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This paper examines the relationship between energy and economic growth in the case of Sweden.  It analyzes the role energy plays in the level of economic activity. The prevailing economic theories focus more on other factors as important for the economic growth. The included statistical data shows that the total energy use in Sweden has declined in the last couple of years. This is mainly as a result of the shift in energy use to higher quality fuels, electricity, optimized production process and machinery, and increased use of renewable energy sources. This paper investigates the connection between total energy use and levels of economic activity in Sweden. Furthermore, it discusses Sweden’s energy policy activities and their economic and environmental implications. Instead of looking at the entire economy, as some earlier papers, the focus is placed on the industrial and service sectors. This gives the possibility to better analyze the implemented energy policies, showing their effectiveness at these sectors. Time series analysis is employed following a four step procedure. First it is the Augmented Dickey-Fuller test performed, followed by the Johansen test and the Vector Error Correction Model (VECM). The results from VECM are interpreted with the help of the Wald test. The results from this four step procedure showed univariate cointegration between Industry`s output and energy consumption and bivariate cointegration between Service`s output and energy consumption. The paper further shows that there is a relation between the types of energy used in the economic sectors and the sectors` productivity levels. This paper also aims to demonstrate the environmental and economic effects from such relation.

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<p>A method of exhaust heat recovery from a spark-ignition internal combustion engine was explored, utilizing a steam reforming thermochemical reactor to produce a hydrogen-rich effluent, which was then consumed in the engine. The effects of hydrogen in the combustion process have been studied extensively, and it has been shown that an extension of the lean stability limit is possible through hydrogen enrichment. The system efficiency and the extension of the operational range of an internal combustion engine were explored through the use of a methane fueled naturally aspirated single cylinder engine co-fueled with syngas produced with an on board methane steam reformer. It was demonstrated that an extension of the lean stability limit is possible using this system.

As energy security and climate issues are emerging as global concerns, it is commonly agreed that a transition from a conventional centralized energy system, which is largely based on combustion of fossil fuel, to a more sustainable decentralized energy system that includes mainly renewable energy sources is necessary and urgent. Due to the highly variable geographical qualities of renewable energy sources, spatial energy planning is becoming essential. This study aims to address the challenges in linking spatial modelling with assessment of regional energy consumption and renewable energy supply potential. A novel approach for exploring the feasibility of achieving energy self-sufficiency through matching energy deficit areas with energy surplus areas is proposed. A method for energy deficit and surplus area matching is developed and implemented in a VBA- based tool that serves as a decision-support tool by exploring possible future deployment of renewable energy in decentralized ways. Achieving Ontario residential electricity self-sufficiency through solar PV energy on an annual basis is explored as a case study. The results show that it is technically feasible for Ontario to be residential electricity self-sufficient through the development of solar PV energy with energy deficit areas within the region getting energy supply from nearby energy surplus areas. The case study implies that regional residential electricity self- sufficiency is achievable and it is useful for planners and policy makers to bear the regional energy deficit-surplus matching idea in mind when making urban and energy plans.

<p> Electricity is an indispensable commodity to modern society, yet it is delivered via a grid architecture that remains largely unchanged over the past century. A host of factors are conspiring to topple this dated yet venerated design: developments in renewable electricity generation technology, policies to reduce greenhouse gas emissions, and advances in information technology for managing energy systems. Modern electric grids are emerging as complex distributed systems in which a portfolio of power generation resources, often incorporating fluctuating renewable resources such as wind and solar, must be managed dynamically to meet uncontrolled, time-varying demand. Uncertainty in both supply and demand makes control of modern electric grids fundamentally more challenging, and growing portfolios of renewables exacerbate the challenge. </p><p> We study three electricity grids: the state of California, the province of Ontario, and the country of Germany. To understand the effects of increasing renewables, we develop a methodology to scale renewables penetration. Analyzing these grids yields key insights about rigid limits to renewables penetration and their implications in meeting long-term emissions targets. We argue that to achieve deep penetration of renewables, the operational model of the grid must be inverted, changing the paradigm from load-following supplies to supply-following loads. </p><p> To alleviate the challenge of supply-demand matching on deeply renewable grids, we first examine well-known techniques, including altering management of existing supply resources, employing utility-scale energy storage, targeting energy efficiency improvements, and exercising basic demand-side management. Then, we create several instantiations of supply-following loads -- including refrigerators, heating and cooling systems, and laptop computers -- by employing a combination of sensor networks, advanced control techniques, and enhanced energy storage. We examine the capacity of each load for supply-following and study the behaviors of populations of these loads, assessing their potential at various levels of deployment throughout the California electricity grid. Using combinations of supply-following strategies, we can reduce peak natural gas generation by 19% on a model of the California grid with 60% renewables. We then assess remaining variability on this deeply renewable grid incorporating supply-following loads, characterizing additional capabilities needed to ensure supply-demand matching in future sustainable electricity grids.</p>

Nowadays, energy is becoming more and more important. With the development of society, the demand of energy is also increasing correspondingly. There is 22% of the total energy which is used in building part. A more effective and sustainable energy system becomes necessary due to increasing energy prices and demand. The aim of this thesis is to make an energy survey of this building, evaluating different sources of energy supply and losses in this building. By evaluating, a better thermal comfort is expectedly achieved when having examinations, and a possible saving method is also expected in order to reduce the cost of this system.  In this project, the building is located in University of Gävle which is surveyed. It has 2 floors. The first floor is underground as a basement. An examination room is included in the second floor. There are a space heating system and heating recovery system ventilation in this examination building. At first step of analysis, the data of construction, ventilation, district heating and hot tap water were arranged by Mr. Magnus. Secondly, an energy balance had been done, and it helped to make energy input and output more clearly. In energy supply part, the solar radiation is 22.4MWh, the internal heat from people is 1.95MWh, the internal heat from equipment is 5.63MWh and district heating is 184MWh. In energy losses part, the transmission loss is 165MWh, the mechanical ventilation loss is 38.3MWh, the infiltration loss is 8.38MWh and the hot tap water is 2.09MWh. Thirdly, results of calculations were analyzed. At last, the optimization methods were given to save energy. The optimization methods were changing type of windows and improving indoor temperature which influenced the transmission loss part. Another method was reducing operating time of the ventilation system. Through these optimizing methods, the total energy use is reduced from 214MWh to 179MWh, and district heating is reduced from 184MWh to 149MWh. District heating of this building is supplied by Gävle Energi company, which is able to save 20% cost by these optimizing methods. According to the investment analysis, 19thousand SEK energy is saved per annum.

Thesis (Ph.D.)-- University of Wisconsin--Madison, 2008. / Includes bibliographical references (p. 138-144). Also available on the Internet.

Thesis (PhD)--Macquarie University, Centre for Environmental and Urban Studies, 1989. / Bibliography: leaves 360-379.

Thesis (Ph.D.)--The Pardee RAND Graduate School, 2008. / Includes bibliographical references.