Heat from the cooler.Power for the proofer.
Commercial bakeries do two opposing thermal jobs at the same time — heating the proofer to 44 °C and cooling the bread back to 22 °C. Today most plants pay for both jobs twice: a chiller dumps usable heat to atmosphere, an electric resistance heater buys it back from the grid. The Karnot SHC architecture — iHEAT R290 reversible + twin iSTOR PCM tanks + dual AHUs + iVOLT solar — runs both loads from one heat-pump loop. Combined COP 6–8. ~70% off the thermal energy bill.
The bakery pays for the same kilowatt twice.
Both proofing and cooling are narrow-window biochemical processes. The dough is alive in the proofer; the crumb is setting in the cooler. A 5 °F deviation in either window cascades into product loss the operator can't recover — and the energy bill compounds because every BTU is paid for twice.
Electric resistance proofing — COP 1.0
Most Philippine commercial bakeries heat the proof box with electric resistance elements — 1 kWh of grid power for 1 kWh of heat. At Meralco GP April 2026 tariff (~₱14/kWh blended), a 50 kW proofer running 16 hours/day costs ~₱11,200 per day on heat alone. That is the cheapest thermal kilowatt-hour the plant could possibly buy — and it is roughly four times what the same heat costs from a heat pump.
Cooling hall — dumping useful heat
Hot bread coming off the oven releases 2–3% of its mass as latent moisture while cooling. The cooling hall needs continuous dehumidification at 20–25 °C / 60–70% RH. Today an air-cooled chiller hauls all of that energy to atmosphere via the condenser — and the proofer next door buys equivalent grid power to make new heat. The same kilowatt, paid for twice, every hour the plant runs.
Product loss — protease, shaling, mould
Proof box too hot: yeast enzyme activity doubles every 10 °C, protease blowout collapses the cell structure. Proof box too dry (RH below 70%): a rigid skin forms (shaling) that physically inhibits expansion — dense, undersized buns rejected at QC. Cooling hall too warm: bread sliced and bagged above 43 °C traps internal vapour, water activity climbs >0.80, and Rhizopus or Penicillium colonies germinate within 48–96 hours inside the bag.
F-gas phasedown clock on R404A and R410A
Bakery chillers and cold rooms running on R404A (GWP 3,922) or R410A (GWP 2,088) are on a phasedown clock under DENR DAO 2021-31 (PH Kigali codification) and ahead of EU F-gas (95% reduction by 2030). Any new chiller specified today on a high-GWP synthetic is a stranded asset by 2032. R290 (GWP 3) and water (GWP 0) have no phasedown clock.
One heat pump. Two jobs. Done at the same time.
Karnot Simultaneous Heating & Cooling (SHC). The iHEAT R290 reversible heat pump extracts heat from the cooling-hall AHU and delivers it to the proofing AHU in the same cycle. The two iSTOR PCM tanks buffer the imbalance between cooling and proofing demand minute-by-minute — both halls see continuous, stable conditions. The bread cools the dough. The dough heats itself.
iHEAT R290 reversible
SHC engine. Extracts heat at the cooling AHU, upgrades it through the compressor, delivers it straight to the proofing AHU. Combined COP 6–8. R290 natural refrigerant, GWP 3, no phasedown clock.
iSTOR PCM × 2
Two phase-change thermal batteries — hot tank @ 44 °C, cold tank @ 22 °C. Patented PCM, natural fluids sourced in the Philippines. Buffer imbalance between the two AHUs so neither hall sees an interruption.
Twin Karnot AHUs
Proofing AHU delivers 40–46 °C / 80–90% RH on a humidistat. Cooling AHU holds 20–25 °C / 60–70% RH with HEPA filtration and positive pressure (CIBSE Guide B2 — flour-dust and spore exclusion).
iVOLT solar + Li-ION
Zero-export rooftop PV + Karnot inverter + LiFePO4 battery. Sized to carry the SHC loop through daylight hours. Pushes bakery thermal cost from ~₱4,480/day (grid-SHC) to ~₱1,500/day (grid + solar).
100 kW thermal. ~80% off the daily energy bill.
Modelled on a typical mid-size commercial bakery running a 100 kW combined thermal load (proofing box + DHW + cooling-hall reheat) for 16 hours/day, 6 days/week. Tariff: ₱14/kWh blended Meralco GP April 2026 plus combined demand charges of ~₱700/kW. Existing electric-resistance + chiller plant: ~₱22,400/day. Karnot SHC at combined COP 5.0: ~₱4,480/day — a 80% reduction. With a 15 kWp iVOLT solar bolt-on: ~₱1,500/day — a 93% reduction. Annual saving on the heating side alone: ~₱6.5M. Demand-charge saving: ~₱56K/month. Per-facility payback: 18–36 months on industry F&B benchmark. Real numbers from a free site audit.
