Economist, PhD candidate
Maintenance, upgrading and extension of the Decision Support System for the management of the Athens water resource system
Duration: October 2008–November 2011
Budget: €72 000
Project director: N. Mamassis
Principal investigator: D. Koutsoyiannis
This research project includes the maintenance, upgrading and extension of the Decision Support System that developed by NTUA for EYDAP in the framework of the research project “Updating of the supervision and management of the water resources’ system for the water supply of the Athens’ metropolitan area”. The project is consisted of the following parts: (a) Upgrading of the Data Base, (b)Upgrading and extension of hydrometeorological network, (c) upgrading of the hydrometeorological data process software, (d) upgrading and extension of the Hydronomeas software, (e) hydrological data analysis and (f) support to the preparation of the annual master plans
A. Liakopoulou, C. Makropoulos, D. Nikolopoulos, K. Monokrousou, and G. Karakatsanis, An urban water simulation model for the design, testing and economic viability assessment of distributed water management systems for a circular economy, Environmental Sciences Proceedings, 21 (1), 14, doi:10.3390/environsciproc2020002014, 2020.
The concept of Circular Economy, although not entirely new, has in recent years gained traction due to growing concern with regards to the Earth’s natural reserves. In this context, Sewer Mining, a wastewater management method based on extracting wastewater from local sewers for reuse applications, presents an interesting option that lies in the interplay between reuse at a household scale and centralized reuse at a wastewater treatment plant. As part of the EU-funded program NextGenWater, a new unit is being prepared for operation in Athens’s Plant Nursery, in Goudi. This paper examines the water flow within the proposed installation, using the Urban Water Optioneering Tool (UWOT). Further research is focused on the economic viability of Sewer Mining and the proposed investment. The results produced are promising regarding Sewer Mining’s capabilities and benefits, as well as its future prospects, in the hopes that this technology can provide an attractive alternative to conventional water sources within the urban water cycle.
Full text: http://www.itia.ntua.gr/en/getfile/2060/1/documents/environsciproc-02-00014.pdf (992 KB)
See also: https://www.mdpi.com/2673-4931/2/1/14
G.-F. Sargentis, R. Ioannidis, G. Karakatsanis, S. Sigourou, N. D. Lagaros, and D. Koutsoyiannis, The development of the Athens water supply system and inferences for optimizing the scale of water infrastructures, Sustainability, 11 (9), 2657, doi:10.3390/su11092657, 2019.
Modern organized societies require robust infrastructures, among which hydraulic projects, such as water supply and drainage systems, are most important, particularly in water-scarce areas. Athens is a unique example because it is a big city (population 3.7 million) located in a very dry area. In order to support the development of the city, large hydraulic projects had to be constructed during its history and, as a result, Athens currently has one of the largest water supply systems in the world. Could Athenians choose smaller scale infrastructures instead? Analyzing social, technical and economical historical data, we can see that large capital investments were required. In order to evaluate these investments this paper presents a technical summary of the development. An economic analysis displays historical values of these investments in present monetary values. The cost of existing infrastructure is compared to the cost of constructing smaller reservoirs and a model is created to correlate the price of water and the cost of water storage with the size of reservoirs. In particular, if more and smaller reservoirs were built instead of the large existing ones, the cost of the water would significantly increase, as illustrated by modelling the cost using local data.
Full text: http://www.itia.ntua.gr/en/getfile/1970/1/documents/sustainability-11-02657-v3.pdf (6450 KB)
See also: https://www.mdpi.com/2071-1050/11/9/2657
E. Klousakou, M. Chalakatevaki, P. Dimitriadis, T. Iliopoulou, R. Ioannidis, G. Karakatsanis, A. Efstratiadis, N. Mamassis, R. Tomani, E. Chardavellas, and D. Koutsoyiannis, A preliminary stochastic analysis of the uncertainty of natural processes related to renewable energy resources, Advances in Geosciences, 45, 193–199, doi:10.5194/adgeo-45-193-2018, 2018.
The ever-increasing energy demand has led to overexploitation of fossil fuels deposits, while renewables offer a viable alternative. Since renewable energy resources derive from phenomena related to either atmospheric or geophysical processes, unpredictability is inherent to renewable energy systems. An innovative and simple stochastic tool, the climacogram, was chosen to explore the degree of unpredictability. By applying the climacogram across the related timeseries and spatial-series it was feasible to identify the degree of unpredictability in each process through the Hurst parameter, an index that quantifies the level of uncertainty. All examined processes display a Hurst parameter larger than 0.5, indicating increased uncertainty on the long term. This implies that only through stochastic analysis may renewable energy resources be reliably manageable and cost efficient. In this context, a pilot application of a hybrid renewable energy system in the Greek island of Astypalaia is discussed, for which we show how the uncertainty (in terms of variability) of the input hydrometeorological processes alters the uncertainty of the output energy values.
Full text: http://www.itia.ntua.gr/en/getfile/1864/1/documents/adgeo-45-193-2018.pdf (559 KB)
See also: https://www.adv-geosci.net/45/193/2018/
C. Makropoulos, E. Rozos, I. Tsoukalas, A. Plevri, G. Karakatsanis, L. Karagiannidis, E. Makri, C. Lioumis, K. Noutsopoulos, D. Mamais, K. Ripis, and T. Lytras, Sewer-mining: A water reuse option supporting circular economy, public service provision and entrepreneurship, Journal of Environmental Management, 216, 285–298, doi:10.1016/j.jenvman.2017.07.026, 2018.
