RENEWABLE ENERGY SYSTEMS HYBRID ENERGY SYSTEMS APPLICATIONS

Transcription

1 1 RENEWABLE ENERGY SYSTEMS HYBRID ENERGY SYSTEMS APPLICATIONS Prof. Ibrahim El-mohr Prof. Ahmed Anas Lec

2 Water Heating Energy System Design 2 Compare the total cost ( Capital and running) for the following types of water heating: Solar type Electric type Gas type Assuming the following data: Daily hot water usage = 150 liters, 6 hours/day Hot water temperature = 65 C o Cold water temperature = 20 C o The capital cost of solar heater = L.E. 4000, Bank interest rate = 10%

3 Water Heating Energy System Design 3 Annual maintenance for solar system= L.E. 75 and 20 years life time. Assuming 30 days/year without solar thermal, and using electric system The capital cost of electric heater = L.E Annual maintenance for electric system= L.E. 50 The Electricity cost (flat rate) = 0.25 to 0.50 L.E. /kwh The capital cost of gas heater = L.E The cost of gas bottle, 14 m 3 = L.E. 20 to 30 L.E., and consumed in two weeks Annual maintenance for gas system= L.E. 60

4 Outline 4 Hybrid Energy Systems (HES) Application in Remote Area. HES Application in Rural Areas (WWTP)

5 Hybrid Energy Systems (HES) Application in 5 The problem:- Remote Area Optimum Sizing of Hybrid Energy System for Electrification of Remote Area in Egypt. Solution: Optimum topology selection ( Generator, PV, Wind, Hybrid, etc..), Percentage share of each source, Best operation strategies Optimum components sizing, Target : for minimum overall system cost.

6 Hybrid Energy System (HES) A hybrid energy system can be defined as: a combination of different, but complementary energy supply systems at the same place. It is commonly installed in remote areas isolated from the utility grid. 6

7 7 Advantages of Hybrid Energy System Reductions in size of diesel engine and battery storage system, which can save the fuel and reduce pollution. Improves the load factors and help saving on maintenance and replacement costs. The cost of electricity can be reduced by integrating diesel systems with renewable power generation.

8 8 Advantages of Hybrid Energy System (Cont.) Renewable hybrid energy systems can reduce the cost of high-availability renewable energy systems. This results from the system s ability to take advantage of the complementary diurnal (night/day) and seasonal characteristics of available renewable resources at a given site. On the other hand, high initial capital of the hybrid is a barrier to adopt the system thus the needs for long lasting, reliable and cost-effective system.

9 Hybrid Energy System/ Applications (Remote Area) 10 Villages Residential Buildings Hospitals Schools Farmhouses Hotels Irrigation systems Desalination Systems

10 Hybrid Energy System Optimization 11 General formulation of HES optimization problem: The problem is to develop a multi-objective model to design a HES with battery storage and diesel generators taking into consideration future system expansion. The design objectives are cost and CO2 gas emission minimization. The problem constraints are: (1) reliability constraint which dictates that a certain percentage of the peak demand must be secured as a reserve, (2) energy balance constraint.

11 HES Optimization Modeling Tools 12 HOMER: Hybrid Optimization Model for Electric Renewable by NREL(National Renewable Energy Laboratory s) of the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy by Midwest Research Institute RETSCREEN: developed by Natural Resources Canada's CEDRL with the contribution of 85 experts from industry, government and academia. HYBRID2: developed by NREL and the University of Massachusetts

12 13 Comparison between Modeling Tools

13 HES MODELLING WITH HOMER 14 Main features of HOMER:- HOMER s fundamental capability is simulating the long-term operation of a micropower system. Its higher-level capabilities, optimization and sensitivity analysis, rely on this simulation capability. The simulation process determines how a particular system configuration, a combination of system components of specific sizes, and an operating strategy that defines how those components work together, would behave in a given setting over a long period of time.

14 15 Schematic diagrams of some micro-power system types that HOMER models

15 HOMER Economics Analysis 16 HOMER uses the total net present cost (NPC) to represent the life-cycle cost of a system. The total Net Present Cost of a system is the present value of all the costs that it incurs over its lifetime, minus the present value of all the revenue that it earns over its lifetime. Costs include capital costs, replacement costs, O&M costs, fuel costs, emissions penalties, and the costs of buying power from the grid. Revenues include salvage value and grid sales revenue.

16 17 The NPC is calculated according to the following equation: Where: TAC is the total annualized cost (which is the sum of the annualized costs of each system component). The capital recovery factor (CRF) is given by: Where: N is the number of years and i is the annual real interest rate (%).

17 System Under Study 18 Site Selection Economic consideration, System constraints and control Net present cost calculations Demand load and resources Initial search space for system components Optimization technology, system components and sizing

18 Site selection 19 Remote Village in East of Owienat area N and E It is 340 km from the nearest Egyptian electricity grid line at Aswan City

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20 Electrical Load Demand Load kw Hours

21 22 Load demand

22 Renewable Energy Sources 23 Solar energy measured by kwh/m 2 /day Source: Egypt atlas

23 24 Wind energy measured by m/s Source: Egypt atlas

24 25 Source: NASA

25 26 Energy Resources

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27 28 search space

28 29 Economics consideration

29 30 System Control

30 31 Constraints

31 32 System Components

32 Simulation Results 33 Case I : Generator only Case II: Generator and PV Case III: Generator, PV and Wind turbine

33 34 Case I : Generator only

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35 36 The 11 possible results:-

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37 Discussion for Case I:- 38 In case I we can have 11 possible solutions. The optimum solution is to use two generators with 50% load sharing. The total NPC is $27,167,26.

38 39 Case II: Generator and PV

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43 Discussion for case II :- 44 In this case, we have 2 possible solutions. The optimum solution is to use the PV with 83% and the Diesel Generator with 17%. The NPC is $ 16,260,053.

44 45 Case III: Generator, PV and Wind turbine

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48 Discussion for case III :- 49 For this case, there are 6 possible solutions. The optimum solution is to use PV with 79 %, DG with 14% and WT with 7%. The NPC $ 14,518,144.

49 Results Discussion 50 These results are based on the available data, subject to the increase or decrease of the prices. Diesel generator fuel Transportation cost was considered in the fuel price (USD/Littre). Wind turbine with low cut-in speed was chosen to match the wind speed range in the selected site.

50 Conclusion 51 In this thesis, the world s energy problem was discussed, mentioning its main drivers (world s population, economic growth and energy prices). Hybrid energy system was presented explaining its applications, different configurations, advantages and disadvantages. HOMER software was chosen as the simulation tools for its great advantages over other programs.

51 52 Conclusion (cont.) A case study ( remote village at East of Oienate ) was chosen and simulation carried out based on the available load data and renewable resources data. The HOMER simulations results indicate that the use of hybrid energy source with the aid of available renewable resources (solar and wind) resulting in reduction of the NPC of the overall system from 27,167,26 (in case of diesel generators powered system) to 17,406,764 USD (in case of hybrid PV, wind, and diesel system)

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