I'll tweak Dennis Leppin's answer a little. Shale gas is similar to gas from conventional rocks, which exists in the gas phase at pressure inside the porosity. Most shale reservoirs are actually grading toward silty sands, and are not true shales...
. Eventually, if the rocks above it are eroded so that it is exposed at the Earth's surface, the coal itself may be eroded away, and either eaten by bacteria, or buried in new rocks. And, occasionally, a natural forest fire or a lightning strike may set coal on fire In a compressed form, natural gas can also be used as a transportation fuel. Natural gas is either found mixed in oil or is released from coal. Energy in 6,000 cubic feet of natural gas is equivalent to one barrel of oil. World reserves of natural gas are greatest in Russian, Iran, Qatar, Saudi Arabia, United Arab Emirates, and the U.S
. Start studying Chapter 11: Oil, Natural Gas, and Coal. Learn vocabulary, terms, and more with flashcards, games, and other study tools Compare and contrast the combustion of natural gas, petroleum, and coal. How do different fossil fuels compare based on CO 2 emissions? How can we determine which fossil fuel results in less pollution? Explain the difference between methane and carbon dioxide, both chemically and as it relates to their potential to impact global climate The historical gas industry includes two chemically distinct flammable gasses. These are natural gas and several variations of manufactured coal gas. Natural gas is composed primarily of methane, a hydrocarbon composed of one carbon atom and four hydrogen atoms, or CH4. As a fossil fuel, natural gas flowing from the earth is rarely pure
The fall and winter of 2010-2011 compared to 2011-2012 as well as the spring and summer of 2011-2012 show how the relationship between natural gas prices and coal prices can affect natural. Coal seam gas, or coal bed methane (CBM, is a form of natural gas, typically extracted from coal seams at depths of 300-1000 metres. It is a colourless, odourless, non-toxic mixture of a number of gases but mostly made up of methane (generally 95-97 per cent pure methane). Coal seam gas has been part of Australia's energy mix since it was first. The key difference between biogas and natural gas is that the biogas is a renewable source of energy whereas the natural gas is a non-renewable source of energy. Biogas is a naturally occurring gas that forms from the breakdown of organic matter in the presence of anaerobic bacteria while natural gas is a naturally occurring gas that forms from the fossils
The larger columns in panels (b) and (c) reflect the all-coal case and are labeled with their mean values, while the smaller columns reflect the all-gas case; values for the latter are not shown because they are all simply a factor of about 10 lower (reflecting the order-of-magnitude difference between the mortality factors for coal and gas) Wind energy is indeed cost-competitive with natural gas but only with subsidies. According to the official EIA's estimation the cost of a new onshore wind installation is at 9.7 cents per kilowatt-hour, while a natural gas plant has costs at 6.3 cents per kilowatt-hour 3.2 Pr oven re serves of natural gas and coal. Surveys have shown that proven reserves of dom estic natural gas are 12.7x10. 6. million-ft. 3. It is estimated that t he consumpti on rate for. Natural gas is cleaner and greener . Environmental impact is another important consideration when choosing fuels. As you can see in (Table 5) below, the significant differences between natural gas and electricity make natural gas the better choice for the environment. Table
The coal floor is the price at which electrical utilities shut down coal plants and increase use of natural gas fired power plants. In this article I will examine the connection between natural gas prices and those of oil and coal from a variety of angles $482 million for a natural gas plant; As you can see, there's not a huge difference between solar and the average coal plant (natural gas is another story though and, in fact, many new power plants are natural gas powered) Coal, petroleum, and natural gas are called fossil fuels because they have been theorized to have once been fossilized plant matter. A chemical difference between natural petroleum and known decomposition products of biological matter is that geologists have found metals in crude oil such as vanadium and mercury that are poisonous to life It is estimated that if the CPP were to take effect in the reference case, natural gas power generation could account for more than double the amount of power generation from coal by 2040, whereas without the CPP the difference between coal and natural gas consumption is projected to be half this amount Coal seam gas (CSG), also known as coal bed methane, is a form of natural gas typically extracted from coal seams at depths of 300-1,000 metres. CSG is a mixture of a number of gases, but is mostly made up of methane (generally 95-97 per cent pure methane)