Water scarcity, either due to increased urbanisation or climatic variability, has motivated societies to reduce pressure on water resources mainly by reducing water demand. However, this practice alone is not sufficient to both protect resources and guarantee the quality of life water services underpin especially within a context of increased urbanisation. As such, the idea of water reuse has been gaining momentum for some time in the water sector and has recently found a more general context within the emerging concept of the Circular Economy. As a result of this growing trend, water recycling schemes at various scales have been applied worldwide. The most common scale of water reuse is reusing the effluent of a wastewater treatment plant for irrigation or industrial uses (e.g. cooling towers, or rinsing). This is favoured by economies of scale, but to be economically viable it requires that the recycled-water user is close enough to the treatment plant (and at a more or less similar or lower elevation), otherwise capital and operational costs for transmission getratherhigh. Another downside with this scale of (centralised) reuse is that this scheme does not break the monopoly of water supply, since it is again the water company that runs the treatment unit and provides the effluent for reuse and as such offers reduced benefits in terms of job creation, innovation drive and entrepreneurship. On the other side of the scale spectrum, at the level of the household, reuse options include mostly the reuse of grey water for non-potable uses (such as toilet flushing and garden irrigation). Although promising and with significant potential for demand reduction, this scale of reuse is not necessarily cost effective, with all costs borne by the end user, and usually relies on additional motivation, such as drought conditions or environmental attitudes to be implemented. This study argues for an intermediate scale of water reuse, termed sewer-mining, which is a water recycling scheme at the neighbourhood scale. We suggest it provides a feasible alternative reuse option when the geography of the wastewater treatment plant is problematic, it relies on mature treatment technologies and presents an excellent opportunity for Small Medium Enterprises (SME) to be involved in the water supply market, thus securing both environmental, social and economic benefits (including but not restricted to water for ecosystem services). To support this argument, we report on a pilot sewer mining application. The pilot, integrates to important subsystems: a packaged treatment unit and an Information and Communications Technology (ICT) infrastructure that would allow an operator to manage remotely several sewer mining units thus rendering the provided service economically viable even for SMEs. The paper reports on the pilot’s overall performance and critically evaluates the potential of the sewer mining idea to become a significant piece of the circular economy puzzle for water.
H. Tyralis, G. Karakatsanis, K. Tzouka, and N. Mamassis, Data and code for the exploratory data analysis of the electrical energy demand in the time domain in Greece, Data in Brief, 13 (700-702), doi:http://dx.doi.org/10.1016/j.energy.2017.06.074, 2017.
We present data and code for visualizing the electrical energy data and weather-,climate-related and socioeconomic variables in the time domain in Greece. The electrical energy data include hourly demand, weekly-ahead forecasted values of the demand provided by the Greek Independent Power Transmission Operator and pricing values in Greece. We also present the daily temperature in Athens and the Gross Domestic Product of Greece. The code combines the data to a single report, which includes all visualizations with combinations of all variables in multiple time scales. The data and code we reused in Tyralis et al.(2017)
Full text: http://www.itia.ntua.gr/en/getfile/1825/1/documents/DataAndCode.pdf (127 KB)
G. Karakatsanis, D. Roussis, Y. Moustakis, N. Gournari, I. Parara, P. Dimitriadis, and D. Koutsoyiannis, Energy, variability and weather finance engineering, Energy Procedia, 125, 389–397, doi:10.1016/j.egypro.2017.08.073, 2017.
Weather derivatives comprise efficient financial tools for managing hydrometeorological uncertainties in various markets. With ~46% utilization by the energy industry, weather derivatives are projected to constitute a critical element for dealing with risks of low and medium impacts –contrary to standard insurance contracts that deal with extreme events. In this context, we design and engineer -via Monte Carlo pricing- a weather derivative for a remote island in Greece -powered by an autonomous diesel-fuelled generator- resembling to a standard call option contract to test the benefits for both the island’s public administration and a bank -as the transaction’s counterparty.
Full text: http://www.itia.ntua.gr/en/getfile/1734/1/documents/weather_finance_procedia.pdf (872 KB)
H. Tyralis, G. Karakatsanis, K. Tzouka, and N. Mamassis, Exploratory data analysis of the electrical energy demand in the time domain in Greece, Energy, 134 (902-918), 16 pages, doi:10.1016/j.energy.2017.06.074 0360-5442, 2017.
The electrical energy demand (EED) in Greece for the time period 2002-2016 is investigated. The aim of the study is to introduce a framework for the exploratory data analysis (EDA) of the EED in the time domain. To this end, the EED at the hourly, daily, seasonal and annual time scale along with the mean daily temperature and the Gross Domestic Product (GDP) of Greece are visualized. The forecast of the EED provided by the Greek Independent Power Transmission Operator (IPTO) is also visualized and is compared with the actual EED. Furthermore, the EED pricing system is visualized. The results of the study in general confirm and summarize the conclusions of previous relevant studies in Greece, each one treating a single topic and covering shorter and earlier time periods. Furthermore, some unexpected patterns are observed, which if not considered carefully could result to dubious models. Therefore, it is shown that the EDA of the EED in the time domain coupled with weather-, climate-related and socio-economic variables is essential for the building of a model for the short-, medium- and long-term EED forecasting, something not highlighted in the literature.
Full text: http://www.itia.ntua.gr/en/getfile/1722/1/documents/EDA_electricity_2017.pdf (3406 KB)
G. Karakatsanis, Exergy and the economic process, Energy Procedia, 97, 51–58, doi:10.1016/j.egypro.2016.10.018, 2016.
Physical work generation requires the existence of a heat gradient, according to the universal notion of the Carnot Heat Engine; also the corner stone of the exergy concept. Heat gradient availabilities fundamentally drive systems’ evolution. However, exergy is consumed irreversibly, via its gradual transformation to entropy. Extending Roegen's postulations, it is argued that exergy consumption founds economic scarcity, via: (a) human difficulty to produce large heat gradients on the Earth and (b) irreversible depletion of existing ones. Additionally, in the emerging Anthropocene epoch, exergy upgrades to a core concept for interpreting thermodynamically natural resource degradation and energy paradigm transitions.
