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Bearingless motor (BLM) technology offers a competitive solution to active magnetic bearings (AMBs) in high-speed applications. A bearingless drivetrain (BLDT) working as part of a kinetic compressor in a heat pump exceeding 0.5 MW and 25 000 rpm is open for questions: how should the geometry, materials, and parameters be chosen without exceeding the electromechanical and thermal limits; what rotor configuration would suit the heat pump; and how can the working fluid of the heat pump be used in the motor cooling? This paper presents the interdisciplinary design process of a BLDT as part of the compressor of a high-temperature heat pump (HTHP). The motor design process—the motor constituting the core driving the compressor of the heat pump, each interacting with the others, thus bringing about various design challenges—is summarized in a flowchart and subsequently elaborated on. Dimensioning rules for the bearingless structures are presented. Finite element analysis (FEA) is used to evaluate the surface and interior permanent magnet BLM structures under consideration. Different stack materials are considered and preliminary electromechanical optimization by a genetic algorithm is carried out. To ensure structural rigidity, FEA of electromagnetic, mechanical, thermal, and rotor dynamic performance is conducted. FEA of drive losses is carried out and cooling alternatives are considered, based on which temperature distributions and thermal stresses with the chosen cooling arrangements are calculated again with FEA. The power and performance of the structures are discussed. As a result of the analyses, a suitable hermetic motor design is chosen for the HTHP compressor drivetrain.

The fast preliminary design and safe operation of turbomachines require a simple and accurate prediction of axial thrust. An underestimation of these forces may result in undersized bearings that can easily overload and suffer damage. While large safety margins are used in bearing design to avoid overloading, this leads to costly oversizing. In this study, the accuracy of currently available axial thrust estimation methods is analyzed by comparing them to each other and to theoretical pressure distribution, numerical simulations, and new experimental data. Available methods tend to underestimate the maximum axial thrust and require data that are unavailable during the preliminary design of turbomachines. This paper presents a new, simple axial thrust estimation method that requires only a few preliminary design parameters as the input data and combines the advantages of previously published methods, resulting in a more accurate axial thrust estimation. The method is validated against previously public data from a radial pump and new experimental data from a centrifugal compressor, the latter measured at Lappeenranta-Lahti University of Technology LUT, Finland, and two gas turbines measured at Aurelia Turbines Oy, Finland. The maximum deviation between the estimated axial thrust using the hybrid method and the measured one is less than 13%, while the other methods deviate by tens of percent. Publishers version

In recent times, the use and development of small-scale ( 10 kW) ORC systems has received an increasing interest. However, the operational characteristics of small-scale high-expansion ratio ORC turbines are not yet well understood. In this study, a small-scale high-temperature ORC was investigated experimentally. The studied system has a high-speed turbogenerator including a supersonic radial turbine, a permanent magnet generator and a Barske-type feed pump assembled on a single shaft. Siloxane MDM is used as the working fluid. The turbogenerator performance was studied under different operating conditions and the experimental results were compared against the results obtained from the numerical ORC cycle model for validating the numerical results. The turbine was analyzed to have the mechanical power output close to the system design value and a maximum electric power output of 6 kW was measured. The turbogenerator was capable to be operated at the targeted rotational speed range of 12 000 rpm to 31 000 rpm. Thus, the technical potential of using high rotational speed and supersonic turbomachinery in small-scale and high expansion ratio ORC applications was confirmed. The results highlights the importance of reducing turbogenerator losses and internal power consumption to reach higher power outputs in the future. Post-print / Final draft

Heat pump technology has the capability to upgrade unusable low-temperature waste heat and make the upgraded heat usable for different types of industrial and domestic heating applications. Heat upgrading could allow to reach significant energy savings and reduced emissions when compared to other heat production methods. In this paper, upgrading waste heat into a higher temperature with large-scale centrifugal compressor driven cascade heat pumps was studied numerically. A combined method for heat pump thermodynamic analysis and compressor design analysis was developed and implemented in order to investigate the effect of different working fluid combinations and the effect of the cascade heat exchanger temperature level on the heat pump performance. Seven potential fluid candidates were included and condenser temperature of 90 °C, evaporator temperature of 20 °C, and evaporator heat rate of 1 MW were used in the analysis. It was concluded, that the implemented method can provide an efficient tool for evaluating suitable working fluids and design operating conditions for centrifugal compressor driven high temperature cascade heat pumps. The highest coefficient of performance of 3.08 was simulated by using R601 as the fluid in the low-temperature cycle and R245fa in the high-temperature cycle. These fluids also resulted in feasible compressor geometries and rotational speeds, as well as allowed to reach high compressor efficiencies of well above 80% based on the enthalpy loss models. Coefficient of performances of over 3.0 were simulated also with the fluid combinations R601/R600, R245fa/R245fa and R600/R245fa. Post-print / Final draft

