Geothermal&Hydrogen Energy

8/4/2019 Geothermal&Hydrogen Energy

1/19

2011

Salma Ikbarieh

05/10/11

[Hydrogen and Geothermal

Energy]


2/19

Page 2

Table of Contents

Introduction ......................................................................................................................... 3

Geothermal Energy ............................................................................................................. 4

Geothermal resources...................................................................................................... 5

Hydrothermal (natural steam reservoirs) .................................................................... 5

Geopressured reservoirs .............................................................................................. 6

Geothermal gradients .................................................................................................. 6

Molten magma ............................................................................................................ 7

Environmental impact ..................................................................................................... 7

Depletion of resources ................................................................................................ 7

Damage to natural geothermal features ...................................................................... 7

Subsidence .................................................................................................................. 7

Polluting waterways .................................................................................................... 8

Air emissions .............................................................................................................. 8

Advantages and Disadvantages ....................................................................................... 8

Advantages:................................................................................................................. 8

Disadvantages (challenges): ........................................................................................ 9

Uses ............................................................................................................................... 10

Hydrogen Energy .............................................................................................................. 12

Resources and Uses....................................................................................................... 12

Hydrogen Fuel Cells ..................................................................................................... 13

Advantages and Disadvantages ..................................................................................... 14

Advantages ................................................................................................................ 14

Disadvantages ........................................................................................................... 14

Environmental Impacts of Hydrogen power ................................................................. 15

Applications .................................................................................................................. 16

Hydrogen Power- UAE ................................................................................................. 16

Conclusion ........................................................................................................................ 17

Works Cited ...................................................................................................................... 18

Table of Figures ................................................................................................................ 19


3/19

Page 3

Introduction

Our population and technology development are increasing, and as long as they

both increase our demand on energy increases. This vast demand that is increasing

rapidly caused a lot of problem to our universe. Steps towards better technology are

faced by steps backwards because of the global warming. Do we need to make

choice or there is a way out? The answer is no. Then what is the solution for that?

Will scientists and researchers gathered there effort trying to find a solution. Part of

the solution was in finding an alternative methods and sources to generate energy.

Two of those sources are the geothermal energy and the hydrogen energy. This

report is going to discuss each one in depth.


4/19

Page 4

Geothermal Energy

Geothermal energy is defined as heat from the Earth (GEA), and the term geothermal

came from a combination of two Greek words: geo, meaning earth and thermal,

meaning heat (Gevorkian, 2010). Geothermal energy is force that: (1) moves

continents, (2) builds mountains, and (3) produce volcanic eruptions. (Nemzer).

At the earth core about 4000 miles deep temperatures might reach more than 5000o C this

tremendous heat flows outward melting huge mass of rocks, the molten rock is called

magma which moves through the cracks carrying the heat. Sometimes this heat appears

above the earth surface as lava. However most of the earth heat remains below the curst

heating up the rocks and the trapped water in the permeable and porous rocks under a

layer of impermeable rock, forming a geothermal reservoir. Moreover sometimes this

trapped water might manifest itself on the surface as geysers, hot springs, etc (GEA;

Gevorkian, 2010; Nemzer)

Figure 1 : Earth core (life in universe)

Electricity from geothermal energy had a modest start in 1904 at Larderello, Italy, with

an experimental 10 kW-generator. Nowadays, it has grown to 8771 MW in 25 countries

producing an estimated 54793 GWh annually. This electricity production serves about


5/19

Page 5

1.0% of our planets population. The development of worldwide geothermal power

production can be seen in Figure 2. The sharp drop in the production was caused by the

destruction of the Italian field at the end of World War II. Since WWII, geothermal

power has grown at a rate of 7.0% /yr (Lund, 2008 ) .

Figure 2 : Geothermal power grow rate (Lund, 2008 )

We can generate geothermal energy by drilling deep holes into the earths crust pumping

cold water through one end and then by the time it rises back to the surface the water can

be hundreds of degrees Celsius which we then use as steam to drive a turbine whichdrives a generator creating power. Geothermal energy is one of the best natural energies

available. (Advantages Of Geothermal Energy)

Geothermal resources

Hydrothermal (natural steam reservoirs)

Hydrothermal reservoirs consist of a heat source covered by a permeable formation

through which water circulates. Steam is produced when hot water boils underground and

some of the steam escapes to the surface under pressure. At the surface, once the

impurities and tiny rock particles are removed, the steam is piped directly to the electrical

generating station. These systems are the simplest and cheapest form of geothermal


6/19

Page 6

energy. The Geysers, ninety miles north of San Francisco, California, are the most

famous example of this type. The Geysers Geothermal fields are the world's largest

source of geothermal power, according to the Energy Information Administration.