P. Mavritsakis, A. G. Pettas, I. Tsoukalas, G. Karakatsanis, N. Mamassis, and A. Efstratiadis, A stochastic simulation framework for representing water, energy and financial fluxes across a non-connected island, European Geosciences Union General Assembly 2019, Geophysical Research Abstracts, Vol. 21, Vienna, EGU2019-8758, European Geosciences Union, 2019.
Integrated modeling of hybrid water-energy systems, comprising conventional and renewable energy sources, pumped-storage facilities and other hydraulic infrastructures, which aim to serve combined water and energy uses, is a highly challenging problem. On the one hand, such systems are subject to significant uncertainties that span over all associated input processes, physical and anthropogenic (i.e. hydrometeorological drivers and water-energy demands, respectively). On the other hand, the everyday operation of such systems is subject to multiple complexities, due to the conflicting uses, constraints and economic interests. Taking as example a future configuration of the electric system of Ikaria Island, Greece, we demonstrate a stochastic simulation framework, comprising: (a) a synthetic time series generator that reproduces the statistical and stochastic properties (i.e. marginal distributions, auto- and cross-dependencies) of all input processes, at multiple temporal scales; and (b) a simulation module employing the hourly operation of the system, to estimate the associated water, energy and financial fluxes. This scheme is used within two case studies, i.e. the optimal design of key system components, and the real-time operation of a hypothetical energy market, involving different energy providers and associated electricity sources, conventional and renewable.
G. Karakatsanis, E. Kontarakis, P. Dimitriadis, T. Iliopoulou, and D. Koutsoyiannis, Hydroclimate and agricultural output in developing countries, European Geosciences Union General Assembly 2018, Geophysical Research Abstracts, Vol. 20, Vienna, EGU2018-13059-1, European Geosciences Union, 2018.
According to international data on developing countries we observe a strong correlation of their Gross Domestic Product (GDP) to their agricultural output, suggesting that a large fraction of total income in the developing world derives from domestic agricultural value added. In addition, the significant lack of irrigation infrastructure (e.g. reservoirs and irrigation networks) forces these countries’ income into strong dependence from local hydroclimatological conditions; as the majority of crop output is -in turn- based on rain-fed agriculture. In our work we examine -via annual time-series analysis- the temporal dynamics between hydroclimate data (mainly precipitation), GDP, agricultural value added and the international prices of agricultural commodities, for developing countries, in order to study how these variables are mutually entwined in time. Furthermore, we perform various econometric tests on their correlation validity. An important aspect of our work concerns the detection of change in the composition of the economies of developing countries. Specifically, as developing countries acquire infrastructure it is highly probable to expect a gradual decoupling of the climate-agricultural output-GDP relationship.
Full text: http://www.itia.ntua.gr/en/getfile/1817/1/documents/EGU2018-13059-1.pdf (33 KB)
G.-F. Sargentis, R. Ioannidis, G. Karakatsanis, and D. Koutsoyiannis, The scale of infrastructures as a social decision. Case study: dams in Greece, European Geosciences Union General Assembly 2018, Geophysical Research Abstracts, Vol. 20, Vienna, EGU2018-17082, European Geosciences Union, 2018.
Organized societies require specific infrastructures, among which hydraulic projects are most important. Thus, for the functioning of a society, the water supply and drainage are prerequisites, while a new modern society also needs renewable energy in addition to, and in connection with, high quality water. Dams are key infrastructures in this process. Modern economic and social conditions do not define the limits of what we call "development". In this research we are mapping the limits of the development based on the capacity of the landscape, the water resources, the finances, the political aspects and the criteria of a city’s development.
S. Sigourou, P. Dimitriadis, T. Iliopoulou, R. Ioannidis, A. Skopeliti, K. Sakellari, G. Karakatsanis, L. Tsoulos, and D. Koutsoyiannis, Comparison of climate change vs. urbanization, European Geosciences Union General Assembly 2018, Geophysical Research Abstracts, Vol. 20, Vienna, EGU2018-18598-2, European Geosciences Union, 2018.
Urbanization has long been identified as one of the major human impacts on the micro-climate of urban areas and has been linked to large (and often disastrous) changes into several hydroclimatic processes such as temperature, humidity and precipitation. However, climate change studies have rarely separated the urban local-scale influence from the global one. In this study, we thoroughly investigate and compare the changes in the variability of the above hydroclimatic processes in urban regions and in the ones with small or negligible human impact. The analysis includes global historical databases of the above processes as well as of the urbanization impact through land-use change.
Full text: http://www.itia.ntua.gr/en/getfile/1810/1/documents/EGU2018-18598-2.pdf (31 KB)
S. Sigourou, P. Dimitriadis, T. Iliopoulou, R. Ioannidis, A. Skopeliti, K. Sakellari, G. Karakatsanis, L. Tsoulos, and D. Koutsoyiannis, Statistical and stochastic comparison of climate change vs. urbanization, European Geosciences Union General Assembly 2018, Geophysical Research Abstracts, Vol. 20, Vienna, EGU2018-18608-2, European Geosciences Union, 2018.
Urbanization has long been identified as one of the major human impacts on the micro-climate of urban areas and has been linked to large (and often disastrous) changes into several hydroclimatic processes such as temperature, humidity and precipitation. However, climate change studies have rarely separated the urban local-scale influence from the global one. In this study, we thoroughly investigate and compare the changes in the variability of the above hydroclimatic processes in urban regions and in the ones with small or negligible human impact. The analysis includes Monte-Carlo experiments to assess how the aforementioned variability can be simulated through a stochastic model.
Full text: http://www.itia.ntua.gr/en/getfile/1809/1/documents/EGU2018-18608-2.pdf (31 KB)
A. Gkolemis, P. Dimitriadis, G. Karakatsanis, T. Iliopoulou, and D. Koutsoyiannis, A stochastic investigation of the intermittent behaviour of wind; application to renewable energy resources management, European Geosciences Union General Assembly 2018, Geophysical Research Abstracts, Vol. 20, Vienna, EGU2018-15979-3, European Geosciences Union, 2018.