Power conversion systems based on Organic Rankine Cycles have been identified as a potential technology especially in converting low-grade waste heat into electricity as well as in small-scale biomass, solar, or geothermal power plants. One of the most important steps in designing such a system is the selection of the working fluid and the optimal fluids are highly dependent on the cycle heat source and condenser cooling fluid temperature levels as well as on the power scale. In this study, the use of different types of working fluids in subcritical organic Rankine cycles is investigated thoroughly by means of thermodynamic analysis. The studied fluid groups are hydrocarbons, fluorocarbons, and siloxanes. The impacts of the specific features related to different fluid groups as well as of the relation between the critical temperature and molar mass of the fluid on the cycle design and operational parameters are investigated. As a result of the study, guidelines and recommendations are generated that can be used in the preliminary evaluation of potential fluid candidates and cycle configurations. In general, the results of the study show that the higher the critical temperature of the fluid, the higher the obtainable cycle efficiency if the evaporation pressure slightly below the critical pressure of the fluid can be obtained. On the other hand, the high critical temperature of the fluid typically leads to significantly high expansion ratios over the process expander and to low condensing pressures. The high pressure ratios are especially present when considering the use of complex siloxanes and high critical temperature hydrocarbons as the working fluids. Based on the results, the studied fluorocarbons and low critical temperature hydrocarbons were evaluated as the most suitable fluids for low-temperature applications whereas siloxanes and hydrocarbons with a high critical temperature were evaluated as the most promising fluid candidates for high-temperature ORC applications.

In recent years, the use of small-scale organic Rankine cycles (ORC) in exhaust gas heat recovery of reciprocating engines has been intensively studied. In this paper, the working fluid selection and experimental results of a small-scale ORC unit utilizing exhaust heat of a diesel engine are presented and discussed. Based on the working fluid selection study, siloxane MDM was evaluated as the most suitable fluid for the experimental system. The experiments were conducted with the aim of studying and analyzing the capability of the ORC process of recovering heat from the diesel engine exhaust. The high pressure MDM vapor was expanded through an expansion valve; thus, no power was extracted from the experimental setup and the main focus was on studying the performance of the process heat exchangers. The system under study was identified to be capable of efficiently recovering the waste heat of the exhaust gases, and the potential of using high molecular weight and high critical temperature fluids as the working fluids in high-temperature, small-scale ORC applications was confirmed. It was concluded that when using siloxane MDM as the working fluid, the requirements for the process sealing to withstand low vacuum conditions as well as the effective removal of non-condensable gases during the operation can be identified as one of the major challenges in achieving the targeted power output from this type of ORC systems.

Small-scale gas turbines offer a light weight alternative to engine generators. Despite the many benefits of a micro gas turbine, its efficiency cannot match that of its competitors. This discrepancy is mostly due to Reynolds number losses in turbomachinery but also partly due to internal heat transfer problems, which degrade the performance below what is adiabatically expected. In general, a good understanding about the heat transfer inside the machine is of paramount importance, and innovative engineering solutions are required to improve overall performance. Overall, one of the less exploited areas in the public literature is the effect of the generator cooling approach. Small jet engines can be used as a simple and affordable foundation to produce portable aero derivative micro gas turbines for demonstrating the specific challenges they face but also to study different flow configurations. This study presents combined analytical and experimental analysis of a portable aero derivative micro gas turbine with three main objectives. The first objective is to evaluate the contributions of different heat leakage losses on the overall performance. The second objective is to compare the influence of different generator cooling approaches. And the third objective is to evaluate the effect of different technical modifications. As a result, suggestions are given about the most suitable machine layouts and the importance of several design choices.

The demand for continually improving the efficiency of large diesel engines requires increasing the pressure ratio and efficiency of turbochargers. One answer to these requirements is to use two-stage electrically assisted turbochargers, which will enable higher pressure ratios than before but also generate electricity in sufficient operating conditions. This study shows the design and experimental performance of the novel two-stage single-shaft electrically assisted turbocharger. It was predicted that an increase of 2.5 percentage points in overall efficiency can be achieved by using a two-stage single-shaft intercooled electrically assisted turbocharger in a 1200 kW diesel engine instead of a conventional single-stage turbocharger. It is experimentally shown that the studied turbocharger has potential for improving the engine efficiency although the performance was below the expected. Additionally, the critical points for the design improvements are assessed to guide future development work.

Many waste heat recovery and biomass applications offer opportunities for small-scale steam turbines to produce electricity and to improve systems’ energy efficiency. However, the currently used axial turbine-based technology is generally characterized by a relatively large physical size and poor design and off-design performances. To overcome these challenges, a new compact water-cooled high-speed radial outflow turbine concept is proposed. While the previous understanding of the chosen novel rotor water cooling approach indicates general system feasibility, improved turbine performance, and good potential, the scientific literature lacks relevant information. Since the design of high-speed machines is always case-dependent, every concept must be verified. Hence, to provide verification and new scientific information, this study combines analytical, numerical, and experimental analyses. The results predict turbine performance levels comparable with the previous radial outflow design, and its efficiency was found to exceed those of conventional turbines. During the experiments, the turbine also produced electricity from poor-quality steam, and its rotor dynamic behavior and magnetic bearing performance were close to the predicted results. These findings are considered a verification of the proposed concept. Furthermore, the rotor water cooling approach improved the stability of the system operation and although its physical behavior was not fully resolved, the study was able to verify its feasibility. In addition, at below 200 € /kW, the turbogenerator costs are competitive against competing technologies. Post-print / Final draft

