Renewable Energy IntegrationProfessor Stephen LawrenceLeeds School of BusinessUniversity of Colorado at Boulderhttp://www.eia.doe.gov/kids/energyfacts/sources/images/left.gifhttp://www.re-energy.ca/

AgendaCurrent and future sources of energyWhats best?Distributed Generation

World primary energy consumption BP website (BP.com)

World Energy Consumption to 2025http://www.eia.doe.gov/oiaf/ieo/world.html

Energy Forecasts by Sectorhttp://www.eia.doe.gov/oiaf/ieo/world.html

Primary energy consumed per capitaBP website (BP.com)

World Primary Energy per Capitahttp://www.newint.org/issue284/facts.html

Oil & Gas Production ForecastsBoyle, Renewable Energy, Oxford University Press (2004)

Global Fossil Carbon EmissionsWikipedia.org, Climate Change, Global Warming articles

Carbon Dioxide ConcentrationsWikipedia.org, Climate Change, Global Warming articles

Fossil FuelsBP website (BP.com)

Petroleumhttp://www.lakesoil.com.au/photo6.jpg

Natural Gashttp://www.energy.gov.ab.ca/222.aspwww.citypublicservice.com

Coalhttp://buildingsdatabook.eren.doe.gov/default.asp?id=fow&num=30

Tar Sandshttp://www.protectowire.com/applications/profiles/electric_shovels.htmhttp://www.aapg.org/explorer/2005/05may/dinning.cfm

Oil Shalehttp://nandotimes.nandomedia.com/ips_rich_content/896-shale_rock.jpghttp://geosurvey.state.co.us/Default.aspx?tabid=104

Problems with Fossil Fuels/CoalLarge source of atmospheric pollutionCreate carbon dioxide (CO2) when burnedImplicated in global warmingNitrous oxides (NOx) smog Sulfur dioxide (SO2) acid rainMeasurable amounts of radioactive materialNaturally present in coalMore than a nuclear power plant

Typical Coal-Fired Power Plant

CO2 Mitigation Optionshttp://www.netl.doe.gov

Carbon Sequestration Optionshttp://www.whitehouse.gov/omb/budget/fy2006/energy.html

Ocean Sequestrationhttp://www.lbl.gov/Science-Articles/Archive/sea-carb-bish.html

Polk Power Station Tampahttp://www.fossil.energy.gov/education/energylessons/coal/coal_cct5.html

FutureGen

Nuclear Energy

Nuclear Energy Consumption

US Production Cost Comparisonhttp://www.nei.org

Spent Fuel Cooling Poolhttp://www.uic.com.au/opinion6.html

Yucca Mountain Cross Sectionhttp://www.nrc.gov/waste/hlw-disposal/design.html

Transportation Concernshttp://www.nei.org/http://www.nei.org/index.asp?catnum=2&catid=84

Anti-Nuclear Adhttp://perth.indymedia.org/storyuploads/13114/en_4b.jpg

Hydropowerhttp://las-vegas.travelnice.com/dbi/hooverdam-225x300.jpg

Impacts of Hydroelectric Dams

Wind Energy

US Wind Energy Capacity

Recent Capacity Enhancements2006 5 MW 600

Costs Nosedive Winds Success38 cents/kWh3.5-5.0 cents/kWhLevelized cost at good wind sites in nominal dollars, not including tax credit

Chart1

0.38

0.15

0.1

0.08

0.06

0.04

0.035

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1980$0.38

1984$0.15

1988$0.10

1991$0.08

1995$0.06

2000$0.04

2005$0.04

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Solar Energyhttp://www.c-a-b.org.uk/projects/tech1.htmSolar Centre at Baglan Energy Park in South Wales

Large Scale Solarhttp://en.wikipedia.org/wiki/Solar_panel

Small Scale Solar

Solar Cell Production Volumehttp://sharp-world.com/solar/generation/images/graph_2004.gifSharp Corporation

PV Cell Efficiencieshttp://en.wikipedia.org/wiki/Image:Nrel_best_research_pv_cell_efficiencies.png

Solar Thermal Energyhttp://solstice.crest.org/renewables/re-kiosk/solar/solar-thermal/case-studies/central-receiver.shtml

Oceanic Energy

Tidal Turbines (Swanturbines)Direct drive to generatorNo gearboxesGravity baseVersus a bored foundationFixed pitch turbine bladesImproved reliabilityBut trades off efficiencyhttp://www.darvill.clara.net/altenerg/tidal.htm

Cross Section of a Tidal Barragehttp://europa.eu.int/comm/energy_transport/atlas/htmlu/tidal.html