A challenging characteristic of renewable energy systems is intermittence of the related natural processes (such as wind), whose management imposes an additional cost. This also implies the need to immediate back up the extra supply (introduced by the resource’s physical bursts) to other units (e.g. in a hybrid pumped storage hydropower system). The complexity of this issue does not just rely on the need for optimizing the hybrid system but rather on the requirement for simulating these bursts. In this study, we introduce and test an innovative model for the wind process by simultaneously preserving not only the marginal distribution (including extreme events), correlation structure (from small to large scales) and internal double (diurnal and seasonal) periodicities but also its intermittent behaviour. Furthermore, we present a pilot application including a pumped storage hydropower system and we show how the additional cost imposed by the intermittent behaviour of wind can be estimated.
Full text: http://www.itia.ntua.gr/en/getfile/1795/1/documents/EGU2018-15979-3.pdf (33 KB)
G. Koudouris, P. Dimitriadis, T. Iliopoulou, G. Karakatsanis, and D. Koutsoyiannis, A stochastic model for hourly solar radiation process applied in renewable resources management, European Geosciences Union General Assembly 2018, Geophysical Research Abstracts, Vol. 20, Vienna, EGU2018-16275-2, European Geosciences Union, 2018.
Since the beginning of the 21st century, the scientific community has made huge leaps to exploit renewable energy sources, with solar radiation being one of the most important. However, the variability of solar radiation has a significant impact on solar energy conversion systems, such as in photovoltaic systems, characterized by a fast and non-linear response to incident solar radiation. The performance prediction of these systems is typically based on hourly or daily data because those are usually available at these time scales. The aim of this work is to investigate the stochastic nature and time evolution of the solar radiation process in a daily and hourly step on a monthly basis scale, with the ultimate goal of creating a stochastic model capable of generating hourly solar radiation. For this purpose, an analysis was initially made at stations in Greece and then on a global scale. We propose a distribution that can adequately describe daily solar radiation and a new distribution consisting of the sum of two known distribution functions that is capable of capturing all aspects of the hourly solar radiation. Also, we exploit the clear sky index coefficient (T) for the double periodicity of the process, so as to achieve an integrated framework for the description of the solar radiation at all scales. Also, we use statistical tests and selection criteria, in order to verify the goodness of fit of the selected distribution. Then, we propose a cyclostationary model that can handle long-term persistence and reproduce the clear sky index coefficient (KT). The model can preserve the probability density function and also the dependence structure. Finally, we apply the proposed stochastic model to a theoretical case of renewable energy management, with an ultimate goal to maximize the financial profit of the production system.
Full text: http://www.itia.ntua.gr/en/getfile/1790/1/documents/EGU2018-16275-2.pdf (32 KB)
V. Daniil, G. Pouliasis, E. Zacharopoulou, E. Demetriou, G. Manou, M. Chalakatevaki, I. Parara, C. Georganta, P. Stamou, S. Karali, E. Hadjimitsis, G. Koudouris, E. Moschos, D. Roussis, K. Papoulakos, A. Koskinas, G. Pollakis, N. Gournari, K. Sakellari, Y. Moustakis, N. Mamassis, A. Efstratiadis, H. Tyralis, P. Dimitriadis, T. Iliopoulou, G. Karakatsanis, K. Tzouka, I. Deligiannis, V. Tsoukala, P. Papanicolaou, and D. Koutsoyiannis, The uncertainty of atmospheric processes in planning a hybrid renewable energy system for a non-connected island, European Geosciences Union General Assembly 2017, Geophysical Research Abstracts, Vol. 19, Vienna, EGU2017-16781-4, doi:10.13140/RG.2.2.29610.62406, European Geosciences Union, 2017.
Non-connected islands to the electric gird are often depending on oil-fueled power plants with high unit cost. A hybrid energy system with renewable resources such as wind and solar plants could reduce this cost and also offer more environmental friendly solutions. However, atmospheric processes are characterized by high uncertainty that does not permit harvesting and utilizing full of their potential. Therefore, a more sophisticated framework that somehow incorporates this uncertainty could improve the performance of the system. In this context, we describe several stochastic and financial aspects of this framework. Particularly, we investigate the cross-correlation between several atmospheric processes and the energy demand, the possibility of mixing renewable resources with the conventional ones and in what degree of reliability, and critical financial subsystems such as weather derivatives. A pilot application of the above framework is also presented for a remote island in the Aegean Sea.
Full text: http://www.itia.ntua.gr/en/getfile/1689/1/documents/EGU2017oral_16781_final.pdf (3038 KB)
A. Koskinas, E. Zacharopoulou, G. Pouliasis, I. Engonopoulos, K. Mavroyeoryos, I. Deligiannis, G. Karakatsanis, P. Dimitriadis, T. Iliopoulou, D. Koutsoyiannis, and H. Tyralis, Simulation of electricity demand in a remote island for optimal planning of a hybrid renewable energy system, European Geosciences Union General Assembly 2017, Geophysical Research Abstracts, Vol. 19, Vienna, 19, EGU2017-10495-4, doi:10.13140/RG.2.2.10529.81767, European Geosciences Union, 2017.
We simulate the electrical energy demand in the remote island of Astypalaia. To this end we first obtain information regarding the local socioeconomic conditions and energy demand. Secondly, the available hourly demand data are analysed at various time scales (hourly, weekly, daily, seasonal). The cross-correlations between the electrical energy demand and the mean daily temperature as well as other climatic variables for the same time period are computed. Also, we investigate the cross-correlation between those climatic variables and other variables related to renewable energy resources from numerous observations around the globe in order to assess the impact of each one to a hybrid renewable energy system. An exploratory data analysis including all variables is performed with the purpose to find hidden relationships. Finally, the demand is simulated considering all the periodicities found in the analysis. The simulation time series will be used in the development of a framework for planning of a hybrid renewable energy system in Astypalaia.
