5,669 research outputs found
Guidelines for Impact Assessment in Law Drafting
These guidelines replace the Guidelines for Impact Assessment in Law Drafting issued by the Government in 2007. The purpose of the revised guidelines is to improve the quality of impact assessments and thus the acts to be drafted. The guidelines help law drafters plan impact assessments, identify and assess different types of impacts and, where necessary, seek further information.
The first part of the guidelines lays down general principles for impact assessments. This part deals with starting points for an impact assessment, the stages of the impact assessment as part of the law drafting process, the special features of impact assessments in projects concerning EU legislation and treaties, and information collection, methods and documentation in connection with impact assessments.
The second part of the guidelines provides instructions on special questions related to the assessment of different types of impacts. The guidelines describe what the different types of impacts mean, how they can be assessed, and what information sources are available for this purpose. The impacts to be assessed are divided into economic impacts, environmental impacts and other human and societal impacts.
In addition, the guidelines contain a checklist for the impact assessment process, a checklist for the identification of impacts and a list of further instructions and information sources referred to in the guidelines
Urbanised forested landscape: Urbanisation, timber extraction and forest care on the Vișeu Valley, northern Romania
By looking at urbanisation processes from the vantage point of the forest, and the ways in which it both constitutes our living space while having been separated from the bounded space of the urban in modern history, the thesis asks: How can we (re)imagine urbanisation beyond the limits of the urban? How can a feminine line of thinking engage with the forest beyond the capitalist-colonial paradigm and its extractive project? and How can we “think with care” (Puig de la Bellacasa 2017) towards the forest as an inhabitant of our common world, instead of perpetuating the image of the forest as a space outside the delimited boundaries of the city? Through a case study research, introducing the Vișeu Valley in northern Romania as both a site engaged in the circulation of the global timber flow, a part of what Brenner and Schmid (2014) name “planetary urbanisation”, where the extractive logging operations beginning in the late XVIIIth century have constructed it as an extractive landscape, and a more than human landscape inhabited by a multitude of beings (animal, plant, and human) the thesis argues towards the importance of forest care and indigenous knowledge in landscape management understood as a trans-generational transmission of knowledge, that is interdependent with the persistence of the landscape as such. Having a trans-scalar approach, the thesis investigates the ways in which the extractive projects of the capitalist-colonial paradigm have and still are shaping forested landscapes across the globe in order to situate the case as part of a planetary forest landscape and the contemporary debates it is engaged in. By engaging with emerging paradigms within the fields of plant communication, forestry, legal scholarship and landscape urbanism that present trees and forests as intelligent beings, and look at urbanisation as a way of inhabiting the landscape in both indigenous and modern cultures, the thesis argues towards viewing forested landscapes as more than human living spaces. Thinking urbanisation through the case of the Vișeu Valley’s urbanised forested landscape, the thesis aligns with alternate ways of viewing urbanisation as co-habitation with more than human beings, particularly those emerging from interdisciplinary research in the Amazon river basin (Tavares 2017, Heckenberger 2012) and, in light of emerging discourses on the rights of nature, proposes an expanded concept of planetary citizenship, to include non-human personhood
Assessing Atmospheric Pollution and Its Impacts on the Human Health
This reprint contains articles published in the Special Issue entitled "Assessing Atmospheric Pollution and Its Impacts on the Human Health" in the journal Atmosphere. The research focuses on the evaluation of atmospheric pollution by statistical methods on the one hand, and on the other hand, on the evaluation of the relationship between the level of pollution and the extent of its effect on the population's health, especially on pulmonary diseases
Advances in Binders for Construction Materials
The global binder production for construction materials is approximately 7.5 billion tons per year, contributing ~6% to the global anthropogenic atmospheric CO2 emissions. Reducing this carbon footprint is a key aim of the construction industry, and current research focuses on developing new innovative ways to attain more sustainable binders and concrete/mortars as a real alternative to the current global demand for Portland cement.With this aim, several potential alternative binders are currently being investigated by scientists worldwide, based on calcium aluminate cement, calcium sulfoaluminate cement, alkali-activated binders, calcined clay limestone cements, nanomaterials, or supersulfated cements. This Special Issue presents contributions that address research and practical advances in i) alternative binder manufacturing processes; ii) chemical, microstructural, and structural characterization of unhydrated binders and of hydrated systems; iii) the properties and modelling of concrete and mortars; iv) applications and durability of concrete and mortars; and v) the conservation and repair of historic concrete/mortar structures using alternative binders.We believe this Special Issue will be of high interest in the binder industry and construction community, based upon the novelty and quality of the results and the real potential application of the findings to the practice and industry
