Load shifting means moving the energy use of flexible loads — chillers, compressed air and parts of production — out of the on-peak window (where the energy rate runs roughly three times off-peak under the PEA/MEA TOU tariff) to lower the demand charge, which is billed on your highest 15-minute kW in the cycle. The key point: you can start without a battery. Pre-cool (store cold) during off-peak then throttle chillers at on-peak, sequence your air compressors, and move non-urgent jobs out of the peak. Every kW you shave off the peak is demand charge saved every month. Once manual shifting works, the next steps are an EMS (to automate it) and a battery (to shave the peak deeper).
What load shifting is — and how it differs from peak shaving
Load shifting means rescheduling energy use from the expensive window (on-peak) to the cheap window (off-peak) — the work still gets done, just at a different time. It differs from peak shaving, which uses a battery to discharge in place of the grid during the peak. Load shifting is primarily about managing run schedules, so you can start it first without buying new hardware.
Load shifting ≠ using less
Load shifting does not reduce total kWh consumed (it can stay the same) — it reduces your cost per kWh by moving to the cheaper window, and lowers the peak kW that the demand charge is billed on. Cutting consumption outright (e.g. efficient motors) is a separate lever you can pull alongside.
Load shifting is the partner of peak shaving
The most cost-effective approach is to exhaust manual shifting first, then use a battery to shave the remaining peak — because every kW you shift for free is a kW the battery does not have to carry, so the battery you buy is smaller and pays back faster.
Why shifting load actually cuts the demand charge
The demand charge is billed on the highest power draw (kW) your plant pulls from the grid in any 15-minute interval of the cycle (typically weighted to on-peak). So when many machines start or run at full power simultaneously during on-peak, the peak spikes. Spreading and shifting load out of that moment lowers the peak kW directly.
On-peak rates run ~3× off-peak
Under the PEA/MEA TOU structure, the on-peak energy rate is far higher than off-peak (roughly 3× as a rule of thumb). Every kWh you move from on-peak to off-peak saves that price difference immediately — the second lever that comes alongside cutting the demand charge.
Avoided peak = money saved every month
The demand charge is a recurring monthly cost. Shaving even a few tens of kW off the peak lowers the bill month after month — unlike a one-off kWh reduction whose effect depends on that month's usage volume.
Illustrative, not a guarantee: Thai studies have found that cooling / cold-storage loads often have peak-shift potential in the region of 25-41% when pre-cooling and run windows are managed well. Actual figures depend on each plant's load profile and process — compute from your real bill.
5 loads you can really shift in a Thai factory — ranked by ease
Not every load is shiftable. The fastest levers are loads whose output you can store ahead (cold, compressed air). This table ranks them from easiest to hardest, with the move to make.
| Load | The move | Ease |
|---|---|---|
| Chillers / cold storage (pre-cool) | Store cold during off-peak (lower the setpoint), then throttle/cycle off some units during on-peak, letting temperature drift within an acceptable band | Easiest |
| Compressed air | Build tank pressure during off-peak, sequence compressors, cut secondary units at peak, and fix leaks first | Easy |
| Charging (EV / forklift / battery) | Schedule forklift/EV/backup-battery charging into off-peak or midday solar surplus, instead of plugging in during the on-peak evening | Easy |
| Production sequencing (batch) | Move non-urgent batch jobs, or stagger machine start-ups so they don't pull a simultaneous peak during on-peak | Medium |
| Pumping / fill jobs (tank-buffered) | Pump water/liquid up to storage tanks during off-peak then feed from the tank during on-peak — using the tank as a “liquid battery” | Medium |
Note: always start with chillers and compressed air — these two pay off fastest because their output can be pre-stored, and they usually make up a large chunk of a plant's peak.
The 4-step playbook — start cutting the demand charge this month
No capex budget required. Start from data you already have in your bill and meters, and follow these four steps in order.
1. Find when the peak happens and from what
Read the demand (kW) on your bill, and if you have interval/sub-meters, find which 15-minute window the peak lands in and which machines run together then. That is your first shifting target.
2. Shift the free wins first (pre-cool + sequence)
Pre-cool cold storage/chillers during off-peak, sequence compressors, and move charging and non-urgent batch jobs out of on-peak — all of this is done by scheduling, with nothing to buy.
3. Set a manual peak ceiling (demand limit)
Agree with the production team on a rule: total kW must not exceed this ceiling during on-peak. Use a meter alarm or a shift checklist, with a pre-rehearsed order of which loads to throttle.
4. Measure → repeat → then consider automation
Compare the demand (kW) on next month's bill; if it dropped, extend to other loads. When manual shifting starts to stumble or clash with production, that's the signal to invest in an EMS to automate it, and/or a battery to shave the remaining peak.
Worked logic, illustrative (not a guarantee)
We explain the way to think about it rather than giving a fixed baht figure, because the demand-charge rate (THB/kW) and load profile differ for every plant. Always plug in numbers from your own bill.
- Step 1 — demand-charge saving = (peak kW you shave) × (your bill's demand-charge rate in THB/kW) per month. Logical example: if you shave X kW off the peak and your bill rate is Y THB/kW, you save X×Y baht every month.
- Step 2 — energy-spread saving = (kWh you move from on-peak to off-peak) × (the on-peak − off-peak rate difference). Because on-peak runs roughly 3× off-peak, every shifted kWh saves that difference immediately.
- Step 3 — combine both levers: monthly saving ≈ (demand-charge saving) + (energy-spread saving). Because the demand charge recurs every month, the annual total is ×12 — but this is only the logic; compute from your real numbers.
Illustrative only: we guarantee no figures. Actual results depend on the share of flexible load, the tariff structure and each plant's production behavior. Use the calculators below with your real bill.
Manual → EMS → battery — invest in the most cost-effective order
Don't jump straight to buying a battery. The most cost-effective order is to exhaust the free actions first, then pay for what automates and deepens the result.
Stage 1 — manual shifting (0 capex)
Pre-cooling, sequencing, a checklist-based peak ceiling — start immediately and prove which loads truly shift without hurting production.
Stage 2 — EMS automates it
When manual work starts clashing with daily operations, an EMS watches total kW in real time and throttles/shifts loads automatically by rule — delivering more consistent results without relying on people.
Stage 2: factory energy management system (EMS/FEMS)Stage 3 — battery shaves the rest
For the peak you cannot shift (loads that genuinely must run at on-peak), use a battery to discharge in place of the grid at the peak. Because you already shifted the free part, the battery you buy is smaller and pays back faster.
Stage 3: peak shaving with solar + batteryPitfalls — shifting wrong can create a new peak
Load shifting pays off only when done systematically. Here are the common traps.
Creating a new peak when off-peak starts
If every machine starts at the instant off-peak begins, you can create a fresh peak. Stagger the start-ups instead of switching everything on together.
Shifting that hurts quality/production
Don't shift loads that affect product quality or safety (e.g. letting cold-storage temperature exceed the acceptable band). Always set safe limits first.
Forgetting demand is measured all month
The demand charge is usually billed on the single highest peak of the cycle — one slip can lift the whole month's bill. Control the peak consistently every day, not only when you remember.
CapSolar designs and installs end-to-end solar + storage + EMS for factories in Thailand. With 150+ projects, 80+ MWp installed and 100+ clients, we help you sequence the “shift manually first, then automate and add storage” path for maximum value.
Frequently Asked Questions
Want to cut your demand charge this month without big capex?
The CapSolar team helps you find shiftable loads and sequence the manual → EMS → battery path for maximum value at your plant.