D. Roussis, I. Parara, N. Gournari, Y. Moustakis, P. Dimitriadis, T. Iliopoulou, D. Koutsoyiannis, and G. Karakatsanis, Energy, variability and weather finance engineering, European Geosciences Union General Assembly 2017, Geophysical Research Abstracts, Vol. 19, Vienna, 19, EGU2017-16919, European Geosciences Union, 2017.
Most types of renewable energies are characterized by intense intermittency, causing significant instabilities to the grid; further requiring additional infrastructure (e.g. pumped-storage) for buffering hydrometeorological uncertainties, as well as complex operational rules for load balancing. In addition, most intermittent renewable units are subsidized, creating significant market inefficiencies.Weather derivatives comprise mature financial tools for integrating successfully the intermittent-load and base-load components into a unified hybrid energy system and establish their operation within a generalized uncertainty management market. With a growing global market share and 46% utilization of this financial tool by the energy industry and 12% by agriculture (that partially concerns biofuel resources), weather derivatives are projected to constitute a critical subsystem of many grids for buffering frequent hydrometeorological risks of low and medium impacts –which are not covered by standard insurance contracts that aim exclusively at extreme events and high financial damages. In this context, we study the attributes of hydrometeorological time series in a remote and small island in Greece, powered by an autonomous hybrid energy system. Upon the results we choose the optimal underlying index and we further compose and engineer a weather derivative with features of a typical option contract –which we consider most flexible and appropriate for the case– to test our assumptions on its beneficiary effects for both the budget of private energy producers and the island’s public administration.
G. Karakatsanis, and S. Bierbach, Entropy of Egypt’s virtual water trade gravity field, European Geosciences Union General Assembly 2016, Geophysical Research Abstracts, Vol. 18, Vienna, EGU2016-14763-3, European Geosciences Union, 2016.
The study investigates the entropy of Egypt's virtual water trade gravity distribution, in order to provide a chart of Egypt's embodied water balance in agricultural trade, in relation to distances with its major counterparties. Moreover, our calculations on the amount of the embodied water traded between Egypt and each of its partners take place according to a combination of available data on the blue, green and grey water footprints as well as the Food and Agriculture Organization (FAO) database of traded amounts per crop type. A study on the virtual water trade gravity, enables us to enrich former related studies (Fracasso 2014; Fracasso, Sartori and Schiavo 2014) via examining Egypt's water supply dependence on the Nile River and if comparative advantages -purely from the side of water quantities- can be identified via recognizing which water footprint categories are particularly high. Additionally, this methodology can comprise -from a fundamental level- a guide for revealing the importance of water footprint types for Egypt's agricultural sector; hence, Egypt's potential comparative advantages, as far as quantitative water endowments are exclusively concerned (without consideration of water or crop prices). Although it is pointed out very correctly by various authors (Antonelli and Sartori 2014) that the virtual water trade concept does not incorporate many important aspects of water supply -such as heavy water price subsidizing- to be used accurately for the identification of comparative advantages, we consider that the purely quantitative examination can provide strong fundamental indications -especially for green and grey water footprints, which are hypothesized to be less sensitive to subsidizing. In overall, this effect can very well provide a primary indication on the organization of the global alimentation trade network (Yang et al. 2006). The gravity equation used contains water footprint data for the 15 top traded crops and the distances for Egypt's 20 trading partner countries, for a time frame from 1995 to 2013. The calculations -implemented for each country and each crop- display a network that illustrates the gravity of virtual water trade. It is then possible for us to model the entropy of Egypt's virtual water trade gravity field, via the statistical examination of its spatial fragmentation or continuity for each traded crop and for each water footprint type. Hence, with the distribution's entropy we may conduct a targeted analysis on the comparative advantages of the Egyptian agriculture.
M. Malik, Z. Nisar, and G. Karakatsanis, Socioeconomic dynamics of water quality in the Egyptian Nile, European Geosciences Union General Assembly 2016, Geophysical Research Abstracts, Vol. 18, Vienna, EGU2016-17104, European Geosciences Union, 2016.
The Nile River remains the most important source of freshwater for Egypt as it accounts for nearly all of the country’s drinking and irrigation water. About 95% of the total population is accounted to live along the Banks of the Nile. Therefore, water quality deterioration in addition to general natural scarcity of water in the region is the main driver for carrying out this study. What further aggravates this issue is the water conflict in the Blue Nile region. The study evaluates different water quality parameters and their concentrations in the Egyptian Nile; further assessing the temporal dynamics of water quality in the area with (a) the Environmental Kuznets Curve (EKC) and (b) the Jevons Paradox (JP) in order to identify water quality improvements or degradations using selected socioeconomic variables. For this purpose various environmental indicators including BOD, COD, DO, Phosphorus and TDS were plotted against different economic variables including Population, Gross Domestic Product (GDP), Annual Fresh Water Withdrawal and Improved Water Source. Mathematically, this was expressed by 2nd and 3rd degree polynomial regressions generating the EKC and JP respectively. The basic goal of the regression analysis is to model and highlight the dynamic trend of water quality indicators in relation to their established permissible limits, which will allow the identification of optimal future water quality policies. The results clearly indicate that the dependency of water quality indicators on socioeconomic variables differs for every indicator; while COD was above the permissible limits in all the cases despite of its decreasing trend in each case, BOD and phosphate signified increasing concentrations for the future, if they continue to follow the present trend. This could be an indication of rebound effect explained by the Jevons Paradox i.e. water quality deterioration after its improvement, either due to increase of population or intensification of economic activities related to these indicators.
G. Karakatsanis, Energy and the capital of nations, European Geosciences Union General Assembly 2016, Geophysical Research Abstracts, Vol. 18, Vienna, EGU2016-18530-1, European Geosciences Union, 2016.
