1. In the name of God

2. Optimal Sizing of a Stand-alone Wind- Photovoltaic Hybrid System for Supplying a Remote Intermittent Load Considering the System Reliability and Using Firefly Algorithm Asghar Gholami MSc in power engineering- energy management Amirkabir University of Technology (Tehran Polytechnic) Amirkabir University of Technology (Tehran Polytechnic) A.Gholami asghargholami87@gmail.com

3. Introduction Hybrid systems of renewable energies suitable candidate for supplying power Why? Title, Writer(s) complementary effect of renewable energies more reliability less cost renewable energies are not used extensively especially in developing countries why? Answer : Affordability How we can improve it ? Optimal Sizing

4. Briefly : minimize cost Considering  more details  algorithm with more accuracy and speed  reliable reliability factor Title, Writer(s) Objectives

5. Theoretical hybrid energy system

6. 8760 h –load (draw water from well ) 5 8760 h – solar radiation 8760 h – wind speed

7. The problem objective (Ppv) Rated Power 4772.7 US$/kw Cost of each kW CC pv 40 v MPP Voltage 43.8 US$/unit- year Annual Cost of Maintenance MC pv 6A Current in MPP 20 year Lifetime 7A Short Circuit Current 4% Rate of Emergency Power Off The problem objective (P wind ) Rated Power <20% of the rated power output power in High cut off speed 110 ac-125 dc PMSG Rated Voltage 2000 US$/kw Cost of each kW C Cwind 2.5 m/s V cutin 175.2 US$/unit-year Annual Cost of Maintenance MC wind 14m/s-9 depending on the outpit power V rated 20 yearLifetime 25m/s V cutout 4% Rate of Emergency Power Off TABLE II. WIND TURBINE CHARACTERISTIC TABLE I. PV PANEL CHARACTERISTICSTABLE III. BATTERY CHARACTERISTICS The problem objective Max Capacity 80.95 US$/kwh Cost of each kWh CC bat 2kwh Min Capacity 93US$/kwh Replacement Cost 4 year Lifetime Negligible Annual Cost of Maintenance MC bat 70% efficiency η bat %0%0 Rate of Emergency Power Off η mppt=0.95 MPPT Efficiencyir=0.06Interest rate 37 deg The angle of PV panel R=20Lifetime η inv =0.9 The inverter efficiency CRF=0.5872 Capital Recovery Factor Assumed Negligible Rate of Emergency Power Off of the inverter K bat =1.574 The constant current value factor TABLE IV. EXTRA BATTERY CHARACTERISTICS

8. Review  2013 Publisher :IEEE  Subho Upadhyay M. P. Sharma.  energy system for off-grid application. Energy Efficient Technologies for Sustainability.  LINGO software and MATLAB optimization toolbox have been used for the optimization problem  the optimized are derived.  Limitation of lingo : Limitation the number of Constraints.

9. Review  2005  M.J. Khan, M.T. Iqbal,  “Pre-feasibility Study of Stand-alone Hybrid Energy Systems for Applications in Newfoundland”.  HOMER - Hybrid Optimization Model for Electric Renewables.is used as a sizing and optimization tool.  For implementation in HOMER, 8760 data points for each hour in 1 year is required.  If data is not enough what we should do ?  Although in offline optimization problems, time is of less importance, in some cases such as the issue time will be important.

10. Review  2008  S. Kishore Kumar, Abha Rajoria, E.Fernandez  “Reliability Assessment of Wind-Diesel Hybrid System”,  Various reliability criteria such as Loss of Load Expectation (LOLE), Loss of Energy Expectation (LOEE), which is equivalent to Expected Energy Not Supplied (EENS) as well as Loss of Power Supply Probability (LPSP) has been evaluated.  the criterion of Equivalent Loss Factor (ELF) that contains information of the number and duration of outages is rather more precise compared to the other criteria.  Is really its always true?

11. Review  2009  Kashefi Kaviani, A. Riahy, G. H. Kouhsari, Sh M.  “Optimal design of a reliable hydrogen-based stand-alone wind/PV generating system, considering component ’’  certain size of wind turbine or PV array is chosen and the optimization results determine their required number and the amount of their generation in each hour.  the problem is converted to a discrete problem and although it leads to fewer calculations, for small powers does not have the required accuracy.  This means that the constraint of the system reliability can be met with lower costs

12. Review  2014  Pirhaghshenas vali, Asaei,  Optimal modeling and sizing of a practical hybrid wind/PV/diesel generation system  The stand-alone system is designed based on the local data of solar radiation and wind speed along with operation states for system load in 24 hours.  particle swarm optimization (PSO) is a suitable tool for optimal sizing of a hybrid system with uninterrupted loads.  Is there any better way? For Discreeted loads what happen ?

13. Methodology Of Research Title, Writer(s)

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15. Objective Function CC is constant capital cost, MC is Maintenance cost, RC is replacement cost. constraints include 2.Reliability 8760 number 1.the limitation of the battery 8760 number 3. Max variable

16. ELF depends on the hours H. This causes ELF to change with the change of the duration of study. so smaller ELF does not always assure a better reliability.To address this issue, the no-load hours of the system are not considered If H modifies to the hours in which there is load in the system. This makes the reliability in no-load supply to be 1, and the ELF less than 1 ensures reliable reliability. We call it ELF new and assum.

17. Firefly Algorithm

18. 1.a number of artificial fireflies are randomly distributed in the permissible range of the problem. 2. every firefly emits some light with the same intensity that is proportional to the amount of optimal point that firefly is located there. 3.the intensity of the light of every firefly is regularly compared with the intensity of the light of the other fireflies and less bright fireflies are absorbed by the brighter fireflies. 4. Meanwhile, the brightest firefly randomly moves into the allowable range of the problem aimed at increasing the chances of finding the global optimum solution of the problem.. 2008, by Xin-She Yang for the first time

19. move the ith firefly toward the jth firefly r ij is the Euclidean distance β is the maximum attractiveness factor α is a random displacement vector factor

20. Title, Writer(s) THE OPTIMAL SIZE OF THE SYSTEM WITH THE MINIMUM ANNUAL COST OF $6786 BatteryWind turbinePV panel 59.5kwh0.5 kw11.5 kw Using multi objective method

21. Summary of Findings Title, Writer(s)  The ELF criterion ensures the system reliability, especially for discrete loads  Several meta-heuristic algorithms are surveyed in this paper and the results are compared.  The optimization results prove the efficiency of firefly algorithm in terms of simplicity in implementation, more accuracy and speed, compared to GA, PSO and APSO.  According to No Free Lunch (NFL) theorem, if in search of extreme of a cost function, algorithm A exceeds algorithm B, then for the other cost functions, algorithm B will be prior to algorithm A. In other words, is not necessarily superior to the other algorithms in different problems

22. Proposal Guidelines Title, Writer(s)  Various hybrid systems can add to system  Connection on grid  Using fuzzy logic controller for battery charge and discharge  Using more data is take use better answer?  Optimization whit considering real time electricity marketing to maximize benefit of selling power to grid and minimize cost.