Air pollution, nanotoxicity and neurodegeneration; exploring the relationship between environmental metallic nanoparticles and human health
Air pollution and Alzheimer’s disease (AD) are two of the largest global health issues faced by society today; air pollution is a recognised risk factor for AD. Particulate matter (PM) is a major component of air pollution and refers to the solid and liquid particulates of varying sizes and compositions that are resuspended in the air. Of these particles, metallic particles in the nanometre range (ultrafine, UFPs; < 0.1 µm) are particularly hazardous due to their pervasiveness, ability to penetrate all major organs in the human body, and ability to generate both inflammatory and oxidative stress responses in humans. Magnetite (Fe3O4) nanoparticles (MNPs) and related iron oxides may be of relevance to neurodegeneration. MNPs are found within PM, typically in association with toxic metals, and have been found throughout the human brain, including in association with senile plaques (a key pathological hallmark of AD). MNPs have also been shown to accelerate amyloid beta (Aβ) toxicity and aggregation. MNPs have previously been quantified in a handful of studies to compare AD and control tissue, with mixed results. Improved understanding of the development of AD, the toxic effects of air pollution (especially magnetite and metals), and the relationship between these two phenomena would be highly beneficial to global health. In order to explore the potential causal link between air pollution and AD, two approaches were taken; metallic and magnetic quantification of post-mortem human brain tissue via superconducting quantum interference device (SQUID) magnetometry and inductively couple plasma mass spectrometry (ICP-MS), and exploration of the cytotoxic effects of ultrafine roadside dust particles (UF-RDPs) on human lung epithelial cells (Calu-3) using different in vitro assays. The concentration of magnetite (measured as magnetic remanence, SIRM) in human brain tissue was not statistically different when comparing AD cases to aged-matched controls. Similarly, there were no differences in metal content between the two groups. Principal component analysis grouped the metals into four components, which are potentially indicators of pollution sources: (1) traffic-related and crustal, (2) fuel oil combustion, (3) biological and tyre/brake wear, and (4) catalytic converters and dental alloys. The distributions of magnetite and metals were heterogenous across different individuals. Significantly lower concentrations of both MNPs and metals were reported in UK samples, compared topreviously reported Mexico City samples. Differences were also seen when comparing the in vitro response to UF-RDPs from three contrasting cities; Lancaster UF-RDPs increased cell viability, whilst Mexico City UF-RDPs were the most toxic and induced the highest amount of oxidative stress (ROS production), and Birmingham UF-RDPs were the most pro-inflammatory. These responses are not fully reflected in conventional mass metrics like PM10, as although the greatest cytotoxicity and ROS production was seen with Mexico City UF-RDPs (highest PM10 exposure), the strongest pro-inflammatory responses were seen in response to Birmingham UF-RDPs and a potentially tumorigenic or fibrosis related increase in cell viability was seen in response to Lancaster UF-RDPs despite the lower PM10 and PM2.5 exposures in the UK cities. There is a need for localised air pollution limits which use biologically relevant metrics that address particle size and cover non-exhaust emission sources of PM like road dust to minimize the health risks of air pollution exposure. Overall, this work demonstrates the presence of exogenous, pollution-derived metals and magnetic nanoparticles within the human brain. Highly reactive and toxic metals and MNPs may exert toxic effects in the brain and have been causally linked to neurodegeneration and AD. The geriatric blood-brain barrier is likely compromised allowing for universal incursion in both AD and age-matched controls, so the use of younger highly exposed individuals such as Mexico City urbanites is critical to identify any changes in metal/magnetic content in the brain decades prior to the presentation of AD. Clear differences were seen across geographical locations when looking at absolute concentrations of MNPs, as well as the composition and induced biological effects of UF-RDPs from different cities. It is thus important to focus on highly localised air pollution regulations to mitigate risk to human health
Public sector accounting and financial management in the context of a developing country: an empirical study of the Volta River Authority in Ghana
Using the Volta River Authority, a major Ghanaian corporation responsible for the generation and distribution of electricity in Ghana and neighbouring countries, as a case study, this thesis seeks to gain an empirical understanding of the nature and effectiveness of accounting and financial management systems in the context of a public sector organisation in a developing country. The principal rationale of the thesis is an attempt to substantiate and illuminate major issues and concerns about the nature of accounting and financial management systems in public sector organisations of developing countries today. The thesis problematises an overly simple view that developing countries have deficient accounting and financial management systems in their public sector organisations.
