What efficiency can I expect?

Plate (counter-flow) exchangers: 60–75% sensible. Rotary (enthalpy) wheels: 70–85% including moisture. Cross-flow plates are typically 50–65%.

Which type should I choose?

Use plate types where air streams must not mix (pharma, food, labs). Use rotary wheels where humidity recovery matters. Avoid rotary wheels in explosive or highly contaminated exhausts — plate or heat-pipe instead.

Is the payback realistic?

For continuous operation (6,000+ h/yr) with a >15°C difference, payback is commonly 1–3 years. The calculator gives a first-order estimate; a detailed audit refines it.

Does this include fan power?

No — the estimate is gross recovered energy. Real net savings should subtract the extra fan energy from added pressure drop (usually 5–15% of recovered energy).

ZIBO QIYU · Heat Recovery Tools

Air-to-Air Heat Exchanger Energy Savings Calculator

Estimate how much energy, money and CO₂ you can save each year by recovering waste heat from exhaust air. Free, no sign-up.

Airflow rate

m³/h (total supply or exhaust air)

Temperature difference (exhaust − supply)

°C across the heat exchanger

Heat exchanger efficiency

% (typical plate: 60–75%, rotary: 70–85%)

Operating hours / year

h/yr (24×330 ≈ 7920)

Electricity price

$ / kWh

Equipment cost (optional)

$ for simple payback

Recovered heat power

0 kW

Annual energy recovered

0 MWh/yr

Annual cost saving

$0 /yr

CO₂ reduction

0 t/yr

Assumptions: air density 1.2 kg/m³, specific heat 1.005 kJ/kg·K, grid emission factor 0.55 kg CO₂/kWh. Results are indicative — contact our engineers for a project-specific assessment.

How the calculation works

An air-to-air heat exchanger transfers thermal energy between two air streams without mixing them. In winter it pre-heats incoming fresh air using warm exhaust; in summer (with enthalpy wheels) it can pre-cool supply air. The recoverable power is:

Q = airflow × 1.2 × 1.005 × ΔT × efficiency (kW)

Multiplying by annual operating hours gives the energy recovered, which is then valued at your electricity price and converted to avoided CO₂ emissions.

Why it matters for your facility

HVAC & ventilation: recover 60–85% of exhaust energy on make-up air.
Industrial drying: pre-heat process air using dryer exhaust — often the fastest payback.
Mining & tunnels: temper ventilation air to cut heating loads in cold climates.
Data centers: pair with indirect evaporative cooling to trim PUE.
Pharmaceutical & clean rooms: recover heat without recirculating contaminated air (plate type, no cross-contamination).

Frequently asked questions

What efficiency can I expect?: Plate (counter-flow) exchangers: 60–75% sensible. Rotary (enthalpy) wheels: 70–85% including moisture. Cross-flow plates are typically 50–65%.
Which type should I choose?: Use plate types where air streams must not mix (pharma, food, labs). Use rotary wheels where humidity recovery matters. Avoid rotary wheels in explosive or highly contaminated exhausts — plate or heat-pipe instead.
Is the payback realistic?: For continuous operation (6,000+ h/yr) with a >15°C difference, payback is commonly 1–3 years. The calculator gives a first-order estimate; a detailed audit refines it.
Does this include fan power?: No — the estimate is gross recovered energy. Real net savings should subtract the extra fan energy from added pressure drop (usually 5–15% of recovered energy).

This tool is for preliminary estimation only and does not constitute engineering advice. Zibo Qiyu designs plate, rotary and cross-flow air-to-air heat exchangers for industrial heat recovery — request a quote.