A description and assessment of a small renewable energy community located in Crete, Greece is presented. The community included private residential and agricultural activities without any involvement of the public se...A description and assessment of a small renewable energy community located in Crete, Greece is presented. The community included private residential and agricultural activities without any involvement of the public sector. Small-scale decentralized energy systems were used. Solar energy and solid biomass which are locally available covered most of the heat and electricity requirements in the community. Renewable energy technologies used include solar thermal energy, solar-PV and solid biomass burning utilizing olive tree wood and olive kernel wood. These technologies are mature, reliable, well proven in Crete and cost-effective. Existing energy systems were generating 857,877 kWh per year covering 94.46% of the current energy requirements in the community, significantly reducing its emissions at 278,494 kg CO2 per year. The addition of a new solar-PV system with nominal power of 33.6 kWp could cover all the remaining electricity needs in the community, transforming it to a zero-CO2 emission community due to energy use. The total installation cost of the existing renewable energy systems in the community was estimated at 0.16€ per total kWh of thermal and electric energy generated annually and at 0.50€ per ton of CO2 emissions saved annually. Results indicated that the creation of the above-mentioned small local energy community is economically viable, environmental friendly and socially accepted. Therefore it could be replicated in other territories with similar availability of renewable energies, increasing their energy autonomy and sustainability.展开更多
Olive pomace plants process olive paste, a waste product of olive mills which produces crude olive kernel oil and olive kernel wood. Olive kernel wood has very good burning characteristics, high heat content, low cost...Olive pomace plants process olive paste, a waste product of olive mills which produces crude olive kernel oil and olive kernel wood. Olive kernel wood has very good burning characteristics, high heat content, low cost and it is used as a renewable solid fuel replacing liquid fuel and heating oil. Part of the produced olive kernel wood is consumed inside the factory for heat generation and the rest is sold to heat consumers. It has been estimated that a typical olive pomace plant located in Crete, Greece consumes 42.86% of the produced olive kernel wood for its own heat generation, while the remaining 57.14% is sold to various heat consumers. 99.1% of the energy used in these plants is consumed for heating and the rest, 0.9%, for lighting and the operation of various electric devices. Olive pomace plants utilize a renewable solid fuel, which is carbon neutral, for the production of thermal energy. Therefore their CO<sub>2</sub> emissions regarding energy utilization are due to electricity use. Installation of solar-PV panels in the plant could generate annually all the electricity needed for its operation. The current legal framework in Greece through net-metering allows the offsetting of grid electricity consumed in factories with PV electricity. The required capital cost of a solar-PV system installed in a typical olive pomace plant located in Crete, Greece in order to offset the grid electricity consumed annually has been estimated at 185,832€, the payback period of 5.33 years and the net present value at 555,671€. Since the plant could utilize only solid biomass for heat generation and could offset the grid electricity consumption with solar electricity, its total CO<sub>2</sub> emissions due to energy use would be zero contributing positively to climate stabilization.展开更多
An increase in energy efficiency and a reduction of carbon emissions in buildings are prerequisites for mitigating climate change. Public buildings should be energy-refurbished for minimizing their energy use, complyi...An increase in energy efficiency and a reduction of carbon emissions in buildings are prerequisites for mitigating climate change. Public buildings should be energy-refurbished for minimizing their energy use, complying with EU legislation and directives. The creation of net zero carbon emissions prisons in Crete, Greece with reference to the agricultural prison of Agia has been examined. The prison’s capacity is 178 offenders and the annual energy consumption has been estimated at 4000 KWh/prisoner. The use of a solar thermal system for hot water production and a solar-PV system for electricity generation has been proposed for generating the energy required in the prison. Two scenarios have been examined. In the first, the two solar energy systems would generate all the required energy in the prison, while in the second, the two solar energy systems would generate 50% of the annual required energy in the prison, and the rest would be produced by fossil fuels. A tree plantation, either with olive trees or with Eucalyptus trees, would be created for offsetting the carbon emissions due to fossil fuels used in the prison. The surface of the flat plate solar collectors in the solar thermal system has been estimated at 113.9 M<sup>2</sup> to 227.8 M<sup>2</sup> while its cost is at 34,170€ to 68,340€. The nominal power of the solar-PV system has been estimated at 151.9 KW<sub>p</sub> to 303.8 KW<sub>p</sub> while its cost is at 182,280€ to 364,560€. The area of the tree plantation sequestrating 50% of the current CO<sub>2</sub> emissions due to fossil fuels use in the prison has been estimated at 14.74 ha for olive trees and at 5.9 ha for Eucalyptus trees. The results indicated that the energy refurbishment in Agia’s agricultural prison in Crete, Greece, in order to zero its annual net carbon emissions, is feasible.展开更多