Under some rare geological conditions the pressures in hydrothermal reservoirs are so

low that the water has boiled to steam, as at The Geysers power development. While this

reservoir form is the rarest, it is the easiest and most economical to tap, largely because

there is little corrosion problem and little needs to deal with the large amounts of brine

that must be drawn from and reinjected into a hot water reservoir. It is a very inexpensive

source of electricity, yet its rarity is not likely ever to contribute more than a few

gigawatts of generating capacity to this country.

Geopressured reservoirs

They are deep reservoirs of high pressured hot water which contain a dissolved natural

gas. To have a geopressured reservoir that is economically able to produce energy the

following features have to be included:

(1)A hot geothermal fluid, more than 230oC.(2)Significant methane dissolved in the geothermal fluid, if it contains a natural gas

only the reservoir might be uneconomical.

(3)Significantly thick, permeable, and faulty-bounded high-pressured sand.(4)The energy can be produces without subsidence. (DiPippo, 2008; GEOFAR,

2009)

Geothermal gradients

The internal temperature of the earth increase we go down. An average geothermal

gradient on the surface of the earth is about 25oC, but sometimes the temperature is

higher because of some natural factors as active tectonic forces. However, generally the

geothermal gradient increases 30oC every 1 km depth. Thats why if we drilled shafts

with 6 km deep in hot, dry rocks we will be able to produce a potential commercial

energy. (CliffsNotes; Gevorkian, 2010)


7/19

Page 7

Molten magma

This geothermal resource goes directly to the source. The idea is to drill a well into

magma body that is relatively close to the surface of the earth. Then insert an injection

pipe and pump cold water down the well under high pressure. Now the magma supposes

to solidify on a form of glassy material that will eventually crack under the huge thermal

stress that its imposed to. If there is away for the water to return and manifest on the

earth surface then this hot water will be ready to generate energy. Although it seems

simple to explain, using the molten magma as a source of geothermal energy is still a

topic that is under study especially if we are talking about from the economical

investment perspective (DiPippo, 2008).

Environmental impact

Depletion of resources

The extraction of the geothermal fluids, eventually remove the heat from the natural

reservoirs. However we could overcome this imbalance by making the geothermal fluid

run on a closed loop (Stewart, 2009).

Damage to natural geothermal features

Wherever there is geothermal development damage or deterioration on the geothermal

features, such as hot springs and geysers, can easily happen, causing ground sage in some

places, and decline of these geothermal features as the supply of steaming water from

below was depleted (Stewart, 2009).

Subsidence

The Extraction of geothermal fluids can decrease the pressure in underground reservoirs

causing land sinking. This may also put a strain on bores and pipelines, causing damage

in the buildings, roads, and surface patterns. The largest subsidence on record is at

Wairkei; in 2005 the centre of the subsidence bowl sank 14 meters lower than it was

before geothermal power plant was built (Stewart, 2009).


8/19

Page 8

Polluting waterways

Geothermal fluids may contain hazardous gases or materials because of the underground

contact between hot fluids and rocks. If waste is released into rivers or lakes damage in

the aquatic life and water will occur making these waterways unsafe for drinking or

irrigation. However we can overcome this problem by injecting the geothermal fluids

back to the geothermal system (Stewart, 2009).

Air emissions

Emissions of greenhouse gases, like CO2 and H2S, could be correlated with the extraction

of geothermal fluids. If these gases reach a certain level, they will jeopardize the health

and the life of people working in the geothermal fields, they can also be a problem in

urban areas. Though, geothermal power plants release far fewer greenhouse gases than

fossil fuels power plants. Moreover; Binary, air-cooled power plants have effectively

zero emissions (Stewart, 2009; GEA).

