George Xydis

Aarhus University

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

Evanthia A. Nanaki

Aarhus University

C. Koroneos

University of Western Macedonia

Peter Enevoldsen

Aarhus University

Dafni Despoina Avgoustaki

Agricultural University of Athens

A. L. Polyzakis

University of Peloponnese

A. Sotiropoulos

National Technical University of Athens

ΑE

Αspasia Efthimiadou

Agricultural University of Athens

Anna-Katharina von Krauland

Stanford University

Benjamin K. Sovacool

Aarhus University

Orhan Altuğ Karabiber

Aarhus University

Cooperative Institutions

Aarhus University

Universidade Federal do Espírito Santo

Johns Hopkins University

National Technical University of Athens

Technical University of Denmark

Universidad Politécnica de Madrid

Technological Educational Institute of Piraeus

Aristotle University of Thessaloniki

Agricultural University of Athens

Centre for Research and Technology Hellas

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Applying AI-Based Solutions to Avoid Bird Collisions at Wind Parks

Springer proceedings in energy (2020)

Eldina Salkanović Peter Enevoldsen George Xydis

10.1007/978-3-030-38804-1_7

Cite

Citations (6)

Autonomous Mobile Robot with Attached Multispectral Camera to Monitor the Development of Crops and Detect Nutrient and Water Deficiencies in Vertical Farms

Agronomy (2022)

Dafni Despoina Avgoustaki Ioannis Avgoustakis Carlos Corchado Miralles Jonas Sohn George Xydis

This study demonstrates the potential of using low-altitude multispectral imagery data to assess irrigation and fertilization techniques and the relative degree of plant water and nutrient stress. This study aims to create a methodology that can be widely used by vertical farms. Techniques were used for early water and nitrogen stress detection using multispectral reflectance systems in an indoor environment with artificial lighting. The methodology focuses on irrigation and nutrition, that sets schedules, and automatically updates a decision-making system based on crop reflectance data and simplified reflectance indices. The experimental process took place on the premises of CphFarmHouse in Denmark. The results showed that crop reflectance increased due to water and nitrogen deficiencies. The detected reflectance increase was significant on the third day of the experiment when irrigation and fertilization were not applied. It should be noted that during the experimental period, the researchers did not detect water or nitrogen deficiencies visible to the naked eye. More specifically, the Normalized Difference Vegetation Index (NDVI) and the Photochemical Reflectance Index (PRI) showed statistically significant differences between the control treatment and the two stress treatments with limited water and nitrogen. Additionally, based on the reflectance measurements and the measured physiological crop parameters, significant correlations (p < 0.01) were observed mainly between the PRI and the chlorophyll content, the photosynthetic efficiency and the stomatal conductance (r = 0.84/0.90, 0.73/0.66, 0.61/0.66 among the nitrogen and water treatments). The research provides data analysis results on sensors and approaches for crop reflectance measurements as well as spectral indices for remote water and nitrogen detection. Finally, the results provide a feasibility analysis, suggesting that multispectral images could be used as a rapid tool to estimate the physiological status of plants, which is indicative of the spatial variation in the vertical farm.

Photochemical Reflectance Index

Stomatal Conductance

10.3390/agronomy12112691

Cite

Citations (11)

Environmental impact assessment of electricity production from lignite

Environmental Progress & Sustainable Energy (2016)

Evanthia A. Nanaki C. Koroneos George Xydis

Lignite is by far the most used fuel in Greece for the production of electricity as there are large reserves in the country. The high emissions of global warming gases have led to the need for the adaptation of measures and initiatives to reduce emissions in the Greek energy system for the period up to 2030. It is imperative that an environmental policy and measures are implemented to limit CO 2 emissions towards the Kyoto targets. The objective of this work is to analyze the environmental impacts associated with the atmospheric emissions and other wastes that are produced during the extraction, transportation, and use of lignite for electricity production in Greece using the methodology of life cycle assessment. The results presented here indicate that the most significant emission's reduction can be made from technology substitution. The introduction of advanced fossil fuel technologies can also lead to improvements in life‐cycle GHG emissions. NOx, SO 2 , and PM emissions from the lignite life cycle, contributing to the respiratory effects impact category (21.1–28.3%), have a bigger impact than the climate change (10–32.7%) and acidification/eutrophication effects (2.17–3.82%). As per Greece's National Renewable Energy Policy the penetration of renewable energy sources in country's energy mix is investigated. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1868–1875, 2016

10.1002/ep.12427

Cite

Citations (10)

Results on the implementation of an innovative dehydrated biological waste to ethanol management scheme

International Journal of Environmental Science and Technology (2018)

A. Sotiropoulos George Xydis Nikoleta Kontogianni Stergios Vakalis

Hemicellulose

10.1007/s13762-018-2135-7

Cite

Citations (2)

Energy demand analysis via small scale hydroponic systems in suburban areas – An integrated energy-food nexus solution

The Science of The Total Environment (2017)

George Xydis Stelios Liaros Konstantinos Botsis

energy demand

Food energy

10.1016/j.scitotenv.2017.03.170

Cite

Citations (33)

Wind energy in the Gulf Cooperation Council region: progress, challenges and strategies for development

Review of Economics and Political Science (2021)

