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Use case

Peak shaving

A plastics plant runs steady most of the day — until the extruders and presses fire together and demand jumps by a third for twenty minutes. TNB bills the whole month on that twenty minutes.

Plastics & extrusionMetal & machiningRubber & moulding
The situation

Representative site · Plastics extrusion, Klang Valley

Picture a mid-size injection-moulding and extrusion plant in the Klang Valley. For most of the day it draws a steady ~480 kW. But when a shift starts and the heaters, hydraulics and chillers come on together, demand briefly spikes to around 750 kW. That coincident surge lasts minutes — yet it sets the Maximum Demand for the entire billing month.

What it costs today

One twenty-minute surge, billed all month

Because TNB sets Maximum Demand from the single highest 30-minute interval, that 750 kW peak is charged in full — every kilowatt, every month — even though the plant only touches it briefly. At RM 97.06/kW, that one surge carries a heavy fixed line on every bill.

RM 72,795 / mo

750 kW × RM 97.06/kW — the demand charge set by a few minutes of surge. Representative, based on the TNB RP4 tariff.

How UniBess solves it

We don’t change how the plant runs. The battery simply absorbs the surge so the meter never records it.

1

Learn the load

We study a year of half-hourly data to find a demand ceiling the battery can defend — here, around 620 kW.

2

Cap every surge

When the shift-start surge pushes toward the ceiling, the BESS discharges within milliseconds to cover the difference. The meter sees 620 kW, not 750.

3

Refill off-peak

Overnight the battery recharges at the off-peak rate, ready for the next day. No operator involvement.

The outcome

130 kW shaved, every billing cycle

Same production, same schedule — only the metered peak changes. The demand charge falls by the shaved kilowatts, and because it’s a fixed rate, the saving repeats every single month.

Without a battery
  • Metered demand: 750 kW
  • Demand charge: RM 72,795 / mo
  • Set by a few minutes of surge
With UniBess
  • Metered demand: ~620 kW
  • Demand charge: ~RM 60,177 / mo
  • Surge absorbed by the battery
≈ RM 12,600 saved / month ≈ RM 151,000 a year, captured every cycle. Representative figures based on the TNB RP4 tariff — we model your real data before quoting.

Is this your site?

Peak shaving pays hardest where demand is spiky, not flat. You’ll likely benefit if:

  • Your metered peak sits well above your average daytime load.
  • Heavy equipment starts together — presses, extruders, compressors, large motors.
  • Maximum Demand is a big, stubborn line on your TNB bill.
  • Your peaks are short — minutes, not hours.

Where we're honest

Peak shaving needs honest data, not optimism. If your interval history doesn’t show a clean, defendable ceiling, we’ll tell you — an undersized battery that misses one surge still pays the higher demand charge for the whole month.