Throughout the world there is pressure to increase distributed energy generation. Driving factors include for example political and environmental concerns in developed countries and reliability in places where centralized grid does not either exist or is too unreliable. The energy generation based on renewable fuels such as biogas is also usually decentralized. To answer this demand, the number of small-scale gas turbine combined heat and power (CHP) installations have increased. Due to its nature, the required power output of distributed generation is highly variable. The power output of decentralized power plant needs to follow the local consumption power need and thus it needs to be efficiently controlled. Therefore, the requirement for variable output necessitates that small-scale gas turbines are often run at part-loads. Previously, most of the installed small-scale gas turbines have been single-spool units with either fixed or variable speed shafts. Control schemes and part-load performance are somewhat different for the two setups. Recently, a two-spool gas turbine where the spools can be controlled independently has been proposed as a feasible alternative. The possibility to produce the desired power output with two spools, both having their own generator, which can be controlled independently of each other, offers significantly more possibilities for the control. Therefore, it might also offer better part-load performance. In this paper, the control schemes of three different small-scale gas turbines are compared. Especially, the part-load electrical efficiency is studied. The studied gas turbines are: a single-spool fixed speed, a single-spool variable speed driven, and a two-spool variable speed driven gas turbine. The part-load performance of different machines is studied and then compared against each other. Furthermore, some estimations are given on how the part-load performance of each machine fares against certain load profiles.

Decentralized electricity and heat production is a rising trend in small-scale industry. There is a tendency towards more distributed power generation. The decentralized power generation is also pushed forward by the policymakers. Reciprocating engines and gas turbines have an essential role in the global decentralized energy markets and improvements in their electrical efficiency have a substantial impact from the environmental and economic viewpoints. This paper introduces an intercooled and recuperated three stage, three-shaft gas turbine concept in 850 kW electric output range. The gas turbine is optimized for a realistic combination of the turbomachinery efficiencies, the turbine inlet temperature, the compressor specific speeds, the recuperation rate and the pressure ratio. The new gas turbine design is a natural development of the earlier two-spool gas turbine construction and it competes with the efficiencies achieved both with similar size reciprocating engines and large industrial gas turbines used in heat and power generation all over the world and manufactured in large production series. This paper presents a small-scale gas turbine process, which has a simulated electrical efficiency of 48% as well as thermal efficiency of 51% and can compete with reciprocating engines in terms of electrical efficiency at nominal and partial load conditions.

Regionally, there has been a lot of focus on the advancement of sustainable arctic industry and circular economy activities within process industry in the Finnish Lapland. In this study, collaboration between university and industry was established facilitated by regional development actors to develop and pilot test a sustainability assessment approach taking into account previous work in this field. The industry partners in this study were a biorefinery investment in the first case and a slag processing service in the second case. As a result of the joint efforts, novel sets of environmental and economic sustainability assessment indicators and associated sub-indicators were developed and the existing set of social indicators was updated. Moreover, environmental and social sustainability assessments were implemented in the biorefinery case accompanied by a separate evaluation of regional economic impacts. In the slag processing case, environmental, economic and social sustainability were assessed. The results of the sustainability assessments indicated very good level of overall performance in both cases. However, specific elements that contributed to lower level of performance included lack of specific sustainability management and reporting approaches and need for better performance in supply chain sustainability, monitoring of greenhouse gas emissions, life cycle thinking and circular economy training. The expected effects of the planned investment on the regional economy were very positive based on the results of the evaluation.

Organic Rankine Cycle (ORC) is a Rankine cycle using organic fluid as the working fluid instead of water and steam. The ORC process is a feasible choice in waste heat recovery applications producing electricity from relatively low-temperature waste heat sources or in applications having a rather low power output. Utilizing waste heat from a large high-efficiency reciprocating engine power plant with ORC processes is studied by means of computations. In addition to exhaust gas heat recovery, this study represents and discusses an idea of directly replacing the charge air cooler (CAC) of a large turbocharged engine with an ORC evaporator to utilize the charge air heat in additional power production. A thermodynamic analysis for ORCs was carried out with working fluids toluene, n-pentane, R245fa and cyclohexane. The effect of different ORC process parameters on the process performance are presented and analyzed in order to investigate the heat recovery potential from the exhaust gas and charge air. A simplified feasibility consideration is included by comparing the ratio of the theoretical heat transfer areas needed and the obtained power output from ORC processes. The greatest potential is related to the exhaust gas heat recovery, but in addition also the lower temperature waste heat streams could be utilized to boost the electrical power of the engine power plant. A case study for a large-scale gas-fired engine was carried out showing that the maximum power increase of 11.4% was obtained from the exhaust gas and 2.4% from the charge air heat.

This study estimates the economic effects of investing in energy efficiency in buildings on a national level. First conservation potentials in space heating for two different scenarios with different levels of investment in energy efficiency are quantified. This was done relying on statistical data and future projections of the development of the building stock. Then economic modeling was used to estimate the effects on energy sector and the economy at large. The results show that a rather modest increase resulting in a few percent rise in annual construction and renovation investments can decrease total primary energy consumption 3.8–5.3% by 2020 and 4.7–6.8% by 2050 compared to a baseline scenario. On the short term a slight decrease in the level of GDP and employment is expected. On the medium to long term, however, the effects on both would be positive. Furthermore, a significant drop in harmful emissions and hence external costs is anticipated. Overall, a clear net benefit is expected from improving energy efficiency.