Advantages and Disadvantages

Advantages:

Little land usageAccording to the U.S. Department of energy geothermal energy use less land space than

fossil fuel and renewable energy sources. Moreover if we compare the land space needed

to produce 1 GWh a coal facility will need an area of 3632m2 while a geothermal facility

will need an area of 404 m2

only. (GEA)


9/19

Page 9

Figure 3 : Land use comparison (GEA)

Renewable, Continues reliable energy

This is because the earth heat is a constant source, and the rainwater and snowmelt will

essentially continue feeding the underground thermal aquifers. Furthermore, the

geothermal energy doesnt need geological times for regeneration as fossil fuel reserves

do. (GEA; Gevorkian, 2010)

Benefits local economics

There are many economical benefits from using the geothermal energy such as:

(1)Reducing the healthcare related costs, since the use of geothermal energy willcounterbalance the emissions of NO2 and SO4 from the fossil fuel power plants.

(2)Providing a stable source of employment.(3)Reducing the local energy imports.(4)Producing a cost-competitive power. (GEA)

Low production cost

The power plant generates the energy that it needs to start production by itself. So that, no

fuel will be needed to run the production. Hence costs of purchasing, transporting, and

cleaning up the fuel will be eliminated. (GLA; Advantages Of Geothermal Energy)

Disadvantages (challenges):

Cost of plant insulation

The installation of geothermal plant requires significant expenses such as:

0

500

1000

15002000

2500

3000

3500

4000

coal* Solar

Thermal

wind** geothermal

m2/G

wh

30 YEAR LAND USE COMPARSION


10/19

Page 10

(1)Geological and environmental study cost.(2)Heavy and expensive mechanical components costs (example: circulating pumps,

heat exchangers).

(3)Maintenance expenses. (GEA)Engineering and environmental challenges

The geothermal energy technologies insulation, specially the deep penetration-type,

needs significant engineering design and a through environmental study. (Gevorkian,

2010)Hazardous gases

An important disadvantage of geothermal energy is the chances of hazardous gases like

H2S or hazardous materials like NH3 to be released causing environmental pollution,

which is not easy to get rid of. (Kanade) Lifespan and location

The biggest disadvantage of geothermal energy is the big uncertainty over the lifespan of

the project. This uncertainty is because the locations of the easy access to the geothermal

recourses are usually located in areas of volcanoes, and earthquakes. Such location will

eventual jeopardize any geothermal power plants that could be built there, making the

investment on such energy undesirable for investors. (Kanade)

Uses

Geothermal electricity

Geothermal energy generally produces electricity by drilling the wells into a geothermal

reservoir. These wells will carry the geothermal fluid to the earth surface and passing it to

an electrical generator. This conversion process is done at geothermal power plants

(GEA). There are four types of geothermal power plans, which are:- Flashed Steam Plants- Dry Steam Plants- Binary Power Plants- Hybrid Power Plants. (Evans, 2007)


11/19

Page 11

Heat uses

Back in the history, geothermal water was used by the Romans for eye and skin treatment

and buildings heating. In addition the medieval wares included fight over lands with hot

springs. Furthermore, for hundreds of years Tuscany, Italy, used natural steam to produce

vegetables in the winter. Geothermal heat is really amassing its free and it can be used

directly in many applications such as:- Air conditioning (heating and cooling)- Food preparation- Balneology (ex. Spas)- Agriculture and greenhouses- Aquaculture- Industrial processes. (Lund, 2008 )


12/19

Page 12

Hydrogen Energy

Hydrogen is a colorless gas that is the most available gas in the universe. The hydrogen

atom is made from one atom and one electron only, which makes H2a very light gas. Its

even lighter than the air. However the hydrogen contains an energy that is three times

larger than the energy of the gasoline. (U.S. EIA)

Resources and Uses

Hydrogen is an energy carrier just like the electricity, and just like the electricity

hydrogen can be produced from variety of sources that can be renewable like: solarthermal and biomass, or non-renewable sources like: natural gas and coal. At the same

time hydrogen can be used in transportation, industrial applications, buildings, and the

list can get longer (European Commission, 2003).

There are several ways in which we can produce hydrogen. Two common procedures are

electrolyses and steam reforming. In the electrolyses procedure the water is separated into

oxygen and hydrogen. The procedure is considered to be an expensive procedure, yet its

the best because there are no emissions produced by this procedure. On the other hand

there is the steam reforming procedure which is the least expensive but produces

greenhouse gases. This is because the steam reforming procedure is done by separating

the hydrogen from the methane, CH4 (European Commission, 2003) .


13/19

Page 13

Figure 4 : Hydrogen: primary energy sources, energy converters and applications (European Commission,

2003).

