major energy resources non renewable resources fossil fuels – coal, petroleum, natural gas,...
TRANSCRIPT
• Major Energy Resources • Non Renewable Resources Fossil Fuels – Coal,
Petroleum, Natural gas, Biofuels, Biogas, wood• Renewable Resource• Nuclear• Solar• Hydropower• Wind Power• Tidal and Ocean Thermal
• Geothermal
Observations of Climate Change – Global Warming
Temperature, Evaporation & rainfall are increasing; More of the rainfall is occurring in downpours Corals are bleaching Glaciers are retreating Sea ice is shrinking Sea level is rising Wildfires are increasing Hurricane, storm and flood damages are much larger
Nuclear PowerFission of 1 kilogram of uranium releases more energy than does burning 3 million kg of
coal.
Geothermal Features associated with groundwater
• Hot springs• Water is 6-9oC warmer than the
mean annual air temperature of the locality
• The water for most hot springs is heated by cooling of igneous rock
Features associated with groundwater
• Geysers• Intermittent hot springs
• Water erupts with great force
• Occur where extensive underground chambers exist within hot igneous rock
• Groundwater heats, expands, changes to steam, and erupts
Evolution of ageyser eruption
Yellowstone Geyser erupting – geothermal energy for a ‘Supervolcano’
Geothermal Energy is energy stored in the form of heat beneath the surface of the solid earthGeothermal Energy can be spectacular!
Geysers and volcanoes show the earth’s heatPhotos of US Geological Survey
What is geothermal energy? Geothermal energy is heat from Earth’s interior. Geothermal heat originates from Earth's fiery formation more than four billion years ago. At Earth's core— 7900 km (4,000) miles deep - temperatures may reach over 6000 degrees Centigrade, 9,000 degrees Fahrenheit
•Direct Sources function by sending water down a well to be heated by the Earth’s warmth.
•Then a heat pump is used to take the heat from the underground water to the substance that heats the house.
• Then after the water it is cooled is injected back into the Earth.
•Ground Heat Collectors This system uses horizontal loops filled with circulating water at a depth of 80 to 160 cm underground.
Borehole Heat Exchange
This type uses one or two underground vertical loops that extend 150 meters below the surface
Graph from Geothermal Education Office, California
Hawaii
Pacific Ocean
‘Ring of Fire’
High-Enthalpy Geothermal Energy world-wide
Sources of Earth’s Internal Energy
•About 70% comes from the decay of radioactive nuclei with long half lives that are embedded within the rocks in lithosphere and mantle
•Some energy is from residual heat left over from Earth’s formation.
Lithosphere
Temperature increases with depth in
Graph from Geothermal Education Office, California
Inner Core
Outer Core
Mantle
Lithosphere
Geothermal Energy is energy stored in the form of heat beneath the surface of the solid earth. Geothermal gradient
Normally 20 to 30º C / km, 1300-1400º C at base of lithosphere, 3000-6000º C + in core
Geothermal Power: Natural steam is extracted from wells to power the turbine generator. The left-over cool water is pumped down to sustain production.
Hawaii Geothermal AreaThe Hawaii geothermal area includes the Puna Geothermal Venture, which is located about 38 km (21 miles) south of Hilo on the Big Island of Hawaii. The facility is situated along the Lower East Rift Zone of the Kilauea Volcano. At the Puna Geothermal Venture, geothermal fluid is brought to the surface through production wells, which tap into the resource at a depth of almost a mile. The steam, along with its non-condensable gases, is routed to the power plant and used to produce electricity for the Big Island of Hawaii.
Benefits of Volcanoes: Geothermal Energy - One of the benefits of volcanism is geothermal power. The geothermal power plant on Kilauea's east rift zone is shown here. Pu'u O'o is up-rift from this plant. (This photo was taken on December 29, 1989.) The drilling has encountered some of the hottest underground fluids yet found. At a depth of 1,969 m the hole has a temperature of 350 degrees C. Increased development of Hawaii's geothermal resources is under consideration
Hawaii Geothermal Inter-island Submarine Cable Project Proposed Route (Fesmire and Richardson, 1990).