In gas turbines, a fast decrease of efficiency appears when the output decreases; the efficiency of a large gas turbine (20...30 MW) is in the order of 40 %, the efficiency of a 30 kW gas turbine with a recuperator is in the order of 25 %, but the efficiency of a very small gas turbine (2...6 kW) in the order of 4...6 % (or 8...12 % with an optimal recuperator). This is mainly a result of the efficiency decrease in kinetic compressors, due to the Reynolds number effect. Losses in decelerating flow in a flow passage are sensitive to the Reynolds number effects. In contrary to the compression, the efficiency of expansion in turbines is not so sensitive to the Reynolds number; very small turbines are made with rather good efficiency because the flow acceleration stabilizes the boundary layer. This study presents a system where the kinetic compressor of a gas turbine is replaced with a pulse combustor. The combustor is filled with a combustible gas mixture, ignited, and the generated high pressure gas is expanded in the turbine. The process is repeated frequently, thus producing a pulsating flow to the turbine; or almost a uniform flow, if several parallel combustors are used and triggered alternately in a proper way. Almost all the compression work is made by the temperature increase from the combustion. This gas turbine type is investigated theoretically and its combustor also experimentally with the conclusion that in a 2 kW power size, the pulse flow gas turbine is not as attractive as expected due to the big size and weight of parallel combustors and due to the efficiency being in the order of 8 % to 10 %. However, in special applications having a very low power demand, below 1000 W, this solution has better properties when compared to the conventional gas turbine and it could be worth of a more detailed investigation.

A modern refrigeration process requires constant control to provide required cooling for the user. To properly and economically accommodate this need, a wide operation range of the compressor is necessary. Therefore, it is of interest to investigate the off-design operation of a cooling cycle and compressor. The refrigeration cycle equipped with a two-stage centrifugal compressor and a flash intercooler is studied. The compressor operation maps are generated with two different design codes and the operation values of the compressors are interpolated from the compressor maps in the simulation of the entire cooling cycle. Based on the previous studies of the utilised refrigeration cycle, R245fa is selected as coolant. The aim of this study is to demonstrate the control capacity of the centrifugal compressor and the performance of the cooling loop in off-design conditions. This configuration provides better and wider control over the cooling range than the traditional on-off control of displacement compressors.

Preliminary design and simulation of a free piston engine suitable for small-scale energy production in distributed energy systems is presented in this paper. The properties, particularly the properties of gas seals of the engine are simulated using a simulation program developed for this case, and the results are utilized in preliminary main design parameter selection. The engine simulation program was developed by combining and modifying the source codes of the simulation and calculation programs obtained from Helsinki University of Technology, Tampere University of Technology, and Lappeenranta University of Technology. Because of the contact-free labyrinth seal used in the piston, the efficiency of the motor is lower than the efficiency of a conventional motor with oil lubricated piston rings. On the other hand, the lack of bearing losses, and the lack of losses associated with a crankshaft system and a gearbox, as well as the lack of lubrication oil expenses, compensates this effect. As a net result, this new motor would perform slightly better than the conventional one. Being completely oil-free, it is very environmentally friendly, and its exhaust gases are completely free of oil residuals which are causing problems in normal gas motors.

The optimisation of a refrigeration process with a two-stage centrifugal compressor and flash intercooler is presented in this paper. The two-stage centrifugal compressor stages are on the same shaft and the electric motor is cooled with the refrigerant. The performance of the centrifugal compressor is evaluated based on semi-empirical specific-speed curves and the effect of the Reynolds number, surface roughness and tip clearance have also been taken into account. The thermodynamic and transport properties of the working fluids are modelled with a real-gas model. The condensing and evaporation temperatures, the temperature after the flash intercooler, and cooling power have been chosen as fixed values in the process. The aim is to gain a maximum coefficient of performance (COP). The method of optimisation, the operation of the compressor and flash intercooler, and the method for estimating the electric motor cooling are also discussed in the article.

Power systems based on Organic Rankine Cycle (ORC) technology have been recognized as one of the most promising solutions in converting low- and medium-temperature heat into electricity. In this paper, experimental results of the utilization of charge air heat by means of ORC are presented. The experimental setup consists of a 1.6 MWe diesel engine and an ORC process utilizing charge air heat in which the turbine-generator has been replaced with an expansion valve. Thus, no mechanical or electrical power was extracted from the system and the primary focus of the experiments was to study the performance of the evaporator acting as a charge air cooler. The studied working fluids were R245fa and isopentane. The test runs were carried out at full engine load and at engine part loads. In addition, transient tests were carried out. Based on the measured values the ORC utilizing charge air heat was evaluated to be capable to increase the power output of the test engine by 2%.