The economically useful time of fossil fuels in Earth is estimated in just ∼160 years, while humanity itself counts ∼150*10ˆ3 years. Within only ∼0,15% of this time, humanity has used more energy, accumulating so much wealth than within the rest of its existence time. According to this perspective, the availability of heat gradients is what fundamentally drives the evolution of economic systems, via the extensive enhancement –or even substitution-of human labor (Ayres and Warr 2009). In the modern industrial civilization it is estimated (Kümmel 2011) that the average human ability to generate wealth (productivity) has increased by ∼40%-50% –including the effects from the growth of human population- further augmented by significant economies of scale achieved in the industrial era. This process led to significant accumulation of surpluses that generally have the form of capital. Although capital is frequently confused with the stock of mechanical equipment, capital can be generalized as any form of accumulated (not currently consumed) production factor that can deliver a benefit in the future. In that sense, capital is found in various forms, such as machinery, technology or natural resources and environmental capacities. While it is expected that anthropogenic forms of capital are accumulated along the increase of energy use, natural capital should be declining, due to the validity of the Second Law of Thermodynamics (2nd Law), entropy production and –in turn- the irreversible (monotonic) consumption of exergy (Wall 2005). Regressions of the LINear EXponential (LINEX) function (an economic growth function depending linearly on energy and exponentially on output elasticity quotients) (Lindenbeger and Kummel 2011) for a number of industrialized economies -like the USA, Germany and Japan, found that output elasticities were highest for energy (except for US where it was second highest after capital); meaning that in industrial economies, energy comprises the most significant production factor. This work enriches such studies via integrating the analysis all forms of capital and for a wider range of countries; estimating the trade-off –as output elasticity ratios- between the accumulation of various anthropogenic capital forms and the deterioration of natural capital –considered both as resource stock and carrying capacities of the environment.
G. Karakatsanis, Exergy and the economic process, European Geosciences Union General Assembly 2016, Geophysical Research Abstracts, Vol. 18, Vienna, European Geosciences Union, 2016.
The Second Law of Thermodynamics (2nd Law) dictates that the introduction of physical work in a system requires the existence of a heat gradient, according to the universal notion of Carnot Heat Engine. This is the corner stone for the notion of exergy as well, as exergy is actually the potential of physical work generation across the process of equilibration of a number of unified systems with different thermodynamic states. However, although energy concerns the abstract ability of work generation, exergy concerns the specific ability of work generation, due to the requirement for specifying an environment of reference, in relation to which the thermodynamic equilibration takes place; also determining heat engine efficiencies. Consequently, while energy is always conserved, exergy -deriving from heat gradient equilibration- is always consumed. According to this perspective, the availability of heat gradients is what fundamentally drives the evolution of econosystems, via enhancing -or even substituting- human labor (Boulding 1978; Chen 2005; Ayres and Warr 2009). In addition, exergy consumption is irreversible, via the gradual transformation of useful physical work to entropy; hence reducing its future economic availability. By extending Roegen's relative approach (1971), it could be postulated that this irreversible exhaustion of exergy comprises the fundamental cause of economic scarcity, which is the corner stone for the development of economic science. Conclusively, scarcity consists in: (a) the difficulty of allocating -in the Earth System- very high heat gradients that would make humanity's heat engines very efficient and (b) the irreversible depletion of existent heat gradients due to entropy production. In addition, the concept of exergy could be used to study natural resource degradation and pollution at the biogeochemical level and understand why heat gradient scarcity in the Earth System was eventually inevitable. All of these issues are analyzed both theoretically and quantitatively.
Full text: http://www.itia.ntua.gr/en/getfile/1856/1/documents/EGU_2016_GK_18476.pdf (3812 KB)
G. Karakatsanis, Energy and the agroeconomic complexity of Ethiopia, European Geosciences Union General Assembly 2016, Geophysical Research Abstracts, Vol. 18, Vienna, European Geosciences Union, 2016.
Since the Industrial Revolution, modern agriculture has transformed from a net energy supplier to a net energy user, via the extensive use fossil fuels -that substituted solar energy inputs- and petroleum derivative products (fertilizers) (Pimentel and Pimentel 2008; Woods et al. 2010). This condenses a significant overview of agricultural energetics, especially for economies set on their first stage of development, growth and economic diversification, such as Ethiopia. Ethiopia is the Blue Nile's most upstream country, constituting a very sensitive hydroclimatic area. Since 2008, Ethiopian agriculture experiences a boost in energy use and agricultural value-added per worker, due to the rapid introduction of oil-fueled agricultural machinery that increased productivity and allowed crop diversification. Agriculture in Ethiopia accounts for ~82% of its total exports, ~45% of its Gross Domestic Product (GDP) and ~75% of its total labor force. In addition, Ethiopia's agricultural sector is equipped with a set of new financial tools to deal with hydroclimatic extremes, like the 1983-85 droughts that deteriorated its crop output, causing a devastating famine. In fact, Ethiopia's resilience from the (most) recent drought (2015-16) has been remarkable. These facts signify that Ethiopia satisfies the necessary conditions to become a regional agritrade gravity center in the Blue Nile, granted that the dispersion of agricultural trade comprises a primary tool for securing food supply. As gravity equations have been used to model global trade webs (Tinbergen 1962), similar principles may apply to agritrade as well, for identifying emergent topological structures and supply chains. By examining the relation between energy inputs in agriculture with crop diversification and value-added chains of Ethiopia's agritrade, we could extract accurate information on the importance of energy for the country's agroeconomic complexity and regionalization trend across its first stages of development. Via the use of entropy we may identify patterns of agritrade agglomeration or dispersal; alternatively study the continuity or fragmentation of Ethiopia's agritrade gravity field. Agglomeration towards Ethiopian agricultural supply would indicate the upgrade of the country's supply stability and -therefore- importance in the global agritrade web.
