Techno-economic Analysis of an Off-Grid Photovoltaic Natural Gas Power System for a University[edit | edit source]
P. Sunderan1* , B. Singh2 , N.M.Mohamed2, N.S. Husain1
This paper mainly focuses on determining the technical and economical feasibility of a PV-natural gas hybrid power system to supply electricity and energy. The inclusion of PV reduced the amount of natural gas burned in the hybrid system. HOMER software was used to size, simulate and evaluate the hybrid power system in this analysis. The simulations provide some insights into the monthly electricity generated by the photovoltaic-natural gas system, net present cost (NPC) and cost of energy (COE) of the system, renewable fraction (RF) and greenhouse gas emissions of the system.
NOTES[edit | edit source]
- This analysis is conducted with the goal of reducing the natural gas consumption of the existing non-renewable energy source. By the reduction of natural gas usage,it helped in the reduction of GHG emission.
- The solar irridiance data for complete year has been observed. During novemeber to january the radiation are very low as observed from the graph.
Electrical load[edit | edit source]
- In this monthly and hourly load profile i.e electrical demand has been noted. From hours 8.00 to 18.00 load demand is high.
HOMER software[edit | edit source]
- The simulation is performed using HOMER software. It is used to design and perform economic feasibility analysis of the hybrid power system.
- The schematic disgram is as follows:
- The gas generator is connected to the AC bus which supplies the load.
- The output of PV system is connected to the DC bus.
- This DC output is connected to AC bus through DC to AC converter.
- The analysis was done for 25 years duration for annual rate of 4%.
- Once the data are available, the simulation can be run where calculations are performed to determine if the available renewable resources is able to meet the load demand. When the renewable resource is not sufficient to meet the load demand, the generator system or grid connection is considered.
Results and Discussion[edit | edit source]
- Out of the total power generated 9% was generated by the PV arrays. The detailed monthly graph for power generated by each unit was also provide, which shows that the PV generation was more effective during the month of August and March. Even the total operating cost of the system can be estimated.
- The natural gas consumption by the generator when it is working with PV arrays is less as compared to it standalone operation.
- Emission also reduces by a considerable amount.
A HYBRID ARCHITECTURE FORPHOTOVOLTAIC SYSTEM (PV) INCORPORATING COMBINED HEAT AND POWER (CHP) UNITS[edit | edit source]
HAJIAN GELAREH AND AHADI MOHAMMAD SAEED
This paper focuses on meeting the electricity demand of a building and use the heat byproduct of this process for internal usage, simultaneously.The integration of the elements connected to the power system to offer great benefits such as better efficiency, reliability, with possible integration of renewable energy sources. In this PV is connected to the CHP in order to fulfill the demand. The main purpose of this paper is to reduce the GHG emission and fossil fuel consumption.
NOTES[edit | edit source]
PV system with grid[edit | edit source]
- In this the PV is mounted. The output of the PV is DC which is given to the inverter which converts DC to AC. The AC is supplied to the load in order to fulfill the electric demand. Moreover, the excess electricity produced by the PV after fulfilling the demand for the load is fed into the grid.
CHP unit[edit | edit source]
- The CHP unit consists of
1) Fuel storage.
2) Heat Exchanger.
3) Inveter.
4) Engine.
5) Heat reservior.
The fuel storage is used to store fuel to operate the engine. The engine converts the mechanical energy into electrical energy. The output of the engine is DC which is converted to AC using inverter. The waste heat produced is given to the heat exchanger which is used for space heating and hot water.
Hybrid CHP+Pv system[edit | edit source]
- The PV+CHP system is used in order to increase the overall efficiency. If Pv is not able to fulfill the load demand. Then CHP unit operates and fulfills the load demand. The thermal demand is fulfilled by the CHP unit. The extra energy is fed into the grid.
Operational strategy and marginal costs in simple trigeneration systems[edit | edit source]
M.A. Lozano, M. Carvalho, L.M. Serra
This paper focuses on the operation of a trigeneration system. Trigeneration systems (CHCP: Combined Heating, Cooling and Power generation) allow greater operational flexibility at sites with a variable demand for energy in the form of heating and cooling. This paper also focuses on thermoeconomic analysis based on production cost, to obtain cost of energy flow and final product.
