ebuildings assignment iii ricardosantos 79805 mit sesphd
TRANSCRIPT
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PhD Program on Sustainable Energy Systems 2013-14
Energy in Buildings (EB)
Assignment III
(Electric Loads in a building, Source: http://www.mech.hku.hk/)
Student
Ricardo Santos Nº79805
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CONTENTS
1 Introduction and objectives .................................................................................................3
2 case study, assumptions and Data used .........................................................................3
2.1 Building geometry ...................................................................................................................3
2.2 Construction details ................................................................................................................3
2.3 Glazings ..................................................................................................................................3
2.4 Internal gains: .........................................................................................................................3
2.5 Climate data used ..................................................................................................................3
2.6 Other assumptions/information used .....................................................................................4
3 Computational results ..........................................................................................................4
3.1 Building the simulation model.................................................................................................4
3.2 Part I .......................................................................................................................................5
3.3 With a climatization system ....................................................................................................6
4 Conclusions ....................................................................................................................... 18
5 Additional notes ................................................................................................................. 19
6 REFERENCES/ Bibliography ............................................................................................ 19
ANNEX 1 - Assumptions/considerations used ..................................................................... 20
ANNEX 2 - Tables used to define feed in tariffs .................................................................... 21
ANNEX 3 - Technical Features of luminair chosen .............................................................. 22
ANNEX 4 - Technical Features of Chiller chosen ................................................................. 23
ANNEX 5 - Technical Features of Boiler used ...................................................................... 24
ANNEX 6 - Technical Features of PV system used .............................................................. 25
ANNEX 6 - Technical Features of PV system used (cont.) .................................................. 26
ANNEX 7 - Technical Features of Bateries chosen .............................................................. 27
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1 INTRODUCTION AND OBJECTIVES
This works aims to study the thermal behavior of a building (school), by computing the thermal load,
energy needs, CO2 emissions, amoung other information, necessary to preform the study described before
as well as provide some alternatives to reduce the energy consumed by the building, and therefore the CO 2
emissions associated with it. The building is located at Lisbon on a specific date, and the computed values,
will have a resolution time of one hour, during a year.
2 CASE STUDY, ASSUMPTIONS AND DATA USED
2.1 Building geometry
For this porpuse, it was considered a small 2-storey school with the following geometry (Fig.1):
Fig.1 – Plant of floors 1&2 and East façade
The West façade is similar but without the door in the ground floor (it has a window like in the 1st floorinstead) and the the North and South facades are completely opaque. The Front door has 2*2.5 m.
2.2 Construction details
External wall (outin): cement coating (1cm) + insulation (4 cm) + light concrete (20 cm).
Internal walls: gypsum coating (2cm) + hollow brick (20 cm) + gypsum coating (2cm)
Ground and 1st floor slabs (all): cement coating (2cm) + light concrete (25 cm) + plastic tile (0.5 cm)
+ air layer (2 cm) + wood flooring (3 cm).
Roof slab:cement coating (2cm) + light concrete (25 cm) + XPS insulation (5 cm) + plastic tile (0.5
cm).
2.3 Glazings
Double clear glazing + internal venetian blind. The blind shades 70% of the window area, the other
30% remain unshaded.
20% of the glazed area is frame: 3 cm aluminum.
2.4 Internal gains:
20 students + 1 teacher per classroom, 9-18h.
2 computers + 1 videoprojector in the classroom (total: 320 W/room).
Lighting: 12 W/m2 constant between 9 and 18 h.
Air change:
Fresh air flow rates as per the requirements of RSECE, ensured by a mechanical ventilation system
with a fan of 1 kW.(http://www.adene.pt/ADENE/Canais/SubPortais/SCE/Legislacao/Nacional)
2.5 Climate data used
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For this purpose, it was used climate data from the program Solarterm1, which allows to extract data for
an entire year, mounth and hours, respectively, regarding (and for this case), the following data:
Outdoor temperature
Precipitation
Relative Humidity
Wind intensity and orientation
Solar radiation (global, reflective, difuse and global according to orientation)
Iluminance (global, direct, difuse)
Other relevant data
Therefore, it was considered the climatic data from the PRT_Lisboa.085360_INETI.epw , climatic file.
