On-Demand Nitrogen vs. Storage Systems

Watch our Sale Engineer Breakdown the Difference Between the Two

When you need nitrogen for laser cutting operations, the choice between on-demand nitrogen generation and high-pressure storage systems can greatly impact your bottom line, efficiency, and scalability. Both give you independence from bulk nitrogen suppliers. However, on-demand nitrogen stands out for its efficiency, lower total cost of ownership, and greater flexibility to grow with your facility.

Explore how these systems differ, the hidden costs of storage, and the benefits of on-demand nitrogen systems for your business.

Understanding the Two Approaches 

The laser cutting industry currently offers two main approaches to provide nitrogen on-site: 

High-Pressure Storage Systems

The storage system model relies on “banking” gas. It provides nitrogen, often during off-peak hours or continuously at a lower flow rate, and then feeds it into a high-pressure booster. The booster compresses the gas to an extreme 4,500 pounds per square inch gauge (psig) and pushes it into large banks of storage cylinders.

When your laser cuts, it draws from the high-pressure reserve, regulated down to the required cutting pressure. The theory is that you can use a smaller generator that runs 24/7 to fill the bank, instead of matching peak demand. 

On-Demand Generation Systems

On-demand generators provide laser-grade nitrogen in real time as needed. They usually operate at a mid-pressure range of 450 psig, the exact pressure required for most high-speed fiber laser cutting applications.

These systems scale generation capacity to match your peak demand. There is no massive high-pressure bank to fill and manage, saving you storage space and time while delivering nitrogen exactly when and where you need it. 

The Hidden Costs of High-Pressure Storage 

Storage system vendors usually market them based on the smaller size of the nitrogen generator component. However, this overlooks the operational and capital costs of the storage infrastructure itself. When you look at the total cost of ownership, the storage model can have many hidden expenses:

1. High-Pressure Equipment Requirements

Compressing gas to 4,500 psig is costly. The equipment, operational, and maintenance costs for high-pressure storage systems add up:

• Equipment costs: High-pressure boosters are complex and expensive pieces of machinery. The capital cost of this equipment is often significantly higher than the standard mid-pressure compressors used in on-demand systems.
• Operational costs: Compressing air and gas takes a lot of energy, often leading to higher electricity costs to push the nitrogen from standard pressures up to 4,500 psig than compressing it to 450 psig needed for laser cutting. You essentially pay to pressurize gas to levels you will never use, only to regulate it back down at the laser nozzle. 
• Maintenance costs: High-pressure boosters withstand immense mechanical stress. The annual maintenance costs add up as a result, with shorter service intervals, frequent maintenance, specialized parts, and certified technicians needed to service these systems.

2. Complex Cylinder Management

Storage systems require banks of high-pressure cylinders to hold the gas reserve. These banks take up valuable floor space, usually hundreds of square feet, that you could be using for production or material handling. 

Safety is another big concern. Handling vessels pressurized to 4,500 psig introduces significant risk in the workplace. These systems require strict inspections, handling, and storage protocols. Your facility must invest in specialized training for personnel and follow rigorous safety audits, adding more hidden labor hours to your overhead. 

3. Inflexibility for Production Changes

High-pressure storage systems are rigid by design. They are sized based on the assumption that your duty cycle and daily consumption will be consistent. If your business grows, however, and you need to add a second shift or purchase a high-power laser, the storage system will fail to keep up. Expanding a high-pressure system is complex, requiring you to replace the expensive booster or add more capacity to the cylinder, a costly system overhaul. 

4. Inefficiency During Peak Production

Consider a situation where your shop is running full tilt to meet a deadline. Your lasers are cutting thick plate and consuming nitrogen at max flow rates. While this is happening, the storage system is trying to refill the tanks. Since the generator is only sized for average demand, it cannot keep up with peak withdrawal. Eventually, the storage bank depletes, causing the pressure to drop below the minimum required for the laser and halting production. 

Inefficient storage systems can lead to costly downtime as you wait for the system to recover. While facilities often oversize the storage capacity to avoid this issue, that only negates any initial capital savings and increases their system footprint. 

The Advantages of On-Demand Nitrogen Generation  

With on-demand nitrogen generation, you can enjoy intelligent real-time production, lower energy costs, greater reliability, a safer operational environment, and true scalability. 

Intelligent, Real-Time Production

On-demand systems produce nitrogen only when your laser is cutting. When you stop the laser to load a part or change a nozzle, the generator automatically goes on standby. This eliminates waste, as you are not spending electricity to compress gas that sits in a tank. The idea of generating as you go mirrors the efficiency of the lasers themselves. Liberty Systems offers nitrogen generators that produce ultra-high purity nitrogen, up to 99.999%, exactly when your laser system demands it. 

Superior Mid-Pressure Design 

By operating at 450 psig, on-demand systems use pressure swing adsorption (PSA) technology with standard industrial compressors. These parts are durable and widely available. They are also far more affordable to maintain than high-pressure boosters.

The energy savings are substantial. Since you are only compressing the nitrogen to the pressure needed for cutting, you avoid the massive energy penalties of 4,500-psig storage. The result is lower electric bills each month and a smaller carbon footprint. 

True Scalability for Business Growth

On-demand systems are modular. If you add another laser, you can simply add another module to your existing nitrogen generation skid. You do not need to take out high-pressure piping or replace massive boosters. With this level of scalability, you can start with the capacity you need currently and then expand cost-effectively as your business grows. 

Design Your On-Demand Solution With Liberty Systems

On-demand nitrogen generation offers numerous advantages for laser cutting facilities, from lower operational costs to better scalability. To realize its full benefits, however, you need a reputable partner with a proven track record of delivering reliable, high-quality nitrogen generation systems. Liberty Systems designs on-demand nitrogen generation systems with superior laser cutting gas supply technology. As an ISO 9001-certified provider, we adhere to the highest standards of quality and consistency. 

With deep expertise in both laser cutting technology and industrial gas generation, we design reliable, purpose-built solutions for your operations. Our approach is consultative. We analyze your specific flow and pressure requirements to design a system that maximizes uptime and minimizes waste. We also provide comprehensive support. Our trained technicians will service your generator and train your team so you know how to use and maintain it yourself. 

Take control of your gas supply and your bottom line. Contact us today to discover the true value of on-demand nitrogen generation.