文摘A description and assessment of a small renewable energy community located in Crete, Greece is presented. The community included private residential and agricultural activities without any involvement of the public sector. Small-scale decentralized energy systems were used. Solar energy and solid biomass which are locally available covered most of the heat and electricity requirements in the community. Renewable energy technologies used include solar thermal energy, solar-PV and solid biomass burning utilizing olive tree wood and olive kernel wood. These technologies are mature, reliable, well proven in Crete and cost-effective. Existing energy systems were generating 857,877 kWh per year covering 94.46% of the current energy requirements in the community, significantly reducing its emissions at 278,494 kg CO2 per year. The addition of a new solar-PV system with nominal power of 33.6 kWp could cover all the remaining electricity needs in the community, transforming it to a zero-CO2 emission community due to energy use. The total installation cost of the existing renewable energy systems in the community was estimated at 0.16€ per total kWh of thermal and electric energy generated annually and at 0.50€ per ton of CO2 emissions saved annually. Results indicated that the creation of the above-mentioned small local energy community is economically viable, environmental friendly and socially accepted. Therefore it could be replicated in other territories with similar availability of renewable energies, increasing their energy autonomy and sustainability.
文摘Olive pomace plants process olive paste, a waste product of olive mills which produces crude olive kernel oil and olive kernel wood. Olive kernel wood has very good burning characteristics, high heat content, low cost and it is used as a renewable solid fuel replacing liquid fuel and heating oil. Part of the produced olive kernel wood is consumed inside the factory for heat generation and the rest is sold to heat consumers. It has been estimated that a typical olive pomace plant located in Crete, Greece consumes 42.86% of the produced olive kernel wood for its own heat generation, while the remaining 57.14% is sold to various heat consumers. 99.1% of the energy used in these plants is consumed for heating and the rest, 0.9%, for lighting and the operation of various electric devices. Olive pomace plants utilize a renewable solid fuel, which is carbon neutral, for the production of thermal energy. Therefore their CO<sub>2</sub> emissions regarding energy utilization are due to electricity use. Installation of solar-PV panels in the plant could generate annually all the electricity needed for its operation. The current legal framework in Greece through net-metering allows the offsetting of grid electricity consumed in factories with PV electricity. The required capital cost of a solar-PV system installed in a typical olive pomace plant located in Crete, Greece in order to offset the grid electricity consumed annually has been estimated at 185,832€, the payback period of 5.33 years and the net present value at 555,671€. Since the plant could utilize only solid biomass for heat generation and could offset the grid electricity consumption with solar electricity, its total CO<sub>2</sub> emissions due to energy use would be zero contributing positively to climate stabilization.
文摘An increase in energy efficiency and a reduction of carbon emissions in buildings are prerequisites for mitigating climate change. Public buildings should be energy-refurbished for minimizing their energy use, complying with EU legislation and directives. The creation of net zero carbon emissions prisons in Crete, Greece with reference to the agricultural prison of Agia has been examined. The prison’s capacity is 178 offenders and the annual energy consumption has been estimated at 4000 KWh/prisoner. The use of a solar thermal system for hot water production and a solar-PV system for electricity generation has been proposed for generating the energy required in the prison. Two scenarios have been examined. In the first, the two solar energy systems would generate all the required energy in the prison, while in the second, the two solar energy systems would generate 50% of the annual required energy in the prison, and the rest would be produced by fossil fuels. A tree plantation, either with olive trees or with Eucalyptus trees, would be created for offsetting the carbon emissions due to fossil fuels used in the prison. The surface of the flat plate solar collectors in the solar thermal system has been estimated at 113.9 M<sup>2</sup> to 227.8 M<sup>2</sup> while its cost is at 34,170€ to 68,340€. The nominal power of the solar-PV system has been estimated at 151.9 KW<sub>p</sub> to 303.8 KW<sub>p</sub> while its cost is at 182,280€ to 364,560€. The area of the tree plantation sequestrating 50% of the current CO<sub>2</sub> emissions due to fossil fuels use in the prison has been estimated at 14.74 ha for olive trees and at 5.9 ha for Eucalyptus trees. The results indicated that the energy refurbishment in Agia’s agricultural prison in Crete, Greece, in order to zero its annual net carbon emissions, is feasible.