Applied general equilibrium models have become a standard tool for the analysis of structural policies in many countries and international research organisations. Their use has been prompted by both developments in economics, but also on the growing need for quantitative policy analysis. The analysis of actual policy options mandates the use of numerical methods, but there are several other reasons to suggest the use of AGE models in particular. Chief among these is the applicability of models that rely on explicit optimisation on the analysis of welfare impacts of structural policies. It may also be the case that many policy issues are intractable by theoretical models, for example, when the policies concern several sectors or regions of the economy, or involve contradicting effects. This report describes the VERM model used in VATT, the Government Institute for Economic Research. The model has been used to study the effects of various tax policies, regional policies, and environmental policies on the economy. Lately, the model has seen extensive use in the anticipation of regional development, especially in the labour markets. The report contains a full description of the model code and its underlying theory. With the help of examples, it also shows how simulation results can be interpreted.

This paper presents a study aimed at evaluating the use of siloxanes as the working fluid of a small-capacity (≈10kWe) ORC turbogenerator based on the “high-speed technology” concept, combining the turbine, the pump, and the electrical generator on one shaft, whereby the whole assembly is hermetically sealed, and the bearings are lubricated by the working fluid. The effects of adopting different siloxane working fluids on the thermodynamic cycle configuration, power output, and on the turbine and component design are studied by means of simulations. Toluene is included into the analysis as a reference fluid in order to make comparisons between siloxanes and a suitable low molecular weight hydrocarbon. The most influential working fluid parameters are the critical temperature and pressure, molecular complexity and weight, and, related to them, the condensation pressure, density and specific enthalpy over the expansion, which affect the optimal design of the turbine. The fluid thermal stability is also extremely relevant in the considered applications. Exhaust gas heat recovery from a 120 kW diesel engine is considered in this study. The highest power output, 13.1 kW, is achieved with toluene as the working fluid, while, among siloxanes, D4 provides the best simulated performance, namely 10.9 kW. The high molecular weight of siloxanes is beneficial in low power capacity applications, because it leads to larger turbines with larger blade heights at the turbine rotor outlet, and lower rotational speed if compares, for instance, to toluene.

Applied general equilibrium models have become a standard tool for the analysis of structural policies in many countries and international research organisations. Their use has been prompted by both developments in economics, but also on the growing need for quantitative policy analysis. The analysis of actual policy options mandates the use of numerical methods, but there are several other reasons to suggest the use of AGE models in particular. Chief among these is the applicability of models that rely on explicit optimisation on the analysis of welfare impacts of structural policies. It may also be the case that many policy issues are intractable by theoretical models, for example, when the policies concern several sectors or regions of the economy, or involve contradicting effects. This report describes the VERM model used in VATT, the Government Institute for Economic Research. The model has been used to study the effects of various tax policies, regional policies, and environmental policies on the economy. Lately, the model has seen extensive use in the anticipation of regional development, especially in the labour markets. The report contains a full description of the model code and its underlying theory. With the help of examples, it also shows how simulation results can be interpreted.

Regional structural change is currently among the greatest challenges facing the public sector in many EU countries. In countries like Finland, where the public sectors have a large role in providing educational, health and social services, structural change rapidly becomes a fiscal problem. Demography is directly linked to the demand for public services and to the potential growth of regional economies. On the one hand, ageing increases the demand for age-related services; on the other, it decreases labour supply, limiting the growth potential of many regions. The state?s main tools for regional policies consist of both direct subsidies to the regions, as well as a mechanism reallocating tax revenues between poor and rich municipalities. However, the welfare costs of funding subsidies to poorer regions may be considerable. Thus, instruments not involving changes in spending have been preferred. Here, we consider the relocation of certain functions of the central government to the periphery ? regionalization ? as an instrument for coping with regional structural change. An improvement in regional municipal finances should also reduce the transfers received from the central government. This study aims at evaluating the effects of regionalization on regional development in recent years and in the near future. The study is related to an ongoing evaluation of the financial relations between the central government and local authorities. Regionalization has in practice meant the relocation of central government jobs. We can cover the relocation of jobs quite accurately, and also had a data to make a plausible valuation of the number of employees that actually relocated with the jobs. Moreover, we are able to calculate state transfers to municipalities at the level of individual municipalities within each region. However, to capture all the implications of relocation to regional economies, we extend the model to take into account the average size and age profile of the families of those who relocate. In this way, we obtain an estimate of the effects of regionalization on demand for public services locally, as well as on the overall effect on local population, labour supply and state, municipal and social security funds? budget balances. We analyse regionalization at the level of the twenty regions of Finland, using a dynamic, regional, AGE model. Our main finding is that regionalization has negative overall economic effects for Finland ? it decreases national product and employment, deteriorates the fiscal balance and increases state transfers to municipalities. However, these effects are small by magnitude. We found that the cumulative decrease in GDP until 2018 was a bit less than 0.05 percentages. The policy altogether succeeds in leveling regional disparities. We also find that while regionalization has been beneficial for many regions by creating new jobs and increasing municipal tax revenues, it has also used resources wastefully as there has been double efforts during the transition period.