Hydrogen Fuel Cells

Hydrogen fuel cells are devices that convert the hydrogen into electricity, water and heat.

Fuel cells operate like the casual batteries, yet it doesnt need electrical recharge. The

question now is: How do these fuel cells work? Will a typical fuel cell is like a sandwich

of five layers. The electrolyte is the middle layer sandwiched between two electrodes

which are sandwiched between two bipolar plates. The hydrogen enters from bipolar

plate that is near the anode. This hydrogen goes through the channels to the anode to be

separated by the catalyst membrane into electrons stream that take an external path as

electricity, and protons that go through until it reach the cathode where it meet back the

electrons. Then the electrons, the protons and the oxygen coming out of the air collide

together forming heat and water as an output of the fuel cell (European Commission,

2003; CHFCA).


14/19

Page 14

Figure 5 : Hydrogen fuel cell illustration (European Commission, 2003)

Advantages and Disadvantages

Advantages

There are several advantages of hydrogen power. First of all, if we produced the

hydrogen power from a renewable energy source, then we will be able to get a clean

power source. Second, since we are able to produce the hydrogen power from vast variety

of resources, and then hydrogen power can be produced in any country. Third, the

hydrogen power can be produced on site, meaning that it doesnt need to be generated on

somewhere and then to be transferred to somewhere else. An obvious example of that are

the fuel cells. Forth, the hydrogen is safer than gasoline, diesel, and natural gas; yet it can

compete them effectively on the economical side. Last but not the least; hydrogen can

help in maintaining the fossil fuel reserves (AFVTech).

Disadvantages

On the other side of the equation there are some disadvantages of hydrogen power. The

first one is the difficulty in storing and distributing hydrogen. Another one is that

extracting hydrogen might necessitate the bourn of fusel fuels which eventually will emit

greenhouse gases. Moreover the hydrogen power is considered to be the most expensive

power source. Statistics of the U.S. Department of energy show that the cost of hydrogen


15/19

Page 15

fuel cell manufacturing in 2002 reached $275/kW and dropped to $51/kW in 2010. This

shows that we are able to overcome the high expense of hydrogen power generation by

the technology development (Hydrogen power; U.S.DOE).

Figure 6 : Cost reduction in hydrogen fuel cell manufacturing (U.S.DOE)

Also there are some disadvantages related to the hydrogen fuel cells. One of them is its

size. The hydrogen fuel cell is big and bulky. Its three times larger than the casual gas

tank. Furthermore, there is a big safety issue related to the hydrogen fuel cell, which is

the probability of it to explode. This explosion might happen because of the ability of the

hydrogen liquid to freeze which eventually will plug up the valve causing a high pressure

and the only release for this pressure is the explosion (Agarwal).

Environmental Impacts of Hydrogen power

Since the hydrogen power generation tends to be from a fossil fuel source, our hydrogen

power generation is contributing in emitting greenhouse gases like CO2 which contribute

in the global warming. Furthermore the hydrogen system if was not designed probably

can release the hydrogen in side it very fast. This released hydrogen can help in

increasing the reaction rate of methane and ozone, making the global warming issue

enlarges ( European Commission DG Environment News Alert Service, 2006).


16/19

Page 16

Applications

NASA is considered to be the largest hydrogen power consumer. NASA uses the

hydrogen power in several applications like a fuel to lift the space shuttles, and a source

of drinking water for the space shuttle crew. Hydrogen powered vehicles is another

application, where the hydrogen is used to generate electricity that is going to run the

vehicle motor (U.S. EIA).

Hydrogen Power- UAE

With initial cost of 7 billion dirham Emirati, Masdar and British Petroleum signed acontract to build hydrogen manufacturing power plant that is going to cover 5% of Abu

Dhabi power generation capacity. The project is going to provide from 3000 to 4000

construction jobs during the construction phase and about 100 permanent jobs when the

power plant starts operating. The hydrogen generation will be produced by burning the

natural gas. The generated CO2 which estimated to reach 1.7 million tons is going to be

injected back into the oil field to help in maintain the pressure of the oil field. This

project is going to increase the oil reserved of Abu Dhabi and its expected to finish in

2014, however some recent news says that the project will be delayed (Hydrogen Power

Abu Dhabi (HPAD)).


