CH1 Environment Issue

8/10/2019 CH1 Environment Issue

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BTE 4216 BIOMASS ENERGY

CHAPTER 1

Energy Consumption,

Reserves, Depletion, andEnvironmental Issues



II. HISTORICAL ENERGY

CONSUMPTION PATTERNS

It was not too many years ago that humans' basic survival

depended in whole or in part on the availability of

biomass as a source of food stuffs for human and animal

consumption, of building materials, and of energy for

heating and cooking.

Biomass is now a minor source of energy and fuels in

industrialized countries. It has been replaced by coal,

petroleum crude oil, and natural gas, which have become

the raw materials of choice for the manufacture andproduction of a host of derived products and energy as

heat, steam, and electric power, as well as solid, liquid,

and gaseous fuels.







II. HISTORICAL ENERGY

CONSUMPTION PATTERNS

Between 1985 and 2005, annual energy consumption

increased 31 percent in the United States, while only 18

percent in Europe, and an overwhelming 250 percent in

China and India, although India’s total consumption is

small at only 3 percent of the world total.

In the United States, fossil fuels accounted for 86

percent of our total energy consumption in 2004.

Petroleum fuels, natural gas, and coal accounted for 40,

23, and 23 percent, respectively, with an additional 8percent from nuclear power and only 6 percent from

renewable sources, including hydroelectric (2.7 percent),

biomass/biofuels (2.7 percent), and 0.6 percent from

solar, wind, and geothermal energy sources combined.



WORLD ENERGY CONSUMPTION, 1970-2025, EIA





WORLD ENERGY CONSUMPTION I S PROJECTED TO R ISE BY 59

PERCENT BETWEEN 1999 AND 2020, REACHING 607

QUADRILLION BRIT ISH THERMAL UNITS (BTUS) .



DEVELOPING A SIA AND C ENTRAL AND SOUTH AMERICA ARE EXPECTED TO

HAVE THE MOST RAPID GROWTH RATES IN ENERGY DEMAND OVER THE

NEXT TWO DECADES. IN BOTH REGIONS, TOTAL ENERGY DEMAND IS

EXPECTED TO GROW BY ABOUT 4 PERCENT PER YEAR BETWEEN 1999

AND 2020 .







Oil is expected to remain the dominant energy fuel as it has been for decades.

In the industrialized world, increases in oil use are projected primarily in the

transportation sector, where there are currently no available fuels to compete

with oil products

Natural gas is projected to be the fastest growing primary energy source

worldwide, maintaining growth of 3.2 percent annually over the 1999-2020

period, more than twice as high as the rate for coal. Natural gas consumption

is projected to rise from 84 trillion cubic feet in 1999 to 162 trillion cubic feet

in 2020, primarily for electricity generation. Gas is increasingly seen as the

desired alternative for electric power, given the efficiency of combined-cyclegas turbines relative to coal- or oil-fired generation, and because it burns more

cleanly than either coal or oil, making it a more attractive choice for countries

interested in reducing greenhouse gas emissions.

Coal use worldwide is projected to increase by 1.7 billion short tons (36

percent) between 1999 and 2020. Substantial declines in coal use are

projected for Western Europe and the EE/FSU countries where natural gas is

increasingly being used to replace coal, to fuel new growth in electric power

generation, and for other industrial and building sector uses . In the

developing world, however, even larger increases in coal use are expected. The

largest increases are projected for China and India, where coal supplies are

plentiful. Together these two countries account for more than 90 percent of

the projected rise in coal use in the developing world over


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III. FOSSIL FUEL RESERVES AND

DEPLETION

The motivation for development and use of alternative

fuels include:

(1) diminishing reserves of readily recoverable oil

(2) concern over global climate change

(3) increasing fuel prices

(4) the desire for energy independence and security.



Global depletion of petroleum reserves at annual consumption

growth rate of 1.2%.















III. FOSSIL FUEL RESERVES AND

DEPLETION

Currently available fossil fuel sources are estimated tobecome nearly depleted within the next century,with petroleum fuel reserves depleted within 40years.

The United States imports 10 million barrels of oil perday of the existing world reserves (1.3 trillion barrels)

Crude oil prices have risen from less than $20/barrelin the 1990s to nearly $100/barrel in 2007

Accounting for military aid and subsidies to protectand maintain an uninterrupted flow of crude oil fromunstable regions of the world, the true cost of oil hasbeen estimated as greater than $100/barrel since

2004.





