2.Pankaj Dharkar_Net Zero Energy Building (25-06-11,Delhi)
Presented by :
P. R. DHARKAR ISHRAE Past President
•
Geothermal Cooling Systems
•
Solar Air-conditioning Systems
•
DOAS Systems
•
Radiant Cooling Systems
•
Under floor Air-Distribution System
•
Two/Three Stage Evaporative cooling Systems
•
VAV Systems
•
VRV / VRF Systems
•
Variable Frequency Drives
•
Thermal Displacement Ventilation
•
Static Energy storage
•
Cogeneration
•Geothermal technology is relatively new in our country •Most energy-efficient and environmentally sensitive of all space conditioning systems. •Earth's constant temperature, approximately 55 degrees, is used to heat and cool a building. •Geothermal heat pump can save 30 to 50 percent in cooling costs compared to conventional systems. •Ground source heat pumps work by circulating water or a water/antifreeze solution through a closed loop of polyethylene pipe that is buried in the ground. • A closed loop system, can be laid out either vertically in 50-250 foot deep holes drilled like a well, or horizontally in 3-6 foot deep trenches. •The ductwork is no different than that of a conventional forced-air system. •Ground source heat pump can be teamed with a de superheater which can provide free hot water along with cooling.
3. The Lithium Bromide Vapor Absorption Machine works with hot water as input and delivers chilled water at 6-8°C as output.
#
$
5. The chilled water produced by the VAM is then circulated through the heat exchangers of fan coil and air handling units to cool the space.
1.The high efficiency evacuated tube heat pipe solar collector transfers the heat from the sun to the fluid flowing in the manifold.
"
4. The cooling tower ensures heat buildup is kept in check and maintains the system within operating temperature ranges.
2. The heat collected through the collectors is stored in the energy storage tank.
DOAS delivers preconditioned fresh air to individual space so as to remove all of the fresh air ventilation load and the space latent cooling load. Separate and parallel mechanical cooling system is used to remove the space sensible cooling load. The options available for internal cooling / heating are: • Terminal AHU / FCU • Unitary equipments like VRV / VRF system • VAV system • Chilled beams or ceilings Typical Make-up Air Unit Installation
Low Mass Radiant Cooling systems Low mass radiant systems circulate cool water in specialized panels or beams and typically operate during the occupied time. Eg-Chilled Beam System, Ceiling Radiant system.
High Mass Radiant Cooling systems High mass systems cool the building structure (slab, walls, ceilings) during unoccupied time and provide the additional advantage of off-peak cooling and further reduction in energy costs. Eg-Structural cooling
Structural cooling :
Direct Structure Cooling : It is a method of removing heat from the floor by laying a coil of plastic pipe between the slab screed and the tiling. The pipe is completely encased in the bedding. Water circulated in the pipes is cooled by a central chiller through a heat exchanger. Main Advantages : • It reduces the cooling load on the air system. • Cooler floor and ceiling reduces the Mean Radiant Temperature (MTR), enhancing the feeling of comfort for the same temperature and humidity • The heat is removed at a higher temperature by the chiller. Since the condensing temperature is the same, the power consumption is lower.
•The ceiling radiant system can be a cooling system and combined with a forced ventilation system •The pipes and the diffusers are hidden in the upper part of the false ceiling which controls the temperature on the surface. •The radiant systems keep an homogeneous well-being inside the room, •It minimizes the temperature differences either in the vertical direction or in the horizontal one. •Provides Increased thermal comfort and reduced noise levels. •Relevant energy savings are possible.
Chilled beams feature finned chilled water heat ex-changer cooling coils, capable of providing up to 1100 BTUH of sensible cooling per foot of length and are designed to take advantage of the significantly higher cooling efficiencies of water. The low plenum requirements of chilled beam systems make them ideal choices for retrofit of buildings . Large supply and return air ductwork can be replaced with small chilled water pipes. Advantages : • Savings in terms of plenum space and increases usable floor space. • Savings in huge amount of power consumption as Supply air temp is elevated as compared to conventional system • The Chiller can run on higher chilled water temp and hence saves power. • Reduced supply air flow rates result in lower fan energy consumption. • Ducting and its insulation is completely eliminated, which is again a saving. • Easy to maintain.
Space beneath raised floor is used as a distribution plenum or terminal units are installed beneath the raised floor and air is supplied at relatively elevated temperatures of 60 to 64 deg F by blending cold supply air with warm return air. Advantages : • Higher ceiling possible in every room that gives architect and interior designer good flexibility. • Cabin configuration can be changed without disturbing the AC system. • Savings in huge amount of power consumption as Supply air temp is elevated as compared to conventional system • The Chiller can run on higher chilled water temp and hence saves power. • Ducting and its insulation is completely eliminated, which is again a saving. • Easy to maintain.
