Ocean Energy Basics. The ocean contains two types of energy: thermal energy from the sun's heat, and mechanical energy from the tides and waves.

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1 Ocean Energy Basics The ocean contains two types of energy: thermal energy from the sun's heat, and mechanical energy from the tides and waves.

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3 Floating waveenergy generators Buoys and Snakes

4 TIDAL POWER-A 300-kW turbine prototype, developed by Marine Current Turbines Ltd., was installed over a year ago in Britain's Bristol Channel to take advantage of the 5-knot tidal flow. axial-flow turbines

5 Cross-flow turbine

6 Tidal Turbines

7 The Rance, France tidal power plant, power from the ocean The Rance tidal power plant is capable of turbining both when the basin is filled and when it is emptied, at high tide and low tide. The blades of the turbines can change directions according to the direction of the current The 24 bulb sets in the Rance facility have impressive technical credentials: 5.3 metres in diameter, 470 tonnes in weight and a unit capacity of 10 MW.

8 The Rance, France tidal power plant, power from the ocean In November 1996, the tidal power plant celebrated its thirtieth anniversary of operation. For 30 years, the 24 turbines of the Rance facility have shown outstanding reliability. The power plant has operated without major incidents or breakdowns for 160,000 hours and generated 16 billion kwh at the price of 18.5 centimes per kilowatt-hour, a highly competitive price and one that is lower than Electricité de France's average generation costs.

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10 East River Tidal Power In December 2002 and January 2003, Verdant Power successfully deployed a prototype turbine system in the East River in New York City The surface-mounted axial flow turbine, with 10-foot diameter rotors, generated up to 16 kw of power. A yaw system allowed the system to rotate and capture

11 East River Tidal Power The project's ultimate goal is to construct a 5 to 10 megawatt power field. It will be populated with several hundred turbine units, mounted on monopiles affixed to the bottom of the tidal basin.

12 In an open-cycle OTEC system, warm seawater is the working fluid. The warm seawater is "flash"- evaporated in a vacuum chamber to produce steam at an absolute pressure of about 2.4 kilopascals (kpa). The steam expands through a low-pressure turbine that is coupled to a generator to produce electricity. The steam exiting the turbine is condensed by cold seawater pumped from the ocean's depths through a cold-water pipe. If a surface condenser is used in the system, the condensed steam remains separated from the cold Ocean Thermal Energy Conversion

13 Ocean Thermal Energy Conversion In the closed-cycle OTEC system, warm seawater vaporizes a working fluid, such as ammonia, flowing through a heat exchanger (evaporator). The vapor expands at moderate pressures and turns a turbine coupled to a generator that produces electricity. The vapor is then condensed in another heat exchanger (condenser) using cold seawater pumped from the ocean's depths through a coldwater pipe. The condensed working fluid is pumped back to the evaporator to repeat the cycle. The working fluid remains in a closed system and circulates

14 Ocean Thermal Energy Conversion A hybrid cycle combines the features of both the closedcycle and open-cycle systems. In a hybrid OTEC system, warm seawater enters a vacuum chamber where it is flashevaporated into steam, which is similar to the open-cycle evaporation process. The steam vaporizes the working fluid of a closed-cycle loop on the other side of an ammonia vaporizer. The vaporized fluid then drives a turbine that produces electricity. The steam condenses within the heat exchanger and provides desalinated water.

15 San Gorgonia Pass, California

16 Windiest Locations in the U.S. Figure Source: After Jon G. McGowan, Tilting Toward Windmills, Technology Review, July 1993, p. 41, MIT.

