Research Output
1 - 10 of 18
Publication
Feasibility study of an offshore wind farm in the Aegean Sea, Turkey
2018-01, Satir, Mert, Murphy, Fionnuala, McDonnell, Kevin
Offshore wind power technology holds the potential for tackling major problems associated with energy and climate change as well as triggering economic growth and providing employment opportunities. Offshore wind power has the potential to play a key role for Turkey in achieving stated 2023 energy targets due to the country's favourable geographic location and coastline. However, there are currently no offshore wind farm projects in Turkey. The aim of this study is to determine the feasibility of an offshore wind farm in the Turkish seas. Prior to that, offshore wind market in the EU is reviewed, and the current status regarding the wind power market and supporting mechanisms are reviewed regarding the situation in Turkey. A location is proposed in the Aegean Sea, based on consideration of wind speeds and other factors. Technical analysis is conducted with the use of windPro software, and potential annual energy production of the proposed project is calculated. Combined with the economic analysis, feasibility of such an offshore wind farm is discussed. Issues with the current supporting mechanism are identified, and solutions are proposed for the future development of offshore wind farms in Turkey.
Publication
Potential to Increase Indigenous Biodiesel Production to help meet 2020 Targets - An EU perspective with a focus on Ireland
2014-07, Murphy, Fionnuala, Devlin, Ger, Deverell, Rory, McDonnell, Kevin
The biofuels penetration rate target in Ireland for 2013 is 6% by volume. In 2012 the fuel blend reached 3%, with approximately 70 million litres of biodiesel and 56 million litres of ethanol blended with diesel and gasoline respectively. For January and February 2013, the blend rate had only reached 2.7%. The target of 10% by 2020 remains which equates to approximately 420 million litres. Achieving the biofuels target would require 345 ktoe by 2020 (14,400 TJ). Utilising the indigenous biofuels outlined in this paper leaves a shortfall of approximately 12,000 TJ or 350 million litres (achieving 17% of the 10% target) that must be either be imported or met by other renewables. 70% of indigenous production from one
biodiesel plant is currently from TME and UCOME. If this remains for 2020 then only 30% remains equating to approximately 10 million litres indigenous production for a second biodiesel plant (30% of 21+13 million litres) which has planned capacity of 40 million litres (36,000 t). In terms of the EU biofuels sustainability criteria, up to 2017, a 35% GHG emissions reduction is required compared to fossil fuels. From 2017 onwards, a 50% GHG reduction is required for existing installations and a 60% reduction for new installations.
Publication
Life cycle assessment of biomass-to-energy systems in Ireland modelled with biomass supply chain optimisation based on greenhouse gas emission reduction
2016-08-15, Murphy, Fionnuala, Sosa, Amanda, McDonnell, Kevin, Devlin, Ger
The energy sector is the major contributor to GHG (greenhouse gas emissions) in Ireland. Under EU Renewable energy targets, Ireland must achieve contributions of 40%, 12% and 10% from renewables to electricity, heat and transport respectively by 2020, in addition to a 20% reduction in GHG emissions. Life cycle assessment methodology was used to carry out a comprehensive, holistic evaluation of biomass-to-energy systems in 2020 based on indigenous biomass supply chains optimised to reduce production and transportation GHG emissions. Impact categories assessed include; global warming, acidification, eutrophication potentials, and energy demand. Two biomass energy conversion technologies are considered; co-firing with peat, and biomass CHP (combined heat and power) systems. Biomass is allocated to each plant according to a supply optimisation model which ensures minimal GHG emissions. The study shows that while CHP systems produce lower environmental impacts than co-firing systems in isolation, determining overall environmental impacts requires analysis of the reference energy systems which are displaced. In addition, if the aims of these systems are to increase renewable energy penetration in line with the renewable electricity and renewable heat targets, the optimal scenario may not be the one which achieves the greatest environmental impact reductions.
Publication
Biofuel Production in Ireland—An Approach to 2020 Targets with a Focus on Algal Biomass
2013-12-04, Murphy, Fionnuala, Devlin, Ger, Deverell, Rory, McDonnell, Kevin
Under the Biofuels Obligation Scheme in Ireland, the biofuels penetration rate target for 2013 was set at 6% by volume from a previous 4% from 2010. In 2012 the fuel blend reached 3%, with approximately 70 million L of biodiesel and 56 million L of ethanol blended with diesel and gasoline, respectively. Up to and including April 2013, the current blend rate in Ireland for biodiesel was 2.3% and for bioethanol was 3.7% which equates to approximately 37.5 million L of biofuel for the first four months of 2013. The target of 10% by 2020 remains, which equates to approximately 420 million L yr−1. Achieving the biofuels target would require 345 ktoe by 2020 (14,400 TJ). Utilizing the indigenous biofuels in Ireland such as tallow, used cooking oil and oil seed rape leaves a shortfall of approximately 12,000 TJ or 350 million L (achieving only 17% of the 10% target) that must be either be imported or met by other renewables. Other solutions seem to suggest that microalgae (for biodiesel) and macroalgae (for bioethanol) could meet this shortfall for indigenous Irish production. This paper aims to review the characteristics of algae for biofuel production based on oil yields, cultivation, harvesting, processing and finally in terms of the European Union (EU) biofuels sustainability criteria, where, up to 2017, a 35% greenhouse gas (GHG) emissions reduction is required compared to fossil fuels. From 2017 onwards, a 50% GHG reduction is required for existing installations and from 2018, a 60% reduction for new installations is required.