NOTES[edit | edit source]
Efficieny of consumedd fuel is one of the main benefits of trigeneration system which is used for the production of three type of energies heat, cooling and electricity. The advantages of trigeneration are primary energy saving, reduction in GHG emission and lower cost of energy services.
Simple trigeneration system[edit | edit source]
- It consists of a cogeneration unit and an absorption chiller. The cogeneration unit consists of prime mover like gas turbine, reciprocating engine etc. which converts the fuel energy into mechanical energy. The alternator convert this mechanical energy into electrical energy. It also consists of heat recovery unit.
- The absorption chiller can produce cooling using the recovered heat. The purpose of trigeneration unit is to fulfill the different energy demands like electricity, heat and cooling.
- A optimal model state was obtained by solving the linear modelling program. The objective was to minimize the operating cost.
Thermoeconomic analysis[edit | edit source]
- The objective of thermoeconomics is to explain the cost formation process throughout the system from the energy resources to the final products.
- Dual prices and marginal costs information are important for two reasons:
(i) to identify which operation constraint could be changed to improve the solution.
(ii) to react automatically when external operational circumstances (prices of resources and product demands) change.
- The cogeneration module operates at full load and electricity is purchased; therefore, if an additional unit of electricity is required, it can only be obtained by purchasing it from the electric grid. If an additional electricity is required, it must be obtained through the purchased electricity, because the cogeneration module is operating at full load. An additional unit of heat will be produced by the auxiliary boiler.
- The waste heat from the cogeneration unit is used to fulfill heating and cooling demand.
Conclusion[edit | edit source]
- The linear programming model developed allows the determination of the optimal operation mode corresponding to the minimum variable cost.
- The use of trigeneration helped to reduce the cost of primary energy source, reduce GHG emission.
Analysis of hybrid energy systems for application in southern Ghana[edit | edit source]
Muyiwa S. Adaramolaa, Martin Agelin-Chaabb, Samuel S. Paulc
This paper focus on an economic analysis of the feasibility of utilizing a hybrid energy system consisting of solar, wind and diesel generators for application in remote areas. HOMER software was used for actual load data and wind data in order to carry out simulation. The paper also presented Sensitivity analysis on the effect of changes in wind speed, solar global radiation and diesel price on the optimal energy was investigated and the impact of solar PV price on the LCOE for a selected hybrid energy.
NOTES[edit | edit source]
- A stand-alone solar energy system cannot provide electricity around the clock throughout the year if there are cloudy days when there is no sunlight due to its intermittent nature.
- Similarly a stand-alone wind energy system may not produce usable energy for considerable portion of time during the year due to relatively high cut-in wind speed.
- Hence, hybrid system which included both of this technologies will be a good option for satisfying energy needs.
LOAD AND ENERGY RESOURCES[edit | edit source]
- The data for cost of fuel for the generator and electrical load as well as the solar and wind energy resources were obtained.
POWER PLANT COMPONENTS[edit | edit source]
- The PV–wind–Gen hybrid consists of two parts:
1) Power plant: which consists of PV module, wind turbine, diesel generator, battery and power converter.
2) Mini grid transmission and distribution system.
- The hybrid energy system is designed and analyzed using HOMER software.The HOMER software requires information about the cost (capital, replacement, operation and maintenance), number (or size) of units to be used, operating hours and lifetime, and other specific component properties for every component in energy system.
Components in energy system: Output power[edit | edit source]
- The ouput power of PV module can be calculated from the equation given in the paper and the PV specificaions.
- The output power of Wind resource can be calculated by HOMER software.
- The fuel consumption of the diesel generator can be calculated.
- The battery is used to provide the energy when hybrid sytem is not able to fulfill the electrical need of the load.
- A power converter maintains the flow of energy between the AC electrical load and DC components of the hybrid energy system.
ECONOMICS PARAMETERS and CALCULATIONS[edit | edit source]
- Cost of fixed and the initial capital cost has been calculated and maintenance cost for the hybrid system per year is also been considered.
RESULTS[edit | edit source]
- It can be seen from the simulation that wind and PV hybrid can fulfill around 50% of the power demand.
- Using the renewable hybrid can reduce the GHG emission, cost of fuel, saves energy and reduce the maintenance cost.
Economic and environmental based operation strategies of a hybrid photovoltaic–microgas turbine trigeneration system[edit | edit source]
Firdaus Basrawia, Takanobu Yamadab, Shinya Obara
This paper focuses on environmental and economic performance of photovoltaic and CHP system with various operation strategies. Economic performance was analyzed using life cycle cost analysis and environmental performance was analyzed based on the actual emissions of GHG.
