Ask The HvacMan
Air Grilles
Air Diffusers
Air Quailty
All Air Systems
All Water Systems
Boilers
Building .Managament Systems ..BMS
Burners
Chillers
Cooling Towers
Cooling Load Calculation
Cryogenics
Energy Saving
Duct
Duct ,Smacna
Dampers ,Air
Dust Collection
Fans
Fire Dampers
Glass Selection
Heating
Heat Exchangers,water
Heat Recovery
Heat Tracing Systems
Hepa Filters
Hvac Applications
Humidifiers / Dehumidifiers
Insulation , Duct
Insulation , Pipe
Insulation , Sound
Nano Tech.,In Building
Occupancy Sensors
Pneumatic Conveying
Piping
Pool Ventilation
Process Piping
Psychrometry
Pumps
Radiant Heating
Refrigerant Systems
Solar Collectors
Sound
Steam Generation
Tables & Charts Gnr.
VAV Sytems
Valves
Ventilation
VRV Systems
STORE
Solar Collectors
Flat Plate Collectors
Evacuated Tube Collectors
Concentrating Collectors
Transpired Collectors
Solar Control Systems
Standalone Systems
Grid Connected Systems
Hybrid Systems
Back-up Systems
Solar Cells
Solar Arrays
Inverters
Change Controller
Turbines
Hybrid Systems
Grid Systems
Water Pumping
Using Wind Energy
Enviromental Aspects
Buyer's Guide
 
Save Energy
Solar Water Heating
Solar Electric Systems
Wind Turbines
Passive Solar Heating
Passive Solar Cooling
Building Material
Water Conservation
Ground Source Heat-Pumps
Green Hotels

Glass &Windows Selection

HEAT RECOVERY

 

Energy Recovery Systems

Energy Efficiency and Energy Recovery

Fresh air is essential to healthy people – and healthy buildings. That’s why commercial buildings are required to bring in fresh air – typically 15-20 cubic feet per minute (cfm) for every occupant. This unconditioned air greatly increases your building’s air-conditioning load – and since an equal amount of air must be vented outdoors, you’re basically “throwing away” air you’ve paid to cool.

Energy recovery ventilation systems – or “ERVs” – help reduce this waste and lower your energy costs. What’s more, an FPL incentive program now helps businesses pay for this technology – so you can save even more when you install a qualifying ERV unit on a new or existing HVAC system.

Energy recovery systems typically incorporate heat exchange equipment to reduce energy costs by extracting heat from the facility's exhaust air stream before it is vented outside. Energy recovery from the laboratory's exhaust should be considered when significant portions of operating hours are at ambient temperature of 50°F (10°C) and below. Another recoverable energy source is provided by chiller/DX condensers. Water cooled condensers can be piped to reject waste back into the labs HVAC system to provide reheat capacity, to augment run-around coil systems, and to dry regenerative heat wheels. When properly designed, these energy recovery systems can reduce installed HVAC system capacity by one-half; reduce operating energy from one-third to two-thirds, depending upon mode of operation; and have life-cycle cost paybacks from immediate to three years. The four major energy recovery systems include run-around coil systems, regenerative heat wheels, heat pipes, and fixed-plate exchangers

Plate heat exchangers (recuperators)

A minimum effectiveness of 50% (based on sensible energy transfer under balanced flow conditions).
Internal leakage < 1% (for units >0.2m3/second rating)
Pressure drop <250 Pascal (Pa) NOTE: where pressure drop data is not documented, the fan power consumption must be consistent with a pressure drop within this limit.

Thermal wheels

A minimum effectiveness of 70% (based on sensible energy transfer under balanced flow conditions).
Internal leakage < 5%
Pressure drop <200 Pa

Run around coils

A minimum effectiveness of 45% (based on sensible energy transfer under balanced flow conditions).
Pressure drop <100 Pa across each coil
Water side pressure drop < 25 kPa per coil

Heat pipes

Disadvantages of Energy Recovery Ventilation.

Unlike air handling units on unit ventilators, energy recovery systems do not have the capability to provide sufficient outside air for cooling overheated rooms. This can lead to overheating, especially in the late spring and early fall. Any building employing energy recovery ventilation should have a by-pass sytem for ERV 's or operable windows (or air conditioning) to provide cooling during warm weather.

Energy recovery ventilation is not a good choice for interior spaces unless those spaces are air-conditioned.

A second area of concern involves the fact that there is little standardization in the heat recovery industry. Manufactures and products come and go, and there is some concern that products specified today may not have manufactures' support a few years from now.

Heat exchangers to recover heat increase the pressure drop of the air handling system, and increase the power demand of the fans.
This is however typically only 5-10 % of the recovered energy.

Air to Air heat Recovery System Manufacturers

 

To qualify for ERV incentive your system must:

• Be an enthalpy wheel or plate type ERV system which recovers both sensible and latent heat from the building exhaust.
• Control humidity using either desiccant or moisture transfer membranes.
• Be listed on the ARI Web site (www.ari.org) with at least a 50% total cooling effectiveness rating.
• Be installed by an FPL Participating Independent Contractor (for HVAC systems smaller than 65,000 BTU/hour).
The amount of your incentive will be based on the size and efficiency of the ERV unit, as well as the heating type for the HVAC system.

These programs are subject to modification or cancellation at any time with notice. Final eligibility requirements are specified in the program standards.


 

 

 

 
Google
 
Web www.iklim.com
  Discuss on the Message Board
   
 
  http://www.iklimnet.com
 
Heat Recovery
Run-Around Coils
Plate HeatExchangers
Heat Wheels
Heat Pipes
 
Hotels
Enviroment
Legionnare Disease
Energy Saving
Control Software
Hotel Design Books

Hotel Design