Case Study: Ventilation-on-Demand to Cut a Mine's Power Bill

At a glance

The deployment in one view.

Operation

An underground mine where ventilation is among the largest electricity loads

Problem

Escalating tariffs and outages, while fans run flat-out around the clock — even in unoccupied areas

What we monitored

Airflow, gas (CO, CH₄, NO₂, O₂), differential pressure, fan status and power

Then

Ventilation-on-demand on auxiliary fans, tied to monitoring and occupancy

Safety

Fail-safe: defaults to full ventilation on any sensor fault, gas alarm or comms loss

The shift

From ventilating everywhere always to delivering air where and when it's needed

The challenge

For South African mines, escalating electricity tariffs and power outages are now front-line threats to competitiveness — and underground ventilation is often the single biggest electricity consumer on site. Yet the conventional approach is to run main and auxiliary fans flat-out, all the time, to stay safe — which means paying full power to ventilate headings with nobody in them. The mine wanted to cut that cost without ever compromising the air at the face.

The physics that makes it worth it: fan power rises roughly with the cube of airflow, so a modest reduction in airflow where it isn't needed yields a disproportionately large energy saving — but only if you can prove the air is safe before you reduce it.

Our approach

Monitor for assurance first. Airflow and gas at the working places and key splits, plus the main fans — so every area's ventilation can be proven and any shortfall alarmed instantly (see mine ventilation monitoring).
Find the waste. The data shows where the mine is over-ventilating relative to occupancy — the candidates for demand-based control.
Introduce ventilation-on-demand. Auxiliary airflow follows occupancy — reduced when an area is empty, ramped up when people or diesel machines move in — informed by monitoring and person location.
Keep safety primary. Interlocks always default to more air, never less: any sensor fault, gas alarm or comms loss reverts the area to full ventilation.
Prove the saving. Fan energy measured before and after, alongside occupational hygiene on one platform — so safety and savings are visible together.

What changed

Safety first; the energy saving follows.

Air proven safe everywhere

Continuous airflow and gas monitoring confirms every working place meets its requirement — and alarms a shortfall instantly.

A major power bill, trimmed

Matching auxiliary ventilation to occupancy cuts fan energy disproportionately, without touching the air at the face.

Fail-safe by design

On any doubt — sensor fault, gas alarm, lost comms — the system reverts to full ventilation. Savings never come before safety.

Why it fits South Africa

When power is the cost that's hurting most.

With tariffs climbing and outages eroding productivity, energy is one of the few big costs a mine can actually attack — and ventilation is the largest lever. Ventilation-on-demand turns a fixed, flat-out power draw into one that tracks real occupancy, and because it's built on monitoring that proves safety first (and fails safe), it cuts cost without trading away the air miners depend on. Edge buffering keeps the safety record continuous through load shedding.

See the mining optimisation solution and the ventilation monitoring guide.

This case study illustrates addanode's approach through a representative scenario; client details and figures are omitted by policy. Ventilation design and any control strategy must be set and signed off by the ventilation engineer and aligned to the Mine Health and Safety Act.

Ventilation-on-demand to cut a mine's power bill

The deployment in one view.

The challenge

Our approach

Safety first; the energy saving follows.

Air proven safe everywhere

A major power bill, trimmed

Fail-safe by design

When power is the cost that's hurting most.

Ventilating flat-out, all the time?

Ventilation-on-demand to cut a mine's power bill

The deployment in one view.

The challenge

Our approach

Safety first; the energy saving follows.

Air proven safe everywhere

A major power bill, trimmed

Fail-safe by design

When power is the cost that's hurting most.

Ventilating flat-out, all the time?

Related reading

Mine ventilation monitoring & VOD

Occupational hygiene monitoring

Mining Optimisation