Energy Saving Kitchen Ventilation COMMERCIAL KITCHEN VENTILATION
Common misconceptions of kitchen ventilation. A ventilation system is usually at the bottom of priorities as it consumes revenue and does not provide direct earning. Kitchen ventilation is perceived as a “necessary evil” and is provided with the cheapest form to satisfy the plan or statutory requirements.
WHY DO WE NEED A VENTILATION SYSTEM IN COMMERCIAL KITCHENS ? 1. Remove excess heat immediately 2. Remove particulates of grease , odour, Toxic gases ... 3. Remove moisture 4. Renew the air that is being exhausted while maintaining Indoor air quality in the working space.
WHERE DOES THE HEAT GENERATED IN KITCHEN COME FROM ? 1. Convective Heat 2. Radiated Heat MAINLY FROM ‘COOKING PROCESS’ and COOKING EQUIPMENT. Convective heat can be captured by a hood. Radiated heat cannot be captured by any hood.
What happens when we don’t exhaust effectively ? EFFULENT AND HEAT SPILLS
Heat Gain Model Capturing Spilling Radiation Radiation Convection Radiation Radiation Radiation Radiation
Captured by SchlierenThermal Imaging SPILLING = Heat + Humidity + Toxic Gases
SPILLING ADDS SPILLING ADDS HEAT MOISTURE EFFLUENTS SUCH AS Carbon dioxide, Carbon monoxide, Sulphurdioxide, Nitrous oxide, oil fumes.
EFFECTS OF SPILLING Productivity Health There are several studies dealing with cooking and health issues. It is confirmed that cooking fumes contain hazardous components in both Western and Asian types of Kitchen.
Kitchen workers may be exposed to a relatively high concentration of airborne impurities and that they are potentially exposed to relatively high levels of mutagens and carcinogens.
EFFECTIVE REMOVAL Capturing
Advantages of GoodKitchen Ventilation System Avoids Health & Hygiene Risks Keep kitchen staff comfortable Prevents Fire Accidents in Kitchen Improves the Life of Kitchen Equipment Prevents food contamination
Kitchen Ventilation System consists of Kitchen Hood
KitchenVentilation System consists of • Centrifugal Blower
Kitchen Ventilation System consists of • Exhaust Ducting Exhaust Duct
Kitchen Ventilation System consists of • Make Up Air Unit
Kitchen Ventilation System consists of • Fresh Air Ducting Supply air grill
Energy Consumed • Kitchen Ventilation consumes 30% of Energy in a Restaurant. • 1 HP of Current consumed in a Commercial Kitchen costs Rs. 25,000 per annum. • An average Restaurant Ventilation consumes 20 Hp.
How do we save energy in Commercial Kitchen Ventilation • Selection of Right Kitchen Hood • Selection of Right Blower • Right Duct Designing • Selection of Right Fresh System • Demand Ventilation
Selection of Right Kitchen Hood • Maximum Hangover
Selection of Right Kitchen Hood • Maximum Capture Area
Selection of Right Kitchen Hood • Minimum Mounting Height
Selection of Right Kitchen Hood Side Panels Side (or end) panels or skirts permit a reduced exhaust rate in most cases, as more of the replacement air is drawn across the front of the equipment, improving capture of the effluent plume generated by the hot equipment. Another benefit of end panels is to mitigate the negative effect that cross drafts can have on hood performance.
Selection of Right Kitchen Hood • Minimum Filter Pressure Drop
Selection of Right Kitchen Hood • Avoid Dampers
Selection of Right Kitchen Hood • Insulation of Fresh Air Plenum
Selection of Right Kitchen Hood • Right collar sizing.
Selection of Right Kitchen Hood • Coanda Effect
Selection of Right Kitchen Hood • Capture Jet Concept
Selection of Right Kitchen Hood • Deflection Lip Concept
Selection of Right Kitchen Hood • Ultra Violet Filter Bank in Hood
Selection of Right Kitchen Hood • Spray mist concept
Selection of Right Blower • Backward Inclined Blades
Selection of Right Blower • Direct Drive
Selection of Right Blower • Low RPM of Motor
Selection of Right Blower • Performance Curve Efficiency
Selection of Right Blower • Discharge Orientation of Blower
Right Duct Design • Minimizing Bends
Right Duct Design • Large Radius for Bends Changes of direction should be by easy bends and well-rounded corners, not by sharp elbows, unless fitted with guide vanes.
Right Duct Design • Maintaining Right aspect Ratio
Right Duct Design • Proper Joints to avoid duct leakage
Right Duct Design • Suggest Angle Frames for Large Ducts
Right Duct Design • Proper sizing of Duct for Blower inlet connection
Right Duct Design • Proper sizing of Duct for Blower Outlet Connection
Right Duct Design • Proper insulation of Fresh Air Ducts
Right Duct Design Auxiliary items, such as grilles, louvers, filters. These items should be large enough to keep air velocities through them down to a reasonable level, consistent with the velocity in the main duct.