Tapered Channel (Tapchan)http://www.eia.doe.gov/kids/energyfacts/sources/renewable/ocean.html

LIMPET Oscillating Water ColumnCompleted 2000Scottish IslesTwo counter-rotating Wells turbinesTwo generators500 kW max powerBoyle, Renewable Energy, Oxford University Press (2004)

Mighty Whale Design Japanhttp://www.jamstec.go.jp/jamstec/MTD/Whale/

Ocean Wave Conversion Systemhttp://www.sara.com/energy/WEC.html

World Oceanic Energy Potentials (GW)SourceTidesWavesCurrentsOTEC1SalinityWorld electric2World hydroPotential (est)2,500 GW2,70035,000200,0001,000,000

4,000Practical (est)20 GW5005040NPA42,8005501 Temperature gradients2 As of 19983 Along coastlines

4 Not presently available

Tester et al., Sustainable Energy, MIT Press, 2005

Geothermal Energy PlantGeothermal energy plant in Icelandhttp://www.wateryear2003.org/en/

Geothermal Site SchematicBoyle, Renewable Energy, 2nd edition, 2004

Methods of Heat Extractionhttp://www.geothermal.ch/eng/vision.html

Global Geothermal Siteshttp://www.deutsches-museum.de/ausstell/dauer/umwelt/img/geothe.jpg

Bioenergy Cyclehttp://www.repp.org/bioenergy/bioenergy-cycle-med2.jpg

Types of Biomass

Municipal Solid Wastehttp://www.eeingeorgia.org/eic/images/landfill.jpg

Landfill GassesBoyle, Renewable Energy, Oxford University Press (2004)

Hydrogen Economy Schematic

Electrolysis of Water (H2O)http://www.gm.com/company/gmability/edu_k-12/9-12/fc_energy/make_your_own_hydrogen_results.html

Hydrogen Economy

Transporting Hydrogen

UNIDO-ICHET Projectionhttp://www.unido-ichet.org/ICHET-transition.phpUNITED NATIONS INDUSTRIAL DEVELOPMENT ORGANIZATION INTERNATIONAL CENTRE FOR HYDROGEN ENERGY TECHNOLOGIES

What to do? Whats best?

Distributed Generation

Centralized vs. Distributed Generationhttp://www.nfcrc.uci.edu/fcresources/FCexplained/stationary.htm

US Net Energy Flowshttp://www.pharmaciaretirees.com/USenergyFlow99-quads_Internet.jpg

Power Generation Efficiencyhttp://www.pharmaciaretirees.com/distributed_generation.htm

Central Power Generation (today)Remote, Large, Expensive Long Distance Delivery Fossil Fuel Plants Waste Heat (Nuclear) Environment Unfriendly (Co2) Health Unfriendly (Nox, So2, Pm10, Hg) Nuclear Plants Waste Disposal Hydroelectric Plants Flooding Unreliable (2000-2003) 110 Grid Failures Cost $80-123 B./Yr Adds 29-45% To Electric Bill http://www.pharmaciaretirees.com/distributed_generation.htm

Current Power Industry - OpinionMonopolies Regulated No competition OssifiedExpensiveInefficient UnreliableUnfriendly Time has come for an energy revolution http://www.pharmaciaretirees.com/distributed_generation.htm

Distributed GenerationLocated next to user Range of energy sources Fossil fuel, waste gas, renewables, Hydrogen, nuclear Capacity kw Mw Economic benefits Waste heat used Lowers fossil fuel use Low investment Power failure losses eliminated Environmental/ health costs reduced Grid costs peak/capital Lower electric bills Flexibility of location Cogeneration Combined heat & power (CHP) Micropower http://www.pharmaciaretirees.com/distributed_generation.htm

Opinions Regarding DGDG Can Play a Key Role Where reliability is crucial- emergency capacity Alternative to local network expansion OpinionsHas potential to fundamentally alter structure and organization of our electric power system (IEA) Micropower passes nuclear as technology of choice for new plants globally. We really could be seeing the revival of Edisons dream (VVV) The era of monopolization, centralization and other regulation has started to give way to market forces in electricity (VVV) United States today931 DG Plants Deliver 72,800 MW 8.1% Of total US Powerhttp://www.pharmaciaretirees.com/distributed_generation.htm

Sources of DGSolar photovoltaic and thermalWind TurbinesHydroelectric (large scale and micro)GeothermalOceanicNuclearFossil FuelsCombined Heat & Power (CHP)http://www.pharmaciaretirees.com/distributed_generation.htm

