Replacing a compressor means choosing a machine for 15 years or more. Over that period, electricity is by far the largest cost, well ahead of purchase price and maintenance. The choice between fixed and variable speed therefore directly affects your profitability.
The fixed-speed compressor
How it works
The motor always runs at the same speed. When maximum pressure is reached, the compressor goes into idle: it keeps running without producing air, still drawing 20 to 30% of its rated power, then stops after a delay.
When to choose it
- Steady demand close to the machine’s capacity
- Base-load duty in a multi-compressor station
- Limited capital budget
The variable-speed compressor
How it works
A frequency converter constantly adapts motor speed to air demand. Pressure stays stable within ±0.1 bar and idle running almost disappears.
When to choose it
- Demand that varies widely over the day or week
- Processes sensitive to pressure stability
- Goal of cutting the energy bill
The best solution: combine both
In most plants, the best configuration pairs one or more fixed-speed compressors for base load with a variable-speed unit to follow peaks. A central control such as BOGE airtelligence provis 3 picks the most economical combination at every moment.
Measure before deciding
The right choice is not made from a catalogue. Deutsche TechnicAir installs a consumption logger on your station for one to two weeks. The resulting profile lets us size the new installation precisely and quantify the expected saving before any investment.
Frequently asked questions
Does a variable-speed compressor cost more?
Yes, to buy. But when demand varies, the energy saving often pays back the difference in two to three years.
Can an existing station be upgraded?
Yes. A variable-speed compressor and central control can be added alongside your current machines.
A question about your installation?
Our engineers assess your needs and propose the right BOGE solution.