Pebble Bed Modular Reactor

    PART ONE: PREAMBLE

    Nuclear Power Industry activities can be broadly divided into fuel cycle activities, reactor activities and support activities. Fuel cycle activities include uranium mining and milling to produce ore concentrates (yellowcake), conversion of uranium ore concentrates into uranium hexafluoride, uranium enrichment, fuel fabrication, spent fuel reprocessing and nuclear waste management, and the design and construction of fuel cycle facilities. Reactor activities include reactor design, licensing and construction, reactor operation, maintenance and decommissioning.

    AscenTrust, LLC. (The Company) and its strategic nuclear partners, own or control the intellectual property, the processes and the manufacturing facilities and possess the engineering, procurement, construction and fabrication capabilities to design, license and build an American based infrastructure for the manufacturing of all the systems and sub-systems required to build a safe, clean Nuclear Technology Pebble Bed Modular Reactor (NTPBMR) electric generating power plants. The Company will mandate that 85% of the supply chain for the components of the project be manufactured in the United States.

    Using only private funding, the company is working with the County Judges and Commissioners of Matagorda, Jefferson, Orange, Montgomery and Harris Counties, and will harness the support of the Governor of the State of Texas to design, license and build the main manufacturing plants required to fully implement the NTPBMR Technology.

    The environmentally benign aspects of nuclear power, compared to alternative energy sources are important to developing economies as well as Industrialized Nations. Our Nuclear Power Project can contribute significantly to the responsible use of natural resources found on the American Continent and create an energy production supply chain which is sustainable and has a very small carbon dioxide footprint. However, the Company and it’s nuclear industry partners are also aware of the serious safety and proliferation hazards associated with nuclear facilities and we are committed to developing the NTPBMR in a manner consistent with NRC and IAEA safety and non-proliferation standards.

    Both reactor and fuel cycle services rely upon a number of support activities, including consulting, legal services, parts manufacturing, fuel transportation and fuel supply brokers, research and development (R&D) institutions (government, enterprise or university-based) and industry bodies. The Company will work with Dr. Gary Sorensen and Mr. Howard Selman of The Living Space Initiative to flesh out the residential and commercial side of the support structures required for the successful implementation of this supply chain in the sixteen states belonging to the Southern States Energy Board, the epicenter of the project will be in Matagorda County, Texas.

    One of the most attractive facets of the NTPBMR project is the number of high value jobs which we will be able to create across the Supply Chain of the Nuclear Fuel Cycle. We estimate that we will be able to create more than 100,000, direct, permanent, high value jobs in Engineering, Research and Development, Manufacturing, Construction, etc. The multiplication factor for these types of jobs is more than five so that we can expect to create over 500,000 permanent jobs all across the Southern States.

    PART TWO: INTRODUCTION

    The ramp-up in gasoline prices in the summer of 2008 gave national prominence, once again, to the issues of energy supply and demand. The crisis highlighted our dependence on fossil fuels for the production of this electrical energy. The energy ethos in the U.S. has been, for a large part of the history of its growth in the 20th century : Not in my back yard.
    Increased demand coupled with a strict regulatory environment has stopped the licensing and construction of new power plants. The “crisis” apparently came and went and was soon forgotten. What it did accomplish however was a more lively discussion, in the most liberal area of the United States of America, of the importance of supply, recognizing the ever increasing demand as we electrify. In this discussion of demand came the realization that approximately 20% of the nation’s electricity was being generated by nuclear energy which was not subject to the escalating cost of natural gas that drove electricity prices far above what the public would tolerate.

    The net consequence of a number of factors, such as a faulty deregulation scheme that drove one of the major electric companies in California into bankruptcy, were rolling blackouts due to lack of generation at any price. Given that, in California, the construction of new plants of any type was frowned upon and the regulatory climate somewhat hostile, no company was interested in making generation investments.