CG vs. DG TodayCGDG Waste Energy %6710 Delivered Electricity %3390 Total Costs ($) Generation 4.25.2 T & D 6.60.6 Total 10.85.8 CO2X0.5X Oil Equivalent (BB)Y-122 Fossil Fuel Sales (Trillions $)Z-2.87 http://www.pharmaciaretirees.com/distributed_generation.htm

CG vs. DG in 2020CGDG Capital$B831504 Total Power Cost$B14555 Unit Power Cost /kWh8.65.5 EmissionsCO2X0.5X NOxA0.4A SO2B0.1B http://www.pharmaciaretirees.com/distributed_generation.htm

Enabling DG Technologies

MicroturbinesLow to moderate initial capital cost Fuel flexibility, burn either gaseous (natural gas, propane, biogases, oil-field flared gas) or liquid fuels (diesel, kerosene) Heat released from burning the fuel also providing heating and cooling needs (CHPExtremely low air emissions NOx, CO, and SOx Continuous operating even during brownout or blackoutA cutaway of a microturbine; 30 and 60-kilowatt units have just one moving part a shaft that turns at 96,000 rpm.

Microturbine Systemshttp://www.wapa.gov/es/pubs/esb/2001/01Jun/microturbine.htmhttp://www.cleanenergyresourceteams.org/microturbines.html

Micro-Hydrohttp://www.itdg.org/?id=micro_hydro_expertisehttp://www.greenhouse.gov.au/yourhome/technical/fs46.htm

Porker Power Lamar Coloradohttp://www.state.co.us/oemc/programs/distributed/Video

Distributed Generation Summary

Advantages of DGLocal positioning avoids transmission and distribution losses Generation adjacent to loads allows convenient use of heat energyCombined heat and power (CHP)Local positioning enables available sources of energy to be used, Waste products or renewable resources may be easily utilized to supplement fossil fuels Local positioning allows the use of available single or three phase generation http://www.rglsolutions.com/Distributed_Generation.htm

Disadvantages of DGDisadvantagesConventional distribution systems need adequate protection in order to accommodate exchange of power Signaling for dispatch of resources becomes extremely complicated Connection and revenue contracts are difficult to establish Issues with DGThe use of Net Power in certain areas of the USPower companies must by power from distributors a market rates IEEE 1547 standard, still under formulation Standard for interconnecting distributed resources with electric power systems Safety concerns with energy generated from multiple sources System protection under two way exchange of power http://www.rglsolutions.com/Distributed_Generation.htm

Extra Slides

Ramgen Fossil Fuel Generatorhttp://www.netl.doe.gov/technologies/coalpower/distgen/ramgen.html

Developing Cleaner Coal TechnologiesCarbon sequestration is a family of methods for capturing and permanently isolating carbon dioxide. Sequestration of carbon dioxide emissions from coal could help retain coals strategic value as a low-cost, abundant, domestic fuel. The 2006 Budget provides $286 million for the Presidents Coal Research Initiative to improve the environmental performance of coal power plants by reducing emissions and improving efficiency. This includes $68 million for the Clean Coal Power Initiative, of which $18 million is allocated to continue development of the FutureGen coal-fueled, zero-emissions, electricity and hydrogen generation project announced by the President in February 2003. FutureGen is guided by an industry and international partnership that will work cooperatively on research, development, and deployment of technologies that will dramatically reduce air pollution from coal-fueled electricity generation plants, generate hydrogen, and capture and store greenhouse gas emissions. The Budget ensures that unexpended funds available from prior years clean coal projects are available to fund future clean coal activities, beginning with FutureGen. The Budget also increases funding for research and development of other clean coal technologies, such as Integrated Gasification Combined Cycle systems, carbon sequestration, and next-generation turbines. One of the most promising places to sequester carbon is in the oceans, which currently take up a third of the carbon emitted by human activity, roughly two billion metric tons each year. The amount of carbon that would double the load in the atmosphere would increase the concentration in the deep ocean by only two percent. Two sequestration strategies are under intense study at the Department of Energy's Center for Research on Ocean Carbon Sequestration (DOCS), where Jim Bishop of Berkeley Lab's Earth Sciences Division is codirector with Livermore Lab's Ken Caldeira. One is direct injection, which would pump liquefied carbon dioxide a thousand meters deep or deeper, either directly from shore stations or from tankers trailing long pipes at sea.