Colby Connelly George Xydis

Purpose Until recently, the Gulf Cooperation Council (GCC) region, whose members consist of Saudi Arabia, the United Arab Emirates, Kuwait, Qatar, Oman and Bahrain, has not significantly focused on the green transition. Specifically, wind energy development has made minimal progress relative to that of other regions. Design/methodology/approach The abundance of cheap fossil fuels in the region has not incentivized renewable energy development, and where this has taken place solar technologies are often preferred. Findings However, lower technology costs together with lost investment opportunities – also common elsewhere in the world, has increased the pressure on the GCC region from developers. This work qualitatively addresses the challenges and the strategies for the wind development in the area. It focuses on the analysis of different proposed type of investments – driven by a state-supported proposed fund – such as utility-scale investments, industry-specific investments, manufacturing investments and regional accelerators. Originality/value The work also suggests that Gulf sovereign wealth funds should act as the lead investors under new schemes, such as joint ventures, for wind development in the GCC, using their wealth to offering their populations with new sources of employment as well as energy that is sustainable.

Investment

10.1108/reps-12-2020-0183

Cite

Citations (7)

Long-term heat storage opportunities of renewable energy for district heating networks

Proceedings of the Institution of Civil Engineers - Energy (2023)

Kristian Emil Schrøder Hansen George Xydis

This study compares different thermal heat storage solutions existing in the market, fuelled with energy from different renewable energy sources with a focus on integrating thermal heat storage into the district heating grid. The paper is based on a case in the municipality of Silkeborg, Denmark, which has the largest solar thermal panel plant in Northern Europe. A theoretical approach was used to compare with assumed excess power from wind and solar in the DK1 area, with Silkeborg's allocated excess power at 0.01%. This yielded overall efficiencies between η = 0.739–0.765 and η = 0.864–0.895 for the Silkeborg solar thermal plant. Four different thermal heat storage solutions were compared: tank thermal energy storage, pit energy storage, aquifer thermal energy storage and borehole energy storage (BTES). The analysis showed that, of the four solutions compared, BTES was the best for storing thermal energy for a longer period of time, with the lowest heat loss rate of 0.6% and the highest efficiency of up to 89.5%. However, some complications make it difficult to establish a BTES storage solution, since it is very much dependent on earth conditions and initial capital.

Renewable heat

Thermal energy

Capital cost

10.1680/jener.23.00023

Cite

Citations (1)

Electric vehicle deployment in urban areas

Indoor and Built Environment (2015)

Evanthia A. Nanaki George Xydis C. Koroneos

The transportation sector accounts for approximately one-fifth of global primary energy use and one quarter of all energy related carbon dioxide emissions, with nearly half of those emissions originating from passenger vehicles. In order to reduce significantly the use of fossil fuels in urban mobility, whilst improving air quality and increasing the accessibility and attractiveness of urban areas, it is necessary to increase the use of non-conventionally fuelled vehicles for passenger and freight transport in urban areas. The introduction of electric vehicles (EVs) is a promising option, so as to achieve decarbonisation objectives, energy security, improved urban air quality and to increase energy efficiency. However, there are a number of challenges for the large-scale deployment of EV both on global and European level. These, in particular, are the high cost of the battery, lack of a standardised recharging infrastructure, relatively low range of battery electric vehicles or lack of interesting value proposition for consumers. A few studies have attempted to calculate the costs and benefits of EVs, but none consider the cost and benefits of EVs at a level of detail comparable to what has been performed for other vehicle technologies. This study constructs the Total Cost of Ownership (TCO) of EVs, based on real data from the auto-industry, in order to assess the costs and benefits as well as the potentiality of electro-mobility deployment in urban areas.

Energy Security

Driving range

Value proposition

10.1177/1420326x15623078

Cite

Citations (12)

How much wind power potential does europe have? Examining european wind power potential with an enhanced socio-technical atlas

Energy Policy (2019)

Peter Enevoldsen Finn-Hendrik Permien Inès Bakhtaoui Anna-Katharina von Krauland Mark Z. Jacobson

Sea breeze

Spatial Planning

10.1016/j.enpol.2019.06.064

Cite

Citations (108)

Are only demand-based policy incentives enough to deploy electromobility?

Policy Studies (2020)

Evanthia A. Nanaki Spyros Kiartzis George Xydis

European Union (EU)'s energy and policy targets necessitate the penetration of new propulsion systems in the automotive industry. In this direction, the deployment of electric vehicles (EVs) and plug-in hybrid electric vehicles that rely on low greenhouse gas emission electricity generation has great potential to significantly alleviate the dependence on fossil fuel consumption in the transport sector. In this study, the policy incentives that different countries have implemented for stimulating the market of EVs are presented. Different policy instruments are examined, in order to support the deployment of EVs in Greece. Based on data from previous study, where total costs of ownership have been calculated, three alternative policy support incentives have been developed and analysed to promote the use of EVs until 2030 in Greece. Results indicate the direct subsidy scheme is more favourable over a carbon taxation system. It is suggested that EV will be competitive with ICE in the year 2022/2023, if no additional policies are implemented in Greece. This study fills the gap in the literature by offering a policy view of the main measures as well of actions that need to be taken in Greece, in order to promote electromobility.

Market Penetration

Consumption

10.1080/01442872.2020.1718072

Cite

Citations (9)