4.492 Daylighting in Buildings Class01 · Coal fired boiler, manual feed Coal fired ... Gas heater...
Transcript of 4.492 Daylighting in Buildings Class01 · Coal fired boiler, manual feed Coal fired ... Gas heater...
Energy resourcesFossil fuels
Coal
Oil
Gas
Nuclear energy
Petroleum39%
Gas24%
Coal22%
Nuclear7%
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Energy resources
Renewable energiesWind
Coal22%
Nuclear7%
Renewables8%
Petroleum39%
Gas24%
Image by MIT OCW.
Energy resources
Renewable energiesWind
Solar thermal
Coal22%
Nuclear7%
Renewables8%
Petroleum39%
Gas24%
LATITUDE
LATITUD
E
LATITUDE + 15o-15o
1 2 3
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Energy resources
Renewable energiesWind
Solar thermal
Photovoltaic
Coal22%
Nuclear7%
Renewables8%
Petroleum39%
Gas24%
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Energy resources
Renewable energies storage issueWind
Solar thermal
Photovoltaic
Hydroelectric (& Tidal)
Coal22%
Nuclear7%
Renewables8%
Petroleum39%
Gas24%
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Energy resources
Energy conversion ElectricityElectric heating only half as efficient as direct fuel combustion
Coolwater in
Warmwater out
Waterway
CondensatePump
Fuel
Generator
SteamTurbineBoiler
Electrical Energy
Condensor
Conversion Device Efficiency, η
0.300.60
0.700.700.75
0.05-0.200.18-0.40
0.20-0.28
0.32-0.38
0.30-0.35
0.970.92
0.98
0.75
0.99
Open fireplaceCoal fired boiler, manual feed
Coal fired boiler, automaticOil fired boilerGas fired boiler
Steam piston enginesSteam turbines
Petrol engines
Diesel engines
Gas turbines
AC generatorAC motor
TransformerLead-acid battery
(input-output)
Electric heating
Chemical-to-heat
Heat-to-mechanical
Chemical-to-mechanical
Electrical
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Active controls: HVAC
Two parameters to be knowncapacity depends on building’s heat losses
depends on ΔT between comfort °T and worst outside °T
heating requirements depends on time of the year
Active controls: HVAC
Local heatingOil heater
Stove (solid fuel)
Gas heater
Electric heaterInfrared lamps
Incandescent radiators
Medium temperature (tube or panel) radiators
Low temperature panels (oil filled)
Convectors
Fan-convectors
Storage (block) heaters
Floor warming
Ceiling warming
TypeHeat emission (%)
Radiant Convective
100
100
80
80
80
60
6040
40
20
20
10
20
3070
90
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Active controls: HVACLocal heating
Oil heater
Stove (solid fuel)
Gas heater
Electric heater Heat pump
20
15
10
5
0-10 10 20 300
(Cold) Source temperature (oC)
(Warm) Sink (room) temperature (oC) 20304050
CO
P
CompressorHigh pressure
vapour
High pressure liquid Low pressure liquid
Low pressurevapour
Sink Source
Con
dens
er
Evap
orat
or
Choke (Pressure release valve)
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Active controls: HVAC
Central heatingAir based
Water based
Ret
urn
duct
Supplyducts
Burneroiltank
FanDust filter
Oil Tank
0,33 0,33 for
Control valveConvector
Air vent
Returnfitting Pump
Comtank
Boiler
h/m 3Kh/m 3K
pression
1161 kWh/m3K
kW
Air duct for
Water
1161 kWh/m3K
kW
Air duct
pipe
for
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Active controls: HVACVentilation and air-conditioning
Mechanical ventilation
Air-conditioning Conventional room conditioner Open-cycle cooling
Radiating surfaces
Outdoor air
Room air
CD
C M E
Sump with float valve for make-up water
Fibrous material pade.g. wood shavingsin cheese cloth
Perforated drip pipe
Pump MotorFan
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Active controls: HVAC
Integration and occupants’ comfortFloor warming slow but comfortable
Convectors quick but not for massive/badly insulated spaces
Local radiative heating towards people for large spaces
Passive and active heating combinationHeating system coherent with solar gains
stops when gains overcome needs
requires temperature or solar radiation sensor (separation N/S)
NS
SAF
AF
VMVM
VF
AF
VF
VM
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Passive and active heating combinationHeating system coherent with solar gains
stops when gains overcome needs
requires temperature or solar radiation sensor (separation N/S)
requires low inertia of heating system
[h]
Air
[h]
Radiator
[h]
Floor
0 2 4 6 8 10 12 14 16 0 2 4 6 8 10 12 14 16
0 2 4 6 8 10 12 14 16
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Passive and active heating combination
Heating system coherent with solar gainsstops when gains overcome needs
requires temperature or solar radiation sensor (separation N/S)
requires low inertia of heating system
autoregulation difficult with high temperature heating systems
Active Heating and Cooling
Reading assignment from Textbook:“Introduction to Architectural Science” by Szokolay: § 1.6 + § 4.1 - 4.2
Additional readings relevant to lecture topics:"How Buildings Work" by Allen: pp. 77 - 88 in Chap 10 + Chap 15
"Heating Cooling Lighting" by Lechner: Chaps 2 + 8 + 16
“The Technology of Ecological Building“ by Daniels: Chaps 10 – 12
More detailed information about renewable energy"Sustainability at the cutting edge – Emerging technologies for low energy buildings" by Smith