"At great depths, CO2 is denser than sea water, and it may be possible to store it on the bottom as liquid or deposits of icy hydrates," Bishop explains. "At depths easy to reach with pipes, CO2 is buoyant; it has to be diluted and dispersed so it will dissolve."What happens to carbon dioxide introduced into the ocean in this way may soon be field-tested in Hawaii. Over a two-week period researchers plan to inject 40 to 60 metric tons of pure liquid CO2 over 2,500 feet deep in the ocean near the Big Island.One variable they will be measuring is acidity. Water and carbon dioxide form carbonic acid, "but once diluted in sea water, carbonic acid is not the dominant chemical species," Bishop says, "because of seawater's high alkalinity and buffering capacity." If calcium carbonate sediments are involved, acidity is even less. "Think of Tums," he suggests.Fertilizing the oceanThe other major approach to sequestration is to "prime the biological pump" by fertilizing the ocean. Near the surface, carbon is fixed by plant-like phytoplankton, which are eaten by sea animals; some eventually rains down as waste and dead organisms. Bacteria feed on this particulate organic carbon and produce CO2, which dissolves, while the rest of the detritus ends on the sea floor."There are areas of the ocean that are rich in nutrients like nitrogen and phosphorus but poor in phytoplankton," says Bishop. "Adding a little iron to the mix allows the plankton to use the nutrients and bloom. The energy for the process is supplied by sunlight. Already commercial outfits are dropping iron filings overboard, hoping to increase fisheries -- meanwhile claiming they are helping to prevent global warming." THE GLOBAL CARBON CYCLE AND THE ROLE OF THE OCEANIn fact, Bishop explains, "if the excess fixed carbon in plants is eaten by fish near the ocean surface, the net effect is no gain. And in every part of the ocean there are open mouths."No one really knows where the carbon trapped by fertilization ends up. In one iron-fertilization experiment in warm equatorial waters, chlorophyll increased 30-fold in a week, and there was increased carbon sedimentation down through 100 meters. But the bloom shortly dissipated, the fate of the carbon in deeper waters wasn't followed, and long-term effects weren't measured.In a more recent experiment in cold Antarctic Ocean waters the plankton bloom persisted much longer. Seven weeks after the experiment ended a distinct pattern of iron-fertilized plankton was still visible from space -- "which means the fixed carbon was still at the surface."Bishop says that "people who want to add iron think the particulate matter will fall straight to the bottom; I have sampled natural plankton blooms, and I have not seen that happen. These guys have a potentially effective method of sequestering carbon, but as yet there is no scientific basis for their claims."One of the most advanced - and cleanest - coal power plants in the world is Tampa Electric's Polk Power Station in Florida. Rather than burning coal, it turns coal into a gas that can be cleaned of almost all pollutants. To ensure that no significant environmental releases occur over periods of tens of thousands of years, a 'multiple barrier' disposal concept is used to immobilise the radioactive elements in high-level and some intermediate-level wastes and isolate them from the biosphere. It involves stabilising, containment and finally, remote disposal. Details are in several UIC publications, along with some information on how the waste materials are actually handled and stored in different countries Wind turbines technology generally falls into two categories: small, or distributed turbines that provide power directly to their owner, and large, or utility-scale turbines that provide wholesale power. The small turbines (such as the one of the far right of this page), range from several watts in capacity to 10-50 kilowatts. The utility-scale turbines range from about 660 kilowatts to 1.8 megawatts. Offshore turbines can be larger, in the 2-megawatt range.

A 10-kW turbine has a rotor diameter of 7 meters (23 feet). It is usually mounted on a 50-60-foot tower, and can produce about 16,000 kWh annually, more than enough to power a typical household.

A 1.5-MW turbine has a rotor diameter of 65 - 77 meters (213-253 feet). They are typically installed on towers that are at least 65 meters (213 feet) tall. A 1.5-Mw turbine can produce more than 4.3 million kWh per year, enough to power more than 400 average U.S. housesholds. Vestas V52 850 kW, 52 m rotor diameter, avg. 55 m hub heightVestas V80 1.8 MW, 80 m rotor diameter, avg. 67 m hub heightREPower Systems 5M 5 MW, 126 m rotor diameter, up to 120 m hub heightStatue of Liberty 305 feet from ground to torchThe cost of producing electricity from wind energy has declined more than 80%, from about 38 cents per kilowatt-hour in the early 80s to a current range of 3 to 6 cents per kilowatt-hour (KWh) levelized over a plant's lifetime.

In the not-too-distant future, analysts predict, wind energy costs could fall even lower than most conventional fossil fuel generators, reaching a cost of 2.5 cents per kWh.

This dramatic reduction in the cost of energy from wind plants can be attributed largely to technological improvements and economies of scale achieved by manufacturing more and larger wind turbines. This will be discussed in more detail in the following slides.