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18 Wind turbines extract energy from the wind by transferring the momentum of passing air to the rotor blades. Energy is thus concentrated into a single rotating shaft. The power in the shaft can be used in many ways; modern turbines convert it into electricity. Wind Energy

19 Wind Energy Wind energy costs have fallen dramatically in recent years: costs in the Netherlands fell by a factor of three between 1985 and 1995 and in Germany by a third between 1991 and Wind farms due to be developed within the next five years in the UK should generate electricity at costs as low as 3ECU cents/kwh. Wind energy technology is highly reliable and routinely achieves availabilities of 98% and over, but operating experience, particularly with the larger (600kW-plus) machines, is limited to a few years. There is no experience of machines of this size over the projected lifespans of 20 years or more

20 TOTAL INSTALLED U.S. WIND ENERGY CAPACITY: 6,740 MW as of Jan 24, 2005

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22 Tehachapi, California 605 MW Installed in 1980 s and 1990 s

23 Tehachapi, California

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27 There are more than 4000 wind turbines in San Gorgonia Pass

28 Somerset, Pennsylvania

29 Wind Power Characteristics Wind Powe r Class Power* (w/m2) Speed* (mph) Commercial Viability Very Poor Poor Marginal Good Very Good Excellent *Wind characteristics at 50 meters above ground.

30 Wind Power Economics Since 1980, the price of wind power has dropped from 40 cents per kilowatt-hour to 4-7 cents today, only slightly higher than fossil fuel and well below the 20-cent cost for solar electricity Between 1981 and 2000, windmills improved in power output by 125 times while increasing only 20 times in cost.

31 750 kw NEG Micon Turbine in Moorhead Minnesota.

32 Vindby Wind Farm Lolland, Denmark

33 Proposed Long Island Wind Farm The facility will consist of 40 state-of-the-art wind turbines capable of producing 140 megawatts of power enough electricity to serve approximately 44,000 average homes on Long Island

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35 Simulated View from Robert Moses State Park

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38 Geothermal Power Plants Worldwide Figure Source: Figure prepared by L.J. Patrick Muffler and Ellen Lougee, U.S. Geological Survey; plate-tectonic boundaries supplied by Charles DeMets, University of Wisconsin at Madison.

39 Geothermal Potential

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42 Lone Star Geyser in Yellowstone Figure Source:Courtesy of Carla W. Montgomery.

43 Mammoth Terraces in Yellowstone Figure Source:Courtesy of Carla W. Montgomery.

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48 Aerial View of the Geysers Geothermal Area Figure 14.23B Source: Photograph by R.E. Wallace, USGS Photo Library, Denver, CO.

49 The Geysers Power Plant in CA Figure 14.23A Source: Photograph by R.E. Wallace, USGS Photo Library, Denver, CO.

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53 Pumpernickel Geothermal Site, Nevada

54 Nevada Geothermal Power Inc. is developing renewable geothermal energy projects in Nevada where additional electrical generation capacity is needed to meet existing demand for power. Nevada Geothermal plans to develop an initial 30 megawatt geothermal power plant at Blue Mountain, subject to further resource drilling and feasibility studies. To date the company has received US $1.84 million in grants from the U.S. Department of Energy for cost share drilling at the Blue Mountain geothermal site in northern Nevada and recently Pumpernickel Valley geothermal site. Generation of electricity from geothermal reservoirs is economically viable. Currently the state of Nevada has 12 geothermal power plants totaling 244 megawatts of power capacity. Electricity production from renewable sources is expected to triple in the coming decade. Federal Renewable Energy Production Tax Credit (US1.9 cents per kwh) has been expanded to geothermal.

55 Crump Geyser, Oregon, 1959

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58 Crump Geyser Source water temperatures of 185 degreec/365 degreef and the resource potential was estimated at 85 MW. The Crump Geyser is within the northern part of the Basin and Range rift terrain which also hosts the Blue Mountain geothermal project. The Basin and Range region is characterized by relatively thin earth crust, high heat flow and deep penetrating extensional faults.

59 Crump Geyser The Crump Geyser area is located in Warner Valley, Lake County, near the hamlet of Adel, which is 53 km east of Lakeview, Oregon, on Highway 140, and 287 km northwest from Winnemucca, Nevada. At Crump Geyser, a 1680-foot deep well drilled by Magma Power company (in 1959) spontaneously erupted a few days after it was abandoned by Magma. The well flowed 500 gallons/minute (30 litres/second) of boiling water 200 feet into the air continuously for 6 months before reverting to a spectacular geyser erupting at regular intervals. In the 1960's the well was plugged with rocks stemming the geyser flow, however boiling water still rumbles at depth and boiling water bubbles to the

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65 Biomass Bio fuel Waste combustion Bio gas (methane) Ethanol Bio diesel

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