In this thesis a possible cost effective runner change of some of the units in the hydroelectric power station Olidan is investigated. The possibility to drive a unit at the same efficiency point through a change of the turbine shaft speed and the rate of discharge is tested. Furthermore the theories behind model testing, determination of efficiency increase from model to prototype and efficiency measurements shall be discussed and analyzed with Olidan as a starting point.A predicted curve has been built on information from model tests and field measurements on the existing runners and runner data from the test of the new model. The predicted curve shows the difference in efficiency between an existing runner and a modern one. It is the difference in efficiency that is used in the calculations that are to show whether changing to a pair of new runners will be cost effective or not.

Nowadays naval units are participating in international missions, where new and in many cases tougher conditions will affect their propulsion. This essay deals with some of the now developed nanostructure coatings and gives a presentation of how the coatings could function on some exposed parts of the naval powertrain. The essay investigates the possibility that the coatings can be used as a protective layer that will reduce or prevent wear on selected parts of the naval powertrains. As a basis for the essay, nanotechnology is described, as well as different reasons that wear occurs and application techniques for coatings The conclusion is that nanostructured coatings can be applied and provide a much better result on hardness and wear resistance as of naval powertrains compared to micro-structural coatings, both for manufacturing and renovation. The essay presents a few examples of the military utility of the nanostructure coatings as well as suggestions for further research..

There have been changes in Earth?s climate system on both global and regional scale since the pre-industrial era and some of these changes are due to human activities such as the combustion of fossil fuels. This calls for the development of engines with a higher efficiency and less harmful emissions. One interesting concept is the Homogeneous Charge Compression Ignition (HCCI) engine, which has the advantages of potentially low emissions combined with high efficiency. However, HCCI with diesel fuel requires a relatively long fuel/air mixing time to ensure a "homogenous" charge.

In this thesis a method for evaluating investments in small scale hydro power is presented. An analysis of the future position that small scale hydro production will have on the Nordic electricity market is also carried out. This is done by an inventory of technology and economic and environmental aspects. The inventory is also a guide as to how the project should be implemented.Hydrolyzer is the name of the Excel tool developed to evaluate investments. The tool requests input data from the user and then evaluates the investment and generates a sensitivity analysis.