There are many byproducts of natural gas processing like ethane, propane, butane, pentane, and other hydrocarbons with higher weights. These gases are used in our day to day life in many forms like CNG, LPG, etc. The facts about CNG, LPG as well as the difference between CNG and LPG is very interesting to know Batteries Low Costs of Solar Power & Wind Power Crush Coal, Crush Nuclear, & Beat Natural Gas. These are 5 messages that I think anyone wanting a better US economy (or a better economy in. Substituting gas for coal does reduce emissions, but there is still far too much carbon in natural gas to allow its widespread use if the electric system is to reduce its emissions by 80 percent by 2050. That was the national goal endorsed by President Obama when he ran for president in 2008
The United States is a domestic producer of natural gas, whereas oil often comes from countries that hate us. That natural gas is relatively cheap is a side benefit. Natural gas use produces less greenhouse gas than coal or oil, explaining why a number of oil and coal plants have been converted to natural gas. While wind and solar power is. The natural gas industry is on an aggressive public relations tear to convince Americans that for decades to come, it is the bridge between coal and renewable energy.The campaign is loaded with disinformation. The American Petroleum Institute (API) says it's pushing gas as a foundation for the future because it is clean The volume of oil and natural gas within a formation before the start of production is the original oil and gas in-place. As oil and natural gas are produced, the volumes that remain trapped within the rocks are the remaining oil and gas in-place, which has the largest volume and is the most uncertain of the four resource caetgories Coal dropped 13%. And natural gas generation, the cornerstone of the Texas grid, plummeted 25% over that six-hour period. The differences point to some of the key failures that have forced the. Examples are coal, gas, crude oil, Mineral resources (limestone, iron, copper, aluminum), etc. Difference between exhaustible and inexhaustible resources. Are natural gases exhaustible or inexhaustible? Natural gas is example of fossil fuel, and all fossil fuels are exhaustible and non-renewable
Coal. Clean Coal Technologies. the differences between diesel and natural gas generators is no longer so clearly defined. ensures the contest between diesel and natural gas generators will. The result is one of three energy sources -- coal, petroleum or natural gas. Natural gas -- historically considered the cleanest of the three -- mainly consists of methane and takes the form of an odorless gas trapped between shale rocks. In the United States, almost 25 percent of our energy usage comes from natural gas. It's mainly used in. Coal is a flammable black or brown organic sedimentary rock. It's mostly carbon and is typically found as layers (coal beds) or veins (coal seams). Natural gas is a combustible mix of hydrocarbon gases. It's colourless and consists mainly of methane (CH4) Coal has the approximate chemical formula CH. Natural gas is the best fossil fuel in terms of energy output per unit carbon dioxide emitted. Biomass is renewable because a new crop can be grown after each harvest, and biomass is a low carbon fuel Petroleum and natural gas are nonrenewable sources of energy.; Petroleum is a liquid mixture found underground that can be used to make gasoline, diesel fuel, and many other products.. Petroleum is also called crude oil or oil.; Natural gas is a mixture of gases - mostly methane.Natural gas is sometimes just called gas. Natural gas is found underground with petroleum
Natural gas, marketed as a clean energy source, actually burns half as dirty as coal when it comes to carbon emissions. An electric dryer powered by electricity generated by rooftop solar panels is greener and cheaper by far than a natural gas dryer — once you buy the solar panels, that is Difference Between CNG and LPG. The main constituent of CNG is methane gas, whereas the main constituents of LPG are propane, butane and other lighter hydrocarbon gases. The sources of CNG is coal bed methane wells and natural gas wells. In case of LPG, the main sources are natural gas fields and crude oil refineries of petroleum Reforming low-cost natural gas can provide hydrogen today for fuel cell electric vehicles (FCEVs) as well as other applications. Over the long term, DOE expects that hydrogen production from natural gas will be augmented with production from renewable, nuclear, coal (with carbon capture and storage), and other low-carbon, domestic energy resources The NY Times indicated that the gap between gas and oil prices was expected to continue to widen. Propane gas: $2,723; Heating oil: $2,383; Electric heat: $1,337 [Note that this figure will vary widely by variation in area electricity rates] Natural gas: $951. [Note that natural gas is not available to homes located in rural and many other areas The most obvious and the fundamental difference between biofuel and fossil fuel is that the first is a renewable energy source while the latter is a non-renewable energy source. However, before delving further into the difference between biofuel and fossil fuel, let us first look at each fuel separately