Publication
Miscanthus production and processing in Ireland: An analysis of energy requirements and environmental impacts
2013-07, Murphy, Fionnuala, Devlin, Ger, McDonnell, Kevin
The environmental impact of bioenergy supply systems can be determined using life cycle assessment methodologies. This study focuses on the impact of production of Miscanthus pellets and briquettes, potentially used to satisfy renewable energy requirements in Ireland. The impact categories considered are particularly important when assessing bioenergy systems; global warming potential, acidification potential, eutrophication potential, and energy demand. The scope of the study incorporates Miscanthus cultivation, harvest, processing and transport to a biomass distributor. The aim of the research is to evaluate the effects of changes in keys variables on the overall environmental impacts of the system. The scenarios examined include replacement of synthetic fertilisers with biosolids, Miscanthus processing by pelleting and briquetting, and transport distances of 50 and 100 km. Results indicate that maintenance and processing of the Miscanthus crop have the most environmental impacts with transport having less of an effect. Replacing synthetic fertiliser with biosolids results in a reduction in global warming potential of 23–33% and energy demand of 12–18%, but raises both acidification and eutrophication potential by 290–400% and 258–300%, respectively. Pelleting of Miscanthus requires more energy than briquetting, hence has higher impacts in each category assessed. Increasing the transport distance from 50 to 100 km, results in a small increase in each impact category. Miscanthus briquette production compares favourably with wood pellet, kerosene, and coal production, with Miscanthus pelleting proving more environmentally damaging.
Publication
Forest Biomass Supply Chains in Ireland: A Life Cycle Assessment of GHG Emissions and Primary Energy Balances
2014-03-01, Murphy, Fionnuala, Devlin, Ger, McDonnell, Kevin
The demand
for wood for energy production in Ireland is predicted to double from 1.5
million m3 over bark (OB) in 2011 to 3 million m3 OB by
2020. There is a large potential for additional biomass recovery for energetic
purposes from both thinning forest stands and by harvesting of tops and
branches, and stumps. This study builds on research within the wood-for-energy
concept in Ireland by analysing the energy requirements and greenhouse gas
emissions associated with thinning, residue bundling and stump removal for
energy purposes. To date there have been no studies on harvesting of residues
and stumps in terms of energy balances and greenhouse gas emissions across the
life cycle in Ireland. The results of the analysis on wood energy supply chains
highlights transport as the most energy and greenhouse gas emissions intensive
step in the life cycle. This finding illustrates importance of localised
production and use of forest biomass. Production of wood chip, and shredded
bundles and stumps, compares favourably with both other sources of biomass in
Ireland and fossil fuels.
Publication
Greenhouse gas and energy based life cycle analysis of products from the Irish wood processing industry
2015-01-09, Murphy, Fionnuala, Devlin, Ger, McDonnell, Kevin
The timber industry in Ireland is an important producer of wood products for export and indigenous use, and supplies significant volumes of sawmill co-products as biomass for energy generation. This research expands existing knowledge on the environmental impacts of wood supply chains in Ireland by widening the analysis to incorporate the wood processing stage. The study determines and analyses energy and material inputs in the production of several timber products; sawnwood, wood chip, wood-based panel (WBP) boards and wood pellets, with an analysis of the resulting greenhouse gas emissions. Forestry operations and transportation make an important contribution to overall emissions. Electricity usage is responsible for the majority of emissions in sawmilling. Integration of combined heat and power (CHP) systems with sawmilling and pellet manufacture reduces greenhouse gas (GHG) emissions. The penetration of renewables in the Irish national grid mix is forecast to increase by 2020 in line with EU renewable energy targets. Analysis shows that the forecast fall in the carbon intensity of the grid will have a positive effect on the reduction of GHG emissions from the wood processing supply chains. Wood energy products compare favourably with other sources of biomass energy and with fossil fuels.