The methodological, epistemological, and ontological orientations of the thesis are consistent with what Chua (1986) labels the “interpretive” paradigm. A recognition of multiple realities in the functioning of accounting enables an exploration of the claim that developing countries have deficient public sector accounting and financial management systems in a three-dimensional fashion. Firstly, the perceptions of organisational actors are drawn upon to aid evaluation of the basic deficiency claim. The research at this level emphasizes the technical-rational view of accounting as a tool for control over organisational financial resources. Thick descriptions of the systems for managing financial resources (including planning, budgeting, pricing, extent of computerisation, financial reporting and audit practices) of the VRA are gathered from organisational actors together with perceptions of the accounting and financial management systems by external constituencies such as the World Bank and the Authority’s multinational audit firms as a basis for evaluating the deficiency claim in the context of the VRA. Secondly, the thesis draws upon social theory (the view of organisations as negotiated orders) to further interpret the deficiency claim by bringing into the analysis the socio-historical circumstances of the organisation and how they help to provide insights into how the systems for financial resource management arise at the VRA. At this level of analysis, the thesis provides an interpretive construction of the technical procedures for financial resource management against the backdrop of the institutional setting within which the Authority conducts its operations. To this end, the influence of external constituencies such as the World Bank and the Volta Aluminium Company (VRA’s major customer) on the Authority’s accounting and financial management systems are explored. Thirdly, the thesis evaluates the effectiveness of the Authority’s accounting and financial management systems with reference to the extent to which they assist in the accomplishment of the principal rationale for establishing the organisation (i.e. socio-economic development of Ghana). At the third level of analysis, the Brundtland Commission’s notion of sustainable development is drawn upon as an alternative to the dominant economistic notion of development to provide a benchmark for the analysis. Employing the Commission’s perspective, the thesis attempts to understand the extent to which VRA’s systems of financial resource management reflect the notion of people-centredness and environmental awareness (i.e. the two major strands of the Commission’s notion of sustainable development).
Multiple methods, including interviews, observation, document analysis and survey are employed to collect empirical evidence for this study. The major conclusions of the study are that from a technical-rational perspective, the claim that developing countries generally have deficient public sector accounting and financial management systems could not be established in the context of the VRA. This conclusion derived from the overwhelming positive perception of the Authority’s financial resource management systems by organisational actors, international funding agencies such as the World Bank, and the Authority’s multinational accounting/audit firms. Indeed, the claims about the lack of published annual accounts, inadequate information for managerial decision making, poor budgetary practices, and lack of independent auditors in developing country public sector contexts could not be supported in the case of the VRA. However, by going behind the technical procedures (façade) to uncover the forces which explain how the systems arise, the thesis argued that the deficiency claim might be supported in another sense; a sense which appreciates and problematises the socio-historical and institutional setting which are strongly responsible not only for the nature of the Authority’s current systems but how they have changed over time. In particular, the thesis argues that the systems of financial resource
management are constructed partly to legitimise outcomes of prior negotiations between the Authority and its external constituencies. The constraints presented by these prior agreements and contracts render some of the Authority’s systems of financial resource management inconsistent with explanations grounded in conventional accounting and financial management logic. The thesis also finds, however, that some of the inadequacies observed with VRA’s systems of financial resource management reflected general limitations of conventional accounting with its over-emphasis on the entity concept rather than a peculiar organisational or even developing country problem.
