Sustainable island power system – Scenario analysis for Crete under the energy trilemma index

Sustainable energy supply is an essential part for economic and social development in every society. Islands as geographical isolated regions have to confront a number of challenges to secure a reliable and clean energy system. Currently, electricity demand on the Greek island of Crete is supplied by oil-fired engines imposed to new emissions restrictions applied from 2020. Thus, a capacity upgrade is necessary and new solutions driven by renewable energy, energy storage and interconnections. This study investigates three scenarios: Business as Usual (BAU); Natural Gas (NG); and the Interconnection of Crete with the National Grid System (Int.) to assess the potential techno-economic and environmental impact of the required transition under the Energy Trilemma Index. A capacity expansion and operation optimisation process has been applied through a high resolution spatio-temporal analysis performed with PLEXOS Integrated Energy Model. It was concluded that no BAU Scenario could facilitate a future plan for the electricity system of Crete or any European island imposed to such constrains. The optimum scenario incorporates interconnectors and energy storage systems that manage to deliver 52% reduction in the total system costs (2020-2040), 79% in electricity prices and 48% reduction in GHG emissions by 2040, compared to the BAU

Past trends for the UK Energy Scenarios: How close are their predictions to reality?

This study provides an exploration of the future energy trends in the UK by assessing existing energy scenarios studies and their predictions compared with actual data. The criteria for inclusion were to be national in scope, backcasting and comprehensive (covering the electricity sector). The importance of assessing the historic energy system projections could conduct us to improvements in future energy scenarios. The three studies considered relate to the same four factors: growth indicators, fuel prices, new installations and power stations retirement. The scenarios review revealed several common and different themes although all were developed under the same national targets

Modelling electrical interconnections for Rhodes island power system

Remote island power systems often fail to enjoy the right to secure, clean energy supply. This paper presents a short-term analysis for the electrical system of Rhodes-Halki in South Aegean, with the use of a mixed-integer dispatch module in PLEXOS® Simulation Software. While examining the impact of submarine grid extensions, the results show that following the interconnection of Rhodes' power system, rapid renewable energy deployment is recorded, allowing for electricity exports equal to 220 MWh by 2040. Power generation costs decline by 58.9% for the week recording MAX demand and 54.8% for the week recording MIN demand, compared to the BAU autonomous scenario. The scenario imposing generation restrictions according to directives 2010/75/EU and 2015/2193/EU shows high levels of unserved hourly energy equal to 70%-85%

Long Term analysis of submarine transmission grid extensions between the Greek islands and the mainland

Interconnections' infrastructure is considered fundamental to implement the common rules for the internal electricity market according to 2009/72/EU. Greece currently consists of 29 non-interconnected island systems, experiencing frequent forced outages and high generation costs. A number of interconnection plans are in the pipeline between the Greek islands in the Aegean Sea archipelago and the Greek bulk continental grid. This paper investigates interconnection scenarios and their impact in terms of security of supply, costs and renewable energy integration into the system. PLEXOS® Simulation Software by Energy Exemplar is used to simulate the Greek electricity system. The results show a twofold growth of renewables share between 2020 and 2040 while electricity generation costs recorded on the non-interconnected islands mirror continental costs following the grid extensions. Loss of load probability and unserved energy are eliminated, whilst greenhouse gas emissions are reduced by 73% (vs 1990) in 2040

An analysis of the impact of bioenergy and geosequestration in the UK future energy system

Three different energy scenarios have been considered to analyse the impact of bioenergy and geosequestration to GHG emissions in the UK for 2050. The analysis was accomplished with the use of the DECC 2050 Pathways Calculator. The outcomes focused on energy demand and supply and GHG emissions. The results showed that bioenergy and geosequestration are key factors for a low carbon energy system as they are capable of reducing significanlty carbon emissions, in parallel with the deployment of other clean energy techlogies

Wind offshore energy in the Northern Aegean Sea islanding region

The Greek state estimated a potential of 1,500 MW wind offshore capacity, which can be exploited by 2020, while 943.15 MW are located in the Northern Aegean Sea islanding region. This study presents a techno-economic assessment of wind offshore energy in the Northern Aegean Sea. Different topologies are proposed, taking into account wind offshore and islands interconnections using HVDC and HVAC technology. Investment indicators are based on the expected power generated by the Weibull wind speed probability density function and the total investment cost required for wind offshore engineering. The results show that the two wind offshore farms can secure the complete electrification of the neighboring islands and supply approximately 3,379 GWh to the main consumption centers in northern and central Greece on an annual basis. A sensitivity analysis towards investment optimization has been performed, proposing different wind turbine technologies and interconnection scenarios