Capital purchase. 18–36 month per-facility payback.
Karnot equipment is sold outright with a 3-year warranty on the heat-pump core. Per-facility payback figures are from industry F&B heat-pump benchmarks at Meralco GP April 2026 tariff. Energy-efficiency capex may qualify for BOI incentives under RA 11285 — Karnot supports the registration paperwork; the final package is confirmed by BOI on a case-by-case basis.
From day one, the bill drops.
Single contractor. Phased install.
Karnot delivers the whole stack — survey, design, BOI registration, install, commissioning, M&V — under one contract per facility. Production runs through commissioning — we install on the next planned shutdown, no lost batches.
- Mo 1: Site survey, ASHRAE Ch. 41 thermal-load model, BOI paperwork
- Mo 2–3: Mechanical design, twin-AHU package, hydronic loop layout, long-lead procurement
- Mo 4–5: Install iHEAT outdoor unit + iSTOR tanks + AHUs · commissioning · witness testing
- Mo 6: iVOLT solar (where roof permits) · IPMVP M&V baseline · handover
Download the Bakery Application Brief
The full 16-slide deck — ready to share with your production manager, your CFO or your board.
Engineering Tools for Bakery Projects
Free calculators to size your bakery SHC system.
Frequently Asked Questions
Why do bakeries pay twice for the same heat?
A commercial bakery runs two opposing thermal loads simultaneously — the proofing box needs 40–46 °C / 80–90% RH, and the cooling hall needs 20–25 °C / 60–70% RH to cool bread before slicing. Conventional plant runs an electric resistance heater for proofing AND a chiller for cooling. The chiller dumps usable heat to atmosphere; the proofer buys the same heat back from grid electricity. The bakery pays for the same kilowatt twice.
What is the Karnot bakery architecture?
Simultaneous Heating and Cooling (SHC). One iHEAT R290 reversible heat pump moves heat from the cooling hall AHU directly to the proofing AHU. Two iSTOR thermal batteries (hot tank at 44 °C, cold tank at 22 °C, patented PCM) buffer the imbalance between the two loads. Combined COP 6–8 — one unit of compressor input delivers ~3.5 kW of cooling AND ~4.5 kW of heating simultaneously.
What payback can a Philippine bakery expect?
18–36 months on a per-facility basis, vs an electric resistance + air-cooled chiller baseline at Meralco GP April 2026 tariff (~₱14/kWh blended). A worked 100 kW thermal load case (typical mid-size commercial bakery, 16h/day, 6 days/week) gives ~80% reduction in daily thermal-energy cost — from ~₱22,400/day on electric resistance to ~₱4,480/day with Karnot SHC. With an iVOLT solar bolt-on, the same load drops further to ~₱1,500/day.
What compliance standards govern bakery climate plant?
ASHRAE Refrigeration Handbook Ch. 41 (Bakery Products) sizes the evaporator for latent moisture from cooling bread. Ch. 23 (Refrigerated Facility Design) governs vapour-barrier integrity for the Philippine wet season. EN 378 / ASHRAE 15 / IEC 60335-2-89 govern R290 charge limits — Karnot uses indirect monoblock architecture so the entire R290 circuit lives outdoors and only safe water/glycol enters the bakery. CIBSE Guide B2 governs HEPA filtration and positive pressurisation against flour dust and spore ingress. IPMVP Option B provides bankable M&V on the energy saving.
Why two iSTOR tanks instead of one?
The bakery needs two iSTOR tanks because the cooling demand and the proofing demand are rarely perfectly balanced minute-by-minute. The hot tank at 44 °C carries excess proofing heat; the cold tank at 22 °C carries excess cooling capacity. When demand on either side spikes, the corresponding iSTOR tank discharges to the AHU — no warehouse interruption, no heat-pump short-cycling, continuous stable conditions on both halls.
What happens during a power outage?
The dual iSTOR tanks provide thermal inertia — the bakery stays at spec for hours even during grid events. When iVOLT solar + Li-ION battery is installed, the SHC loop can run grid-zero through daylight. Long brownouts can be bridged with the customer's existing standby generator on the iSAVE feeder; the heat pump restarts automatically and the iSTOR tanks bridge the transition.
Ready to stop paying for the same kilowatt twice?
Book a free site survey. Our engineers will model your bakery's combined thermal load using the ASHRAE Refrigeration Handbook Ch. 41 method, size the iHEAT + dual iSTOR + twin AHU + iVOLT package, and show you the exact payback at today's Meralco tariff.