Smart Grids

Techno-Economic Analysis of a Microgrid

For this practical task we focus on Techno-economic analysis and comparing different scenarios in connecting renewable energy resources at distribution level for residential consumers. The software used for this task is HOMER (Hybride Optimization of Multiple Energy Resources) and it will the basis to optimize and evaluate solutions on utilizing Distributed Energy Resources (DERs) within the context of the smart grid paradigm.
To avoid complexities related to the system dynamics and smart grid infrastructures are not modelled in this software. However, analysis corresponding to utilization of DERs in designing
microgrid or residential energy systems can be simulated and evaluated with HOMER. For more technical details you can visit the link at:

Scenarios:
To start the analysis there are 3 different scenarios defined which have been represented through figures 1 to 3. As it is shown the schematic diagram for each scenario represents connection of
different types of Generation units (Diesel, Wind, PV and Battery Storage). The sizing for DERs are selected from the model provided in the HOMER software. In the following some of the information and requirements to use for this task have been listed in bullet points.
• Electricity bill of a household for one year.
• Current bank interest rate for a small business.
• Current inflation rate of Australia.
• HOMER installed in a computer.

Review the schematic diagram for all the 3 scenarios and continue the task by following steps provided in general procedure section.

General Procedure:
Step 1: Open HOMER software (click Start>All Programs>Homer Pro).

Step 2: Start New Project
add your name and describe your project according to the model (Green Rectangle) (Example: Figure 1, a stand -alone model with Diesel Generator as the source)

Step 3: Enter the address in the Location bar and search for the location. Ex: Footscray Park, Melbourne, Australia. (Red Rectangle)

Step 4: Enter the current Interest rate from the bank and inflation rate. (Orange Rectangle)

Step 5: Enter Click the Load from the tab and select Residential in profile and OK. (Red Rectangle)

Step 6: From the electricity bill for 1 year, calculate the electricity consumed per day by dividing 365 and enter that value in scaled average. (Red Rectangle)

Step 7: Under components, select Generator, in the dropdown box choose Auto size Genset (Gree Rectangles) and Add Generator (Red Rectangles).

Step 8: On clicking the Gen icon (Green Rectangle) in the Schematic, in the bottom, click on the fuel tab (Red Rectangle) to add the price of the Diesel (current price).

Step 9: In the icon under the schematic, click $(economics)-Red Rectangle- and choose Australian Dollar as currency (Green Rectangle). Click Calculate (Orange Rectangle) to get the optimised re- sults.

Step 11: Analyse the results by clicking the Optimised (Red Rectangle) results that is generated.

Step 12: Save the results by saving the project as Model1

Question 1:
Comment on the optimised setup HOMER creates from the NPC and cash flows.

Duplicate the above steps for Model2 and continue as below:

Step 1: From the components tab remove the Generator which was added and add
• PV (Generic flat plate)
• Converter
• Wind turbine
• Grid
For PV, Converter and wind turbine on the search space click on each option (PV, Converter and wind turbine) to optimise the size of the setup with upper to 500 and
lower 0 (Red Rectangle).

Step 2: Calculate the bill amount paid for a year and energy consumed for a year from the bills to calculate the price paid from the electricity purchased from grid.

Step 3: Under the resources from the tabs above

- Click Solar GHI and Download from internet (the solar radiation input at a given place)
- Click on the Wind resource and Download from internet(to get the wind resource at a given place)

Step 4: Click on Calculate to get the optimised results.

Question 2:
Comment on the optimised setup HOMER creates from the NPC and cash flows

Question 3:
Is the electric demand met using this model?

Question 4:
What is the use of Grid presence in this model?

Step 5: Save the project as Model2.

Duplicate the model to call it as Model3

Step 1: Now remove the grid from the schematic and add the Storage>Batteries>Generic>Ge- neric 1kWh Li-Ion battery.

Step 2: Click on Calculate to get the optimised results.

Question 5:
Comment on the optimised setup HOMER creates from the NPC and cash flows.

Question 6:
Is the electric demand met using this model?

Question 7:
What are the advantages or disadvantages of using battery in this model?

Your report should address and discuss following:
• Answer the questions Q1-Q7 included for all the three models in the General Proce- dure section
• Understand the results of the optimised setup for all the three models by the cash flow analysis given by HOMER.
• Compare the NPC (Net Present Cost) for all the three models to understand the economi- cally viable set up by plotting the graph of NPC vs the setup.
• Analysis of environmental impact for the three models created (by plotting the graphs of the gases that each system released to the surroundings).
• Provide comments or suggestions if the three models have to become practical according to smart grid operation environment.
• Self-reflect on the below points:
a) What problems have I encountered in this project?
b) How have I analyzed, evaluated, and developed solutions to these problems?
c) Have I used any creative or innovative approaches to solve these problems?