By employing an interpretive methodological approach to gain an understanding of the nature and effectiveness of accounting in a third world public sector organisational context, this thesis illuminates hitherto relatively unappreciated issues, including furthering an appreciation of accounting as a socio-political artefact in this context, and thus contributes to the critical and interpretive accounting literature
A Simulation of the Impacts of Climate Change on Civil Aircraft Takeoff Performance
Climate change affects the near-surface environmental conditions that prevail at airports worldwide. Among these, air density and headwind speed are major determinants of takeoff performance, and their sensitivity to global warming carries potential operational and economic implications for the commercial air transport industry. Previous archival and prospective research observed a weakening in headwind strength and predicted an increase in near-surface temperatures, respectively, resulting in an increase in takeoff distances and weight restrictions. The main purpose of the present study was to update and generalize the extant prospective research using a more representative sample of worldwide airports, a wider range of climate scenarios, and next-generation climate models. The research questions included how much additional thrust and payload removal will be required to offset the centurial changes in takeoff conditions. This study relied on a quantitative method using the simulation instrument. Forecast climate data corresponding to four shared socioeconomic pathways (SSP1‒2.6, SSP2‒4.5, SSP3‒7.0, and SSP5‒8.5) over the available 2015‒2100 period were sourced from a high-resolution CMIP6 global circulation model. These data were used to characterize the six-hourly near-surface environmental conditions prevailing at all 881 airports worldwide having at least one million passengers in pre-COVID‒19 traffic. The missing air density was iii numerically derived from the air temperature, pressure, and humidity variables, while the headwind speed for each airport’s active runway configuration was triangulated from the wind vector components. Separately, a direct takeoff-dynamics simulation model was developed from first principles and calibrated against published performance data under international standard atmospheric conditions for two narrowbody and two widebody aircraft. The model was used to simulate 1.8 billion unique takeoffs, each initiated at 75% of maximum takeoff thrust and 100% of maximum takeoff mass. When the resulting takeoff distance required exceeded that available, the takeoff thrust was gradually increased to 100%, after which the takeoff mass was gradually decreased to an estimated breakeven load factor. In total, 65 billion takeoff iterations were simulated. Longitudinal changes to takeoff thrust, distance, and payload were recorded and examined by aircraft type, climate scenario, and climate zone. The results show that despite a marked centurial increase in the global mean air temperature of 9.4%‒18.0% relative to the year 2015 under SSP2‒4.5 and SSP3‒7.0, air density will only decrease by 0.6%‒1.1% due to its weak sensitivity to temperature. Likewise, mean headwinds were observed to remain almost unchanged relative to the 2015 baseline. As a result, the global mean takeoff thrust was found to increase by no more than 0.3 percentage point while payload removals did not exceed 1.1 passenger. Significant deviations from the mean were observed at climatic outlier airports, including those located around the Siberian plateau, where takeoff operations may become more difficult. This study contributes to the air transport climate adaption body of knowledge by providing contrasting results relative to earlier research that reported strong impacts of global warming on takeoff performance
Aerosol modelling : Improving the understanding of aerosol processes and their effects on the climate at process and global-scale
Atmospheric aerosol particles have the ability to affect climate through cloud interactions and direct scattering and absorption of radiation. These aerosol particles can also affect human health through respiratory system. Aerosol particles are emitted to the atmosphere through direct sources or they can be formed through chemical processes from gas phase precursors. The different atmospheric processes and climate feedbacks of aerosol particles can be studied using process-scale models as well as larger global-scale models. In recent years, it has been found out that certain aerosol species lack information on their thermodynamic properties, causing uncertainties in process-scale modelling as well as global-scale modelling. In addition, transport of aerosols to remote regions, where emissions of aerosol particles are low, is poorly modelled in global-scale models. Furthermore, sources for formed secondary organic aerosol (SOA) include uncertainties in global aerosol-climate models, which causes uncertainty to estimating the radiative forcing (RF).
In this thesis, these aspects relating to uncertainties are addressed using process and global-scale modelling. This was done first by evaluating the capability of thermodynamic equilibrium model to reproduce observed hygroscopicity in terms of dimethylamine, sulfuric acid and ammonia containing particles. Second, an in-cloud wet deposition scheme was developed (hereafter referred to as the newly-developed scheme) for global models which use sectional aerosol description. The newlydeveloped wet deposition scheme was tested using ECHAM-HAMMOZ global aerosol-climate model with Sectional Aerosol model for Large-Scale Applications (SALSA) in terms of aerosol vertical distributions and lifetimes. Third, the biotic stress effects to trees over boreal region and their effects to SOA formation, clouds and radiative effects were studied using ECHAM-HAMMOZ with SALSA.
