The aim of the paper was to determine the influence of the fertilization level on the energy and economics efficiency of the production technologies of selected crops processed into bioethanol or biogas. There were investigated the following crops: rye, triticale, wheat, sugar beets, maize, sorghum, reed canarygrass and Virginia fanpetals. In t
...he energetic efficiency the Energy Return on Energy Investment index (EroEI) was used. Apart from the ERoEI ratio, the Net Energy Value (NEV) ratio was also used. In the economics efficiency attitude, the Gross Margin (GM) was determined.The investigations proved that in general, the production technologies of crops where the lowest levels of nitrogen fertilization were applied proved to have the highest energetic efficiency. The highest economic efficiency was characterized by the production of corn for biogas. In the case of the production of bioethanol (all plants), ratios were on the verge of profitability or the lack of it showed.The analysis proved that the efficiency of the technologies of production of the crops to be processed into biogas is several times higher than the energetic efficiency of the technologies of production of the crops to be processed into bioethanol.
This paper reviewed principally accepted methods applied to investment analysis. To describe every aspect of investment analysis fully would require far more space than available here, so we highlight only of few of its aspects. This study collects several well-known bibliographies, contrasts them with each other and provides explanations for h
...aving done so. There are many questions about which authors and companies agree, including about how to apply certain methods, but on others there is disagreement. Four dynamic methods (Net Present Value, Internal Rate of Return, Profitability Index, and Discounted Payback Period) are demonstrated from the viewpoint of application. Moreover, this study clarifies several sensitive questions, such as handling income taxes, inflation and uncertainty. Other examined issues are only mentioned at the end of this paper, and we will publish on these more thoroughly at a later date.