Solar Panel Energy Simulation (C++)

A C++ simulation that models the hourly energy production of a small solar panel system over a 24-hour period.

The program demonstrates object-oriented programming concepts, smart pointers, random number generation and mathematical modelling using the C++ Standard Library.

Features

• Simulates a full 24-hour day.
• Models daylight using a smooth sine wave.
• Simulates changing weather with random cloud cover.
• Supports multiple solar panels.
• Calculates hourly energy production.
• Displays total daily energy generated.
• Uses std::unique_ptr for automatic memory management.

How It Works

Each SolarPanel object has a maximum power rating measured in kilowatts (kW).

For every hour of the day the program calculates:

Energy Output = Panel Power × Sunlight Intensity × Cloud Factor

Sunlight Intensity

Sunlight follows a sine wave:

• 00:00 – 05:59
  • No sunlight
• 06:00 – 18:00
  • Output increases until midday
  • Peaks around 12:00
  • Gradually decreases toward sunset
• 19:00 – 23:59
  • No sunlight

This creates a realistic daylight curve.

Cloud Factor

Weather is simulated using a random value between:

• 1.0 = clear sky
• 0.5 = heavy cloud

Each panel receives its own random cloud value every hour and creating natural variation in production.

---

Example Output

Hour | Energy Output (kWh)
--------------------------
   0 | 0.000
   1 | 0.000
   ...
   9 | 0.421
  10 | 0.592
  11 | 0.731
  12 | 0.782
  ...
  23 | 0.000

The Total Energy: 6.487 kWh

Since cloud cover is random and every output produces slightly different results.

Project Structure

main.cpp
│
├── SolarPanel class
│   ├── sunlightIntensity()
│   ├── cloudFactor()
│   └── output()
│
└── main()
    ├── Creates solar panels
    ├── Simulates 24 hours
    ├── Prints hourly production
    └── Prints total daily energy

C++ Concepts Demonstrated

This project demonstrates:

• Classes and objects
• Encapsulation
• Private helper functions
• Constructors
• Smart pointers (std::unique_ptr)
• Dynamic memory management
• std::vector
• Random number generation (std::mt19937)
• Mathematical functions (std::sin)
• Loops and iteration
• Formatted console output (iomanip)

Building

Compile using a C++17 compatible compiler.

GCC / MinGW

g++ -std=c++17 main.cpp -o SolarSimulation

Run

Linux/macOS:

./SolarSimulation

Windows:

SolarSimulation.exe

Customisation

You can easily modify the simulation:

Change the number of panels

panels.push_back(make_unique<SolarPanel>(0.4));

Add more panels by inserting additional lines.

Change panel size

SolarPanel(0.4)

Examples:

Rating	Description
0.30	300 W panel
0.40	400 W panel
0.55	550 W panel

Change weather conditions

Modify:

uniform_real_distribution<>(0.5, 1.0);

Example:

uniform_real_distribution<>(0.8, 1.0);

This simulates consistently sunny weather.

Possible Improvements

Future enhancements could include:

• Seasonal sunlight variation.
• Real sunrise and sunset times.
• Battery storage simulation.
• Solar inverter efficiency.
• Multiple weather profiles.
• CSV file output export.
• Monthly or yearly simulations.
• Real weather API integration (open-meteo).
• CSV file import instead of simulating it with sine wave (MIDAS Open (Met Office) or PVGIS).
• Graphical charts of power generation.

Learning Objectives

This project is intended as a beginner-to-intermediate C++ exercise covering:

• Object-Oriented Programming (OOP)
• Smart pointers
• Random number generation
• Mathematical modelling
• Clean code organisation
• Basic simulation techniques

License

This project is released under the MIT License. Feel free to use, modify and learn from it.