Syftet med examensarbetet är att undersöka om en småskalig variant av vattenkraftverk baserat på Arkimedes skruv kan vara lönsam för att driva elljusspår eller gatubelysning. Ett teoretiskt lösningsförslag på hur Arkimedes skruv kan fungera som vattenkraftverk togs fram via design thinking och brainstorming samt en sållningsmetod av lösningsförslag genom morfologisk matris. I denna rapport ingår även ett förslag avseende lämpliga delar till en framtida prototyp, prisförslag och årlig energiproduktion. Vattenkraftverket var tänkt att användas för att producera energi för att driva 4 km elljusspår eller 6 km gatubelysning. För att ta reda på om vattenkraftverket är ekonomiskt lönsamt jämfördes vattenkraftverket med vindkraft, där vattenkraftverket ansågs vara lönsamt ifall det kunde motsvara vindkraftverkets återbetalningstid. Arbetet resulterade i en teoretisk modell av ett fungerande småskaligt vattenkraftverk som klarar att driva upp till 4 km elljusspår eller gatubelysning upp till 6 km. Lösningsförslaget klarar däremot inte att konkurrera med ett fullskaligt vindkraftverks återbetalningstid. Däremot är inte vattenkraft i allmänhet sämre än vindkraft då Sveriges vattenkraftverk producerar nästan fyra gånger så mycket energi jämfört med Sveriges vindkraftverk. [1] / The purpose of this master thesis is to examine if a small-scale hydro power plant based on Archimedes screw could be a profitable way to power an illuminated outdoor exercise track or corresponding streetlights. A theoretical solution of how the Archimedes screw could work as a hydro power plant was decided on by using a morphological matrix as a by a screening method. Suggestions of parts for the prototype, price calculations and annual energy production of the design. The hydro screw was designed to produce energy that can supply an illuminated exercise track of 4 km or streetlights up to 6 km. To figure out if the hydro screw is economically profitable, the solution was compared to a land-based windmill, were the hydro screw was considered to be profitable if it could match a windmills payback time.  The work resulted in a theoretical design of a small-scale hydro power plant that could work for powering illuminated exercise tracks up to 4 km or streetlights up to 6 km. Results include that the solution cannot match a windmills payback time. On the other hand, hydropower is generally not worse than wind power since Sweden´s hydro powerplants produce almost four times as much energy compered to Sweden´s wind power production. [1]

Stand-alone or micro off-grid systems can be used to electrify remote areas when it is not economically justifiable to connect to the power grid. In Sweden there are several flood gates that are used to regulate the water level in hydropower dams, these dams are not always easily accessible. Furthermore, some flood gates are not electrified making the adjustment of the water level complicated and time consuming. An off-grid solution could be used to electrify the water level adjustment and this report aims to identify one remote dam, owned by the company VB Kraft, that could be electrified by implementing an off-grid solution. The report will also investigate which off-grid solution that is most applicable concerning maintenance demand, technical and economic aspects. Sensors for monitoring the status of the dam will also be identified which are required to preserve dam security. The chosen off-grid solution will be simulated on a yearly basis and the most appropriate size of the components will be specified. The report has been conducted by collecting material from the company, a literature study and by interviews and email conversations. Calculations have been performed by using MATLAB and Excel. The data is based on measurements from the Swedish Meteorological and Hydrological Institute. The result revealed that Lilla Ursen, a remote dam in Dalarnas county, is maneuvered often and therefore this study will investigate electrification of this dam. Out of the four alternatives (small wind, hydro and hydrokinetic power and PV), PV was considered the most suitable in an off-grid system combined with a lead-acid battery. Sensors considered important for dam security are water level and flow monitoring, position indicator for the flood gate, camera monitoring and a temperature sensor. It also important with a logger and transmitter. The battery is protected with a charge controller. A series of sensitivity analysis have been conducted and the result showed a large variation concerning the battery capacity and the modules area and peak power. For Lilla Ursen it is recommended with a PV module of 30 Wp and a lead-acid battery with a capacity of 280 Ah.

Syftet med studien är att bidra med kunskap om hur elever i årskurs 1–3 förståroch förklarar det fysikaliska fenomenet flyta och sjunka. Studien ämnar ävenatt utforska hur en praktisk aktivitet kan bidra till att synliggöra och skapa endjupare förståelse för begreppen Arkimedes princip och densitet för elever pålågstadiet. För att besvara studiens syfte valdes en designbaserad forskningsansats där en aktivitet designades och utfördes med 31 elever i årskurserna 1–3. Aktiviteten spelades in på video- och röstfiler som senare analyserades tematiskt.Resultaten visar att eleverna har viss kunskap om varför vissa saker flyter ochandra sjunker. Resultaten visar även att den praktiska aktiviteten bidrar till attsynliggöra begreppen Arkimedes princip och densitet på ett tydligt sätt vilketvisar att även de yngsta eleverna kan närma sig fysikens begrepp och teorier.När lärare i de lägre årskurserna låter eleverna tidigt börja närma sig och arbetamed naturvetenskapliga begrepp så läggs en bra grund inför kommande studieri de naturvetenskapliga ämnena. / The purpose of this study is to contribute with knowledge about how pupils ingrades 1-3, understands and explain the physical phenomenon of floating andsinking. The study also aims to explore how a practical activity can help tomake the physical phenomenon visible and create a deeper understanding ofthe concepts of Archimedes' principle and density for pupils in primary school.To answer the purpose of the study, a design-based research approach waschosen where an activity was created and performed with 31 pupils in grades1-3 in Sweden. The activity was recorded on video and voice files which werelater analyzed thematically.The results show that the pupils have some knowledge of why some thingsfloat and others sink. The results also show that the practical activity contributes to making the concepts of Archimedes' principle and density visible in aclearer way, which shows that even the youngest pupils can approach physicalconcepts and theories. When teachers in the lower grades allow pupils to startapproaching and working with scientific concepts at an early stage, a goodfoundation is laid for future studies in the natural science subjects.