A solar panel in Marla, Cirque de Mafate, Runion

Larger solar arrays can provide electricity to habitations in isolated, well-lighted areas

http://en.wikipedia.org/wiki/Solar_panelThis 10 megawatt solar thermal central receiver power plant, Solar I, was originally built as a test facility. The initial six-year test span proved a success and outlines to upgrade the technology have been approved. In Solar II, an innovative new power storage technology will be implemented that will enable the system to supplement the local utility's demand for electricity during peak load hours in the night.The "Swanturbines" design is different to other devices in a number of ways. The most significant is that it is direct drive, where the blades are connected directly to the electrical generator without a gearbox between. This is more efficient and there is no gearbox to go wrong. Another difference is that it uses a "gravity base", a large concrete block to hold it to the seabed, rather than drilling into the seabed. Finally, the blades are fixed pitch, rather than actively controlled, this is again to design out components that could be unreliable.

http://www.darvill.clara.net/altenerg/tidal.htmAnother promising type of wave energy power plant is a shoreline-based system called the Tapered Channel (Tapchan). The principle here is capital intensive yet has potential due to its ruggedness and simplicity. A tapering collector funnels incoming incoming waves in a channel. As the wave travels down the narrowing channel it increases in height till the water spills into an elevated reservoir. The water trapped in the reservoir can be released back to the sea similar to conventional hydroelectric power plants to generate electricity [1]. The advantage of this particular system lies in its ability to buffer storage which dampens the irregularity of the waves. However, the Tapchan system does require a low tidal range and suitable shoreline topography -limiting its application world-wide. A demonstration prototype of this design has been running since 1985 and plans are under consideration to build a commercial scale plant in Java [8].

http://www.oceansatlas.com/unatlas/uses/EnergyResources/Background/Wave/W2.htmlAnother notable example of an OWC is the Mighty Whale. It is the worlds largest offshore floating OWC and was launched in July 1998 by the Japan Marine Science and Technology Center. This prototype, moored facing the predominant wave direction, has a displacement of 4,400 tons and measures 50m long. The Mighty Whale has three air chambers that convert wave energy into pneumatic energy. Wave action causes the internal water level in each chamber to rise and fall, forcing a bi-directional flow over an air-turbine to generate energy. The resulting electricity is supplied mainly to the nearby coastal areas. Storage batteries onboard ensure that electricity is available even during periods of reduced wave activity. It is projected that a row of such devices could be used to supply energy to fish farms in the calm waters behind the devices, and aeration/purification of seawater [7].

http://www.oceansatlas.com/unatlas/uses/EnergyResources/Background/Wave/W2.htmlThis technology builds upon SARA's pioneering Ocean Wave Energy Conversion system, awarded US Patent 5,136,173; 1992. Unlike alternative concepts that make use of cumbersome intermediate mechanical stages, SARA's approach uses direct conversion of mechanical fluid energy into electricity, via a highly efficient magnetohydrodynamics (MHD) process. Product:Rapidly-deployable Wave-powered MHD Electric Generator for the US NavyLow-cost commercial power for coastal communities. Benefits:Almost no moving parts. No gears, no levers, no turbines, no drive belts, no bearings, etc. Direct, local, and efficient conversion of fluid motion into electricity, with no intermediate mechanical stages. Highly-compatible with very-strong, but slow-moving, driving forces (ocean waves, for example).

http://www.wateryear2003.org/en/ev.php-URL_ID=4930&URL_DO=DO_PRINTPAGE&URL_SECTION=201.htmlhttp://www.eia.doe.gov/cneaf/solar.renewables/page/mswaste/msw.jpghttp://www.eeingeorgia.org/eic/images/landfill.jpgThe term Hydrogen Economy refers to the infrastructure to support the energy requirements of society, based on the use of hydrogen rather than fossil fuels.The concept of using hydrogen as an energy system is not new; it has previously been used both industrially and domestically (town gas - 50% hydrogen was used in the UK until the 1950's). Interest in hydrogen as a vehicle fuel dates back to the 1800's but heightened in the 1970's with the oil crises and with technological advances in the 1980's.