17/19

Page 17

Conclusion

The geothermal energy is a very good power source that needs an excessive research

and technological development to be able to gather its benefits safely. On the other

hand the hydrogen power is a potential power source that would be very efficient ifwe are able to generate it from renewable and clean resources. At the end we can see

that we need a development in the renewable and alternative energy filed that

equals the vast, rapid change in the development of the technology to be able to

adopt those technological development without jeopardizing our environmental

balance.


18/19

Page 18

Works Cited

(n.d.). Retrieved from life in universe: www.lifeinuniverse.org

European Commission DG Environment News Alert Service. (2006, October 19).

Environmental Impacts of Hydrogen-based Energy Systems. Science for Environment

policy , p. 1.

Advantages Of Geothermal Energy. (n.d.). Retrieved April 22, 2011, from

http://www.clean-energy-ideas.com

AFVTech. (n.d.).Advantages of Hydrogen. Retrieved May 10, 2011, from Alternative

Fuel Vehicle Technology : http://www.afvtech.com/

Agarwal, A. (n.d.). 3 Great Disadvantages Of Hydrogen Fuel Cells. Retrieved April 25,

2011, from EzineArticles: http://ezinearticles.com

CHFCA. (n.d.). Canadian Hydrogen and Fuel Cell Association. Retrieved May 10, 2011,

from http://www.chfca.ca

CliffsNotes. (n.d.). Geothermal Gradients. Retrieved April 23, 2011, from

http://www.cliffsnotes.comDiPippo, R. (2008). Geothermal Power Plants. Butterworth-Heinemann.

European Commission. (2003). RTD info.Hydrogen Energy and Fuel Cells - A vision of

our future , pp. 10 - 11.

Evans, S. (2007, October 22). The Uses of Geothermal Energy. Retrieved May 10, 2011,

from Green Living Ideas: http://greenlivingideas.com

GEA. (n.d.). Geothermal Energy Association. Retrieved April 16, 2011, from http://geo-

energy.org

GEOFAR. (2009, October 12). GEOPRESSURIZED SYSTEM. Retrieved April 23, 2011,

from energia: http://www.energia.gr/geofar/articlefiles/geothermalinnovative-

geopressurized.pdf

Gevorkian, P. (2010).Alternative Energy Systems in Bulding Design. McGraw-Hill.

GLA. (n.d.).Advantages and Disadvantages of Geothermal Energy. Retrieved April 22,

2011, from http://www.greenlivinganswers.com

Hydrogen power. (n.d.). Retrieved May 10, 2011, from Energy: http://www.odec.ca/

Hydrogen Power Abu Dhabi (HPAD). (n.d.). Retrieved April 25, 2011, from Hydrogen

Power Abu Dhabi: http://www.hydrogenenergy.com

Kanade, S. (n.d.). Geothermal Energy Disadvantages. Retrieved April 22, 2011, from

www.buzzle.com

Lund, J. W. (2008 , January 1). 100 Years of Geothermal Power Production. Geo-HeatCenter Quarterly Bulletin , pp. 12-19.

Nemzer, M. (Director). What is geothermal energy? [Motion Picture]. Tiburo.

Stewart, C. (2009, March 2). Geothermal energy - Effects on the environment. Retrieved

April 22, 2011, from http://www.teara.govt.nz

U.S. EIA. (n.d.).Energy Kids. Retrieved May 8, 2011, from http://www.eia.doe.gov/


19/19

U.S.DOE. (n.d.).Accomplishments and Progress. Retrieved April 27, 2011, from U.S.

Department of Energy: http://www1.eere.energy.gov

Table of Figures

FIGURE 1:EARTH CORE (LIFE IN UNIVERSE) ........................................................................ 4

FIGURE 2:GEOTHERMAL POWER GROW RATE (LUND,2008) .............................................. 5

FIGURE 3:LAND USE COMPARISON (GEA) .......................................................................... 9

FIGURE 4:HYDROGEN: PRIMARY ENERGY SOURCES, ENERGY CONVERTERS AND

APPLICATIONS (EUROPEAN COMMISSION,2003). ....................................................... 13

FIGURE 5:HYDROGEN FUEL CELL ILLUSTRATION (EUROPEAN COMMISSION,2003) ......... 14FIGURE 6:COST REDUCTION IN HYDROGEN FUEL CELL MANUFACTURING (U.S.DOE) ...... 15

Geothermal&Hydrogen Energy

Documents

Transcript of Geothermal&Hydrogen Energy