13 resultados para Planets -- Atmospheres
em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland
Resumo:
Turvatekniikan keskuksella (TUKES) on valvottavanaan noin 1 000 teollisuuslaitosta, joissa on räjähdysvaarallisia tiloja. Olosuhdedirektiivin (1999/92/EY) mukainen kansal-linen asetus (VNa 576/2003) tuli voimaan 1.9.2003. Asetus koskee uusia räjähdysvaa-rallisia tiloja välittömästi, kun taas käytössä olevat tilat on saatettava sen mukaisiksi 30.6.2006 mennessä. Asetus edellyttää, että työnantaja laatii räjähdysvaarallisille tiloille räjähdyssuojausasiakirjan ja arvioi kirjallisesti näissä tiloissa käytettävien, ilman Ex-merkkiä olevien työvälineiden riskin. Räjähdyssuojausasiakirjan ja kirjallisena tehdyn riskin arvioinnin eräs keskeinen tarkoitus on varmistaa mahdollisten syttymislähteiden laaja-alainen hallinta ja pienentää onnettomuusriskiä. Tässä diplomityössä selvitetään, mitä riskin arvioinnin täytyy sisältää ja etsitään tehokas menetelmä arvioinnin tekoon. Kolmelta yritykseltä saatiin tutkittavaksi niiden alalle tyypillinen muu kuin sähkölaite, jota käytetään räjähdysvaarallisessa tilassa. Laitteiden tuli olla Ex-merkittömiä ja olla ollut käytössä ennen asetuksen voimaan tuloa. Laitteiden ja niiden dokumenttien tutkimisella testattiin eri menetelmien soveltuvuutta riskin arviointiin. Samalla selvitettiin jo käytössä olevien laitteiden turvallisuustaso. Jokaisen pilottitapauksen kohdalla on arvioinnissa menetelty eri tavoin. Työssä esitellään keskeisimmät menetelmät, joilla riskin arviointi voidaan tehdä. Suosi-tuksena esitellään ratkaisumalli, jonka avulla voidaan päätellä laitteen tarvitsema riskinarviointimenetelmä. Pilottitapauksia arvioitiin laitteiden sijoituksen ja lukumäärän pohjalta. Suosituksena on, että riskin arvioinnissa lähdetään liikkeelle itse laitteesta ja sen soveltuvuudesta räjähdysvaaralliseen tilaan. Tällä tavalla pystytään kohdistamaan käytössä olevat resurssit paremmin niihin laitteisiin, jotka vaativat tarkemman riskin arvioinnin. Pilottitapausten perusteella räjähdysvaaralliseen tilaan tarkoitetut laitteet soveltuivat käytettäväksi tarkoitetussa käytössään. Räjähdyssuojausasiakirjaa varten on dokumentoitava tiedot niiden käytöstä, mahdollisista syttymislähteistä ja suojaavista toimenpiteistä.
Resumo:
Master’s Thesis concentrates to means and challenges in international operations for a Finnish mobile application provider Small Planet Oy during its various company stages from founding till maturing and during macro economical phases between year 1998 and 2008. Small Planet has just celebrated its 10 year anniversary and is therefore quite an extraordinary company which has survived all the highs and lows during past ten years and which has operated in the market as long as the whole mobile application industry has existed. Master’s Thesis describes possibilities for a company’s internationalization with different entry modes like exporting, licensing, investment entry and co-operative operations which are suitable for a mobile application provider. Unsuitable entry modes like franchising or contract manufacturing are not explained. The goal has been to analyze Small Planet’s international operations and to make conclusions from the practical experiences. Analysis and conclusions shall help Small Planet in its international operations in the future and should give insight to other mobile application companies and their managers who are in the situation of planning their own international operations. Results show that the best ways for Small Planet to internationalize its operations has been the co-operation with a big domestic client and the co-operation with Finnish operator infrastructure providers which have complementary products with Small Planet. Through these co-operations Small Planet has got lot of new international clients. Same time financial risks and investment need for international operations have been low. Co-operative international sales can be the most efficient international entry mode for a mobile application provider.