Hydrogen is a good candidate for reducing emissions since when it is reacted with oxygen it produces only water as the reaction product. Hydrogen can be used to provide electricity and heat either through use in a fuel cell or combustion. A fuel cell generates electricity by combining hydrogen with oxygen from air; the only by-product is water. Hydrogen can also be burned in an internal combustion engine in the same way as petrol or natural gas. This produces water as the main by-product, however, small amounts of oxides of nitrogen (air pollutants) are also produced.Unlike oil, gas and coal hydrogen doesn't exist in large quantities in nature in a useful form. Like electricity it is an energy carrier, which must be produced using energy from another source. Hydrogen, however, has the advantage that it can be stored more easily.Today, nearly half the hydrogen produced in the world is derived from natural gas via a steam-reforming process. The natural gas reacts with steam in a catalytic converter. The process strips away the hydrogen atoms, leaving carbon dioxide as the by-product. Therefore, in the future, hydrogen must be produced from renewable energy sources.Ahypothetical supply chain for a 'hydrogen-based economy'. (Image courtesy of theCenter for Energy, Environmental, and Economic Systems Analysisat Argonne National Laboratory.) Following the proposal by the Hydrogen Romantics of the Hydrogen Energy System, one of their first actions was to establish the International Association for Hydrogen Energy,IAHE . IAHE was established with the aim of promoting conversion to the Hydrogen Economy by informing the public in general, along with energy and environment scientists and decision makers in particular about the advantages and benefits of the Hydrogen Energy System. In January 1975, IAHE started the publication of its scientific journal, the International Journal of Hydrogen Energy, IJHE, and now publishes some 15 issues a year. Starting in 1976, IAHE began organizing the biennial World Hydrogen Energy Conferences (WHECs). In parallel with the International Association for Hydrogen Energy, a growing number of national hydrogen energy organizations have been established around the world which organize their own publications together with national and regional conferences. During the first quarter century, from 1974 through 2000, utilising the research and development activities in universities and energy related industries, and through information dissemination activities, such as conferences and publications, the foundations of the Hydrogen Energy System were established. By the year 2000, the transition to the Hydrogen Economy had started. In Japan and in the U.S.A., hydrogen fueled cars are available for leasing. In Europe, the Americas and Australia, Rapid Transport Authorities have started operation of fleets of hydrogen fueled buses. Several types of hydrogen fuel cells as well as hydrogen hydride electric batteries are available commercially for electricity generation. Many countries have initiated programmes for roadmaps for conversion to the Hydrogen Economy. However, present modeling studies indicate that if no incentives are provided for clean energy, full transition to the Hydrogen Economy will take three quarters of century. Slide 2 (Casten, Skeptical Inquirer v29 no1 Jan/Feb 2005 p.25) Let us look at the efficiency of US plants from 1880 to the present. This is a rough plot of average efficiency of US plants over this period. Efficiency is defined as the conversion of the energy source to useful heat, as shown in the upper section, and electricity, as shown in the lower section. We see that total efficiency reached a peak in 1910 and fell to an average of 33% over the next 50 years, despite the fact that electrical efficiency rose during that period. There was no change over the next 40 years with an average efficiency of 33%. Before 1910, electricity was provided by plants located next to the user, so that heat generated was not wasted. This was Edisons way. We now refer to this as distributed generation (DG). After 1910, large remote plants started to take over. We refer to this as central generation (CG). The circles show CG plants with improved efficiency and the squares some DG plants of recent vintage. Slide 3 This slide summarizes the characteristics of Central Generation. Large, expensive plants benefit from economy of scale, but there is a price to pay in costs of long distance delivery via the grid, described as the largest machine built by man, now in a sclerotic condition. Fossil Fuel Plants waste heat, as do Nuclear. FF plants are environmentally and health unfriendly, giving off CO2 and polluting gases. Nuclear plants do not generate any of these gases, but nuclear and hydroelectric plants have their own environmental problems. CG plants are unreliable. In the years 2000 to 2003 there were 110 grid failures, 11 of which involved over 0.5 million people. In 2003 the cost of electricity to end users was $272 billion. Grid failures added somewhere between $80 to $123 billion to this bill. Recent hurricanes in Florida cost utilities 1 billion dollars to replace 30,000 poles, 22000 transformers and 3,000 miles of wire. CG plants are monopolies, owned privately and by states and municipalities. They are highly regulated, and for many years without competition. One reason for 40 years of no improvement stems from the regulation that all cost-saving improvements must be passed on to the customer. The incentive for improvement and profit is nullified. At the bottom of slide 3 are some adjectives that are used by critics to describe Central Generation. If we are to have a revolution, we should have something in mind that is better, and we do, Distributed Generation. But first, lets see how a typical coal CG plant works, using the one at Apollo Beach Florida as an example. Slide 3 This slide summarizes the characteristics of Central Generation. Large, expensive plants benefit from economy of scale, but there is a price to pay in costs of long distance delivery via the grid, described as the largest machine built by man, now in a sclerotic condition. Fossil Fuel Plants waste heat, as do