What is a Dual Speed Compressor?
Previously, screw compressors were categorised into two main groups: fixed speed and variable-speed drive (VSD). But in 2023, Atlas Copco introduced the first dual-speed rotary screw compressor.
Atlas Copco’s dual-speed technology bridges the gap between fixed-speed and VSD compressors, offering flexibility and energy savings at an affordable cost.
This article explains what a dual-speed compressor is.
A dual-speed screw compressor runs at two different speeds. Like fixed-speed compressors, one of the speeds gives maximum compressed air output when needed. But it also has a lower speed when the demand for air reduces.
The GA FLX series by Atlas Copco employs advanced dual-speed technology that minimises transient energy losses and optimises performance across varying air demands.
Discover the GA Series of air compressors
Compressor Types
Compressed air systems are crucial in various industries, and choosing the right compressor type is essential for optimal performance and energy efficiency.
There are three primary types of compressors:
- fixed-speed
- dual-speed
- variable-speed
Each type has unique characteristics, advantages, and disadvantages.
Fixed-speed air compressors operate at a single speed, providing a constant output of compressed air. They are straightforward and reliable but can be inefficient due to continuous on/off cycles consuming more energy during periods of low air demand.
On the other hand, dual-speed air compressors offer two speeds: a high speed for maximum air output and a low speed for reduced energy consumption. This flexibility delivers substantial energy savings.
Variable-speed air compressors are the most advanced and can match their speed to the demand for air in real time – this precise control over motor speed results in optimal energy efficiency.
What is a Dual-Speed Compressor and How Does it Work?
A dual-speed compressor is the perfect solution for businesses looking for compressor energy savings but not ready yet for a variable speed option. It operates at two distinct speeds, automatically switching between full capacity when compressed air demand is high and reduced speed when air demand is lower.
Unlike traditional fixed-speed models, which run at 100% capacity or shut off completely, dual-speed compressors reduce energy losses incurred during frequent start-stop cycles. This means less wasted energy and lower operating costs. The Atlas Copco GA FLX series uses advanced dual-speed technology to optimise air output, minimise unload losses, and ensure steady airflow without excessive wear.
By adapting to operational phases, a dual-speed compressor reduces transient energy losses. It produces usable air more efficiently, making it cheaper to operate than fixed-speed models while offering significant savings on energy costs. It is the ideal middle ground for many businesses.
Benefits of Dual-Speed Compressors
- Energy savings: operate at two speeds to match air demand, cutting energy costs.
- Reduced losses: unlike fixed speed models, they minimise energy waste by slowing down during low demand.
- Flexible pressure: adjust pressure settings without losing airflow, potentially using smaller-sized compressors.
- Lower maintenance: less wear on parts means fewer repairs and a longer lifespan.
- Cost-effective: balance between efficiency and cost, great for changing air needs.
Energy savings
Dual-speed air compressors save energy by adapting their motor speed to match the air demand. When the demand for compressed air is high, they run at full speed, delivering the necessary air output. But when the demand drops, the compressor slows down, reducing energy consumption. By using only the energy needed, dual-speed compressors lower energy bills. By using only the required energy, dual-speed compressors like the Atlas Copco GA FLX lower energy costs by up to 20% compared to fixed-speed models.
Lower transient losses
A dual-speed compressor tackles these issues by starting against pressure and using less energy to produce air. The Atlas Copco GA FLX 11-30 model is engineered to deliver optimal flow at different pressures, ensuring efficient air delivery while consuming less energy. It minimises blow-off losses by not venting as much air as a fixed-speed air compressor. Additionally, it runs at a lower motor speed while unloading. A dual-speed air compressor can save 20% more energy than a fixed-speed model. Atlas Copco’s GA FLX 11-30 model minimises blow-off losses and consumes significantly less energy when running at reduced speeds, enhancing overall efficiency.
Multiple pressure settings
Another benefit of a dual-speed compressor is that, unlike other fixed-speed compressors, you can choose any pressure without compromising air flow or free air delivery (FAD). This means it can run efficiently at multiple pressure set points. This flexibility might allow you to choose a smaller dual-speed compressor instead of a fixed-speed one and save on capital and operational costs. This flexibility enables operators to match output to operational requirements, potentially using smaller compressors to achieve the same results, reducing capital and operating expenses.
Less maintenance
Dual-speed air compressors lower maintenance costs because the motor speed adapts to demand, reducing strain on components. By slowing down during low air demand, they experience less wear and tear, leading to fewer repairs. This flexibility helps extend the compressor’s lifespan, saving operators money on maintenance. Atlas Copco’s dual-speed models include predictive maintenance systems like SMARTLINK to reduce downtime and ensure optimal performance.
Cost-effective
Dual-speed compressors provide cost savings by lowering energy use during periods of low air demand and minimizing maintenance requirements, resulting in long-term savings despite a higher initial cost. While the initial investment is higher than fixed-speed models, dual-speed compressors often achieve a payback period within two years through energy and maintenance savings.
