The contamination barrier Cleanrooms demand exceptionally high air-change rates – often 20 to 60 air changes per hour – to maintain ISO particle classes. That airflow represents a massive energy stream leaving the facility fully conditioned. Recovering it is essential, but cleanrooms add a hard constraint: supply and exhaust air must never mix. Because cross-contamination […]
Airport HVAC & Energy Recovery: Cutting Terminal Energy Use
Why terminals are energy hotspots Airports are among the most energy-intensive buildings in the commercial sector. Vast terminals run 24/7 with high fresh-air requirements, large glass facades, and constantly moving passenger loads. Heating and cooling the ventilation air alone can account for 40-60% of a terminal’s HVAC energy. Air-to-air heat recovery is the single highest-return […]
California Title 24 Heat Recovery
California Title 24, Part 6 (the Building Energy Efficiency Standards) is the most aggressive state energy code in the U.S., and its 2022 edition — effective 1 January 2023, with a July 2024 Supplement — puts heat recovery at the center of both nonresidential and multifamily compliance. This article distills the recovery provisions that trigger […]
Supermarket Heat Recovery: Refrigeration + Ventilation
Two loads, one building Supermarkets and big-box retail bleed energy in two ways: refrigeration rejects heat constantly, while fresh-air ventilation (bakery, deli, entrances) demands conditioning. Heat recovery bridges them. Ventilation recovery Exhaust from the sales floor is warm and can pre-heat incoming make-up air in winter via a rotary wheel or plate exchanger. In cooling […]
Wastewater Source Heat Recovery: Reusing Drain-Water Energy
The hidden reservoir Showers, wash-down, and process drains leave buildings at 25-40C – warm enough to be a valuable heat source. Wastewater (drain-water) heat recovery captures it before it disappears down the sewer. How it works Drain-water heat exchangers wrap a coil around or sit inside the greywater stream, pre-warming incoming cold water. Heat pumps […]
Waste-Heat Recovery Case Study: Stack & Exhaust
The opportunity A metal-finishing plant exhausted 18,000 m3/h of 160C air from curing ovens to atmosphere – pure lost energy. The brief was to recover it for winter make-up air heating and preheat a process water loop. The solution A high-temperature plate air-to-air exchanger (stainless, rated to 200C+) transferred exhaust heat to incoming fresh air. […]
AHU Heat Recovery Selection Calculation: A Step-by-Step Method
Step 1 – Known airflow Start with the supply/exhaust airflow Q (m3/h). For balanced AHUs, Q_supply approx Q_exhaust. Step 2 – Temperature difference Find the outdoor design temperature T_out and the exhaust (room return) temperature T_exp. The available temperature lift is DeltaT = T_exp – T_out. Step 3 – Effectiveness Choose an effectiveness epsilon (typical […]
Food Processing Heat Recovery: Capturing Process and Exhaust Heat
A heat-rich sector Food plants bake, cook, pasteurize, and chill around the clock. Both the process air and the building exhaust carry large amounts of recoverable energy – often with moisture, grease, or particulates that demand a cleanable, robust exchanger. Technology fit Enthalpic plate or rotary wheels recover both heat and moisture from humid exhaust […]
CHP Case Study: Cogeneration in a Real-World Facility
The site A 12,000 m2 district with a hospital wing, pool, and offices had a steady year-round heat demand and paid high grid electricity prices. A 500 kWe natural-gas CHP engine was installed to supply base-load power and capture jacket plus exhaust heat for space heating and domestic hot water. What it recovered Electrical output: […]
Hospital Heat Recovery Without Losing Air Quality
Why hospitals recover heat Hospitals run 24/7 with very high fresh-air rates – operating theatres, isolation rooms, and wards all demand conditioned outdoor air. Ventilation can be 30-50% of a hospital’s energy bill. Air-to-air recovery cuts that load sharply, but infection control sets a hard rule: supply and exhaust must never mix. The safe choice: […]