Map of the major islands of Hawaii showing the location of the 20 Potential Geothermal Resource Areas (PGRAs)
HAWAII AND GEOTHERMALWHAT HAS BEEN HAPPENING?There is still resistance to using geothermal energyby some members of he local population even though theabove issues have been and will continue to be addressed bythe government and the developers. However there are wellorganized groups and various community organizations thatwill continue to express concern in various ways about theability of the government and developers to provide sociallyand environmentally sound geothermal power. Further, thelevel of support given by the state’s political establishment toexpansion of geothermal capacity–
Puna Geothermal Venture geothermal power plant provides about 20% of electricity demand on the Big Island of Hawaii.
The 30 megawatt (MW) PGV plant uses air-cooled condensers and noise reduction enclosures. It’s a low-profile plant, 8 meter, 24 feet high, and has near zero emissions. Geothermal fluid and gas is reinjected into the deep earth.
Global Warming and the Fossil Fuels:There are approximately 1700 kWh of electricity in a barrel of fuel oil, however, power plants are, on average, 31% efficient and an additional 5% of that energy is lost in transmissionfrom source to user. Thus, 1700*0.31*0.95 = 501 net kWh per barrel.Burning of a barrel of crude oil 0.43 tons of carbon dioxide are released into the environment. A barrel has 42 gallons, one gallon produces 0.011 tons.
Steam Engine
Internal Combustion Engine
Piston
Steam Engine
Effect on Coastal AreasLava from Kupaianaha pond enters the ocean near Kalapana and extends the coastline (December 27, 1989). Intermittent littoral (sea shore) explosions added spatter to a large littoral cone on top of the sea cliff. Lava flows temporarily destroy land. However, when these same flows reach the sea, new land is added to the total area of the island.
Different Geothermal Energy Sources
Hot Water Reservoirs: As the name implies these are reservoirs of hot underground water. There is a large amount of them in the US, but they are more suited for space heating than for electricity production.
Natural Steam Reservoirs: In this case a hole dug into the ground can cause steam to come to the surface. This type of resource is rare in the US.
Geopressured Reservoirs: In this type of reserve, brine completely saturated with natural gas in stored under pressure from the weight of overlying rock. This type of resource can be used for both heat and for natural gas.
Normal Geothermal Gradient: At any place on the planet, there is a normal temperature gradient of +300C per km dug into the earth. Therefore, if one digs 20,000 feet the temperature will be about 1900C above the surface temperature. This difference will be enough to produce electricity. However, no useful and economical technology has been developed to extracted this large source of energy.
Hot Dry Rock: This type of condition exists in 5% of the US. It is similar to Normal Geothermal Gradient, but the gradient is 400C/km dug underground.
Molten Magma: No technology exists to tap into the heat reserves stored in magma. The best sources for this in the US are in Alaska and Hawaii.
World Geothermal Provinces
Indian Plate
Geothermal Energy Electricity Power Generation
Alternate Geothermal Technology – Power Tube
A short glimpse at geothermal power
Photo courtesy of ENEL/ERGA, Italy
First experiment to produce geo-thermal power, done in Italy in 1904 by prince Ginori Conti
Modern geothermal power plants in Larderello, Italy
Photos: Lund
A short glimpse at geothermal power
Principle of EGS system for geothermal power production
Drilling rig at the European R&D site Soultz-sous-Forêts (F)
Deep Geothermal Energy
doublet system, used since the late 1970s in France and since 1984 in (Eastern) Germany
Geothermal heating plant Neustadt-Glewe photo O. Joswig
• Present world-wide geothermal energy resources are constrained to areas where hot springs, geysers, and volcanic activity produce sufficient heat energy near the Earth’s surface for electric power generation. These areas follow plate tectonic boundaries around the world. Vast areas of the Earth lie sufficiently far from these boundaries that they are generally untapped for geothermal electric power production.