Regional, structural change is currently among the greatest challenges facing the public sector in many EU countries at the moment. In countries like Finland, where the public sectors have a large role in providing educational, health and social services, structural change rapidly becomes a fiscal problem. Demography is directly linked to the demand for public services and to the potential growth of regional economies. On the one hand, ageing increases the demand for age-related services; on the other, it decreases labour supply, limiting the growth potential of many regions. The state’s main tools for regional policies consist of both direct subsidies to the regions, as well as a mechanism reallocating tax revenues between poor and rich municipalities. However, the welfare costs of funding subsidies to poorer regions may be considerable. Thus, instruments not involving changes in spending have been preferred. Here, we consider the relocation of certain functions of the central government to the periphery – decentralization – as an instrument for coping with regional structural change. An improvement in regional municipal finances should also reduce the transfers received from the central government. This study aims at evaluating the effects of decentralization on regional development in recent years and in the near future. The study is related to an on-going evaluation of the financial relations between the central government and local authorities. Decentralization has in practice meant the relocation of central government jobs. We can cover the relocation of jobs quite accurately, and we also have the data of the number of employees that actually relocated with the jobs. Moreover, we are able to calculate state transfers to municipalities at the level of individual municipalities within each region. However, to capture all the implications of relocation to regional economies, we extend the model to take into account the average size and age profile of the families of those relocating. In this way, we obtain an estimate on the effects of decentralization on demand for public services locally, as well as on the overall effect on local population, labour supply and state, municipal and social security funds’ budget balances. We analyse decentralization at the level of the twenty regions of Finland, using a dynamic, regional, AGE model. We find that while decentralisation has been beneficial for many regions by creating new jobs and increasing municipal tax revenues, it has also entailed double efforts since there is only limited obligation for the employees to relocate with the jobs. Interestingly, however, this effect is partly off-set by a reduction of transfers to municipalities. Keywords: regional policies, structural change JEL codes: R13, R53

In this study we evaluate the regional effects of ageing and balancing of fiscal deficits by using a dynamic, regional AGE model for Finnish Economy. It uses MONASH-type dynamics. To study the effects of ageing, we make use of econometric results and long term anticipation results conducted by the European Commission for the parameter values determining the population-driven demand for public services. Public demand for age-dependent services is driven by a general growth trend, and by age-group specific parameters. Thus, foreseen changes in the age composition of the Finnish population is reflected the composition and volume of public demand. The study is related to an on-going evaluation of the financial relations especially between the central government and local authorities. The present study introduces also a sub-regional analysis for one of the twenty regions of Finland, the Central Finland region. For the demographic development, we apply the population forecast of the Statistics Finland. Population is kept exogenous in our analysis. State transfers to municipalities include a kind of Robin Hood-element that treats high- and low-income municipalities asymmetrically. In order to improve our description of the state transfers to municipalities, we introduced individual municipalities within each region for the purposes of the state transfer calculus. Transfers to municipalities are traced from statistics and preliminary calculations between 2004 and 2011. From that on, the development of income and population of each municipality is assumed to coincide with the development of the greater region it belongs to. However, the historical status of the municipality within the income distribution is reflected in the amount of transfers it gets during the simulation period. In addition to rules-based transfers to municipalities, around a third of the transfers are based on more ad-hoc policy decisions. This part of the transfers is our policy variable in the analysis. According to our simulation results, constraining the fiscal deficits of the public sector has considerable effects on the GDP growth. The size of effects varies between our alternative ways to curb the deficits: through state-level or municipal income taxation. The negative effects on GDP are greater if the public deficits are financed through higher state income taxes and transfers to the local administration than through municipal income taxation. However, using municipal taxation increases regional differences. As in several studies using new economic theory framework, we find a trade-off between efficiency and cohesion. Future improvements of our model will include making the demographic development endogenous through migration. In addition, commuting between regions may be taken into account explicitly.

In this study we use the dynamic version of the GTAP model to analyse the effects of global trade policy changes and their interaction with different global climate policy regimes from Finland?s point of view, and in particular, implications for Finnish export sectors. Scenarios explore further trade liberalisation as well as effects of higher-than-current tariffs on world markets. As a complementary dimension we analyse the impact of a global climate agreement that will lead to an additional improvement in energy efficiency and impose limitations to GHG emissions. We find a general trend towards a greater weight of services sector in Finland?s total exports volume, whilst the share of traditionally important heavy industry and electronics industries declines. These trends are amplified by further trade liberalisation and slowed down by new barriers for trade. The global coverage of climate policy is particularly significant for energy-intensive industries.

This study evaluates the effects of changes in energy taxes on energy consumption between the years 1995 and 2004 using an applied, general equilibrium model for a historical simulation. During this period, Finnish energy taxation was fundamentally changed, going from an up-stream, emission and energy content-based approach to one with a mixed fuel and electricity tax. The change put the burden more closely on the users of electricity and fuels. We find that while the sharp increases in energy prices since 1995 have significantly restricted the growth of energy demand, energy taxes have also been effective in curbing the growth of energy and especially electricity consumption. For transport fuels, the effective tax rate actually fell as the price net of tax increased over time. Nevertheless, for petrol and light fuel oil we do find the taxes to have slowed down overall demand growth.

