1. Effect of Diesel Generator Characteristics on the Design Optimization of a Stand- alone Hybrid Micro-power System for Baghdad City
By Dr. Sameer Saadoon Algburi Dr. Amer Mejbel Ali Al-KITAB University College Al-Mustansiryah University Kirkuk ,IRAQ Faculty of Engineering BAGHDAD , IRAQ

2. What is HOMER?
HOMER is the global software for micro grid optimization. Avoid costly mistakes by focusing on optimal hybrid power systems that meet needs.
Village power systems
Stand-alone applications
Grid-connected systems
Conventional technologies
New technologies

3. HOMER work with renewable technologies
Solar PV
Wind
Biomass and biofuels
Hydro

4. Questions HOMER can Answer
Should I buy a wind turbine, PV array, or both?
Will my design meet growing demand?
How big should my battery bank be?
What if the fuel price changes?
How should I operate my system?
And many others…

5. Aim of this work
The main object of this work is to study the effects of diesel generator characteristics on the design optimization of stand-alone micro-power system include renewable energy power sources from wind turbine and solar panels with diesel generator in Baghdad city.

6. The proposed load profile for this work is shown in figure below, is for stand-alone (off-grid) village in Baghdad city. The average load is 745 kWh/d, and peak power is 104 kW.

7. Solar data can be loaded from NASA web site by pressing (Get Data via Internet) in HOMER ,as shown in figure below for Baghdad city ( 33° 20' North, 44° 23' East )

8. The average monthly wind speed in meter per second for Baghdad city is taken from weather-and-climate.com, and implemented in HOMER simulation as in figure below.

9. Optimization cases
HOMER software was implemented to study the effects of diesel generator characteristics (loading ratio, life time, fuel consumption ,and fuel type) on the design optimization of a hybrid micro- power systems for Baghdad city.

10. Case 1: Effect of diesel generator loading ratio on system design optimization
Four simulation process were implemented by changing diesel generator loading ratio to 25%, 50%, 75% and 100%, and fixing generator life time (15000 hrs) and fuel consumptions (0.3 L/hr/kW)

11. Case 2 : Effect of diesel generator life time on system design optimization
One of each of the three values of diesel generator life time (5000, 10000, hrs) were used in simulation by fixing generator loading ratio (25%) and fuel consumption (0.3 L/hr/kW).

12. Case 3: Effect of diesel generator fuel consumption on system design optimization
Three simulations were performed by HOMER for fuel consumption of 0.3, 0.4 and 0.5 L/hr/kW when fixing generator life time on hrs and generator loading ratio at 25%.

13. Case 4: Effect of diesel generator fuel type on system design optimization
Four types of fuel (diesel, methanol, ethanol, natural gas) were taken into account when studying the effect of fuel type on system optimization while fixing generator life time, loading ratio, and fuel consumption

14. OPTIMIZATION RESULTS DISCUSSION
HOMER selects the lower cost combination of hybrid system components to achieve optimization along 25 years of system life time . The lower cost system design is achieved at 50% of diesel generator loading ratio in the proposed hybrid system. The effect of increasing generator life time is reducing net present cost(NPC ). The optimization is reached when we use diesel generator at lower fuel consumption. The best economically generator fuel type is natural gas since it gives lower NPC . The optimization results obtained in this work show the contribution of solar and wind energies in producing electricity in the proposed hybrid micro-power system is very low and reach to zero percent in case of 100% generator loading ratio due to low wind speed in Baghdad city and high cost of PV system .

15. CONCLUSIONS
1-The design optimization of hybrid off-grid micro-power system for Baghdad city were investigated using HOMER software taking into account the characteristics of diesel generator including generator loading ratio ,life time, fuel consumption and fuel type.
2-The optimization were achieved (lower life time cost) when the diesel generator has higher life time, lower fuel consumption with using natural gas.
3-The participation of renewable energies of wind and sun is low in proposed system due to economical and environmental considerations.
4- System designers should take generator characteristics into account when planning any hybrid micro-power systems.