The glut of natural gas unleashed by hydraulic fracturing - and the resulting low prices - make it seem like a no-brainer: Ditch coal-fired electric plants, with all their baggage about air. The significant difference between charcoal and coal is that coal is a naturally occurring fossil fuel, while charcoal is not. Charcoal is made from the element carbon, and carbonic compounds are plentiful in plants, animals, and other living organisms There's a big difference between being coal free and being carbon free, Smith said. Natural gas is a viable bridging technology in the short term, he said. Nuclear is very economical, and.
Nationwide household consumption of natural gas, liquefied petroleum gas, and fuel oil totaled 5.22, 0.46, and 0.45 quadrillion Btu, respectively, in 2019 (EIA 2020a). Averaged across households in the United States, this amounts to 41,712 cubic feet of natural gas, 42 gallons of liquefied petroleum gas, and 27 gallons of fuel oil per home Thus, coal is known as a non-renewable natural resource this because when coal is mined out and used it cannot be reproduced or re used. What is the main difference between Charcoal and Coal? coal is one of the naturally resulting fossil fuels, while on the other hand charcoal is formed by slow burning of carbon woods It also allows the company to take advantage of the price difference between coal and natural gas. Customers save when the company can lower its overall fuel costs. At the Rogers Energy Complex, the company is pursuing co-firing up to 40 percent natural gas at unit 5; and 100 percent at unit 6
All are fossil fuels which means that they were formed from plants and animals from millions of years ago. Coal is a solid. It is mostly carbon. It is made from mostly plant materials. Natural gas. However, deep decarburization of the power sector would likely require a radical shift from fossil fuels, including natural gas. It's coal vs. natural gas in the fight for Least Negative Impact.
Watch the following video to learn about: -The pros and cons of coal, oil and natural gas -The relative CO2 emissions of each fuel -Applying this in.. The gas accumula- tion abundance is generally high in the sand bodies adjacent to concentrated coal measure source rocks, for instance, the re- serve abundance of the Xu6 Member gas reservoir in the Guang'an gas field averages 3.92Ã—10 8 m 3 /km 2 ; in contrast, the areas, where reservoirs are good in physical property but not in rich coal. Natural gas; Coal; Oil; These distinctions may seem cut-and-dried, but there are some gray areas. Natural gas is often labeled as clean power because it burns cleaner than coal. Folks may even believe that natural gas is a sustainable resource. Don't be fooled. natural gas is a fossil fuel that emits CO2 when burned Natural Gas Fired Power Plants. Natural Gas fired (including LNG fired) power plants account for almost 20 % of the world's electricity generation. These power plants use Gas Turbines or Gas Turbine based combined cycles. Gas turbines in the simple cycle mode, only Gas turbines running, have an efficiency of 32 % to 38 %
Natural gas is similar, although it is burned in something more like a jet engine, but still connected directly to a generator. Coal, our most common fuel source for electricity, is used differently Coal, oil, and natural gas are the usual distinctions, but there's also unconventional oil (such as the Alberta tar sands) and unconventional gas (such as shale gas from fracking). Unconventional means that the fuel is produced in a roundabout way that's less efficient and takes more energy than regular fuel In the USA, around 30% of all energy produced comes from natural gas, whilst roughly a third of this is now obtained by fracking. In comparison, 41% of energy comes from coal burning - a practice deemed by many to be much more harmful to the environment Think about taste. Gas barbecues rely on heat distributing materials which work to vaporise drippings and cause a delicious smoke. Gas devotees will tell you that this produces a flavour just as fine as charcoal, but then it does not explain why people make a great deal of money supplying packs that you just burn on a gas barbecue to try to create a far more woody flavour To calculate energy prices under the adjusted correlation, we define the maximum deviation from the prices found under the perfect correlation as 12.5% of the difference between the upper and lower price ranges of natural gas, coal, biomass and plastic waste. 12 This means that the energy prices determined for the perfect correlations need to.