Publication
Miscanthus production and processing in Ireland: An analysis of energy requirements and environmental impacts
2013-07, Murphy, Fionnuala, Devlin, Ger, McDonnell, Kevin
The environmental impact of bioenergy supply systems can be determined using life cycle assessment methodologies. This study focuses on the impact of production of Miscanthus pellets and briquettes, potentially used to satisfy renewable energy requirements in Ireland. The impact categories considered are particularly important when assessing bioenergy systems; global warming potential, acidification potential, eutrophication potential, and energy demand. The scope of the study incorporates Miscanthus cultivation, harvest, processing and transport to a biomass distributor. The aim of the research is to evaluate the effects of changes in keys variables on the overall environmental impacts of the system. The scenarios examined include replacement of synthetic fertilisers with biosolids, Miscanthus processing by pelleting and briquetting, and transport distances of 50 and 100 km. Results indicate that maintenance and processing of the Miscanthus crop have the most environmental impacts with transport having less of an effect. Replacing synthetic fertiliser with biosolids results in a reduction in global warming potential of 23–33% and energy demand of 12–18%, but raises both acidification and eutrophication potential by 290–400% and 258–300%, respectively. Pelleting of Miscanthus requires more energy than briquetting, hence has higher impacts in each category assessed. Increasing the transport distance from 50 to 100 km, results in a small increase in each impact category. Miscanthus briquette production compares favourably with wood pellet, kerosene, and coal production, with Miscanthus pelleting proving more environmentally damaging.
Publication
Feasibility Study of Carbon Dioxide Plume Geothermal Systems in Germany−Utilising Carbon Dioxide for Energy
2020-05-12, McDonnell, Kevin, Molnár, Levente, Harty, Mary, Murphy, Fionnuala
To manage greenhouse gas emissions, directives on renewable energy usage have been developed by the European Commission with the objective to reduce overall emissions by 40% by 2030 which presents a significant potential for renewable energy sources. At the same time, it is a challenge for these energy technologies which can only be solved by integrated solutions. Carbon capture and storage combined with geothermal energy could serve as a novel approach to reduce CO2 emissions and at the same time facilitate some of the negative impacts associated with fossil fuel-based power plants. This study focuses on the technical and economic feasibility of combining these technologies based on a published model, data and market research. In the European Union, Germany is the most energy intensive country, and it also has an untapped potential for geothermal energy in the northern as well as the western regions. The CO2 plume geothermal system using supercritical carbon dioxide as the working fluid can be utilized in natural high porosity (10–20%) and permeability (2.5 × 10−14–8.4 × 10−16 m2) reservoirs with temperatures as low as 65.8 ◦C. The feasibility of the project was assessed based on market conditions and policy support in Germany as well as the geologic background of sandstone reservoirs near industrialized areas (Dortmund, Frankfurt) and the possibility of carbon capture integration and CO2 injection. The levelized cost of electricity for a base case results in € 0.060/kWh. Optimal system type was assessed in a system optimization model. The project has a potential to supply 6600/12000 households with clean energy (electricity/heat) and sequester carbon dioxide at the same time. A trading scheme for carbon dioxide further expands potential opportunities.
Publication
A Feasibility Assessment of Photovoltaic Power Systems in Ireland; a Case Study for the Dublin Region
2017-02-18, Murphy, Fionnuala, McDonnell, Kevin
Photovoltaic (PV) power generation is one of the cleanest sources for producing renewable energy; however uptake on the Irish renewable energy market to date has been low. There is a lack of support for solar PV systems in Ireland; there is currently no solar PV energy feed-in-tariff as there are for other renewable energy systems in Ireland. Despite the current lack of support, the Government has indicated that support for the uptake of solar PV installations will be provided through the provision of a feed-in tariff in the future. The aim of this study was to determine the feasibility of installing PV systems under Irish climatic conditions at a location based in Dublin, Ireland, from a technical, environmental and economic point of view. This was achieved by carrying out a life cycle assessment of potential environmental impacts, and analysis of energy and economic payback times relating to the proposed PV system. Four possible renewable feed-in-tariffs (based on existing feed-in-tariffs for other renewable energy systems) were considered to determine the effect of such tariffs on the overall economics of the proposed PV system. Results show that life cycle GHG emissions are 69 g CO2-eq per kWh generated by the system, significantly lower than the current electricity grid mix emissions of 469 g CO2-eq per kWh. It will take 5.23 years of operation of the solar plant to generate the same amount of energy (in terms of primary energy equivalent) that was used to produce the system itself. The economic payback time varies from 19.3 and 34.4 years depending on the rate of renewable energy feed-in-tariff applied. The costs for the production of PV electricity in this study are higher than is usual in countries where the solar PV market is more developed, e.g., Germany, due to constraints with building integration and lack of experienced PV installers. As more PV is deployed, the Irish PV installer base will increase and ‘learning by doing’ effects will allow installers to install projects more efficiently and quickly under Irish conditions, leading to significantly reduced costs.