• A clean, renewable and environmentally benign energy source based on the heat in the earth
• Used in 58 countries of the world. Known in over 80 • Electricity generation 53 TWh/a in 22 countries• Direct heating use 53 TWh/a in 55 countries• Geothermal is number three of the renewable energy sources in world electrictity
production after hydro and biomass. It is followed by wind and solar energy
Kenya 58
Mexico 858Guatemala 33El Salvador 161Nicaragua 70Costa Rica 143
China 29
Russia 23
Philippines1931
Indonesia 787
Turkey 20
New Zealand 437
Thailand 0.3
USA 2002
Ethiopia 9
Italy 762
Iceland 200
Azores 16Japan 549
Australia 0.2
Guadeloupe 4
Geothermal electricity Geothermal electricity Installed capacity MWe 2001Installed capacity MWe 2001
U.S. Geothermal Provinces
United States Geothermal Electric Power Generation Potential(GeoPowering The West - DOE, 2000)
Top 3 States: Nevada, California, UtahOther High Potential States: Idaho, Hawaii, New Mexico, Oregon, South Dakota, Texas, and Wyoming
The basic requirements for an exploitableDPSGE geothermal region are similar tothose for oil and gas exploration:
1) a sufficiently high geothermal gradient;
2) A significantly large, porous and permeable reservoir to receive and heat injection fluids;
3) A seal to contain the system.
Water temperature (optimum range)
230o to 380o F (110o to 193o C)
Construction costs ~ $1500 per kW
including exploration and drilling.
10 Mw plant $15,000,000
(National Renewable Energy Laboratory, 1999)
Geothermal Delivery SystemsExisting Plant DesignsDry Steam Power Plants – use steam directly.Flash Steam Power Plants – hot water under pressure (most common).Binary Cycle Power Plants – hot water through heat exchanger.Feedstock Systems – incremental heat in elevated water temperatures.
New Plant DesignsPower Tube – iso-pentane & iso-butane into subsurface.
Direct uses of geothermal energy is appropriate for sources below 1500C
• space heating• air conditioning• industrial processes• drying • Greenhouses• Aquaculture• hot water• resorts and pools• melting snow
Geothermal greenhouse in Nigrita, Greece
Cultivation of spirulinaalgae using geothermalheat
Geothermal Greenhouses
How Direct Uses Work•Direct Sources function by sending water down a well to be heated by the Earth’s warmth.
•Then a heat pump is used to take the heat from the underground water to the substance that heats the house.
• Then after the water it is cooled is injected back into the Earth.
The power tube housing resembles a giant hypodermic needle. It has a modular nature, with the 10 megawatt unit measuring about 4 feet across and around 180 feet in length.
Geothermal tomato drying in Northern Greece
The finished product
Geothermal application inthe food industry
Ground Heat Collectors This system uses horizontal loops filled with circulating
water at a depth of 80 to 160 cm underground. Borehole Heat Exchange
This type uses one or two underground vertical loops that extend 150 meters below the surface.
Generation of Electricity is appropriate for sources >150oC
Dry Steam Plants: These were the first type of plants created. They use underground steam to directly turn the turbines.
Flash Steam Plants: These are the most common plants. These systems pull deep, high pressured hot water that reaches temperatures of 3600F or more to the surface. This water is transported to low pressure chambers, and the resulting steam drives the turbines. The remaining water and steam are then injected back into the source from which they were taken.
Binary Cycle Plants: This system passes moderately hot geothermal water past a liquid, usually an organic fluid, that has a lower boiling point. The resulting steam from the organic liquid drives the turbines. This process does not produce any emissions and the water temperature needed for the water is lower than that needed in the Flash Steam Plants (2500F – 3600F).
Casa Diablo
Geothermal fish drying in Northern Iceland
The finished product
Fish factory in Laugar, Iceland
Geothermal application inthe food industry
Hot Dry Rocks: The simplest models have one injection well and two production wells. Pressurized cold water is sent down the injection well where the hot rocks heat the water up. Then pressurized water of temperatures greater than 2000F is brought to the surface and passed near a liquid with a lower boiling temperature, such as an organic liquid like butane. The ensuing steam turns the turbines. Then, the cool water is again injected to be heated. This system does not produce any emissions. US geothermal industries are making plans to commercialize this new technology
Hot Rock
Geothermal Energy for the German Parliament
Heat- and Cold Storage, heat source waste heat from Combined Heat- and Power-Generation (CHP) during summertime
Shallow Geothermal Energy
Geothermal heating atthe Polar Circle: Hotel Storforsen, Älvsby, Sweden33 BHE each 160 m deep
Heatpum ps
(2 x 113 kW )prim ary circuit
Coolingm achines
refrigeratorsfreezers
33 Borehole heat exchangers each 160 m deep
H X H X
H X: H eat ExchangerE-boiler: E lectric heating (peak/back-up)TD : Tow el D ryingH W -St.: H ot W ater S torage
R echarge C ooling(room air)
secondary circ.