    On a different but somewhat parallel track, in terms of energy use versus planetary environmental health is the slight increases in low levels of carbon dioxide (CO2) in the atmosphere over the last few years. The level of CO2, in the atmosphere, ranges from 250 parts per million to 350 parts per million. This carbon dioxide becomes part of what the environmentally involved scientist call “greenhouse” gases. These greenhouse gases absorb light in the infrared and prevent the re-emission of photons in the lower bands of frequencies which allows the earth to cool itself.This absorbed energy gets trapped in the atmosphere and is causing an increase in the mean global temperature of the earth.

    Increased carbon dioxide emissions in the atmosphere have increased the amount of rhetoric, often vitriolic, in reference to the existence and implications of increasing greenhouse gases in our environment due to the burning of these same fossil fuels.

    While the environmental ministers of nations from around the world seek to find ways to meet the 1992 Kyoto accords which call for reductions in CO2 and other greenhouse gases to 10% below 1990 levels, the reality almost 20 years later is that CO2 emissions have not decreased at all but increased by 10%.
    As everyone involved with nuclear technologies know, one of the key advantages of nuclear energy is that it is essentially a greenhouse-gas-emission-free technology. Yet, at its most recent meeting in Copenhagen, Denmark, the Conference of the Parties COP 15, these same environmental ministers voted to specifically exclude nuclear energy from helping address the global warming problem.

    Clearly, there is something wrong here since, in the United States, nuclear energy provided over 69% of the emission-free generation, far exceeding the 30% hydroelectric power. Solar and other renewable forms of energy provide the rest (~1%).
    Concerns about global warming policies that might eventually lead to the inception of a CO2 tax which will impair investments in coal-fired power plants, and coupled with attractive operating economics recently experienced in the production of electricity with the use of Nuclear Power, Public sentiment is slowly being led towards acceptance of Nuclear Power as a viable element of the energy production mix.

    In the past 15 years, nuclear power plants have shown tremendous operational improvements and many have been up-rated to add generating capacity. Average capacity factors have increased from 66 percent in 1990 to about 90 percent in 2005, owing primarily to increased availability as refueling outages have been shortened from an average of 104 days to 38 days and to improved maintenance programs that have reduced forced outages.
    Although existing nuclear plants have demonstrated high reliability and very low operating costs, the next generation of nuclear plants will almost certainly have higher capital costs than conventional fossil fuel units. However, interests in diversifying the fuel mix and the fact that nuclear power does not emit any CO2have led to 10 proposals for new nuclear units, reflecting serious interest in reviving this technology as a base-load option.

    Some of the project sponsors have already filed for Early Site Permits, and are expected to file for combined construction and operating licenses within the next few years, which could lead to construction beginning on some of the plants soon. The Energy Policy Act, EPAct 2005 also encourages new nuclear facilities with a combination of loan guarantees, production tax credits, and risk protections for initial project developers. The time horizon for new nuclear investments is such that these investments are not likely to contribute to upward rate pressures for the foreseeable future. However, utilities that are planning these units will incur some outlays, and future investments in the construction phase of their projects which are likely to be substantial in both size and risk.

    For many years, nuclear energy, while arguably a non-CO2emitting energy source, has been judged to be unacceptable for reasons of safety, unstable regulatory climate, a lack of a waste disposal solution and, more recently, economics. In recent years, however, the nuclear industry has made a remarkable turnaround. While a number of older plants have been shut down for largely economic reasons, the 104 operating nuclear plants’ performance has increased to the point, that as an overall fleet, its capacity factor was 91% in 2005. This means that these plants were operating full power for over 91% of the year. This improvement in the last 15 years is essentially the same as building 23 new 1,000 MWE plants in that time period, based on historical performance averages. In addition, all safety statistics, as measured by the Nuclear Regulatory Commission, have shown dramatic improvements as well. The Three Mile Island accident occurred over 30 years ago. The image of nuclear energy as an unsafe technology still persists. Yet the record is quite the opposite.