G. Karakatsanis, H. Tyralis, and K. Tzouka, Entropy, pricing and productivity of pumped-storage, European Geosciences Union General Assembly 2016, Geophysical Research Abstracts, Vol. 18, Vienna, European Geosciences Union, 2016.
Pumped-storage constitutes today a mature method of bulk electricity storage in the form of hydropower. This bulk electricity storability upgrades the economic value of hydropower as it may mitigate -or even neutralize- stochastic effects deriving from various geophysical and socioeconomic factors, which produce numerous load balance inefficiencies due to increased uncertainty. Pumped-storage further holds a key role for unifying intermittent renewable (i.e. wind, solar) units with controllable non-renewable (i.e. nuclear, coal) fuel electricity generation plants into integrated energy systems. We develop a set of indicators for the measurement of performance of pumped-storage, in terms of the latter's energy and financial contribution to the energy system. More specifically, we use the concept of entropy in order to examine: (1) the statistical features -and correlations- of the energy system's intermittent components and (2) the statistical features of electricity demand prediction deviations. In this way, the macroeconomics of pumped-storage emerges naturally from its statistical features (Karakatsanis et al. 2014). In addition, these findings are combined to actual daily loads. Hence, not only the amount of energy harvested from the pumped-storage component is expected to be important, but the harvesting time as well, as the intraday price of electricity varies significantly. Additionally, the structure of the pumped-storage market proves to be a significant factor as well for the system's energy and financial performance (Paine et al. 2014). According to the above, we aim at postulating a set of general rules on the productivity of pumped-storage for (integrated) energy systems.
Full text: http://www.itia.ntua.gr/en/getfile/1854/1/documents/EGU_2016_GK_15481.pdf (3409 KB)
H. Tyralis, G. Karakatsanis, K. Tzouka, and N. Mamassis, Analysis of the electricity demand of Greece for optimal planning of a large-scale hybrid renewable energy system, European Geosciences Union General Assembly 2015, Geophysical Research Abstracts, Vol. 17, Vienna, EGU2015-5643, European Geosciences Union, 2015.
The Greek electricity system is examined for the period 2002-2014. The demand load data are analysed at various time scales (hourly, daily, seasonal and annual) and they are related to the mean daily temperature and the gross domestic product (GDP) of Greece for the same time period. The prediction of energy demand, a product of the Greek Independent Power Transmission Operator, is also compared with the demand load. Interesting results about the change of the electricity demand scheme after the year 2010 are derived. This change is related to the decrease of the GDP, during the period 2010-2014. The results of the analysis will be used in the development of an energy forecasting system which will be a part of a framework for optimal planning of a large-scale hybrid renewable energy system in which hydropower plays the dominant role.
G. Karakatsanis, Entropy, pumped-storage and energy system finance, European Geosciences Union General Assembly 2015, Geophysical Research Abstracts, Vol. 17, Vienna, EGU2015-11759, European Geosciences Union, 2015.
Pumped-storage holds a key role for integrating renewable energy units with non-renewable fuel plants into large-scale energy systems of electricity output. An emerging issue is the development of financial engineering models with physical basis to systematically fund energy system efficiency improvements across its operation. A fundamental physically-based economic concept is the Scarcity Rent; which concerns the pricing of a natural resource’s scarcity. Specifically, the scarcity rent comprises a fraction of a depleting resource’s full price and accumulates to fund its more efficient future use. In an integrated energy system, scarcity rents derive from various resources and can be deposited to a pooled fund to finance the energy system’s overall efficiency increase; allowing it to benefit from economies of scale. With pumped-storage incorporated to the system, water upgrades to a hub resource, in which the scarcity rents of all connected energy sources are denominated to. However, as available water for electricity generation or storage is also limited, a scarcity rent upon it is also imposed. It is suggested that scarcity rent generation is reducible to three (3) main factors, incorporating uncertainty: (1) water’s natural renewability, (2) the energy system’s intermittent components and (3) base-load prediction deviations from actual loads. For that purpose, the concept of entropy is used in order to measure the energy system’s overall uncertainty; hence pumped-storage intensity requirements and generated water scarcity rents.
Full text: http://www.itia.ntua.gr/en/getfile/1528/1/documents/EGU2015-11759-2.pdf (35 KB)
A. Koukouvinos, D. Nikolopoulos, A. Efstratiadis, A. Tegos, E. Rozos, S.M. Papalexiou, P. Dimitriadis, Y. Markonis, P. Kossieris, H. Tyralis, G. Karakatsanis, K. Tzouka, A. Christofides, G. Karavokiros, A. Siskos, N. Mamassis, and D. Koutsoyiannis, Integrated water and renewable energy management: the Acheloos-Peneios region case study, European Geosciences Union General Assembly 2015, Geophysical Research Abstracts, Vol. 17, Vienna, EGU2015-4912, doi:10.13140/RG.2.2.17726.69440, European Geosciences Union, 2015.
Within the ongoing research project “Combined Renewable Systems for Sustainable Energy Development” (CRESSENDO), we have developed a novel stochastic simulation framework for optimal planning and management of large-scale hybrid renewable energy systems, in which hydropower plays the dominant role. The methodology and associated computer tools are tested in two major adjacent river basins in Greece (Acheloos, Peneios) extending over 15 500 km2 (12% of Greek territory). River Acheloos is characterized by very high runoff and holds ~40% of the installed hydropower capacity of Greece. On the other hand, the Thessaly plain drained by Peneios – a key agricultural region for the national economy – usually suffers from water scarcity and systematic environmental degradation. The two basins are interconnected through diversion projects, existing and planned, thus formulating a unique large-scale hydrosystem whose future has been the subject of a great controversy. The study area is viewed as a hypothetically closed, energy-autonomous, system, in order to evaluate the perspectives for sustainable development of its water and energy resources. In this context we seek an efficient configuration of the necessary hydraulic and renewable energy projects through integrated modelling of the water and energy balance. We investigate several scenarios of energy demand for domestic, industrial and agricultural use, assuming that part of the demand is fulfilled via wind and solar energy, while the excess or deficit of energy is regulated through large hydroelectric works that are equipped with pumping storage facilities. The overall goal is to examine under which conditions a fully renewable energy system can be technically and economically viable for such large spatial scale.
