This cold chain heat recovery case study looks at a refrigerated distribution center that captures condenser reject heat to warm the dispatch area and preheat sanitation water, instead of dumping it outdoors. The Opportunity Every kW of cooling at the evaporator becomes roughly 1.2 to 1.4 kW of heat at the condenser. In cold chain […]
ASHRAE 90.1 Heat Recovery Requirements
ASHRAE Standard 90.1 is the reference energy standard for commercial buildings in the United States, and its exhaust-air energy recovery rule is the single most common code trigger for specifying a heat recovery ventilator. This article summarizes the ASHRAE 90.1-2022 requirements that apply to designers specifying air-to-air recovery. When Recovery Is Mandatory (Section 6.5.6.1) A […]
Desiccant Dehumidification Heat Recovery
Desiccant dehumidification heat recovery combines moisture removal with energy recycling. A desiccant material (solid wheel or liquid solution) absorbs water vapor from process air; the now-concentrated desiccant is regenerated using low-grade heat, and that regeneration stream’s energy is recovered rather than wasted. Why Pair Desiccation with Recovery Conventional cooling-only dehumidification overcools then reheats the air, […]
Data Center Heat Recovery with Rotary Wheels
Server rooms reject enormous, constant heat. An energy recovery wheel between the exhaust and make-up air streams cuts the cooling load and can redirect that warmth to heat adjacent office space. For data centers chasing PUE, recovery on the ventilation air is a straightforward win. The load you can recover IT power is almost entirely […]
Fume Hood Exhaust Recovery: Wheels vs Plates
Laboratories exhaust enormous volumes of conditioned air through fume hoods, often around the clock. Recovering the energy in that exhaust before it leaves the building is one of the fastest-payback upgrades in laboratory HVAC — and the choice between a rotary wheel and a plate exchanger decides how much you actually save. Why labs bleed […]
Commercial Kitchen Heat Recovery from Exhaust
Commercial Kitchen Heat Recovery: Capturing Energy from Exhaust with Air-to-Air Heat Exchangers Walk into any busy restaurant kitchen at dinner service and you will feel it: a wall of hot, greasy exhaust air being thrown out through the hood, while at the same time the make-up air unit is burning energy to condition cold outside […]
Heat Pump Waste Heat Recovery: Lifting Low-Grade Heat
The low-grade problem Much recoverable heat is low-grade – 25-60C drain water, vent air, or process streams. Too cool to use directly, but too warm to waste. A heat pump lifts it to a useful temperature using a little electrical work. How it pairs with air-to-air recovery Start with passive air-to-air or air-to-water recovery to […]
District Energy Station Heat Recovery: Sharing Heat Across Buildings
One plant, many buildings A district energy station produces heating and/or cooling centrally and distributes it through a network to multiple buildings. Recovery is built in at two levels: the central plant reuses its own waste heat, and buildings return low-grade heat to the network. CHP at the core Many stations run combined heat and […]
Cold Chain Logistics Heat Recovery: From Cold Store to Condenser
A cold chain is a heat chain Cold stores, freezers, and refrigerated warehouses move heat out continuously. That rejected heat is a free resource – if you capture it. Cold-chain recovery turns a pure energy cost into a partial energy gain. Where the heat is Condenser reject – the biggest, hottest stream (30-50C). Route it […]
Commercial Building Heat Recovery: Offices, Hotels, Mixed-Use
The everyday opportunity Offices, hotels, and mixed-use buildings run ventilation around the clock with high fresh-air rates. Recovering that exhaust energy is the single biggest HVAC saving for most commercial stock. Technology mix Offices – balanced AHUs favor plate or rotary recovery; see AHU recovery. Hotels – guest-room ventilation plus laundry and pool loads; pair […]