1. Philippine primary energy in: ~2,400 PJ/year. Useful energy out: ~700 PJ. Rejected as waste heat: ~1,700 PJ.
2. For every 1 kWh of useful work a Filipino receives, the country burns 2.4 kWh of fuel to deliver it.
3. This is not bad operating practice. It is the design of the system we inherited.
4. Heat pumps don't combust anything — they reverse the inheritance at the customer level, one boiler at a time.
The national energy ledger, drawn to scale
That box on the right marked "rejected energy" is more than twice the size of the box marked "useful." It is the waste that runs your country's electricity bill, drives the foreign-exchange demand for imported coal and diesel, and contributes 73% of the Philippines' greenhouse gas emissions — all to deliver the same amount of useful work that an efficient electrified system would deliver from a fraction of the primary energy.
Why the waste is so large
Every combustion engine ever built obeys the same physical law. The Carnot limit (Sadi Carnot, 1824) caps the maximum theoretical efficiency at which heat can be converted to work. Real-world losses pull the actual delivered efficiency below the theoretical ceiling:
- Petrol car engine — 25% efficient. 75% of the petrol you buy goes up the exhaust pipe as heat.
- Diesel generator — 40% efficient. 60% out the exhaust.
- Coal-fired power station — 33% efficient. Two thirds of the coal goes up the cooling tower as warm water.
- Best combined-cycle gas turbine — 60% efficient. The state of the art, after 200 years of refinement.
The ceiling has not moved. A 1980 diesel engine and a 2026 diesel engine are both 40% efficient. The Carnot limit is set by physics — by the temperature difference between the combustion chamber and the cold reservoir. No amount of engineering improvement at the margins changes the fundamental ratio.
Now apply that ceiling across every fossil-fuel asset in the Philippine economy — coal-fired power stations delivering electricity, diesel generators backing up the grid, diesel and LPG boilers in hotels, hospitals, food plants, bakeries, laundries — and the cumulative rejection adds up to 1,700 petajoules a year.
The Sankey is not a flaw in operation. It is the design of the system we inherited — built in an era when the only way to release thermal energy was to set something on fire.
The same picture exists everywhere — the Lawrence Livermore lab publishes one annually
This pattern is not unique to the Philippines. The Lawrence Livermore National Laboratory in the United States publishes a national energy Sankey diagram every year, and the US version looks structurally identical: roughly 65% rejected energy, 35% useful. The same is true for the UK, Germany, Australia, Japan, and effectively every economy built around combustion-based generation.
The waste is the inheritance of a global energy architecture designed in the 19th and 20th centuries. The good news is that the lever to dismantle it — the heat pump — has been industrially available since the 1920s and commercially competitive since the 1970s. The reason it hasn't taken hold globally is not technical. It is the same reason most retrofit decisions stall: capex bias against operational savings, vendor incentives to sell the box they already have, and energy prices low enough that the inefficiency was tolerable.
The Strait of Hormuz closure has changed that equation. With diesel above ₱75/L industrial delivered and Meralco at ₱14/kWh blended, the inefficiency is no longer tolerable. The payback math that took 30 months in 2022 now takes 12 — and under sustained crisis pricing, 8.
How the waste comes down, one boiler at a time
The 1,700 PJ of national rejected energy is the sum of millions of individual combustion decisions — every diesel boiler, every LPG kitchen, every electric resistance hot water tank, every chiller dumping condenser heat to the alleyway when the proofer next door is buying the same heat back from the grid. Each one of those decisions is reversible at the customer level, on a single capex cycle, with payback in months.
A single Karnot heat pump replacing a diesel boiler on a 100 kW thermal duty shifts approximately 720,000 kWh per year from the rejected-energy column to the useful-energy column. Multiply across a thousand sites and the national Sankey starts to bend.
The transition does not happen from a government plan. It happens from the businesses in the productive sector — the hotels, hospitals, food manufacturers, bakeries, cold-chain operators, and breweries — each making one local capex decision at a time, on the same logic that decided every previous capex decision: the payback math.
Want to see your share of the 1,700 PJ?
Book a free site survey. We model your facility's primary-energy-in vs useful-energy-out, identify the largest rejection points, and quote the heat pump + solar package that closes the loop — no commitment.
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