E -boiler
H X
Sw im m ing pool
F loorheating
H X
cold tap w ater
E-boiler
w arm tapw ater
TDH W -St.
DHW
Geothermal energy in Iceland
• 86% of houses in the country are heated by geothermal
• 17% of the electricity (200 MW) comes from geothermal
• Other uses include greenhouses, fish farming, industry, snow melting, swimming pools etc.
• Only a fraction of the potential is used
Total Primary EnergyConsumption in 2002
Thank you für your attention! See you all in Blue Lagoon, Iceland
Heating the alligator tank in Idaho – No swimming allowed
McDonald's World Famous French Fries are made
here… Beware of the Crocs
Direct uses for Geothermal water
A boy bathes in Beaujolais Nouveau at a Hakone Onsen Yunessun hot springs resort west of Tokyo in Japan. The young French wine is released on the third Thursday of November every year.
Geothermal Harmful Effects
Brine can salinate soil if the water is not injected back into the reserve after the heat is extracted.
• Extracting large amounts of water can cause land subsidence, and this can lead to an increase in seismic activity. To prevent this the cooled water must be injected back into the reserve in order to keep the water pressure constant underground.
• Power plants that do not inject the cooled water back into the ground can release Hydrogen Sulfide H2S, the “rotten eggs” gas. This gas can cause problems if large quantities escape because inhaling too much is fatal.
Geothermal Energy - Positive Attributes• Useful minerals, such as zinc and silica, can be
extracted from underground water.• Geothermal energy is “homegrown.” This will
create jobs, a better global trading position and less reliance on oil producing countries.
• US geothermal companies have signed $6 billion worth of contracts to build plants in foreign countries in the past couple of years.
• In large plants the cost is 4-8 cents per kilowatt hour. This cost is almost competitive with conventional energy sources.
•Geothermal plants can be online 100%-90% of the time. Coal plants can only be online 75% of the time and nuclear plants can only be online 65% of the time.•Flash and Dry Steam Power Plants emit 1000 times to 2000 times less carbon dioxide than fossil fuel plants, no nitrogen oxides and little SO2. •Geothermal electric plants production in 13.380 g of Carbon dioxide per kWh, whereas the CO2 emissions are 453 g/kWh for natural gas, 906g g/kWh for oil and 1042 g/kWh for coal.•Binary and Hot Dry Rock plants have no gaseous emission at all. •Geothermal plants do not require a lot of land, 400m2 can produce a gigawatt of energy over 30 years.
•Geothermal Heat Pumps:
- produces 4 times the energy that they consume.
-initially costs more to install, but its maintenance cost is 1/3 of the cost for a typical conventional heating system and it decreases
electric bill. This means that geothermal space heating will save the consumer money.
-can be installed with the help of special programs that offer low interest rate loans.
•Electricity generated by geothermal plants saves 83.3 million barrels of fuel each year from being burned world wide. This prevents 40.2 million tons of CO2 from being emitted into the atmosphere.
•Direct use of geothermal energy prevents 103.6 million barrels of fuel each year from being burned world wide. This stops 49.6 tons of CO2 from being emitted into the atmosphere.
Availability of Geothermal Energy
• On average, the Earth emits 1/16 W/m2. However, this number can be much higher in areas such as regions near volcanoes, hot springs and fumaroles.
• As a rough rule, 1 km3 of hot rock cooled by 1000C will yield 30 MW of electricity over thirty years.
• It is estimated that the world could produce 600,000 EJ over 5 million years.
• There is believed to be enough heat radiating from the center of the Earth to fulfill human energy demands for the remainder of the biosphere’s lifetime.