Natural gas is a fossil fuel.Like other fossil fuels such as coal and oil, natural gas forms from the plants, animals, and microorganisms that lived millions of years ago. There are several different theories to explain how fossil fuels are formed. The most prevalent theory is that they form underground, under intense conditions forms of renewable energy. The range between the studies is illustrated within the figure. Technology Mean Low High tonnes CO 2 e/GWh Lignite 1,054 790 1,372 Coal 888 756 1,310 Oil 733 547 935 Natural Gas 499 362 891 Solar PV 85 13 731 Biomass 45 10 101 Nuclear 29 2 130 Hydroelectric 26 2 237 Wind 26 6 12 Natural gas is better for the environment than other fossil fuels. While natural gas is not as clean as solar or wind energy, it is the cleanest fossil fuel energy source available. According to the Florida Natural Gas Association, 3,000 pounds of carbon dioxide are kept out of the atmosphere for each home that uses a tankless water heater in. Natural gas, solar and wind are costs of renewable energy and persisting cheap natural gas are outweighing the economics of coal and the average difference between the least cost option. All may be considered fossil fuels, but they differ in time and conditions of formation and chemical composition. Coal is a solid, oil is a liquid and natural gas is a vapor (gas). Coal and oil form from deposits of animal and vegetable matter deep in the ground at conditions of high pressure over many years. read mor
Because the reference and high natural gas price projections from AEO2019 are rising over time, the LCOE of new natural gas plants can increase over time if the gas prices rise faster than the capital costs decline. For a given year, the LCOE assumes that the fuel prices from that year continue throughout the lifetime of the plant The biggest difference between Crude Oil and Natural Gas is their molecular makeup. Crude Oil is comprised of a wide and diverse selection of complex hydrocarbons. Because of its unique and complex makeup, Crude Oil comes in many different forms and its viscosity and volatility can vary widely Coal is a solid. It is mostly carbon. It is made from mostly plant materials. Oil is a liquid. It is a mixture of hydrocarbons. It is more animal materials. Its composition is different depending on where it is found. Natural gas is a gas. It is mostly methane, CH4 The primary difference between steam and gas turbines is the fact that steam turbines receive power from expanding steam. Fuels such as natural gas can heat condensed water in a boiler, but it's also possible to utilize renewable thermal energy for this heating Fossil fuels (coal, oil and natural gas) are still essential for transportation, electricity generation, heating, plant operations, and so much more. But they are also the main source of CO 2 emissions and, unlike renewable energies, are produced from exhaustible - albeit still vast - reserves
Coal, crude oil, and natural gas are all considered fossil fuels because they were formed from the fossilized, buried remains of plants and animals that lived millions of years ago. Because of their origins, fossil fuels have a high carbon content The levelized cost of energy (LCOE) is a measure of a power source that allows comparison of different methods of electricity generation on a consistent basis. The LCOE can also be regarded as the minimum constant price at which electricity must be sold in order to break even over the lifetime of the project. This can be roughly calculated as the net present value of all costs over the.