    The utilities have not put in an application for a nuclear power plant since the mid 1970’s. The reason for the lack of new orders was the high capital cost. When operating in a difficult regulatory environment, utility executives simply avoided new nuclear construction and went to the cheapest and fastest way to make on-line generation available, which was natural gas. Combined cycle gas plants were the generation source of choice for many years for those companies that needed to build plants.

    Today, utility executives still do not have new nuclear plant construction in their future plans even though the regulatory regime has stabilized. Although the regulatory environment has stabilized the utility companies and still uncertain how the passive systems mandated by the Nuclear Regulatory Commission can be successfully implemented, within the budgetary constraints of competition with gas-fired electrical generation plants.
    Nuclear plants are performing extremely well. Safety issues have been addressed with no new issues emerging and slow progress is being made to finally dispose of spent fuel at Yucca Mountain. What has happened is a consolidation of the utility and nuclear industry with some larger utilities purchasing existing nuclear plants from companies that do not want to be in the business.
    To address the inevitable problem of replacing existing nuclear generation, utilities have chosen to re-license existing plants from the current 40 years to 60 years. Several nuclear plants have applied and received Nuclear Regulatory Commission approval to do so. These extensions will allow utilities to continue to use these plants as long as they are economic and continue to be safely operated. Unfortunately, we still don’t see anybody ready to build a new nuclear plant. The reason is there is no new nuclear plant on the market that can compete with natural gas.

    This need for a new approach, in the construction of Nuclear Power Plants is the basis for the formation of Nuclear Technologies, Inc. to look into the production of a Prototype PEBBLE BED MODULAR REACTOR (PBMR).

    The major challenge faced by the Nuclear Industry for the reintroduction of nuclear energy into the world energy mix, is the development of a nuclear power system that:
    1. Does not include water as a coolant or a moderator.
    2. Is competitive with other energy alternatives, such as natural gas. oil or coal.
    3. A Nuclear Reactor system which can successfully go through a LOCA (Loss of Coolant accident)
    4. Can address the issue of containment
    5. Can address the issue of Terrorism
    6. Has to address the issue of proliferation
    7. Can address the issues of nuclear Waste
    As the power of the Global Warming Lobby increases the pressure on politicians, including the President of the U.S., increasesfor the U.S. to sign the Kyoto Treaty. If the U.S. signs on to the Treaty, we will see the adoption of a CO2 emission tax as an associated penalty in the use of power generation facilities which produce carbon dioxide as a by-product of combustion of fossil fuels. The environmental imperative of nuclear energy is obvious. No greenhouse gases emitted, small amounts of fuel required and small quantities of waste to be disposed of.

    Unfortunately, historically the capital costs of new nuclear plants is quite large relative to the fossil alternatives. Despite the fact that nuclear energy’s operating costs in terms of operations and maintenance and, most importantly, fuel are much lower than fossil alternatives, the barrier of high initial investment is a significant one for utilities around the world. The associated regulatory risk makes the construction of a water cooled nuclear power plant a very distant possibility.

    In order to deal with this challenge, the Senior Engineer of The Company, started the redevelopment of a technology that was originally invented, tested and prototyped in Germany in the 1970’s and 80’s. A pebble bed research and demonstration reactor operated at the Juelich Research Institute, in Germany, for over 22 years, demonstrating the soundness of the technology.
    This Pebble Bed Modular Reactor technology is the central theme of this document because it is the technology which we at The Company have been working on for so long. Unfortunately, Germany has abandoned its nuclear program for all practical purposes but there is now a world wide resurgence of interest in the development of this technology. The Chinese, the South Africans, the group at M.I.T. and the Engineering group of The Company have been researching and testing this technology for many years.

    The nuclear energy plant which we are developing is a modular, 110 Megawatt-electric (Mwe), high temperature, pebble bed reactor, using helium gas as a coolant and conversion fluid and gas turbine technology. The fundamental concept of the reactor is that it takes advantage of the high temperature and high pressure properties of the Brayton Cycle, using helium as a coolant. Use of the Brayton cycle in the production of electricity permit theoretical thermal efficiencies close to 50%.