Kansallisten immateriaalioikeuksien vaikutus lääkekeksintöihin Suomessa ja Ruotsissa 1980-90-luvulla
Resumo:
Pro gradu- tutkielman tarkoituksena oli tutkia lääkkeiden immateriaalioikeudellisia suojamuotoja Suomen ja Ruotsin osalta. Tutkimuksessa pyrittiin selvittämään lääkkeiden kansallisen patenttisuojan, lisäsuojatodistuksen ja dokumentaatiosuojan vaikutusta lääkekeksintöihin 1980–90-luvun Suomessa ja Ruotsissa. Lääkkeiden lisäsuojatodistuksella tarkoitetaan ainoastaan lääkeaineille tarkoitettua erillistä immateriaalioikeudellista lisäsuojamuotoa, joka pidentää suoja-aikaa enimmillään viidellä vuodella. Dokumentaatiosuojalla tarkoitetaan suojamuotoa, joka suojaa lääkkeiden kehittämisessä aikaan saatuja tutkimus- ja turvallisuustuloksia rinnakkaisvalmistajilta tietyn määritellyn ajan. Suomen ja Ruotsin kansallisessa lainsäädännössä oli tarkasteluajanjaksolla olennaisia eroja. Rinnakkaisongelmana tutkittiin innovaatio- ja patenttipolitiikan merkitystä lääkekeksintöjen määrään ja laatuun. Tutkimuskysymyksiä lähestyttiin virallislähteiden ja kirjallisuuden lisäksi myös teemahaastatteluin. Haastateltavat olivat alan asiantuntijoita. Tutkimus oli haasteellinen. Oli palkitsevaa saada asiaa koskeva ”hiljainen tieto” kansiin. Suomen ja Ruotsin poliittinen ja lainsäädännöllinen ilmapiiri poikkesivat toisistaan. Suomessa vallitsi protektionistinen ilmapiiri ja se näkyi politiikassa ja vaikutti lainsäädäntöön. Menetelmäpatentista ei haluttu luopua. Menetelmäpatentti on patentti, joka käsittää ainoastaan lääkeaineen valmistusmenetelmän, eikä lopputuotetta. Suomessa sallittiin lääkeaineiden tuotepatentti vasta 1995. Toisin oli Ruotsissa; siellä poliittinen ilmapiiri ja valtion sekä lääketeollisuuden näkemykset johtivat kehitystä niin, että tuotepatenttikielto poistettiin huomattavasti aiemmin kuin Suomessa. Ruotsi oli kaukonäköisempi myös muiden suojamuotojen kohdalla. Lopputuloksena tästä seurasi se, että Ruotsin lääketeollisuus on menestynyt huomattavasti paremmin kuin Suomen. Lääkekeksintöjä tehtiin enemmän. Ruotsin lääkekeksinnöistä suuri osa oli uusia molekyylejä; Suomen vastaava osuus oli selvästi pienempi. Myös Ruotsin lääkevienti oli ja on huomattavasti suurempaa kuin Suomen.
Resumo:
Tässä työssä selvitettiin, millä tavoin räjähdysvaarallisten työtilojen työturvallisuuteen voidaan vaikuttaa ja miten turvallisuutta pidetään yllä. Työssä selvitettiin, mitä vaatimuksia räjähdysvaaralliset tilat asettavat laite- ja työturvallisuudelle. Työn lähtökohdaksi otettiin ilmanvaihdon vaikutus sisäilman olosuhteisiin ja samalla selvitettiin, mitä muutoksia räjähdysvaarallisten aineiden käyttö teollisuuden tuotantoprosesseissa aiheuttaa ilmanvaihdossa. Räjähdysvaarallisten tilojen suunnittelua ohjailevat säädökset, lait ja direktiivit. Johdonmukaisen suunnittelulla ja säädöksiä noudattamalla pystytään toteuttamaan turvallinen työympäristö. Räjähdysvaarallista tilaa päästiin tarkastelemaan Talvivaaran Kaivososakeyhtiö Oyj:n metallien talteenottolaitoksella. Työssä haluttiin tutkia rakennuksen työturvallisuutta ja työskentelyolosuhteita. Tutkimuskohteena olleessa reaktorihallissa tehtiin ilmanvaihdon suorituskyvyn mittauksia. Tarkoituksena oli myös tehdä rikkivedyn pitoisuus mittauksia, mutta Talvivaaran tuotannon viivästyessä, pitoisuus mittaukset jätettiin tämän diplomityön ulkopuolelle. Talvivaaraan reaktorirakennuksen olosuhteita ja turvallisuutta tarkasteltiin lähemmin teoreettisten laskelmien avulla. Laskelmien ja mittaustulosten perusteella reaktorirakennuksen ilmanvaihdon suorituskyky todettiin riittäväksi ja toiminta työturvalliseksi. Riskin arvioinnin perusteella reaktorirakennuksen riskitason katsotaan olevan siedettävä.
