Appearance
The coolant pump on a BTA machine draws more power than the spindle — 40–60% of total energy. Over 4,000 hours at $0.12/kWh, the pump alone costs $25,000–50,000. VFD pumps and high-efficiency motors save 20–35% — $7,000–22,000 per year. Energy is the third-largest operating cost and the easiest to manage.
Power Consumption Breakdown
| Component | Typical Power | % of Total | Annual Cost* |
|---|---|---|---|
| Coolant pump (high-pressure) | 15–75 kW | 40–60% | $15,000–50,000 |
| Spindle drive | 10–50 kW | 20–35% | $8,000–25,000 |
| Hydraulics | 5–15 kW | 10–15% | $4,000–12,000 |
| Filtration and chip handling | 3–10 kW | 5–10% | $2,500–8,000 |
| CNC and controls | 2–5 kW | 3–5% | $1,500–4,000 |
*Based on 4,000 hours/year at $0.12/kWh.
Cost per Hole Benchmarks
| Material | Hole Size | Energy per Hole | Energy Cost | Total Operating Cost per Hole |
|---|---|---|---|---|
| 4140 steel | Ø25 × 500 mm | 0.8–1.2 kWh | $0.10–0.14 | $6–12 |
| 4140 steel | Ø40 × 800 mm | 2.5–3.5 kWh | $0.30–0.42 | $12–25 |
| Inconel 718 | Ø12 × 400 mm | 1.5–2.5 kWh | $0.18–0.30 | $20–50 |
| Aluminium 7075 | Ø15 × 300 mm | 0.3–0.5 kWh | $0.04–0.06 | $3–6 |
Energy Reduction Strategies
| Strategy | Saving Potential | Implementation Cost | Payback |
|---|---|---|---|
| VFD on coolant pump | 20–35% pump energy | $3,000–10,000 | 6–18 months |
| High-efficiency motors (IE4) | 5–10% motor energy | Premium 15–25% | 12–24 months |
| Coolant temperature optimisation | 10–15% chiller energy | $0 (setpoint change) | Immediate |
| Standby mode programming | 5–10% total energy | $2,000–5,000 | 6–12 months |
| LED lighting upgrade | Minimal | $500–2,000 | 12–18 months |
FAQ
How much does it cost to run a deep hole drilling machine per hour?
$15–35 per hour all-in (energy + consumables + maintenance allocation), excluding labour. Energy alone is $6–15 per hour.
Does running at higher feed rates reduce energy cost per hole?
Counterintuitively, yes — for the same spindle speed, higher feed reduces cutting time, so total energy consumption per hole decreases even though instantaneous power is higher.
Is it cheaper to run the coolant pump at reduced pressure when not cutting?
Yes. Reducing coolant pump speed to 50% during idle periods saves approximately 75% of pump energy (pump power follows the cube of speed).
How do energy costs compare between gun drilling and BTA?
BTA drilling consumes 2–4× more energy per hole due to higher coolant flow requirements. However, BTA removes material faster, so energy per unit volume is comparable.
Should I track energy cost per hole?
Yes. Energy cost is stable and predictable, making it an excellent baseline for detecting process changes. A sudden increase in energy per hole often indicates tool wear or coolant system problems before other symptoms appear.
Energy costs depend on local utility rates, machine utilisation, and operating parameters. Calculate your specific costs using actual power measurements where possible. This article reflects typical US industrial rates as of 2026.