Nuclear. FF plants are environmentally and health unfriendly, giving off CO2 and polluting gases. Nuclear plants do not generate any of these gases, but nuclear and hydroelectric plants have their own environmental problems. CG plants are unreliable. In the years 2000 to 2003 there were 110 grid failures, 11 of which involved over 0.5 million people. In 2003 the cost of electricity to end users was $272 billion. Grid failures added somewhere between $80 to $123 billion to this bill. Recent hurricanes in Florida cost utilities 1 billion dollars to replace 30,000 poles, 22000 transformers and 3,000 miles of wire. CG plants are monopolies, owned privately and by states and municipalities. They are highly regulated, and for many years without competition. One reason for 40 years of no improvement stems from the regulation that all cost-saving improvements must be passed on to the customer. The incentive for improvement and profit is nullified. At the bottom of slide 3 are some adjectives that are used by critics to describe Central Generation. If we are to have a revolution, we should have something in mind that is better, and we do, Distributed Generation. But first, lets see how a typical coal CG plant works, using the one at Apollo Beach Florida as an example. Slide 5 Now back to the energy revolution, Distributed Generation. The key feature is that these plants are located next to the user so that heat generated can be utilized. Many energy sources are used, including waste gases from land fills, renewables and even nuclear. Nuclear is a DG source aboard naval vessels where heat and electricity are utilized. Capacities vary from KW to MW. Using waste heat lowers fossil fuel use. Whereas CG plants benefit from economies of scale, DG plants with low investment costs benefit from economies of mass production. Power failure and environmental health costs are reduced or eliminated. Many DG units are connected to the grid which permits peak-shaving, and adding electrical energy to the grid when DG energy is not needed. In addition, utilities benefit when their grid does not reach a remote area where electricity is needed. It is cheaper to set up a DG unit than to extend the grid. Another advantage of DG is flexibility of location. They can be placed on ski slopes, farms, green houses etc. The Conde Nast building in Times Square uses solar panels and fuel cells to lower electric bills and the new 1776 building planned for ground zero will be fitted with a wind turbine for the same purpose. Slide 6 Slide 6 provides quotes from IEA (International Energy Agency) and Power to the People by Vijay V Vaitheeswaran. There are 931 DG plants that deliver 72,800 megawatts or 8.1% of the US total. Slide 7 Energy sources and equipment for DG vary, as shown in the top portion of this slide. Combined heat & power equipment using fossil fuels (CHP) has been around for over 30 years. Principles are similar to those used in Apollo Beach. Chemical energy is converted to heat energy to mechanical energy to electrical energy. Microturbines are a fairly recent development, following a pattern that smaller is better, as seen in many other fields. Pre-heated air is mixed with natural gas and combusted. The gases rotate a turbine which drives a compressor which feeds gases to a 2nd turbine which drives a generator producing electricity. Heat developed is used to pre-heat air going in as well as for other useful purposes. These units are the size of a refrigerator and have one moving part (turbine, compressor and generator on a single shaft) They are quiet, clean, can run continuously and are designed to last for 10 years. The technology which made microturbines possible is the development of air bearings that permit revolutions as high as 100,000 rpm. Slide 8 The next slide compares CG and DG for world growth to deliver 4,368 gigawatts in the hypothetical situation where CG or DG plants are used exclusively. This amounts to about 5 times present US electrical generation. Despite the fact that CG plants must generate more electricity to deliver 4,368 GW, generation costs are lower by $1 trillion. However T & D costs are considerably less for DG plants, with a net benefit of $5 trillion for the DG approach. CO2 is cut in half, and the savings in oil equivalent is 122 billion barrels, which is about one half of Saudi Arabias oil reserves. Fossil fuel savings equal $2.87 trillion. Slide 9 Casten and coworkers developed a similar comparison for USA growth to the year 2020. Here we see a 3 cent/KWh advantage for DG in the cost of power produced and reductions in CO2 and polluting gases Microturbinesgas- or liquid-fuel-fired turbine-generator units with an electrical output between 30 and 500 kilowattsare being used increasingly for 24/7 onsite power generation. And many areas of the world will very likely see a major increase in microturbine-based onsite power generation over the next five to 10 years. A cutaway of a Capstone microturbine. The company's 30 and 60-kilowatt units have just one moving parta shaft that turns at 96,000 rpm.Since making their commercial debut a mere five years ago, microturbines have been installed with considerable success in office and apartment buildings, hotels and motels, supermarkets, schools and colleges, office and industrial parks, small industries, and numerous other facilities both in the US and abroad. They provide not only electricity, but the thermal energy to provide for all heating and cooling needs.The reasons for the growth in microturbine installations lie in the intrinsic advantages of this technology, including:Low to moderate initial capital cost Fuel flexibility, allowing them to burn either gaseous (natural gas, propane, biogases, oil-field flared gas) or liquid fuels (diesel, kerosene) Heat released from burning the fuel not only generating electricity, but also providing all heating and cooling needs for a facility through cogeneration, combined heat and power (CHP), and combined cooling, heat and power (CCHP) Extremely low air emissions for NOx, CO, and SOx The ability for a facility to continue operating even during a regional power brownout or blackout, offering greater energy reliability