In this report we present a new version of the VATTAGE AGE (Applied General Equilibrium) model, which enables distributional analysis of policy changes. We also report estimation results of LES consumption function for eight socioeconomic groups. We use climate policy as an example for the distributional effects. Our model results show that the planned climate policy measures are not very regressive in their nature. In contrast, they seem to distribute the costs of climate policy rather evenly. An exception to this rule is farmer households, the real consumption of which seems to reduce less than that of other groups.

Applied general equilibrium models have become a standard tool for the analysis of structural policies in many countries and international research organisations. Their use has been prompted by both developments in economics, but also on the growing need for quantitative policy analysis. The analysis of actual policy options mandates the use of numerical methods, but there are several other reasons to suggest the use of AGE models in particular. Chief among these is the applicability of models that rely on explicit optimisation on the analysis of welfare impacts of structural policies. It may also be the case that many policy issues are intractable by theoretical models, for example, when the policies concern several sectors of the economy or involve contradicting effects. This report describes the VATTAGE model used in VATT, the Government Institute for Economic Research. The model has been used to study the effects of tax policies and environmental policies on the economy. The model can also be used to study scenarios concerning the driving forces of economic growth and employment. The report contains a full description of the model code and its underlying theory. With the help of examples, it also shows how simulation results can be interpreted.

A centrifugal high-speed compressor is an effective light weight option to power a refrigeration cycle for air conditioning purposes. Perhaps the most important decision in design is the working fluid selection. Modern high-speed technology makes it possible for the refrigeration compressor to be completely oil free, which considerably broadens the scale of possible working fluids. Furthermore, many traditional fluids have become banned and the industry standard R134a might face the same faith in some European countries because of its relatively high global warming potential. In this study eleven different fluids were studied and compared and R22 was used as a reference. It was found that there are many potential fluids for centrifugal compressors that provide better efficiencies than the most common fluids in use today. The purpose of this study is to initially screen a larger set of candidate fluids for more accurate estimation later on. The fluids are evaluated by the efficiency of the cycle, but also mechanical feasibility and dimensions are considered as light weight of the machinery was an important criterion in design process. The comparison was made with constant evaporation and condensation temperature and fixed cooling power for all the fluids. In selection of the working fluid the safety factors often play a dominant role which was also shortly considered. In our study we found out that for a residential HVAC size cooling cycle there are environmentally friendly fluids with high efficiency leading to feasible mechanical designs with centrifugal compressors.Copyright © 2009 by ASME

This study deals with the matter to what extent the costs of the EU Emission Trade System (EU ETS) end up in the electricity prices. The study encompasses both a theoretical and an empirical review of electricity price formation. It includes an econometric analysis of electricity price formation and the impact of EU ETS on power prices. On the basis of the econometric analysis is concluded that cost compensation due to EU ETS is indeed occurring. On average, about 75% to 95% of a price change in EU ETS is passed on to the Finnish NordPool spot price. The analysis also shows that the degree of utilisation of generation capacity (and hence the network loads) have an effect on electricity prices. This hints at possible market imperfections and can aggravate the price effects of EU ETS.

Venäjä on ilmoittanut nostavansa raakapuun vientitulleja asteittain 50 euroon kuutiometriltä, mikä johtaisi toteutuessaan puun tuonnin loppumiseen Venäjältä. Tutkimuksessa pyritään arvioimaan, miten suuria vaikutuksia Venäjän noin 15 miljoonan kuutiometrin suuruisen raakapuun tuonnin loppumisella olisi Suomen metsäsektoriin ja kansantalouteen pitkällä aikavälillä olettaen, että tuontia muualta ei pystytä lisäämään. Tutkimusmenetelmänä on skenaarionanalyysi. Skenaarioita tuotettiin sekä metsäsektorin osittaistasapainomallilla että kansantalouden yleisellä tasapainomallilla. Raakapuun tuonnin aleneminen johtaa kotimaan hakkuiden, kantohintojen ja kantorahatulojen nousuun. Metsätalouden tuotannon arvioidaan olevan noin 7 % suurempi vuonna 2020 verrattuna tilanteeseen ilman tuontimuutosta. Sen sijaan metsäteollisuus joutuisi kustannusten nousun aiheuttaman heikentyneen kannattavuuden vuoksi sopeuttamaan tuotantoansa pienemmäksi. Eniten supistuisi mekaanisen metsäteollisuuden tuotanto, 10–16 % suhteessa perusuraan vuonna 2020 riippuen käytetystä mallista ja lähtöoletuksista. Kansantaloudessa vaikutukset näkyisivät hintojen nousuna, joka alentaisi kulutuskysyntää ja työllisyyttä aluksi noin yhdellä prosentilla ja investointeja hieman tätä enemmän. Talouden rakennemuutos vaimentaa ajan kuluessa hintojen nousun vaikutuksia ja vuonna 2020 ne ovat varsin pieniä koko kansantalouden tasolla. Vaikka Venäjä päätyisi luopumaan tulleista, tutkimus antaa tietoa Suomen talouden riippuvuudesta puun tuonnista.