Figure 1. Conventional overhead air distribution system
Figure 2. Under floor air distribution (UFAD) system
Palais Royale (Proposed Green Home) At Mumbai :
Height – 333 m Type – Residential Tower First ever LEED Platinum rating (Green Homes)
HVAC load –1711 TR HVAC System- Chilled Water System / VRF System Initial HVAC load – 2484 TR Fresh Air Optimization Building Envelope Optimization Lighting Optimization HVAC Optimization
Optimized HVAC load – 1711 TR
A Three Tier Cooling System proposed has three sets of Evaporators• High Temperature system for direct cooling • Medium temperature set for dry comfort cooling • Low temperature unit for fresh air & dehumidification. • The Energy efficiency of this system is much higher since the average evaporation is at about 15°C
Thank you
P. R. DHARKAR ISHRAE Past President
•
Geothermal Cooling Systems
•
Solar Air-conditioning Systems
•
DOAS Systems
•
Radiant Cooling Systems
•
Under floor Air-Distribution System
•
Two/Three Stage Evaporative cooling Systems
•
VAV Systems
•
VRV / VRF Systems
•
Variable Frequency Drives
•
Thermal Displacement Ventilation
•
Static Energy storage
•
Cogeneration
•Geothermal technology is relatively new in our country •Most energy-efficient and environmentally sensitive of all space conditioning systems. •Earth's constant temperature, approximately 55 degrees, is used to heat and cool a building. •Geothermal heat pump can save 30 to 50 percent in cooling costs compared to conventional systems. •Ground source heat pumps work by circulating water or a water/antifreeze solution through a closed loop of polyethylene pipe that is buried in the ground. • A closed loop system, can be laid out either vertically in 50-250 foot deep holes drilled like a well, or horizontally in 3-6 foot deep trenches. •The ductwork is no different than that of a conventional forced-air system. •Ground source heat pump can be teamed with a de superheater which can provide free hot water along with cooling.
3. The Lithium Bromide Vapor Absorption Machine works with hot water as input and delivers chilled water at 6-8°C as output.
#
$
5. The chilled water produced by the VAM is then circulated through the heat exchangers of fan coil and air handling units to cool the space.
1.The high efficiency evacuated tube heat pipe solar collector transfers the heat from the sun to the fluid flowing in the manifold.
"
4. The cooling tower ensures heat buildup is kept in check and maintains the system within operating temperature ranges.
2. The heat collected through the collectors is stored in the energy storage tank.
DOAS delivers preconditioned fresh air to individual space so as to remove all of the fresh air ventilation load and the space latent cooling load. Separate and parallel mechanical cooling system is used to remove the space sensible cooling load. The options available for internal cooling / heating are: • Terminal AHU / FCU • Unitary equipments like VRV / VRF system • VAV system • Chilled beams or ceilings Typical Make-up Air Unit Installation
Low Mass Radiant Cooling systems Low mass radiant systems circulate cool water in specialized panels or beams and typically operate during the occupied time. Eg-Chilled Beam System, Ceiling Radiant system.
High Mass Radiant Cooling systems High mass systems cool the building structure (slab, walls, ceilings) during unoccupied time and provide the additional advantage of off-peak cooling and further reduction in energy costs. Eg-Structural cooling
Structural cooling :
Direct Structure Cooling : It is a method of removing heat from the floor by laying a coil of plastic pipe between the slab screed and the tiling. The pipe is completely encased in the bedding. Water circulated in the pipes is cooled by a central chiller through a heat exchanger. Main Advantages : • It reduces the cooling load on the air system. • Cooler floor and ceiling reduces the Mean Radiant Temperature (MTR), enhancing the feeling of comfort for the same temperature and humidity • The heat is removed at a higher temperature by the chiller. Since the condensing temperature is the same, the power consumption is lower.
•The ceiling radiant system can be a cooling system and combined with a forced ventilation system •The pipes and the diffusers are hidden in the upper part of the false ceiling which controls the temperature on the surface. •The radiant systems keep an homogeneous well-being inside the room, •It minimizes the temperature differences either in the vertical direction or in the horizontal one. •Provides Increased thermal comfort and reduced noise levels. •Relevant energy savings are possible.
Chilled beams feature finned chilled water heat ex-changer cooling coils, capable of providing up to 1100 BTUH of sensible cooling per foot of length and are designed to take advantage of the significantly higher cooling efficiencies of water. The low plenum requirements of chilled beam systems make them ideal choices for retrofit of buildings . Large supply and return air ductwork can be replaced with small chilled water pipes. Advantages : • Savings in terms of plenum space and increases usable floor space. • Savings in huge amount of power consumption as Supply air temp is elevated as compared to conventional system • The Chiller can run on higher chilled water temp and hence saves power. • Reduced supply air flow rates result in lower fan energy consumption. • Ducting and its insulation is completely eliminated, which is again a saving. • Easy to maintain.
Space beneath raised floor is used as a distribution plenum or terminal units are installed beneath the raised floor and air is supplied at relatively elevated temperatures of 60 to 64 deg F by blending cold supply air with warm return air. Advantages : • Higher ceiling possible in every room that gives architect and interior designer good flexibility. • Cabin configuration can be changed without disturbing the AC system. • Savings in huge amount of power consumption as Supply air temp is elevated as compared to conventional system • The Chiller can run on higher chilled water temp and hence saves power. • Ducting and its insulation is completely eliminated, which is again a saving. • Easy to maintain.
Figure 1. Conventional overhead air distribution system
Figure 2. Under floor air distribution (UFAD) system
Palais Royale (Proposed Green Home) At Mumbai :
Height – 333 m Type – Residential Tower First ever LEED Platinum rating (Green Homes)
HVAC load –1711 TR HVAC System- Chilled Water System / VRF System Initial HVAC load – 2484 TR Fresh Air Optimization Building Envelope Optimization Lighting Optimization HVAC Optimization
Optimized HVAC load – 1711 TR
A Three Tier Cooling System proposed has three sets of Evaporators• High Temperature system for direct cooling • Medium temperature set for dry comfort cooling • Low temperature unit for fresh air & dehumidification. • The Energy efficiency of this system is much higher since the average evaporation is at about 15°C
Thank you