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One of the most striking technical characteristics of micro turbines is their extremely high rotational speed. The turbine rotates up to 120 000 rpm and the generator up to 40 000 rpm. Individual units range from 30-200 kW but can be combined readily into systems of multiple units. Low combustion temperatures can assure very low NOx emissions levels. They make much less noise than an engine of comparable size. Natural gas is expected to be the most common fuel, but landfill gas, or biogas can also be used [1]. The main disadvantages of micro turbines at this stage are its short track record and high costs compared with gas engines http://www.energysavingnow.com/paper/dgindia/

These systems, which are designed to operate for a minimum of 20 years, are usually 'run-of-the-river' systems.This means they do not require a dam or storage facility to be constructed but simply divert water from the stream or river, channel it in to a valley and 'drop' it in to a turbine via a penstock (pipeline).This type of hydro generating thus avoids the damaging environmental and social effects that larger hydroelectric schemes cause.Cost for a typical micro-hydro system varies depending on the project. As a guide every kilowatt of power generated cost around 800. A 6-kilowatt system, enough to drive an electric mill and provide light for a community of about 500, would cost approximately 4,800. Experience shows that community capital (in labour and cash), financial credit and improved income makes these schemes economically viable and sustainable.Besides providing power for domestic lighting and cooking needs, village hydro schemes can also be used for charging batteries or for income generating activities like grain milling, depending on the needs of the community.The Fossil Energy R&D program is committed to searching for promising new ideas for low-cost, low-pollutant power generation. Three Ramgen technologies are under examination: 1) the Rampressor, a compressor product; 2) the Rampressor-Turbine, a combination of the Rampressor with the combustor and turbine stages of a turbine engine to gain compression advantages in generating electricity; and, 3) the Ramgen Engine which maximizes the use of ramjet technology to produces electricity. The design of the Ramgen compression technology represents a unique application of well-established ramjet principles to air and gas compression. In an aerospace propulsion ramjet, air is ingested into the engine inlet at supersonic speeds caused by the forward motion of the airplane or missile. The air is rammed into a smaller opening between a center-body and the engine sidewall generating a series of shock waves. These shock waves compress and slow the air to subsonic speeds while, at the same time, dramatically raising working flow pressure and temperature.A comparable effect is achieved in a stationary platform by passing an accelerated flow of air over raised sections machined into the rim of a rotor disc. Combined with high rotation rate of the rotor, this produces a supersonic flow relative to the rotor rim. Interaction between the raised sections on the rim (which are rotating at supersonic speeds) and the stationary engine case creates a series of shock waves that compress the air stream in a manner similar to ramjet inlets on a supersonic missile or aircraft. There are several important characteristics of Ramgens compression technology: the process is more efficient than other compression technologies; the technology is relatively simple and products utilizing it are expected to be inexpensive to build and maintain; the technology is designed to produce a compressor and engine smaller and lighter than competing technologies; and the technology is designed to be scaled over a range from 200 kW to 10 MW. As a result of these characteristics, Ramgens shock wave compression technology has the potential to be used in many applications: as an air and gas compressor for industrial processes; in refrigeration and air conditioning; on gas pipelines; as a gas compressor for high pressure gas turbines; or, as a replacement for an axial compressor on the front stage of an industrial gas turbine. Approximately 17% of the electrical use in the U.S. is for compression, and DOE has identified increasing efficiency in compression as a priority. The Rampressor is projected to increase efficiency in comparably sized compressors by 10 percentage points or more. Due to the small size, low weight and the elimination of the intercooler, the capital and maintenance costs are expected to be lower than current compressors. The Rampressor Turbine Engine is projected to be available in a 200 kW to 5 MW size range, achieve 40 percent plus simple cycle efficiency in all sizes; have less than 5 ppm NOx; be small, quiet, and reliable with capital costs in the range of $500 kW of capacity; and have an exhaust heat flow resulting in system efficiency of 80% or higher in combined heat and power applications.

http://www.netl.doe.gov/technologies/coalpower/distgen/ramgen.html