Модуль 3 - Passive Voice, особенности (1096807), страница 7

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Some of these pipes are two feet wide.Natural gas is sent in larger pipelines to power plants to make electricity or to factories because theyuse lots of gas. Bakeries use natural gas to heat ovens to bake bread, pies, pastries and cookies.Other businesses use natural gas for heating their buildings or heating water.From larger pipelines, the gas goes through smaller and smaller pipes to your neighborhood.In businesses and in your home, the natural gas must first pass through a meter, which measures theamount of fuel going into the building. A gas company worker reads the meter and the companywill charge you for the amount of natural gas you used.Energy can be found in a number of different forms.

It can be chemical energy, electrical energy,heat (thermal energy), light (radiant energy), mechanical energy, and nuclear energy.In some homes, natural gas is used for cooking, heating water and heating the house in a furnace.In rural areas, where there are no natural gas pipelines, propane (another form of gas that's oftenmade when oil is refined) or bottled gas is used instead of natural gas. Propane is also called LPG,or liquefied petroleum gas, is made up of methane and a mixture with other gases like butane.Propane turns to a liquid when it is placed under slight pressure. For regular natural gas to turn intoa liquid, it has to be made very, very cold.Cars and trucks can also use natural gas as a transportation fuel, but they must carry specialcylinder-like tanks to hold the fuel.When natural gas is burned to make heat or burned in a car's engine, it burns very cleanly. Whenyou combine natural gas with oxygen (the process of combustion), you produce carbon dioxide andwater vapor; plus the energy that's released in heat and light.Some impurities are contained in all natural gas.

These include sulphur and butane and otherchemicals. When burned, those impurities can create air pollution. The amount of pollution fromnatural gas is less than burning a more "complex" fuel like gasoline. Natural gas-powered cars aremore than 90 percent cleaner than a gasoline-powered car.That's why many people feel natural gas would be a good fuel for cars because it burns cleanly.Chapter 10: Biomass EnergyBiomass is matter usually thought of as garbage. Some of it is just stuff lying around -- dead trees,tree branches, yard clippings, left-over crops, wood chips (like in the picture to the right), and barkand sawdust from lumber mills. It can even include used tires and livestock manure.Your trash, paper products that can't be recycled into other paper products, and other householdwaste are normally sent to the dump. Your trash contains some types of biomass that can be reused.Recycling biomass for fuel and other uses cuts down on the need for "landfills" to hold garbage.This stuff nobody seems to want can be used to produce electricity, heat, compost material or fuels.Composting material is decayed plant or food products mixed together in a compost pile and spreadto help plants grow.California produces more than 60 million bone dry tons of biomass each year.

Of this total, fivemillion bone dry tons is now burned to make electricity. This is biomass from lumber mill wastes,urban wood waste, forest and agricultural residues and other feed stocks.If all of it was used, the 60 million tons of biomass in California could make close to 2,000megawatts of electricity for California's growing population and economy. That's enough energy tomake electricity for about two million homes!How biomass works is very simple. The waste wood, tree branches and other scraps are gatheredtogether in big trucks. The trucks bring the waste from factories and from farms to a biomass powerplant.

Here the biomass is dumped into huge hoppers. This is then fed into a furnace where it isburned. The heat is used to boil water in the boiler, and the energy in the steam is used to turnturbines and generators.Biomass can also be tapped right at the landfill with burning waster products. When garbagedecomposes, it gives off methane gas. You'll remember that natural gas is made up of methane.Pipelines are put into the landfills and the methane gas can be collected.

It is then used in powerplants to make electricity. This type of biomass is called landfill gas.A similar thing can be done at animal feed lots. In places where lots of animals are raised, theanimals - like cattle, cows and even chickens - produce manure. When manure decomposes, it alsogives off methane gas similar to garbage.

This gas can be burned right at the farm to make energy torun the farm.Using biomass can help reduce global warming compared to a fossil fuel-powered plant. Plants useand store carbon dioxide (CO2) when they grow. CO2 stored in the plant is released when the plantmaterial is burned or decays. By replanting the crops, the new plants can use the CO2 produced bythe burned plants.

So using biomass and replanting helps close the carbon dioxide cycle. However,if the crops are not replanted, then biomass can emit carbon dioxide that will contribute towardglobal warming.So, the use of biomass can be environmentally friendly because the biomass is reduced, recycledand then reused. It is also a renewable resource because plants to make biomass can be grown overand over.Today, new ways of using biomass are still being discovered.

One way is to produce ethanol, aliquid alcohol fuel. Ethanol can be used in special types of cars that are made for using alcohol fuelinstead of gasoline. The alcohol can also be combined with gasoline. This reduces our dependenceon oil – a non-renewable fossil fuel..

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