Satellite Power Systems: Solar Arrays, Batteries, and Energy Storage

Satellites orbiting Earth and exploring the farthest reaches of space rely heavily on advanced power systems to operate effectively. These power systems provide energy to all satellite components, from communication systems and scientific instruments to attitude control systems and propulsion. Selecting the appropriate power source for a satellite is one of the most critical engineering decisions, as the success and longevity of a satellite depend on reliable and efficient power. In this article, we’ll explore the various power sources for satellites, including solar arrays, batteries, and energy storage systems, and their importance in modern space technology.

The Role of Power Systems in Satellites

Satellites are designed to operate autonomously in space for extended periods, often in extreme environments with no external support. Their power systems ensure that they can perform their intended functions, such as transmitting data, controlling their orientation, or operating scientific instruments, regardless of their position relative to the Earth or the Sun.

Key Functions Supported by Satellite Power Systems:

The power system design for any satellite typically consists of three primary components:

Solar Arrays: The Primary Power Source for Satellites

The vast majority of satellites use solar arrays as their primary power source. Solar arrays consist of photovoltaic (PV) cells that convert sunlight into electrical energy, which can then be used to power the satellite’s systems or be stored for later use. Since satellites in orbit receive direct sunlight for long periods, solar power is the most reliable and sustainable energy source for long-term missions.

Why Solar Arrays Are Critical for Satellites:

Types of Solar Arrays:

Notable Solar Power Satellites:

Batteries: Energy Storage for Satellites

Although solar arrays are the primary power source, batteries play a crucial role in satellite power systems by storing energy for use when the satellite is not exposed to sunlight. For instance, during the eclipse periods when a satellite passes through Earth's shadow, it relies on its batteries to continue functioning.

Types of Batteries Used in Satellites:

Importance of Batteries in Satellite Systems:

Notable Examples of Satellite Batteries:

Energy Storage Systems: The Future of Satellite Power

With advances in energy storage technology, new methods are emerging that could revolutionize how satellites store and utilize power. Supercapacitors and radioisotope power systems (RPS) are being explored as alternatives to traditional batteries for their ability to store and discharge energy rapidly and operate in extreme conditions.

1. Supercapacitors:

Supercapacitors are capable of charging and discharging energy much faster than traditional batteries. While their energy density is lower than that of Li-ion batteries, their quick response times and longevity make them suitable for specific applications, such as providing short bursts of power for certain satellite operations.

2. Radioisotope Power Systems (RPS):

RPS, commonly used in deep space missions like Voyager and New Horizons, convert heat from the decay of radioactive materials (typically plutonium-238) into electricity. These systems are ideal for missions far from the Sun, where solar energy is insufficient for power generation.

Emerging Energy Storage Technologies:

Power Management and Distribution

Beyond energy generation and storage, satellite power systems require efficient power management and distribution (PMAD) systems. These systems regulate the flow of power between the solar arrays, batteries, and onboard systems, ensuring that the satellite operates efficiently.

Key Functions of PMAD Systems:

Power systems are the lifeblood of artificial satellites, enabling them to function in space for years or even decades. Solar arrays are the most widely used power source, providing continuous energy generation. Batteries, especially Li-ion and Nickel-Hydrogen batteries, ensure reliable energy storage during eclipse periods or when sunlight is unavailable. As technology advances, energy storage systems like supercapacitors and radioisotope power systems will play an increasingly important role in the future of satellite power systems.

The evolution of satellite power technology continues to shape the future of space exploration, communication, and scientific discovery. By understanding these key systems, we gain insight into the engineering marvels that make modern satellite technology possible.

Recommended products for building a satellite

If you're planning to build a satellite at home, here are some top products you can purchase online to get started with a small satellite project, like a CubeSat:

These products, along with open-source satellite kits, can give you a solid foundation to design and assemble a small satellite for educational or hobbyist purposes!

Building a fully functional satellite using the listed products is an exciting and complex project. Here's a step-by-step guide to help you assemble these components into a working satellite, such as a CubeSat:

Step 1: Define Your Satellite’s Mission

Before assembly, decide what your satellite will do. Whether it’s Earth observation, communication, or scientific experiments, defining the mission will help you choose the right sensors and equipment.

Step 2: Build the CubeSat Frame


Step 3: Design the Power System


Step 4: Set Up the Onboard Computer


Step 5: Attach Sensors and Modules


Step 6: Communication System


Step 7: Write and Upload the Software


Step 8: Testing and Simulation


Step 9: Launch Preparation


Step 10: Launch and Operate

Building a satellite at home is an ambitious yet achievable goal for hobbyists, engineers, and students. With these components, proper planning, and the right mission objectives, you can contribute to space research and innovation right from your home.