Resumo:
One of the main industries which form the basis of Russian Economical structure is oil and gas. This industry is also playing a significant role for CIS countries. Oil and gas industry is developing intensively attracting foreign investments. This situation is providing sustainable development of machinery production for hazardous areas. Operating in oil and gas areas is always related with occurrence of explosion gas atmospheres. Machines for hazardous areas must be furnished with additional protection of different types. Explosion protection is regulated with standards according to which equipment must be manufactured. In Russia and CIS countries explosion-proof equipment must be constructed in compliance with GOST standards. To confirm that equipment is manufactured according to standards’ requirements and is safe and reliable it must undergo the approval procedure. Certification in Russia is governed by Federal Laws and legislation. Each CIS country has its own approval certificates and permissions for operating in hazardous areas.
Resumo:
Statistical analyses of measurements that can be described by statistical models are of essence in astronomy and in scientific inquiry in general. The sensitivity of such analyses, modelling approaches, and the consequent predictions, is sometimes highly dependent on the exact techniques applied, and improvements therein can result in significantly better understanding of the observed system of interest. Particularly, optimising the sensitivity of statistical techniques in detecting the faint signatures of low-mass planets orbiting the nearby stars is, together with improvements in instrumentation, essential in estimating the properties of the population of such planets, and in the race to detect Earth-analogs, i.e. planets that could support liquid water and, perhaps, life on their surfaces. We review the developments in Bayesian statistical techniques applicable to detections planets orbiting nearby stars and astronomical data analysis problems in general. We also discuss these techniques and demonstrate their usefulness by using various examples and detailed descriptions of the respective mathematics involved. We demonstrate the practical aspects of Bayesian statistical techniques by describing several algorithms and numerical techniques, as well as theoretical constructions, in the estimation of model parameters and in hypothesis testing. We also apply these algorithms to Doppler measurements of nearby stars to show how they can be used in practice to obtain as much information from the noisy data as possible. Bayesian statistical techniques are powerful tools in analysing and interpreting noisy data and should be preferred in practice whenever computational limitations are not too restrictive.
Resumo:
The development of carbon capture and storage (CCS) has raised interest towards novel fluidised bed (FB) energy applications. In these applications, limestone can be utilized for S02 and/or CO2 capture. The conditions in the new applications differ from the traditional atmospheric and pressurised circulating fluidised bed (CFB) combustion conditions in which the limestone is successfully used for SO2 capture. In this work, a detailed physical single particle model with a description of the mass and energy transfer inside the particle for limestone was developed. The novelty of this model was to take into account the simultaneous reactions, changing conditions, and the effect of advection. Especially, the capability to study the cyclic behaviour of limestone on both sides of the calcination-carbonation equilibrium curve is important in the novel conditions. The significances of including advection or assuming diffusion control were studied in calcination. Especially, the effect of advection in calcination reaction in the novel combustion atmosphere was shown. The model was tested against experimental data; sulphur capture was studied in a laboratory reactor in different fluidised bed conditions. Different Conversion levels and sulphation patterns were examined in different atmospheres for one limestone type. The Conversion curves were well predicted with the model, and the mechanisms leading to the Conversion patterns were explained with the model simulations. In this work, it was also evaluated whether the transient environment has an effect on the limestone behaviour compared to the averaged conditions and in which conditions the effect is the largest. The difference between the averaged and transient conditions was notable only in the conditions which were close to the calcination-carbonation equilibrium curve. The results of this study suggest that the development of a simplified particle model requires a proper understanding of physical and chemical processes taking place in the particle during the reactions. The results of the study will be required when analysing complex limestone reaction phenomena or when developing the description of limestone behaviour in comprehensive 3D process models. In order to transfer the experimental observations to furnace conditions, the relevant mechanisms that take place need to be understood before the important ones can be selected for 3D process model. This study revealed the sulphur capture behaviour under transient oxy-fuel conditions, which is important when the oxy-fuel CFB process and process model are developed.