The results showed that when the thermodynamic equilibrium model was used to model particles with sizes of the order of couple of tens of nanometers, it was inadequate in estimating the hygroscopic growth of dimethylamine (DMA), sulfuric acid (SA) and ammonia containing particles. Thus, more investigation is needed in terms of thermodynamics of DMA containing systems to properly evaluate its effects to climate. Global aerosol-climate models are very complex and thus making aerosol processes more physically sound can even impair the results. This was seen in the results of the newly-developed, more physical, in-cloud wet deposition scheme as it produced spurious vertical profiles and atmospheric black carbon lifetime when compared to the preexisting scheme. Especially, the atmospheric lifetime of black carbon, in the newly-developed scheme, was 1.6 times longer than in the pre-existing scheme and over 2.6 times longer than has been suggested by experimental studies. Thus, the sensitivity of the newly-developed scheme was tested in terms of internal mixing and emission size distribution of black carbon as well as ageing of aerosol species. These results showed that mixing black carbon with soluble substances produced best results in comparison with the observations as well as atmospheric lifetimes of aerosol species when compared to AEROCOM model means. Lastly, the results studying the biotic stress effects on climate showed that increasing the extent of stress in boreal trees enhanced SOA formation as the emissions of volatile organic compounds (VOCs) were increased. The enhanced SOA formation increased cloud droplet number concentration (CDNC) at cloud top and caused stronger negative RF in both all-sky and clear-sky cases. In the future, aerosol model development should investigate further on the thermodynamic properties of aerosol species, especially with respect to DMA. The wet removal and extent of internal mixing of different aerosol species, especially black carbon, should be further investigated and revised, in global climate models, to properly evaluate the transport of aerosol particles. In addition, sources of atmospheric SOA needs further investigation to properly describe its behaviour in the atmosphere as well as the effects on the climate.Ilmakehän aerosolihiukkasilla on kyky vaikuttaa ilmastoon pilvivuorovaikutusten kautta sekä suoraan sirottamalla ja absorboimalla itseensä säteilyä. Nämä aerosolihiukkaset voivat myös vaikuttaa ihmisterveyteen hengityselimien kautta. Aerosolihiukkasia vapautuu ilmakehään suorien lähteiden kautta tai ne voivat syntyä kemiallisissa prosesseissa kaasufaasin esiasteista. Eri aerosoliprosesseja ja aerosolihiukkasten ilmastovaikutuksia voidaan tutkia käyttäen prosessi- ja globaalin mittakaavan malleja. Viime vuosina on havaittu, että tietyiltä aerosoliyhdisteiltä puuttuu tietoja niiden termodynaamisista ominaisuuksista, joka aiheuttaa epävarmuutta prosessi- ja globaalitason mallinnuksessa. Lisäksi aerosolien kaukokulkeuma syrjäisille alueille, joilla aerosolihiukkasten päästöt ovat vähäisiä, on heikosti mallinnettu globaalin mittakaavan malleissa. Lisäksi sekundaarisen orgaanisen aerosolin (SOA) päästölähteet sisältävät epävarmuuksia globaalin mittakaavan malleissa, joka aiheuttaa epävarmuutta säteilypakotteen arvioinnissa.
Tässä työssä näitä näkökohtia, jotka liittyvät kyseisiin epävarmuuksiin, käsitellään käyttäen prosessi- ja globaalin mittakaavan mallinnusta. Tämä tehtiin ensiksi arvioimalla termodynaamisen tasapainomallin kykyä kuvata dimetyyliamiinia, rikkihappoa ja ammoniakkia sisältävien hiukkasten vedenottokykyä verrattuna mittauksiin. Toiseksi työssä kehitettiin pilven sisäinen märkäpoistumajärjestelmä globaalitason malleille, jotka käyttävät kokoon perustuvaa aerosolikuvausta. Vasta kehitettyä märkäpoistumajärjestelmää testattiin aerosolien pystyprofiilien ja elinikien suhteen käyttämällä ECHAM-HAMMOZ globaalia aerosoli-ilmastomallia, joka sisälsi ”Sectional Aerosol model for Large-Scale Applications (SALSA)” -mikrofysiikkakuvauksen. Kolmanneksi tutkittiin havumetsävyöhykkeen puihin kohdistuneen bioottisen stressin vaikutusta SOA:n muodostumiseen, pilviin ja säteilyvaikutuksiin käyttämällä ECHAM-HAMMOZ:ia SALSA:n kanssa.
