WindFuels – Competitive Transportation Fuels From Wind Energy and Waste CO 2
It is essential for the market to help drive the dramatic cut needed in CO2 emissions to prevent a climate disaster in this century. We show that the economics for producing clean liquid hydrocarbons and alcohols from water and waste CO2 on wind farms improved by an order of magnitude between 2002 and 2008, and we present the scientific and technological basis for another factor-of-two improvement in these economics. Wind energy is by far the most competitive renewable energy resource in many regions. The perceived challenge is getting wind energy from good sites to where and when it is needed, both for the transportation sector and for the power grid. Efficient conversion of wind energy and waste CO2 into clean, stable, liquid fuels – also called WindFuels – solves these problems. Annual WindFuels production per land area in good wind regions should exceed biofuels production density in fertile farming areas by a factor of five. First, water and renewable electrical power are fed into an electrolyzer, which produces the required hydrogen. Then waste CO2 (from coal power plants) and the renewable hydrogen are piped into a novel Reverse Water Gas Shift (RWGS) process, which permits practical reduction of CO2 to the CO needed at efficiencies approaching theoretical limits. The renewable CO and H2 are then fed into a novel Renewable Fischer-Tropsch Synthesis (RFTS) process. There they are converted into mostly mid-alcohols (ethanol, propanol, and butanol) and other valuable chemicals. These fuels may then be readily stored and distributed by conventional means – pipelines and tanker trucks. The electrolyzer also produces a huge amount of oxygen, which may be sold if market conditions warrant, or it may be utilized in novel processes to improve the plant efficiency. From basic thermodynamics, one readily calculates that the theoretical maximum chemical efficiency of synthesis of ethanol from H2 and CO2 is 80.1% without utilization of the excess heat released from the Fischer Tropsch Synthesis (FTS) reactor. If this excess heat is also converted in an ideal heat engine, the theoretical combined-cycle efficiency limit is ~90%. One advantage of ethanol may be appreciated by noting that its synthesis from H2+CO2 results in 1.5 molecules of water per carbon atom in the fuel, while the synthesis of alkanes or alkenes results in 2 molecules of waste water per carbon atom in the fuel. Previously, fossil-based FTS efficiencies for environmentally attractive fuels, such as ethanol and propanol, have usually been under 40%. The need for very efficient recycling of the large amounts of H2, CO, and CO2 in the byproducts from mid-alcohols FTS has possibly been the strongest argument against mid-alcohols FTS compared to gasoline, lubricants, and diesel. A novel plant design is presented, validated by many simulations, that permits order-of-magnitude reduction in energy penalties associated with the major separations in a fully recycled mid-alcohols plant compared to previously published designs. The example wind-driven RFTS plant size chosen for illustration and simulated in detail assumes 250 MW mean input electrical power. It achieves 72% FTS-plant higher heating value (HHV) efficiency in production of mid-alcohols and other products from H2 and recovered (waste) CO2, or about 60% net HHV efficiency when including the electrolyzer at expected near-term performance. At least eight separate, substantial innovations in the system design combine to permit this major advance in RFTS efficiency and cost effectiveness. It is worth pointing out that as recycle efficiency and byproduct utilization both approach 100%, which is the primary thrust in the RFTS optimization, catalyst selectivity and activity both become much less important. Catalysts never affect the thermodynamics – only the kinetics of the various pathways. Hence, further development of catalysts will have limited effect on system efficiency in a plant with 95% recycle efficiency, though of course it will influence profitability by changing the product mix.
Systems, methods and compositions for the production of synthetic hydrocarbon compounds
1. A process for producing hydrocarbon compounds comprising at least the following steps: a) generating hydrogen gas from water and electricity; ! b) generating a mixture of at least hydrocarbon compounds, some of which are in gaseous form, the gaseous water vapor and heat to at least a carbon monoxide gas and said hydrogen gas; ! wherein before or after step b) is carried out one or more of the following further steps: c) increasing or decreasing the temperature of one or more gases at least near adiabatically, through compression / expansion of the incoming gas in the compressor / expander with / generate electric energy to / from the electric power line, so that a corresponding thermal energy is less than 10% the used / generated electric energy used for / generated by the compression / expansion; ! d) increasing or decreasing the pressure of one or more gases at least near isothermally, through compression / expansion of the incoming gas in the compressor / expander with / generate electric energy to / from the electric power line and cooling / heating the compressed / expanded gas delivery a heat / heat extraction from the supply line to the heat, so that the absolute temperature of the process gas K deviates by less than 10% of the absolute temperature K incoming gas; ! where the following steps are performed: e) increasing the temperature or pressure change, or both, since both, of said hydrogen generated at
Contractor Failure: Analysis
The possibility exists for any construction contractor to fail to filfill the contract requirements associated with a facility. Contractor failure occurs when a contractor is unable to perform his/her contractual duties, thus requiring the facility owner to invoke the contract's nonperformance clause. This paper provides aggregate contractor business failure statistics and outlines potential causes for failure. A framework to identify and quantify the associated costs is also introduced. Several case studies are presented to examine the cause and cost of failure and the means by which the facilities were completed. Alternatives available for project completion when contractor failure occurs are discussed. Recommendations to identify and monitor contractors at high risk for failure are outlined as well. This paper provides facility owners with a greater awareness of the possibility of contractor failure, how to quantify costs of contractor failure, and avoidance techniques.