Resumo:
Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014
Resumo:
Viktens inverkan på jaktflygplan har alltid varit av central betydelse både när det gäller de-sign och användning. I Finska Flygvapnet är flygviktens inverkan på jaktflygplanet något som blir alltmer aktuellt nu när lufttankning används i ökad takt. Lufttankning påverkar flyg-planets totala massa betydligt, vilket i sin tur påverkar flygplanets aerodynamiska egenskap-er. De teoretiska grunderna bakom dessa förändringar i flygvikten studeras i detta kandidat-arbete. Detta görs med huvudfrågeställningen: - Hur påverkar den förändrade flygvikten jakt-flygplanet? För att besvara denna fråga används kvalitativ undersökning som baseras på litteraturstudie. Facklitteraturen som används är främst inriktad på aerodynamik. Då vissa frågor inom aero-dynamik kan anses som omtvistade, är det viktigt med en stor mängd källor. I undersökning-en jämförs därför också påståenden från olika källor och för att säkerställa trovärdigheten hos centrala påståenden och slutsatser används flera källor från olika författare. I rapporten konstateras att förändringar i jaktflygplanets totala massa har inverkan på många olika egenskaper. En hög massa leder till framförallt ökad stallhastighet, ökat inducerat mot-stånd och ökad rörelse-energi. Detta märks i praktiken på många olika sätt, vilket undersöks noggrannare i rapporten. Sammanfattningsvis leder det till försämrad förmåga att manövrera mot andra jaktflygplan, genom försämrad förmåga att stiga, accelerera och flyga snabbt. Även marginalerna vid start och landning minskar, vilket har att göra med både stallhastig-heten och rörelse-energin. Dessa marginaler påverkar utöver stridsförmågan också flygsäker-heten. Den ökade mängden bränsle har dock fördelar, exempelvis den ökade räckvidden samt möjligheten att använda efterbrännkammare i större utsträckning. Det är förstås lockande att dra slutsatsen att ett lätt flygplan har övertag över ett dito tungt flygplan, vilket rent aerodynamiskt ofta är korrekt. Men när det gäller aerodynamikens in-verkan på stridsförmågan hos ett jaktflygplan är det viktigt att se till helheten. Jaktflygplan verkar i en komplex miljö där aerodynamiken bara är en faktor av många. Detta förminskar dock inte aerodynamikens betydelse, men det är bra att ha i åtanke. I detta arbete sker ingen djupare diskussion kring dessa förhållanden, istället har fokus lagts på att förstå och förklara de olika teoretiska aspekterna ur ett krigstekniskt/aerodynamiskt perspektiv.
Resumo:
The decreasing fossil fuel resources combined with an increasing world energy demand has raised an interest in renewable energy sources. The alternatives can be solar, wind and geothermal energies, but only biomass can be a substitute for the carbon–based feedstock, which is suitable for the production of transportation fuels and chemicals. However, a high oxygen content of the biomass creates challenges for the future chemical industry, forcing the development of new processes which allow a complete or selective oxygen removal without any significant carbon loss. Therefore, understanding and optimization of biomass deoxygenation processes are crucial for the future bio–based chemical industry. In this work, deoxygenation of fatty acids and their derivatives was studied over Pd/C and TiO2 supported noble metal catalysts (Pt, Pt–Re, Re and Ru) to obtain future fuel components. The 5 % Pd/C catalyst was investigated in semibatch and fixed bed reactors at 300 °C and 1.7–2 MPa of inert and hydrogen–containing atmospheres. Based on extensive kinetic studies, plausible reaction mechanisms and pathways were proposed. The influence of the unsaturation in the deoxygenation of model compounds and industrial feedstock – tall oil fatty acids – over a Pd/C catalyst was demonstrated. The optimization of the reaction conditions suppressed the formation of by–products, hence high yields and selectivities towards linear hydrocarbons and catalyst stability were achieved. Experiments in a fixed bed reactor filled with a 2 % Pd/C catalyst were performed with stearic acid as a model compound at different hydrogen–containing gas atmospheres to understand the catalyst stability under various conditions. Moreover, prolonged experiments were carried out with concentrated model compounds to reveal the catalyst deactivation. New materials were proposed for the selective deoxygenation process at lower temperatures (~200 °C) with a tunable selectivity to hydrodeoxygenation by using 4 % Pt/TiO2 or decarboxylation/decarbonylation over 4 % Ru/TiO2 catalysts. A new method for selective hydrogenation of fatty acids to fatty alcohols was demonstrated with a 4 % Re/TiO2 catalyst. A reaction pathway and mechanism for TiO2 supported metal catalysts was proposed and an optimization of the process conditions led to an increase in the formation of the desired products.
