Stora Enso Hylte Bruk är ett tidningspappersbruk beläget i Hyltebruk. De fyra pappersmaskinerna startades 1972(PM1), 1974(PM2), 1976(PM3) och 1989(PM4). Produktionen 2005 från dessa pappersmaskiner var 800 000 ton papper. För att tillverka papper åtgår stora mängder energi i form av värme och el, Hylte Bruk gjorde 2005 av med 1 % av Sveriges totala elenergibehov. Den 1/7 2004 höjdes processrelaterad elskatt från 0 till 0,5 öre/kWh vilket ledde fram till den lag som trädde i kraft den 1/1 2005, ”lag om program för energieffektivisering” (PFE)1. Ändamålet är att främja en effektiv energianvändning och ger energiintensiv industri möjlighet att delta i ett 5-årigt program för energieffektivisering. De företag som är kvalificerade att ingå i programmet och klarar av de krav som ställs befrias från elskatten. Som en del av det här programmet ingår att utarbeta en lista med elenergieffektiviseringar som ska överlämnas till Statens Energimyndighet. Detta examensarbete kan efter beslut av ansvariga på Hylte Bruk ingå som en del av denna lista. Syftet med examensarbetet var att undersöka effektiviteten hos tolv pumpar på PM2 genom mätning av effekt, flöde och tryck. En del av dessa har varit i drift i upp till 32 år, under denna tid har slitage skett, vissa pumpar har gått mot delvis stängda ventiler samt förutsättningarna i form av produktion har ändrats sedan de dimensionerades. För alla de berörda pumparna kan en effektivisering göras, den kan bestå av: lägre tryckhöjd, mindre flöde, pump med bättre verkningsgrad, eller en kombination av ovanstående exempel. De förslag som har en återbetalningstid kortare än tre år ger tillsammans en energibesparing på 1 375 000 kWh/år, vilket motsvarar mer än ¼ av vad pumparna förbrukar idag. Om istället alla de förslagen som är framarbetade och genomförbara skulle realiseras kan energibesparingen ökas ytterligare till 2 302 000 kWh/år, detta skulle dock innebära en större investeringskostnad vilket resulterar i en längre återbetalningstid.

A satellite launch vehicle not subjected to any perturbations, external or internal, could be guided along a trajectory by following a stored, pre-computed steering program. In practice, perturbations do occur, and in order to take account of them and to achieve an accurate injection, a closed loop guidance system is required. Guidance algorithm is developed by solving the optimal control problem. Closed form solution is difficult because the necessary conditions are in the form of Two Point Boundary Value Problems (TBVP) or Multi Point Boundary Value Problems (MPBVP). Development of non-iterative guidance algorithm is taken as a prime objective of this thesis to ensure reliable on-board implementation. If non-iterative algorithms are required, the usual practice is to approximate the system equations to derive closed form solutions. In the present work, approximations cannot be used because the algorithm has to cater to a wide variety of vehicles and missions. Present development adopts an alternate approach by splitting the reconfigurable algorithm development in to smaller sub-problems such that each sub-problem has closed form solution. The splitting is done in such a way that the solution of the sub-problems can be used as building blocks to construct the final solution. By adding or removing the building blocks, the algorithm can be configured to suit specific requirements. Chapter 1 discusses the motivation and objectives of the thesis and gives a literature survey. In chapter 2, Classical Flat Earth (CFE) guidance algorithm is discussed. The assumptions and the nature of solution are closely analyzed because CFE guidance is used as the baseline for further developments. New contribution in chapter 2 is the extension of CFE guidance for a generalized propulsion system in which liquid and solid engines are present. In chapter 3, CFE guidance is applied for a mission with large pitch steering angles. The result shows loss of optimality and performance. An algorithm based on regular perturbation is developed to compensate for the small angle approximation. The new contribution in chapter 3 is the development of Regular Perturbation based FE (RPFE) guidance as an extension of CFE guidance. RPFE guidance can be configured as CFE guidance and FEGP. Algorithms presented up to chapter 3 are developed to inject a satellite in to orbits with unspecified inertial orientation. Communication satellite missions demand injection in to an orbit with a specific inertial orientation defined by argument of perigee. This problem is formulated using Calculus of Variations in chapter 4. A non-iterative closed form solution (Predicted target Flat Earth or PFE guidance) is derived for this problem. In chapter 5, PFE guidance is extended to a multi-stage vehicle with a constraint on the impact point of spent lower stage. Since the problem is not analytically solvable, the original problem is split in to three sub-problems and solved. Chapter 6 has two parts. First part gives theoretical analysis of the sub-optimal strategies with special emphasis to guidance. Behavior of predicted terminal error and control commands in presence of plant approximations are theoretically analyzed for a class of optimal control problems and the results are presented as six theorems. Chapter 7 presents the conclusions and future works.

This thesis is an investigation of whether an energy efficiency obligation scheme would be cost-effective for the Swedish industrial sector. The basic guidelines of the scheme were constructed based on the characteristics proposed in the Energy Efficiency Directive and the previously implemented schemes in other EU Member States. In order to measure the cost effectiveness of the scheme for the industries, a Cost Benefit Analysis was performed. The results of the study show that the participation of the industries in an energy efficiency obligation scheme seems to be cost effective, and the Benefit to Cost Ratios of the analysis where ranging in numbers higher than one, showing that the benefits outweigh the costs. The scheme is in general more cost effective when scenarios assuming high policy intensity for the whole economy of the country are used as input for the calculation of the BCRs, which are also affected positively when higher fuel prices scenarios are adopted. The obligation should be placed upon the distributors, since the prices of energy distribution are administratively regulated. There is opportunity of financial benefits for the Swedish industries from agreements of energy savings delivery to the distributors in order for them to fulfill their obligation. These benefits will support the cost recovery of the investments for the energy savings measures. The possibility of certificate trading in the context of the scheme is another option that can create opportunities for financial gains and stimulate further the energy market. Basing the costs inputs from other EU Member States offers an insight on how these costs could be formed in the case of Sweden, but they cannot be taken as a complete calculation of the scheme’s financial effects. As a result, this study does not offer a final conclusion on the cost-effectiveness of the scheme; it rather serves as a means of support of the final conclusion regarding the cost-effectiveness of energy efficiency obligation schemes for the Swedish industries.