    The PBMR utilizes an online refueling system that can yield capacity factors in the range of 95% because it does not have to be shut down to re-fuel. The pebble which form the fuel elements are constantly being re-circulated. Its modularity design concepts, in which all the systems and sub-systems of the plant can fit on specially designed railroad cars and flatbed truck and can be shipped from the factory, allows for a 3 to 5 year construction period, with expansion capabilities to meet merchant plant or large utility demand projections.
    Economic projections for the plant in South Africa indicate capital costs of between $1,000 to $ 1,300 per kilowatt. Staffing levels for an 1100 MWe, 10 unit module are about 85, and fuel costs about 0.5 cents/kwhr. When all is combined, the total busbar cost of power ranges from 1.6 to 2 cents/kwhr. These costs are in line with the production costs of existing Nuclear power plants in the U.S. Our preliminary estimates in the US, in the state of Texas place our construction costs for the perfected prototype at approximately $1,000 per Kilowatt, in line with the projected costs of the South Africans.

    PART THREE: THE NTPBMR TECHNOLOGY

    The NTPBMR technology consists of extensions of successfully designed, built and operated, helium cooled reactors built by the Germans in the 1970’s and 1980’s. The Principal characteristics of the NTPBMR’s are;

    1. THE FUEL ELEMENT:

    TRISO COATED FUEL ELEMENTS CREATED BY NUKEM FOR THE NTPBMR PROTOTYPE PROJECT


    PROPERTIES OF TRISO COATED FUEL ELEMENTS

    • The reactor core contains approximately 360,000 uranium fueled pebbles about the size of tennis balls. Each pebble contains about 9 grams of low enriched Uranium Oxide (UO2) in 10,000 to 15,000 (depending on the design) tiny grains of sand-like micro-sphere coated particles each with its own a hard silicon carbide shell.
    • The particle fuel consists of a spherical kernel of fissile or fertile fuel material encapsulated in multiple coating layers. The multiple coating layers form a miniature, highly corrosion resistant pressure vessel and an essentially impermeable barrier to release of gaseous and metallic fission products. This capability has been demonstrated at temperatures in excess of those predicted to be achieved under worst-case accident conditions in the NTPBMR.
    • The micro-spheres are tri-coated with a porous layer of carbon, a layer of pyrolytic carbon and a layer of silicon carbide. The pyrolytic carbon layer absorbs the fission fragments and the Silicon Carbide coating retains these fission fragments and radioactive gasses within the micro-sphere. These micro-spheres are embedded in a graphite matrix material.
    • The Uranium Oxide (UO2) fuel micro-sphere has a melting temperature of approximately 2800oC while the ceramic coating does not have a melting point and begins to degrade approximately at 2100oC, and the degradation of the ceramic shell in the 50 or so hours required to empty the reactor would require temperatures in excess of 4000oC. The temperature buildup in the core of the reactor in the event of a Loss of Coolant Accident (LOCA) is not expected to exceed 1600oC

    2. The Nuclear Pressure Vessel


    PROPERTIES OF THE NUCLEAR ISLAND
    A. On-line refueling capability: A unique feature of pebble bed reactors is the online refueling capability in which the pebbles are re-circulated with checks on integrity and consumption of uranium. This system allows new fuel to be inserted during operation and used or damaged fuel to be discharged and stored on site for the life of the plant. Overall burn-up is increased through this recycling. The online refueling capability allows for the extraction of all the Nuclear fuel in the event of a LOCA. Extraction of all the fuel elements in the core in the case of a nuclear event will ensure that the fuel elements will remain intact through the nuclear event without the possibility the fuel pebbles will melt.
    B. Graphite Moderator: The moderating environment of the NTPBMR is Nuclear graphite. The Reactor Pressure Vessel (RPV) will house several hundred tons of Nuclear Graphite. The nuclear graphite has high thermal mass and will allow for passive cooling of the reactor core in the loss of coolant event.
    C. Carbon Dioxide Emergency Core Fire Suppression System (ECFSS): The ECFSS is liquefied carbon dioxide. The carbon dioxide fire suppression system will mitigate the risk of a graphite fire of the type which occurred at Windscale, in England, in the early days of the English gas-cooled Magnox program. The carbon dioxide will also act as a passive emergency core cooling system to extract heat from the core.
    D. Low Power Density: The NTPBMR has very low power density in the core. Our preliminary design is for 3MWth per cubic meter. When one compares this figure with the 30 MWth power density in water cooled reactors, we can immediately see the increase in the level of safety in the LOCA event.