Resumo:
The Kraft pulping process is the dominant chemical pulping process in the world. Roughly 195 million metric tons of black liquor are produced annually as a by-product from the Kraft pulping process. Black liquor consists of spent cooking chemicals and dissolved organics from the wood and can contain up to 0.15 wt% nitrogen on dry solids basis. The cooking chemicals from black liquor are recovered in a chemical recovery cycle. Water is evaporated in the first stage of the chemical recovery cycle, so the black liquor has a dry solids content of 65-85% prior to combustion. During combustion of black liquor, a portion of the black liquor nitrogen is volatilized, finally forming N2 or NO. The rest of the nitrogen remains in the char as char nitrogen. During char conversion, fixed carbon is burned off leaving the pulping chemicals as smelt, and the char nitrogen forms mostly smelt nitrogen (cyanate, OCN-). Smelt exits the recovery boiler and is dissolved in water. The cyanate from smelt decomposes in the presence of water, forming NH3, which causes nitrogen emissions from the rest of the chemical recovery cycle. This thesis had two focuses: firstly, to determine how the nitrogen chemistry in the recovery boiler is affected by modification of black liquor; and secondly, to find out what causes cyanate formation during thermal conversion, and which parameters affect cyanate formation and decomposition during thermal conversion of black liquor. The fate of added biosludge nitrogen in chemical recovery was determined in Paper I. The added biosludge increased the nitrogen content of black liquor. At the pulp mill, the added biosludge did not increase the NO formation in the recovery boiler, but instead increased the amount of cyanate in green liquor. The increased cyanate caused more NH3 formation, which increased the NCG boiler’s NO emissions. Laboratory-scale experiments showed an increase in both NO and cyanate formation after biosludge addition. Black liquor can be modified, for example by addition of a solid biomass to increase the energy density of black liquor, or by separation of lignin from black liquor by precipitation. The precipitated lignin can be utilized in the production of green chemicals or as a fuel. In Papers II and III, laboratory-scale experiments were conducted to determine the impact of black liquor modification on NO and cyanate formation. Removal of lignin from black liquor reduced the nitrogen content of the black liquor. In most cases NO and cyanate formation decreased with increasing lignin removal; the exception was NO formation from lignin lean soda liquors. The addition of biomass to black liquor resulted in a higher nitrogen content fuel mixture, due to the higher nitrogen content of biomass compared to black liquor. More NO and cyanate were formed from the fuel mixtures than from pure black liquor. The increased amount of formed cyanate led to the hypothesis that black liquor is catalytically active and converts a portion of the nitrogen in the mixed fuel to cyanate. The mechanism behind cyanate formation during thermal conversion of black liquor was not clear before this thesis. Paper IV studies the cyanate formation of alkali metal loaded fuels during gasification in a CO2 atmosphere. The salts K2CO3, Na2CO3, and K2SO4 all promoted char nitrogen to cyanate conversion during gasification, while KCl and CaCO3 did not. It is now assumed that cyanate is formed when alkali metal carbonate or an active intermediate of alkali metal carbonate (e.g. -CO2K) reacts with the char nitrogen forming cyanate. By testing different fuels (bark, peat, and coal), each of which had a different form of organic nitrogen, it was concluded that the form of organic nitrogen in char also has an impact on cyanate formation. Cyanate can be formed during pyrolysis of black liquor, but at temperatures 900°C or above, the formed cyanate will decompose. Cyanate formation in gasifying conditions with different levels of CO2 in the atmosphere was also studied. Most of the char nitrogen was converted to cyanate during gasification at 800-900°C in 13-50% CO2 in N2, and only 5% of the initial fuel nitrogen was converted to NO during char conversion. The formed smelt cyanate was stable at 800°C 13% CO2, while it decomposed at 900°C 13% CO2. The cyanate decomposition was faster at higher temperatures and in oxygen-containing atmospheres than in an inert atmosphere. The presence of CO2 in oxygencontaining atmospheres slowed down the decomposition of cyanate. This work will provide new information on how modification of black liquor affects the nitrogen chemistry during thermal conversion of black liquor and what causes cyanate formation during thermal conversion of black liquor. The formation and decomposition of cyanate was studied in order to provide new data, which would be useful in modeling of nitrogen chemistry in the recovery boiler.
