Boiler Energy Saving: How Automation Cuts Coal and Power Costs

For textile processors, dyeing houses, food plants and chemical units, the boiler or thermic fluid heater (thermopack) is often the largest single energy cost. Yet many still run with manually set dampers, fixed-speed fans and operators adjusting fuel feed by eye. Modern boiler energy saving automation tackles these losses directly and usually pays for itself quickly.

Where boilers waste energy

• Excess air: too much combustion air carries heat out of the stack. Too little causes unburnt fuel. Manual control cannot keep the balance as load and fuel quality change.
• Fixed-speed fans with dampers: ID and FD fans run at full speed while dampers throttle the airflow, wasting electricity.
• Unstable pressure or temperature: operators run higher setpoints "to be safe", which burns more fuel.
• Poor fuel feed control: irregular coal or biomass feeding causes swings in combustion.
• Feed water pump running at full speed with a control valve throttling flow.

How automation fixes it

1. Automatic combustion control

A controller adjusts fuel feed and combustion air together based on steam pressure (or thermic fluid temperature), maintaining the right air-to-fuel ratio across the load range. Where an oxygen analyser is fitted, O2 trim fine-tunes the air to minimise excess air.

2. VFDs on ID and FD fans

Fan power follows the affinity laws: power is proportional to the cube of speed. Running a fan at 80% speed needs only about 51% of full-speed power. Replacing damper control with VFD speed control is one of the most reliable electricity savings in any plant.

3. VFD on the feed water pump

Level control by pump speed instead of a throttling valve saves power and gives smoother drum level.

4. Steady pressure and temperature

PID control holds pressure or temperature tightly, so setpoints can be lowered to what the process truly needs.

5. Monitoring and alarms

Trends of pressure, temperature, fan speed and fuel feed on an HMI help supervisors spot problems early, and alarm logs show exactly what happened before a trip.

Our GOC35-based boiler solution

AB Automation's boiler energy-saving automation uses the Mitsubishi Electric GOC35, an HMI with built-in control based on GOT2000 technology, together with FR-series VFDs on the fans. On steam boilers and thermopacks it is designed to:

• Save up to 20% of coal consumption
• Reduce electricity use by around 5%
• Give smart, automatic control with clear operator screens
• Support more eco-friendly operation with steadier combustion

Actual savings depend on the boiler's present condition, fuel and load pattern, which is why we start with a site study.

Is your boiler a good candidate?

• Dampers are set by hand and rarely changed.
• ID/FD fans run at fixed speed.
• Steam pressure or thermic fluid temperature swings noticeably.
• Fuel consumption per tonne of product has crept up.
• Black smoke or high stack temperature is common.

If two or more apply, there is very likely a worthwhile saving.

Start with a site study

We visit your boiler house, record current operation and fuel use, and estimate the savings before you commit. Book a boiler study or call +91 90331 37026. For other energy-saving measures, see our guide to APFC panels and power factor correction.