Transforming the Greek Cycladic islands into a wind energy hub

The interconnection of the Greek Cyclades islands with the mainland national grid system is scheduled to be completed by 2025. The aim of this project is to improve energy security, reduce costs and carbon dioxide emissions and increase the use of renewable energy resources. Enhancement of the current isolated power networks through interconnectors will allow higher integration of intermittent wind energy loads to the system. This paper analyses an action plan alongside its economic and carbon dioxide emissions impact, between 2017 and 2030, for the implementation of 258·6 MW wind farms in the region, the equivalent of 772·5 GWh/year according to the Weibull wind speed distribution analysis. The estimated average investment return rate for wind projects equals 23%. This is calculated using a life cycle cost analysis. The average cost of energy by using the International Energy Agency methodology equals €80·9/MWh. This paper concludes that the Cyclades interconnection will assist in transforming the region into a wind energy hub, with zero carbon dioxide emissions, allowing electricity exports of 101 GWh/year to the Greek mainland, while reducing the total electricity costs by €1·4 billion from 2017 to 2030

Potential economic and environmental benefits from the interconnection of the Greek islands

Greece consists of 58 non-interconnected islands, located mainly in the Aegean Sea. Electricity is supplied to this region by 32 autonomous power systems (APS) using heavy fuel oil or diesel power generators. A number of interconnections between the islands and the national grid system have been scheduled for the upcoming years. In this paper, we analyse the economic and environmental benefits following the interconnections. It was concluded that Greece could save between 2015 and 2040, from 9.73 to 17.82 billion Euros, subject to fuel price costs and demand growth. These amounts are charged to the Greek power customers through a cross subsidisation policy known as public service obligation. Additionally, avoided costs for APS upgrade, range between 2.63 and 1.80 billion Euros. Interconnectors will also reduce the carbon footprint in the area by 51.1%–65.5% compared to the scenario of preserving APS. This is attributed mainly to renewable energy development reaching proportions of 84.7%–119% of the total power demand by 2040

Editorial [to] Themed issue on sustainability in energy and buildings, part 1

This themed issue includes the selected papers from the proceedings of the seventh International Conference on Sustainability and Energy in Buildings 2015 (SEB15), which was successfully held in the vibrant city of Lisbon, Portugal and was organised by the Universidade Nova de Lisbon (New University of Lisbon) in partnership with KES International. Annually, the conference brings together researchers and government and industry professionals to discuss the future of energy in buildings, neighbourhoods and cities from a theoretical, practical, implementation and simulation perspective

Spatio-temporal associations of air pollutant concentrations, GP respiratory consultations and respiratory inhaler prescriptions: a 5-year study of primary care in the borough of Lambeth, South London.

BACKGROUND: Although the associations of outdoor air pollution exposure with mortality and hospital admissions are well established, few previous studies have reported on primary care clinical and prescribing data. We assessed the associations of short and long-term pollutant exposures with General Practitioner respiratory consultations and inhaler prescriptions. METHODS: Daily primary care data, for 2009-2013, were obtained from Lambeth DataNet (LDN), an anonymised dataset containing coded data from all patients (1.2 million) registered at general practices in Lambeth, an inner-city south London borough. Counts of respiratory consultations and inhaler prescriptions by day and Lower Super Output Area (LSOA) of residence were constructed. We developed models for predicting daily PM2.5, PM10, NO2 and O3 per LSOA. We used spatio-temporal mixed effects zero inflated negative binomial models to investigate the simultaneous short- and long-term effects of exposure to pollutants on the number of events. RESULTS: The mean concentrations of NO2, PM10, PM2.5 and O3 over the study period were 50.7, 21.2, 15.6, and 49.9 μg/m3 respectively, with all pollutants except NO2 having much larger temporal rather than spatial variability. Following short-term exposure increases to PM10, NO2 and PM2.5 the number of consultations and inhaler prescriptions were found to increase, especially for PM10 exposure in children which was associated with increases in daily respiratory consultations of 3.4% and inhaler prescriptions of 0.8%, per PM10 interquartile range (IQR) increase. Associations further increased after adjustment for weekly average exposures, rising to 6.1 and 1.2%, respectively, for weekly average PM10 exposure. In contrast, a short-term increase in O3 exposure was associated with decreased number of respiratory consultations. No association was found between long-term exposures to PM10, PM2.5 and NO2 and number of respiratory consultations. Long-term exposure to NO2 was associated with an increase (8%) in preventer inhaler prescriptions only. CONCLUSIONS: We found increases in the daily number of GP respiratory consultations and inhaler prescriptions following short-term increases in exposure to NO2, PM10 and PM2.5. These associations are more pronounced in children and persist for at least a week. The association with long term exposure to NO2 and preventer inhaler prescriptions indicates likely increased chronic respiratory morbidity