This study evaluates the long-run effects in Finland of abatement of greenhouse gases with two applied general equilibrium models. Cutting emissions by 20 percent would cause GDP to fall by as much as 3.4 percent in the short run, leading to significant employment effects. In the long run, the labor market may recover, which shifts the burden of adjustment more on the capital markets. It seems likely that energy-intensive industries will contract as a consequence of climate policies. Employment may recover, if the labor markets are flexible enough in the long run. The results highlight the importance of permit prices and CDM prices for the cost of mitigation. Extending participation to flexibility mechanisms would appear very important for the Finnish economy.

Numerical analysis is conducted for the 3-dimensional impeller and vaneless diffuser of a small centrifugal compressor. The influence of impeller tip clearance is investigated. A Navier-Stokes flow solver Finflo has been applied for the simulation. A practical real gas model has been generated for the calculation. Simulations with different sizes of tip clearance at different mass flow rates have been made. The results are compared to experimental results at a certain tip clearance and one operating point. Reasonable agreement has been obtained. The ideal gas model has also been applied to compare with the real gas model. The numerical results show that tip clearance has a significant effect on the performance of a small centrifugal compressor. As the size of tip clearance increases, both the pressure ratio and the efficiency decrease. The decreasing rate of efficiency is higher at higher mass flow rates and lower at lower mass flow rates. The input power of the compressor hardly changes with different sizes of tip clearance, but increases as the mass flow rate increases. The incidence of impeller and flow angle at the exit of the impeller increase as the size of tip clearance increases. Correlations of the size of tip clearance with the efficiency drop and change of flow angle at the exit of impeller are given. The detailed flow distribution shows that as the size of tip clearance increases, the tangential leaking flow at the tip clearance makes the low velocity flow region grow larger and move from the suction-shroud corner to the center of the flow channel. The main flow at the pressure side is compressed and accelerated. Therefore the uniformity of the flow in the whole channel decreases. The detailed flow distribution also shows that the leaking flow is stronger at higher mass flow rates.Copyright © 2006 by ASME

This paper reports on the design procedure to produce radial compressors for high speed applications. These compressors are directly connected to a high speed electric motor. Speed control is used instead of IGV and diffuser vane control, and this sets some additional requirements e.g. for the shape of the compressor performance map. It is required that at the design pressure ratio the compressor has a wide operating range in mass flow, when optimal speed control is used. It is also required that the high efficiency range of the compressor is as wide as possible. One-dimensional computation giving the basic geometry and performance map of the compressor is done with a non-commercial program. Then a geometry generation 3D program is used to define the whole compressor wheel geometry. The wheel geometry data is used in the flow and structure analyses. The compressor flow is calculated with a three-dimensional CFD-program, which has specially been modified for centrifugal compressor flow. Particularly in the optimization process of the volute, also time-dependent computation of the complete compressor using the sliding mesh technique is used. The performance of the final compressor geometry is measured in the University test facility and the test results are used to develop the design process. Up to this date, 15 different high speed compressors have been aerodynamically designed and tested in this design loop. The typical pressure ratio of the compressors ranges from 1.6 to 2.5.

The aim of this study was to make a computer program that simulates a standard refrigeration process, and a process provided with a bubble intercooler. A further object of the study was to establish the suitability of a turbocompressor for small refrigeration plants. Firstly the fundamentals of refrigeration machines and industrial refrigeration systems are discussed. An iteration procedure of steady state refrigeration process calculation is introduced. Fluid properties are calculated with the program units created for the modelling of an ORC power plant. Specific input files were made for 6 process fluids R134a, R123, isopentane, isobutane, toluene and ammonia. The compressor program is linked to the refrigeration process simulation program in order to model single stage and two stage radial compressors. The Turbo Pascal program made for microcomputers is modular, which makes it possible to develop and test the program unit by unit. The maximum deviations of fluid properties from those in tables was found to be less than 1 per cent. To simulate tailor-made refrigeration plants, a simple model is required. On nominal loads the program estimates an optimum intermediate pressure for the bubble process and optimum rotational speed for the radial compressor(s). The lowering of the rotational speed by an inverter gives high COP-values on partial loads of the plant. Based on the example calculation, a two stage turbocompressor calculated with isopentane as the working fluid, a cooling capacity of 1200 W seems to be feasible.

The economic effects of investing in energy efficiency in buildings in Finland was estimated. First conservation potentials in space heating for two different scenarios with different levels of investment in energy efficiency were quantified. This was done relying on statistical data and future projections of the development of the building stock. Then economic modelling was used to estimate the effects on energy sector and the economy at large. The results show that a rather modest increase resulting in a few percent rise in annual construction and renovation investments can decrease total primary energy consumption 3.8-5.3 % by 2020 and 4.7-6.8 % by 2050 compared to a baseline scenario. On the short term a slight decrease in the level of GDP and employment is expected. On the medium to long term, however, the effects on both would be positive. The rebound effect is estimated to stay within the range typical to OECD countries, that is, under 60 % of energy saved. Furthermore, a significant drop in harmful emissions and hence external costs is anticipated. Overall, a clear net benefit is expected from adopting the energy conservation measures. The study demonstrates that improvements in the energy efficiency of buildings are an economically sound and effective way to save energy. The required investments carry manageable costs. Furthermore, the results show that the energy sector can adapt quite painlessly to the changes, the most significant effect being a generally lower need for new energy production capacity.