Tulokset osoittivat, että kun termodynaamista tasapainomallia käytettiin mallinnettaessa hiukkasia, joiden koko oli muutamien kymmenien nanometrien luokkaa, malli oli epäpätevä arvioimaan dimetyyliamiinia (DMA), rikkihappoa ja ammoniakkia sisältävien hiukkasten hygroskooppisuutta. Näin ollen lisätutkimuksia tarvitaan DMA:a sisältävien systeemien termodynamiikasta, jotta voidaan arvioida kunnolla sen vaikutusta ilmastoon. Globaalit aerosoli-ilmastomallit ovat erittäin monimutkaisia ja siksi aerosoliprosessien muuttaminen fysikaalisemmaksi voi jopa heikentää tuloksia. Tämä havaittiin vasta kehitetyn, fysikaalisemman, märkäpoistumajärjestelmän tuottamista tuloksista, jotka osoittivat kehitetyn menetelmän tuottavan harhaanjohtavia pystyprofiileja sekä vääristävän mustan hiilen elinikää verrattuna aiempaan järjestelmään. Erityisesti mustan hiilen elinikä, vasta kehitetyssä järjestelmässä, oli 1.6 kertaa pidempi kuin aiemmassa järjestelmässä ja yli 2.6 kertaa pidempi kuin kokeellisissa tutkimuksissa on ehdotettu. Siksi vasta kehitetyn järjestelmän herkkyyttä testattiin mustan hiilen sisäisen sekoittumisen ja päästökokojakauman sekä aerosoliyhdisteiden ikääntymisen kannalta. Nämä tulokset osoittivat, että mustan hiilen sekoittaminen liukoisten yhdisteiden kanssa tuotti parhaat tulokset verrattuna havaintoihin sekä aerosoliyhdisteiden eliniät verrattuna AEROCOM mallien keskiarvoihin. Lopuksi tulokset, joissa tutkittiin bioottisen stressin vaikutusta ilmastoon, osoittivat, että stressin lisääminen havumetsävyöhykkeen puissa lisäsi SOA:n muodostumista, koska haihtuvien orgaanisten yhdisteiden päästöt lisääntyivät. Lisääntynyt SOA:n muodostus lisäsi myös pilvipisaroiden lukumäärää pilvien yläpinnassa sekä aiheutti voimakkaamman negatiivisen säteilypakotteen. Tulevaisuudessa aerosolimallikehityksessä tulisi tutkia tarkemmin aerosoliyhdisteiden termodynaamisia ominaisuuksia erityisesti DMA:n suhteen. Märkäpoistumaa sekä eri aerosoliyhdisteiden, erityisesti mustan hiilen, sisäisen sekoittumisen määrää tulisi tutkia ja uudistaa globaaleissa ilmastomalleissa, jotta aerosolihiukkasten kaukokulkeumaa voitaisiin arvioida kunnolla. Lisäksi ilmakehän SOA:n lähteet tarvitsevat lisätutkimusta, jotta sen käyttäytymistä ilmakehässä ja ilmastovaikutuksia voitaisiin kuvata oikein
Outdoor Insulation and Gas Insulated Switchgears
This book focuses on theoretical and practical developments in the performance of high-voltage transmission line against atmospheric pollution and icing. Modifications using suitable fillers are also pinpointed to improve silicone rubber insulation materials. Very fast transient overvoltage (VFTO) mitigation techniques, along with some suggestions for reliable partial discharge measurements under DC voltage stresses inside gas-insulated switchgears, are addressed. The application of an inductor-based filter for the protective performance of surge arresters against indirect lightning strikes is also discussed
Investigation of Inorganic Salt Hydrate Phase Change Materials for Thermal Energy Storage Integrated into Heat Pump Systems
Thermal energy storage (TES) is a promising technology for the Energy Transition. Low grade heat is valuable for many everyday applications: indoor heating and cooling, hot water, refrigeration, etc. Heat pumps (HPs) move heat up a thermal gradient (from cold to hot) with an input of energy. Integrating TES into a HP grants flexibility to dispatch the stored heat as needed. When operating a HP against a fluctuating temperature body (i.e., outdoor ambient air temperature), TES provides an isothermal heat source that enables more efficient HP operation to its reduce energy consumption without sacrificing thermal comfort. This work explores the thermodynamic limits of HP-TES and it was found that TES temperatures equal to the application temperature leads to the highest potential for energy savings and peak demand reduction. This HP-TES system was then modeled in a building thermal energy simulation where the same findings emerge: a TES temperature near the application temperature shows the highest potential. A common method of achieving an isothermal TES is to incorporate phase change materials (PCMs) that store heat through the enthalpy of phase change. Salt hydrates are valued for their high volumetric storage density and low cost. This work explores the Brunauer-Emmett-Teller method to model sodium sulfate, but this salt was found to be incompatible with this reduced order method. Salt hydrates also exhibit low thermal conductivity which limits their direct use in TES. This work develops salt hydrate-graphite composite PCMs with improved thermal conductivity, however a tradeoff between energy storage capacity and thermal power density was seen. The composite PCMs were experimentally tested in a TES device and the improved thermal properties demonstrate their potential for use in simple TES architectures. Overall, this work evaluated TES systems from a holistic perspective, spanning several orders of magnitude, both energetically and spatially.Ph.D
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