How To Get 12 Volts From a 24 Volt System

Off-grid solar power systems often operate at higher voltages like 24VDC for efficiency reasons, especially in systems with significant power demands or long cable runs.

Understanding the Need for Conversion

1. Efficiency in Solar Systems: Higher voltage systems (like 24V and 48V) reduce energy loss over long distances, making them preferable in off-grid setups. These systems are also cheaper to make. Read my article about 12V VS 48V.
2. Compatibility with Devices: Many off-grid applications, particularly in RVs, boats, or remote cabins, use 12V appliances (lights, pumps, electronics).

Converting from 24VDC to 12VDC is a common requirement in these systems. Here’s an overview of how this can be achieved effectively:

Buck Converter (Generic)

1. Functionality:
   • A buck converter is a type of DC-DC converter that steps down voltage from a higher level (24V) to a lower level (12V) while attempting to maintain efficiency.
   • It works by switching a transistor on and off rapidly, controlling the time the voltage is applied to an inductor.
2. Cost-Effectiveness:
   • Generally, buck converters are more affordable than specialized brand-name converters.
   • They are a go-to choice for budget-conscious setups or DIY projects.
3. Efficiency:
   • These converters can be quite efficient, often above 90%, depending on the quality and design.
   • Efficiency may vary under different load conditions.
4. Limitations:
   • Generic buck converters might lack advanced features like overcurrent protection, thermal shutdown, or voltage regulation under varying load conditions.
   • The build quality can vary significantly between different manufacturers.

Victron DC-DC Converter

1. Brand Reputation:
   • Victron Energy is known for its high-quality power conversion and energy storage solutions, widely used in off-grid solar systems.
   • Their DC-DC converters are designed specifically for demanding applications.
2. Features and Reliability:
   • Victron DC-DC converters offer stable output voltage, high efficiency and are built to handle fluctuating loads effectively.
   • They often include advanced features like over-voltage protection, over-temperature protection, and overload protection.
3. Integration with Solar Systems:
   • Victron converters are designed to integrate seamlessly with other Victron components, making them ideal for systems already using Victron products.
   • They often support monitoring and control via Victron’s system management tools.
4. Cost:
   • Victron converters are typically more expensive than generic buck converters.
   • The build quality, reliability, and additional features justify the higher price.

What is the difference between the Victron Orion and the Victron Orion-TR smart?

Victron Orion Standard

• Function: Basic DC-DC conversion.
• Controls: Physical adjustment controls for voltage and current.
• Connectivity: No remote monitoring or control.
• Use Case: Best for simple, set-and-forget applications where constant output voltage is needed.

Victron Orion-Tr Smart

• Function: Advanced DC-DC conversion with similar core functionality.
• Controls: Remote adjustment via Bluetooth and a dedicated app.
• Connectivity: Enables remote monitoring and control, providing real-time data and alerts.
• Use Case: Ideal for complex systems requiring frequent adjustments, monitoring, and integration with smart systems and car alternators.

Key Differences

• Smart Features: Orion-Tr Smart offers Bluetooth connectivity for remote control and monitoring, unlike the standard Orion.
• User Interface: The Smart version allows for easier and more precise adjustments through an app.
• Price: Orion-Tr Smart is typically more expensive due to its advanced features.

Choosing Between the Two

1. Budget Considerations:
   • If cost is a primary concern and the application is relatively simple, a generic buck converter might suffice.
   • For critical applications or where additional features are needed, the Victron converter is a better choice.
2. System Compatibility:
   • For systems already equipped with Victron products, their DC-DC converter will ensure compatibility and ease of integration.
   • In standalone applications or as part of a diverse set of components, a generic buck converter can be a practical choice.
3. Load Requirements:
   • Evaluate the power requirements of your 12V devices. Ensure the chosen converter can handle the maximum current draw.
4. Durability and Longevity:
   • Consider the environmental conditions and operational demands. Victron’s products are known for their durability in harsh conditions.

Conclusion

The choice between a generic buck converter and a Victron DC-DC converter in an off-grid solar system largely depends on budget constraints, system integration needs, and the importance of reliability and advanced features. While Victron offers high-quality, feature-rich products, generic buck converters can be a cost-effective solution for simpler, less demanding applications.