Comparison of Different Air Compressor Types
Here is a quick comparison of single-speed, double-speed, and variable-speed drive (VSD) compressors.
| Type of Compressor | Pros | Cons | Unique Features | Benefits |
| Fixed-Speed (Single-Speed) | Most affordable initial investment cost Simple operation | High energy waste during off-load periods Inefficient due to continuous on/off cycles | Run at 100% capacity when loaded Consumes 35% of energy when off-load without producing air | Suitable for applications with consistent air demand |
| Dual-Speed | More energy efficient than single-speed Reduces off-load energy use by 20% Fewer parts, reducing maintenance issues | Higher initial cost than fixed-speed May not save much energy if air demand is stable or used in short bursts | Can slow down to minimum speed and off-load to conserve energy | Energy savings over time with a payback period of around two years Ideal for varying air demand |
| Variable-Speed | Highly energy-efficient Adjusts motor speed to match air demand Lower wear on internal parts | Highest initial purchase cost Only cost-effective for operations with fluctuating air demand | Modulates speed between 20% and 100% capacity to match air demand | Significant long-term energy savings ROI under 6 months Operates like a dimmer switch for air pressure control |
Atlas Copco’s dual-speed compressors combine energy efficiency with operational flexibility, making them a practical solution for many industries.
Dual-Speed vs Variable-Speed Compressors
Both dual-speed and variable speed compressors offer energy savings but suit different needs.
- Dual-speed compressors, like the first dual-speed compressor from Atlas Copco UK, switch between two preset speeds, reducing transient energy losses and lowering energy costs compared to a fixed-speed GA compressor. They are cheaper to operate and ideal for moderate fluctuations in compressed air demand.
- Variable speed compressors (VSD), such as the GA VSD series, continuously adjust output between 20% and 100% capacity. They offer maximum efficiency with fewer unload losses but are much more expensive.
A dual-speed compressor is the perfect solution if you are looking for compressor energy savings but are not yet ready for a variable speed investment. However, a VSD compressor remains the most cost-effective long-term option for operations with highly variable air demand.
Why You Will Love the GA FLX
- 20% energy saved
- Reduces total operating costs
- Variable pressure settings without sacrificing airflow
- 50% smaller footprint than GA fixed speed
- Custom performance settings
- Atlas Copco’s reliability, quality, and energy efficiency
Atlas Copco’s GA FLX compressors minimise transient losses, operate efficiently under pressure, and deliver reliable performance for diverse applications.
The GA FLX dual-speed compressor cuts down on energy waste, known as transient losses. What are transient losses? These are energy losses that occur when a fixed-speed compressor starts and stops. A fixed-speed compressor can waste 20% of energy because of these losses, as it has to run at a minimum speed even when not producing air. The GA FLX can start up quickly under pressure and minimises energy losses thanks to its advanced technology.
Applications of Dual-Speed Compressors
Manufacturing
For factories where air requirements change throughout the day. They adjust speed to match needs, save energy, and keep operations running smoothly.
Automotive
A reliable and efficient air supply in vehicle assembly lines for tools that need varying air pressure.
Healthcare
In hospitals, where medical equipment needs a constant air supply, they adjust to keep the correct pressure to ensure the smooth running of critical medical devices.
Food and Beverage
Clean, dry air is critical in food production. Dual-speed compressors meet these demands by adjusting to changing air requirements and guaranteeing safe and efficient processes.
Construction
Dual-speed air compressors provide better tool performance and energy savings on site by adjusting speed to the task.
Choosing the Right Compressor
Choosing the right compressor means weighing energy efficiency, cost, and air pressure needs. Variable-speed compressors are the most energy-efficient but cost more upfront. They are ideal for jobs with changing air demand since they adjust speed to match output needs.
Dual-speed compressors strike a balance between efficiency and cost. They save more energy than fixed-speed models and work well for varying air demands. Though pricier than fixed-speed compressors, they often pay for themselves quickly through energy savings.
Fixed-speed compressors are the least efficient but cheapest. They are best for consistent air demand, running at full capacity without frequent stops.
Speak with Control Gear experts to find the right balance between performance, efficiency, and cost for your operations.
Need help? Speak with one of our experts to find the right balance of performance, efficiency, and cost.
Design and Installation Considerations
Consider these key points for top performance and efficiency when setting up a compressed air system.
Make sure the compressor goes in a well-ventilated spot to avoid overheating and extend its life. Proper ventilation keeps the compressor cool and running smoothly.
Design the piping system to reduce pressure drops and maintain optimal air delivery at every pressure set point. Choose the right materials and sizes for efficient airflow.
Regular maintenance is crucial. Replace air filters, check oil levels, and clean components to keep the compressor in good shape. Scheduled maintenance prevents breakdowns and ensures efficiency.
Control Gear technicians offer expert design, installation, and maintenance services to maximise the performance of your compressed air system.
Dual-Speed Compressors – Saving Energy Without Breaking the Bank!
This article explained what a dual-speed compressor is. This completely new compressor type offers many benefits, with energy savings being the most significant. Contact our experts at Control Gear to discuss Atlas Copco compressors.
FAQ
How does a dual-speed compressor compare to a fixed-speed GA compressor?
A dual-speed compressor is the perfect solution if you want to reduce energy costs but are not yet ready for a variable speed investment. Unlike a fixed-speed GA compressor, which runs at 100% capacity or switches off completely, a dual-speed model adjusts between two speeds to match demand, reducing unload losses and improving efficiency.
What happens when a compressor goes into unload?
When a compressor goes into unload, it continues to consume energy but produces no compressed air, leading to wasted energy and higher costs. A dual-speed compressor minimises this by slowing down instead of fully unloading, making it a more efficient alternative to fixed-speed models.
Is a dual-speed compressor the right choice if I have fluctuating air demand?
A dual-speed compressor is the perfect solution if your business experiences moderate fluctuations in air demand. It houses two compressors that switch speeds to balance efficiency and cost savings. However, if your air demand varies significantly, you might need to consider a variable speed option.