    3. THE NUCLEAR HELIUM SUPPLY SYSTEM: Helium gas is used as the core coolant. Helium has a very small cross-section for neutron absorption, is inert and operating in a closed-loop, brayton cycle, single phase thermodynamic cycle which can power a turbine with high cycle efficiency.

    • A Nuclear reactor using gas as the core coolant will eliminate completely the types of problem which occurred at Three Mile Island and Chernobyl, in their water-cooled nuclear reactor.
    • The inert nature of Helium will allow the filtration system of the Nuclear Helium Gas Supply System (NHGSS) to extract nearly 100% or radioactive fission products from the coolant. The NHGSS with filtration will reduce the radioactivity level in the turbine room by three orders of magnitude over existing water-cooled reactors.
    • Advances in gas turbine technologies will allow us to use helium as the coolant. Helium is an ideal cooling agent for a nuclear reactor since it is completely inert chemically, within the temperature ranges involved in a nuclear reactor vessel it remains in a single phase and it’s neutron absorption cross-sections are quite low. and operating in a closed-loop, brayton cycle, single phase thermodynamic cycle which can power a turbine with high cycle efficiency.

    The low radioactivity level in the turbine will ensure that an insignificant amount of radiation will be added to the cooling water which will return to our thermal heat sink or cooling pond.

    3. THE NUCLEAR HELIUM SUPPLY SYSTEM: Helium gas is used as the core coolant. Helium has a very small cross-section for neutron absorption, is inert and operating in a closed-loop, brayton cycle, single phase thermodynamic cycle which can power a turbine with high cycle efficiency.

    • A Nuclear reactor using gas as the core coolant will eliminate completely the types of problem which occurred at Three Mile Island and Chernobyl, in their water-cooled nuclear reactor.
    • The inert nature of Helium will allow the filtration system of the Nuclear Helium Gas Supply System (NHGSS) to extract nearly 100% or radioactive fission products from the coolant. The NHGSS with filtration will reduce the radioactivity level in the turbine room by three orders of magnitude over existing water-cooled reactors.
    • Advances in gas turbine technologies will allow us to use helium as the coolant. Helium is an ideal cooling agent for a nuclear reactor since it is completely inert chemically, within the temperature ranges involved in a nuclear reactor vessel it remains in a single phase and it’s neutron absorption cross-sections are quite low. and operating in a closed-loop, brayton cycle, single phase thermodynamic cycle which can power a turbine with high cycle efficiency.

    The low radioactivity level in the turbine will ensure that an insignificant amount of radiation will be added to the cooling water which will return to our thermal heat sink or cooling pond.

    4. THE THERMODYNAMIC CYCLE OF THE NTPBMR

    1. Fission in the Triso-coated micro-spheres creates kinetic energy through the recoil of the Uranium atoms which are split by the absorption of thermal neutrons.
    2. The kinetic energy of recoil is transformed into thermal energy in the micro-spheres.
    3. The thermal energy of the micro-sphere diffuses throughout the pebble and is transferred to the helium coolant by convective heat transfer.
    4. The high pressure and high temperature helium is directed into the high pressure turbine. The high pressure turbine operates the compressors for the return of the helium to the reactor pressure vessel.
    5. The helium is then directed to the low pressure turbine which operates the generator.
    6. The helium is then cooled through a heat exchanger and the residual heat is exhausted to the atmosphere through an air powered radiator very much like an air conditioning unit on a house.
    7. The cooled and compressed helium then re-enters the reactor pressure vessel
    Compressor