Natural gas trading terminology is different than other markets. When quoted by a trader, the price is the difference between the Henry Hub price and that location's price, called the basis price. Historic differences between fuel oil and natural gas can help consumers develop a general idea with respect to cost differences. Historic Natural Gas, Fuel Oil, and Propane Prices From 2005 to 2018, the price of natural gas has fallen from a high of $18.51 per million Btu to an average of around $3.00 since late 2016 A carbon price and a tax on a fuel both discourage the use of fossil fuels, but there are some differences in how the fees are applied. The Carbon Price slider places a fee on fuels depending on the amount of carbon dioxide they release when burned, while the Coal, Oil, Natural Gas, and Bioenergy sliders adjust the cost of producing the fuels themselves Natural gas is a hydrocarbon gas consisting mainly of methane with varying amounts of alkanes with a small percentage of nitrogen, carbon dioxide, hydrogen sulfide and sometimes helium. Along with petroleum they are found in deep underground rock formations and form part of hydrocarbon reservoirs in coal beds and methane clathrates Crude oil and natural gas are both energy commodities. As such, we use these fuels to heat and cool our homes or supply other energy needs. The price relationship between crude oil and natural gas is an inter-commodity spread, in which the prices between the two change in relation to each other
The difference between HHV and LHV definitions causes endless confusion when quoters do not bother to state the convention being used. since there is typically a 10% difference between the two methods for a power plant burning natural gas. For simply benchmarking part of a reaction the LHV may be appropriate, but HHV should be used for overall. In terms of environmental impact, what's the difference between natural gas, coal, and biomass. Answers: 3 Get Other questions on the subject: Chemistry. Chemistry, 22.06.2019 14:30, clemsongirl5392. Select all that apply. using a value of ksp = 1.8 x 10-2 for the reaction pbcl2 (s) pb+2(aq) + 2cl -(aq). the concentration of the products. Natural gas has a geographical advantage over oil for suppliers in Pennsylvania. Our state sits on top of a large shale gas reserve that went into production in 2011. In fact, while the U.S. is still dependent on imports to meet all of its oil needs, we now have an abundance of gas and have become an exporter.. Main Difference - Syngas vs Water Gas. Syngas and water gas are two types of fuel gases. Syngas, also known as synthetic gas, is composed of hydrogen, carbon monoxide, and very often some carbon dioxide.Water gas consists mainly of carbon monoxide and hydrogen and is produced from syngas According to the world coal institute, there are still enough resources that we can relay up to 130, 42, and 60 more years for coal, oil, and natural gas, respectively. Key Differences. Biofuel is a fuel produced from the biomass, whereas fossil fuel is a fuel produced from the fossil remains of organisms
The difference between conventional and unconventional natural oil and gas simply refers to the types of rock within which the oil and gas are found, and the method by which they are extracted. In general terms, conventional oil and gas are found in relatively permeable materials in which the oil or gas can flow relatively freely towards a. Natural Gas. Natural gas can be found intermingled among the deposits of crude oil and shale oil. It can also be found in what is known as tight sand deposits, too. The primary difference between oil (either shale or crude) and natural gas is the degree to which either needs to be refined With mounting deaths from natural gas and oil rig explosions, it is good to review the deathprint, or the number of people killed per kWh produced, of our energy sources. It is greatest for coal. Depending on natural gas prices (per 1,000 cubic feet), propane could replace natural gas as a source of heating a building, home, or large volume structure. But, if natural gas prices are cheaper (e.g., under $20 per 1,000 cubic feet), the cost of using it to heat a home can be cheaper than propane, even with the efficiency difference Let's look at the differences between Coal and PetroleumCoalPetroleumCoal is found in solid statePetroleum is found in liquid stateCost of transportation of coal is high since it is hard and bulkyCost of transportation of petroleum is low because it is a liquidCoal emits smoke, ash and other harmfu