NOTES[edit | edit source]
- Power plant can be designed as cogeneration system or trigeneration system in order to increase the performance of the system.
- The PV system will be used to fulfill the demand of the load during the day time and during remaining period the cogeneration unit fulfills it. The exhaust heat can be stored and used later.
- Battery is used to store the excess power and supplied during off period.
Model of the hybrid energy system[edit | edit source]
- The PV and MGT generate electricity but output of PV is DC which needs to be converted to AC using inverter. Excess energy can be stored in the battery. The current must be converted to DC during the charging process, and converted back to AC during the discharging process.
- Waste heat of the MGT is recovered by the heat exchanger, and it is used to cover water heating demand of the houses, and the rest is supplied to the absorption chiller. The absorption chiller converts heat energy in cooling energy.
- Power demand will be covered by the combination of PV and MGT. Imbalance between power supply and demand can be controlled by the battery.
Economic analysis of the hybrid system[edit | edit source]
- Life cycle cost is evaluated by the hybrid energy performance of the system. The maintanence cost and othe factors were taken into consideration for economic analysis fo the hybrid system.
- The two strategies were taken into consideration: The operating strategy and the combined cycle gas turbine.
Conclusion[edit | edit source]
Hybrid energy system with power-match operation strategy had the highest net Profit compared to other hybrid systems but had more CO2 emission compared to combined cycle gas turbine. Combined cycle gas turbine is best in economic and emission performance compared to operational strategy.
Energetic hybrid systems for residential use[edit | edit source]
Mustapha Hatti, Nachida Kasbadji Merzouk and Achour Mahrane
This paper presents combined technologies (wind, fuel cells and solar power) to achieve synergies in terms of cost and energetic efficiency compared to systems based on a single energy source and energy conversion technology. This paper also focuses on models required to simulate the components and sub-systems of a Wind-Photovoltaic's-Fuel cells-Micro-turbine and Diesel power system.
NOTES[edit | edit source]
The use of hybrid renewable energy resource can provide higher quality and more reliable Power and it reduces the CO2 emission and reduce the dependence of supply on fossil fuel. As wind and solar are intermittent they are not consistent so they require additional source of power.
ENERGY CONSERVATION TECHNOLOGIES[edit | edit source]
1) Photovoltaic: A PV power supply system is established as a reliable and economical source of electricity in residential areas.
2) Batteries and superconductors: They are used to convert chemical energy into electrical energy. They are used to store excess of energy which can be used for future purpose during shortage.
3) Diesel Generators: Diesel engine is coupled directly to the synchronous generator.
4) Wind generator:
5) CHP (FUEL CELL+MICRO-TURBINE): The power converter is very clean and efficient. Efficiency upto 82% can be obtained. The components of a microturbine are: compressor, turbine, combustion chamber, boiler and generator: permanent magnet synchronous machine.
ADVANTAGES[edit | edit source]
- Reduction of CO2 emission.
- Reduction cost primary fuels.
- Increase in the overall efficiency of the system.
- Battery is used to provide power when renewable source does not fulfill the power demand.
- Increases the economy of Wind and solar power and help increasing their penetration level.
Large-scale integration of wind power into different energy systems[edit | edit source]
Henrik Lund
The paper focuses on the ability of different energy systems and regulation strategies to integrate wind power. The wind power is used to reduce CO2 emission. Energy systems and regulation strategies are analysed in the range of a wind power input from 0 to 100% of the electricity demand. 50% of the electricity demand is produced in CHP, a number of future energy systems with CO2 reduction potentials are analysed, i.e. systems with more CHP, systems using electricity for transportation (battery or hydrogen vehicles) and systems with fuel-cell technologies.
NOTES[edit | edit source]
ENERGY PLAN MODEL[edit | edit source]
The Energy PLAN model is an input/output model. The energy system in the Energy PLAN model includes heat production from solar thermal. With the CHP system electricity is also produced using renewable energy resources.
The energy plan model consists of the following units
1)PV UNIT
2)CHP UNIT
3)WIND INPUT
4)TRADITIONAL POWER PLANT
Technical analysis[edit | edit source]
The technical analyses distinguish between the two following strategies:
Strategy I:Meeting heat demand
Strategy II:Meeting both heat and electricity demands.