Resumo:
Cyanobacteria are the only prokaryotic organisms performing oxygenic photosynthesis. They comprise a diverse and versatile group of organisms in aquatic and terrestrial environments. Increasing genomic and proteomic data launches wide possibilities for their employment in various biotechnical applications. For example, cyanobacteria can use solar energy to produce H2. There are three different enzymes that are directly involved in cyanobacterial H2 metabolism: nitrogenase (nif) which produces hydrogen as a byproduct in nitrogen fixation; bidirectional hydrogenase (hox) which functions both in uptake and in production of H2; and uptake hydrogenase (hup) which recycles the H2 produced by nitrogenase back for the utilization of the cell. Cyanobacterial strains from University of Helsinki Cyanobacteria Collection (UHCC), isolated from the Baltic Sea and Finnish lakes were screened for efficient H2 producers. Screening about 400 strains revealed several promising candidates producing similar amounts of H2 (during light) as the ΔhupL mutant of Anabaena PCC 7120, which is specifically engineered to produce higher amounts of H2 by the interruption of uptake hydrogenase. The optimal environmental conditions for H2 photoproduction were significantly different between various cyanobacterial strains. All suitable strains revealed during screening were N2-fixing, filamentous and heterocystous. The top ten H2 producers were characterized for the presence and activity of the enzymes involved in H2 metabolism. They all possess the genes encoding the conventional nitrogenase (nifHDK1). However, the high H2 photoproduction rates of these strains were shown not to be directly associated with the maximum capacities of highly active nitrogenase or bidirectional hydrogenase. Most of the good producers possessed a highly active uptake hydrogenase, which has been considered as an obstacle for efficient H2 production. Among the newly revealed best H2 producing strains, Calothrix 336/3 was chosen for further, detailed characterization. Comparative analysis of the structure of the nif and hup operons encoding the nitrogenase and uptake hydrogenase enzymes respectively showed minor differences between Calothrix 336/3 and other N2-fixing model cyanobacteria. Calothrix 336/3 is a filamentous, N2-fixing cyanobacterium with ellipsoidal, terminal heterocysts. A common feature of Calothrix 336/3 is that the cells readily adhere to substrates. To make use of this feature, and to additionally improve H2 photoproduction capacity of the Calothrix 336/3 strain, an immobilization technique was applied. The effects of immobilization within thin alginate films were evaluated by examining the photoproduction of H2 of immobilized Calothrix 336/3 in comparison to model strains, the Anabaena PCC 7120 and its ΔhupL mutant. In order to achieve optimal H2 photoproduction, cells were kept under nitrogen starved conditions (Ar atmosphere) to ensure the selective function of nitrogenase in reducing protons to H2. For extended H2 photoproduction, cells require CO2 for maintenance of photosynthetic activity and recovery cycles to fix N2. Application of regular H2 production and recovery cycles, Ar or air atmospheres respectively, resulted in prolongation of H2 photoproduction in both Calothrix 336/3 and the ΔhupL mutant of Anabaena PCC 7120. However, recovery cycles, consisting of air supplemented with CO2, induced a strong C/N unbalance in the ΔhupL mutant leading to a decrease in photosynthetic activity, although total H2 yield was still higher compared to the wild-type strain. My findings provide information about the diversity of cyanobacterial H2 capacities and mechanisms and provide knowledge of the possibilities of further enhancing cyanobacterial H2 production.
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Energy scenarios are used as a tool to examine credible future states and pathways. The one who constructs a scenario defines the framework in which the possible outcomes exist. The credibility of a scenario depends on its compatibility with real world experiences, and on how well the general information of the study, methodology, and originality and processing of data are disclosed. In the thesis, selected global energy scenarios’ transparency and desirability from the society’s point of view were evaluated based on literature derived criteria. The global energy transition consists of changes to social conventions and economic development in addition to technological development. Energy solutions are economic and ethical choices due to far-reaching impacts of energy decision-making. Currently the global energy system is mostly based on fossil fuels, which is unsustainable over the long-term due to various reasons: negative climate change impacts, negative health impacts, depletion of fossil fuel reserves, resource-use conflicts with water management and food supply, loss of biodiversity, challenge to preserve ecosystems and resources for future generations, and inability of fossil fuels to provide universal access to modern energy services. Nuclear power and carbon capture and storage cannot be regarded as sustainable energy solutions due to their inherent risks and required long-term storage. The energy transition is driven by a growing energy demand, decreasing costs of renewables, modularity and scalability of renewable technologies, macroeconomic benefits of using renewables, investors’ risk awareness, renewable energy related attractive business opportunities, almost even distribution of solar and wind resources on the planet, growing awareness of the planet’s environmental status, environmental movements and tougher environmental legislation. Many of the investigated scenarios identified solar and wind power as a backbone for future energy systems. The scenarios, in which the solar and wind potentials were deployed in largest scale, met best the set out sustainability criteria. In future research, energy scenarios’ transparency can be improved by better disclosure on who has ordered the study, clarifying the funding, clearly referencing to used sources and indicating processed data, and by exploring how variations in cost assumptions and deployment of technologies influence on the outcomes of the study.