Tmetoceratidae (Ammonitina) fauna from the Gerecse Mts (Hungary)

Abstract Taxonomic and stratigraphic problems of the family Tmetoceratidae and the genera Dumortieria, Catulloceras, Cotteswoldia, Pleydellia and Tmetoceras included in it are briefly discussed. Fifteen species of Tmetoceratidae are described and illustrated from the Upper Toarcian-Aalenian ammonite assemblages of the Gerecse Mts (NE Transdanubian Range, Hungary). The fauna described here is closely allied to the Mediterranean Province of the Mediterranean-Caucasian Realm

Life cycle assessment of a biomass gasification combined-cycle power system

The potential environmental benefits from biomass power are numerous. However, biomass power may also have some negative effects on the environment. Although the environmental benefits and drawbacks of biomass power have been debated for some time, the total significance has not been assessed. This study serves to answer some of the questions most often raised in regard to biomass power: What are the net CO{sub 2} emissions? What is the energy balance of the integrated system? Which substances are emitted at the highest rates? What parts of the system are responsible for these emissions? To provide answers to these questions, a life cycle assessment (LCA) of a hypothetical biomass power plant located in the Midwest United States was performed. LCA is an analytical tool for quantifying the emissions, resource consumption, and energy use, collectively known as environmental stressors, that are associated with converting a raw material to a final product. Performed in conjunction with a t echnoeconomic feasibility study, the total economic and environmental benefits and drawbacks of a process can be quantified. This study complements a technoeconomic analysis of the same process, reported in Craig and Mann (1996) and updated here. The process studied is based on the concept of power Generation in a biomass integrated gasification combined cycle (BIGCC) plant. Broadly speaking, the overall system consists of biomass production, its transportation to the power plant, electricity generation, and any upstream processes required for system operation. The biomass is assumed to be supplied to the plant as wood chips from a biomass plantation, which would produce energy crops in a manner similar to the way food and fiber crops are produced today. Transportation of the biomass and other materials is by both rail and truck. The IGCC plant is sized at 113 MW, and integrates an indirectly-heated gasifier with an industrial gas turbine and steam cycle. 63 refs., 34 figs., 32 tabs

A Review of the application of lifecycle analysis to renewable energy systems

The lifecycle concept is a "cradle to grave" approach to thinking about products, processes, and services, recognizing that all stages have environmental and economic impacts. Any rigorous and meaningful comparison of energy supply options must be done using a lifecycle analysis approach. It has been applied to an increasing number of conventional and renewable energy generation systems and in an increasing range of countries. There is now a good amount of research reporting the lifecycle environmental and economic aspects of power generation systems. This article reviews the existing lifecycle analyses of renewable energy systems to determine the current understanding of their full lifecycle impacts. These are then compared with each other and those of conventional power generation systems. The renewable energy systems reviewed include wind, solar photovoltaic, solar thermal (for electricity), hydroelectric, solid biomass, wave, geothermal, biogas, and tidal. The article also highlights the areas where more lifecycle analysis is needed