1) Annual consumption of electricity, even required for transport.
2) Solar thermal and industrial CHP production input for district heating.
3) Capacity and operating efficiency of CHP, Heat pumps, Boilers, power stations.
Conclusion[edit | edit source]
- Reduce GHG emission.
- CHP improves the operation efficiency.
Environmental impacts of microgeneration: Integrating solar PV, Stirling engine CHP and battery storage[edit | edit source]
Paul Balcombea, Dan Rigbyb, Adisa Azapagic
This paper focuses on a microgeneration system combining solar PV, combined heat and power plant (CHP) and battery storage could potentially mitigate these problems improving energy self-sufficiency. The main goal of the paper is to determine the environmental impacts associated with an integrated solar PV, SECHP and battery storage system installed in a household and compare it to the impacts from a conventional supply of electricity from the grid and heat from a domestic boiler.
NOTES[edit | edit source]
- Due to the intermittent nature of PV, it lead to the problem of grid balancing. The solution for this is coupling solar PV with the battery which could reduce uncontrolled exports.
- Coupling solar PV and battery storage with a Stirling engine combined heat and power plant (SECHP) would help further improving self sufficiency
of supply.
Installation and operation of the PV–SECHP-battery system[edit | edit source]
- The SECHP unit supplies heat demand and electricity demand is fulfilled by PV and CHP both.
- When electricity demand from the PV and CHP exceeds, it is stored in the battery. When the battery gets fully charged the power is transferred into the grid.
- When electricity generated by PV and CHP is lower than the demand it is then supplied by the battery. Even the battery is unable to fulfill the demand it is then supplied by the grid.
- The average efficiency of SECHP operation is found to be 94.7%, including start-ups and shut-downs.
Environmental impacts of the PV–SECHP-battery system[edit | edit source]
- The environmental impacts of the PV-SECHP-battery system are very low compared to the conventional energy system.
Conclusion[edit | edit source]
Using of SECHP has reduced the CO2 emission compared to conventional energy system. Moreover, the global warming is reduced by 17% if the system is operated more efficiently.
Renewable energy strategies for sustainable development[edit | edit source]
Henrik Lund
This paper focuses on the renewable energy (wind, solar, wave and biomass) in the making of strategies for a sustainable development. Such strategies contains three major technological changes: energy savings, efficiency improvements in the energy production, and replacement of fossil fuels by various sources of renewable energy.
NOTES[edit | edit source]
- The share of electricity supply by CHP is around 50% and wind supplies around 20% of the electricity demand.
- The Energy PLAN model has been used for a number of similar analyses of large-scale integration of renewable energy, efficiency improvements in the energy production, and replacement of fossil fuels by various sources of renewable energy.
- Three technologies have been considered for the analysis: Savings, Efficiency and RES(Renewable Energy Sources).
Economic Analysis of Microgrids[edit | edit source]
Asanol, H. ; Tokyo Univ., Tokyo ; Bandol, S
This paper focuses on technical feasibility of microgrids with renewable energy. This paper also focuses on methodology for economic design and optimal operation of microgrids with renewable energy sources.
NOTES[edit | edit source]
- The microgrid involves interconnection of small distributed generation (DG)DGs and loads through a local grid.
ECONOMICS OF THE MICROGRIDS[edit | edit source]
- Cost of microgrid include capital costs of equipment, fuel cost of DGs, purchased cost and selling price of electricity from the main grid, construction costs of distribution lines.
- Due to the intermittent nature of wind power and PV, the microgrids are used to manage intermittency with controllable DGs such as gas engine and battery storage.
DESIGN OF OPTIMAL CAPACITY OF EQUIPMENT[edit | edit source]
- CHP is used to increase the renewable energy near the demand side because CHP is used to adjust the output of the intermittent renewable sources.
- The efficiency due to PV increases by 40%.
System Configuration[edit | edit source]
- The system is composed of gas-engine(GE), battery(BAT), heat exchangers(HE), thermal storage tanks(TS), a steam absorption refrigerator(RS), a gas-absorption chiller(RG), and a gas-boiler(GB).
- The surplus electricity is fed into the grid during the off peak time to improve the power generation efficiency.
Conclusion[edit | edit source]
- Microgrids can improve the services of loads with cleaner, more efficient, more reliable technologies.