Examination of the world's proved reserves of coal, crude oil,and natural gas and their regional locations shows that wellover half of the world's crude oil and natural gas supplies arelocated in the Middle East and the former Soviet Union, whileNorth America, the Far East, and the former Soviet Union haveover 70% of the coal reserves.

Oil has intrinsic properties such as high energy density, ease oftransport, storage, and conversion to storable liquid fuels, andan existing infrastructure that facilitates worldwide distributionof refined products to the consumer, it is the fossil fuel of choicefor the manufacture of motor fuels.

Some countries, such as Japan, that have little or no provedreserves of oil consume relatively large quantities and aretherefore strongly dependent on imports to meet demand.Some countries, such as Saudi Arabia, have an abundance ofproved oil reserves and supply their own demands as well as alarge fraction of the world's markets.



Natural gas is somewhat similar to oil in that it is a relativelyclean-burning fuel compared to coal. Long-distance pipelineshave been built in many developed and developing countriesto deliver gas from the producing areas to large urbanmarkets where it is delivered to the consumer via local gas

distribution networks.

Japan is an example of a country that has no natural gasreserves, yet consumes considerable natural gas that istransported to Japan from producing countries as liquefiednatural gas (LNG) in large cryogenic tankers.

Another example is the utilization of the large reserves ofnatural gas in Eastern Europe. High-pressure pipelines areused to transport natural gas from producing regions inEastern Europe to Western Europe where natural gas reservesare small.



GAS PIPELINE



IV. ENVIRONMENTAL ISSUES

ENVIRONMENTAL IMPACT

(1) Biofuel production from biomass is largely carbon

neutral—that is, the CO2 produced as the fuel is

combusted, is offset by the carbon absorbed as the

biomass is grown.

(2) Bioconversion processes in general do not produce

hazardous compounds, and if toxic solvents and

chemicals are avoided in the processing stages, then

fewer environmental pollutants are produced.

(3) Biomass production and microbial conversion

processes can be developed and used in a more

distributed manner (locally), avoiding the need for

transport of fuels via cargo ships or pipelines for long

distances.



IV. ENVIRONMENTAL ISSUES

THE GREENHOUSE EFFECT

Gradually increasing tropospheric concentrations of carbon dioxide(CO2), methane (CH4), and nitrous oxide (NOx) are believed to trapan excessive amount of solar radiation reflected from the earth. Thetrapped radiation is predicted to cause significant ambienttemperature increases (global warming).

Other issues include ozone formation over populated areas due tophotochemical interactions of hydrocarbon, carbon monoxide (CO),and nitrogen oxide (NOx) emissions, primarily from motor vehicles;

Natural ozone layer destruction in the stratosphere byphotochemical reactions of organic chlorofluorocarbon compounds

(CFCs) resulting in increased penetration to the earth's surface ofshorter-wavelength ultraviolet light that can cause skin cancers;

Acid rain, which has harmful effects on buildings;

The growth of biomass and is caused by sulfur oxide (SOx)

emissions from the combustion of sulfur-containing fossil fuels.







Heat produced by

burning

pulverized coal in

a furnace boils

water to produce

steam that spins a

turbine to

produce

electricity.

The steam is

cooled,

condensed, and

returned to theboiler for reuse.

Waste heat can be

transferred to the

atmosphere or to

a nearby source

of water.

The largest coal-

burning power

plant in the

United States,

located in Indiana,

burns three 100-

car trainloads ofcoal per day

Coal-burning power plant.





Developing countries alone account for 81 percent of theprojected increment in world carbon emissions between1990 and 2010 and 76 percent between 1990 and 2020.

Oil consumption is projected to account for the largestincrement in worldwide carbon dioxide emissions. In2020, emissions related to oil use are projected to be 1.9billion metric tons carbon equivalent higher than the1990 level. Emissions from natural gas use are expected

to be 1.4 billion metric tons above 1990 levels in 2020and emissions from coal use 0.7 billion metric tons above1990 levels. Although natural gas use is expected toincrease at a faster rate than oil use, it is a less carbon-intensive fuel.





GLOBAL WARMING POTENTIALS





REFERENCE

1. Dr Donald L. Klass (1998). Biomass Renewable

Energy, Fuels and Chemicals.

2. Drapcho, Nhuan and Walker (2008). Biofuels

Engineering Process Technology.

Documents

CH1 Environment Issue