Other works that reference this work (this list might be obsolete):
|1.||Stamou, A. T., and P. Rutschmann, Pareto optimization of water resources using the nexus approach, Water Resources Management, 32, 5053-5065, doi:10.1007/s11269-018-2127-x, 2018.|
|2.||Stamou, A.-T., and P. Rutschmann, Optimization of water use based on the water-energy-food nexus concept: Application to the long-term development scenario of the Upper Blue Nile River, Water Utility Journal, 25, 1-13, 2020.|
G. Karakatsanis, N. Mamassis, and D. Koutsoyiannis, Entropy, recycling and macroeconomics of water resources, European Geosciences Union General Assembly 2014, Geophysical Research Abstracts, Vol. 16, Vienna, European Geosciences Union, 2014.
We develop a macroeconomic model of water quantity and quality supply multipliers derived from water recycling (Karakatsanis et al. 2013) and examine its statistical properties. Macroeconomic models that incorporate natural resource conservation have become increasingly important (European Commission et al. 2012) for national accounting. In addition, as an estimated 80% of globally used freshwater is not reused (United Nations 2012), with increasing population trends, water resource recycling becomes a solution of high priority. Recycling of water resources generates two major conservation effects: (1) conservation of water in reservoirs and aquifers and (2) conservation of ecosystem carrying capacity due to wastewater flux reduction. It is the properties of the distribution of recycling efficiencies –on quantity and quality- per sector that determine macroeconomic decoupling from geophysical uncertainty. Generally, uncertainty may statistically be quantified by entropy. Higher entropy signifies a greater dispersion of recycling efficiencies and potentially greater exposure to geophysical uncertainty; probably indicating the need for additional infrastructure for the statistical distribution’s both shifting and concentration towards higher efficiencies, supply multipliers and geophysical uncertainty decoupling.
G. Karakatsanis, N. Mamassis, D. Koutsoyiannis, and A. Efstratiadis, Entropy, pricing and macroeconomics of pumped-storage systems, European Geosciences Union General Assembly 2014, Geophysical Research Abstracts, Vol. 16, Vienna, EGU2014-15858-6, European Geosciences Union, 2014.
We propose a pricing scheme for the enhancement of macroeconomic performance of pumped-storage systems, based on the statistical properties of both geophysical and economic variables. The main argument consists in the need of a context of economic values concerning the hub energy resource; defined as the resource that comprises the reference energy currency for all involved renewable energy sources (RES) and discounts all related uncertainty. In the case of pumped-storage systems the hub resource is the reservoir’s water, as a benchmark for all connected intermittent RES. The uncertainty of all involved natural and economic processes is statistically quantifiable by entropy. It is the relation between the entropies of all involved RES that shapes the macroeconomic state of the integrated pumped-storage system. Consequently, there must be consideration on the entropy of wind, solar and precipitation patterns, as well as on the entropy of economic processes –such as demand preferences on either current energy use or storage for future availability. For pumped-storage macroeconomics, a price on the reservoir’s capacity scarcity should also be imposed in order to shape a pricing field with upper and lower limits for the long-term stability of the pricing range and positive net energy benefits, which is the primary issue of the generalized deployment of pumped-storage technology.
G. Karakatsanis, N. Mamassis, D. Koutsoyiannis, and A. Efstratiadis, Entropy and reliability of water use via a statistical approach of scarcity, Facets of Uncertainty: 5th EGU Leonardo Conference – Hydrofractals 2013 – STAHY 2013, Kos Island, Greece, doi:10.13140/RG.2.2.24450.68809, European Geosciences Union, International Association of Hydrological Sciences, International Union of Geodesy and Geophysics, 2013.
The paper examines economic reliability of water resource availability within a stochastic framework. Hoekstra and Mekonnen (2012) provide water use data for agricultural and industrial production. The current work utilizes these findings by coupling hydrological processes with reliability for economic use via a statistical approach of scarcity. Water extracted from the hydrological cycle is never bounded permanently, but only creates temporary scarcity via the competitive use of its limited economically useful attributes (such as its quality). The replenishment rate of freshwater reservoirs is limited and the return of water to its natural path requires energy inputs and time. Hence, what the economy is actually deprived of via the intensification of water use, the diversion of a water resource from its natural hydrological path and the eventual degradation after its use is its immediate availability, which is equivalent to increased uncertainty as the economy reaches closer to its natural water supply reliability limit. Georgescu-Roegen (1986) postulated a connection between increased dispersion and supply uncertainty of a resource to entropy, which in the case of water might be interpreted as increase of the probability of temporal unavailability.
Full text: http://www.itia.ntua.gr/en/getfile/1389/1/documents/Kos_Karakatsanis.pdf (736 KB)
G. Karakatsanis, I. Apostolopoulos, G. Alexiou, P. Stamouli, I. Fountoulakis, S. C. Batelis, Y. Dimakos, E. Feloni, E. C. Moschou, N. Bountas, N. Boboti, D. Bouziotas, P. Dimas, and E. Sepetzi, Water resources, infrastructures and services: Privatization or municipalization?, Athens, 4 July 2013.
Student Workshop of the course "Water Resources Management". Coordinators: Demetris Koutsoyiannis & Andreas Efstratiadis
Photos from the workshop are also available. Extensive reportage of the event was presented by the newspaper Eleftherotypia, (see also the print version in an attached file above), as well as by Internet forums (e.g. Econews, Infowar).