2.6 Other assumptions/information used
The school is closed in July and August and the Classroom 4 is located on the 1st
Floor of the
building.
On this work it wasn’t considered the latent loads.
The solar radiation, was split into direct and diffuse components, by using the information on global and
diffuse horizontal irradiation through the climate data file used.
Lisbon coordinates:
latitude: 38°42′49.72″N
longitude: 9°8′21.79″W
Outdoor temperature: 14ºC
Indoor temperature: 20ºC
3 COMPUTATIONAL RESULTS
For this porpuse, it was used the simulation software, namely the Energy Plus 8.1 (Ver_2.05), – tested
according to ASHRAE standards - to simulate the model built, which development stages are presented
next. The climate data used, is regarding the considered location (Lisbon), by using available data from
INETI data-base.
3.1 Building the simulation model
Geometry
In order to build the simulation model, first, it was designed the building geometry according to previous
section, by using Google Sketchup 8® software (VER 8.0.16846). On Fig.2, it is represented some of the
stages of the building design process (geometry stage).
Fig.2 – Building design process – building geometry
1 Available on LNEG -
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In this case, the EnergyPlus zones and surfaces, were created and edited by using the Legacy OpenStudio
Plug-in (ver.1.0.11), jointly with sketchup (Fig.3).
Fig.3 – Building design process – zone definition
With the geometry donne, the remain data to be inputed on the model through the Energy Plus file (created
by Legacy Openstudio plug-in), was introduced by using an .idf file editor (ver. 1.45).
Data set and model for deploym ent in Energy Plus
In order to complete the model, it was inputed on .idf file, the remain data regarding the building to be
simulated, whose materials and remaining features was presented before on Section 2.
The data inputed, was based on:
Building construction details
Internal gains
Climate data
Schedule occupancy
Other relevant data.
The climate data used, is regarding Lisbon location, from INETI climate data-base.
3.2 Part I
3.2.1 Running the model in free-float mode and draw an histogram (1ºC interval) of the
expected indoor temperatures in the occupied hours (i.e, a graph of hours per year in
each temperature) if the building doesn’t have an HVAC system.
By running the model, according to the data described before, it was obtained the results regarding the air
temperatures on the building in free-float mode condition (Fig.4).
Fig.4 –Expected indoor temperatures without the HVACT system
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The obtained results tells (at the begginning) that “ is more often” to have temperatures between 20 and 26
degrees, which could indicate more annual cooling energy needs than heating, regarding the building to
simulate. This is somehow explained by the values regarding Heating Degree Days (HDD) and Cooling
Degree Days (CDD) for Lisbon.
3.3 With a climatization system
By using the .idf file, it was addicted a HVACTemplate:Thermostat object to define the thermostat setpoints
for this simulation, where it was chosed a name for the thermostat, as well has defined the correspondent
setpoints, regarding heating and cooling, and another parameters according the process presented on Fig.5.
2-IDF,HVACTemplate:Zone:VAV
6 - IDF,HVACTemplate:Plant:Tower
3-IDF,HVACTemplate:System:VAV
1- IDF,HVACTemplate:Thermostat
5- IDF,HVACTemplate:Plant:Chiller
4- IDF,HVACTemplate:Plant:ChilledWaterLoop
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Fig.5 –Process of HVACT desing on Energy Plus through .idf file (Stages 1. 2 3 4 5 6 7 8 9)
Running the model in conditionned mode and made the same procedures on Section 3.2.1, i.e, drawing an
histogram with1ºC interval of the expected indoor temperatures in the occupied hours, then it is obtained the
following graph presented on Fig 6.
Fig.6 –Expected indoor temperatures with the HVACT system
The obtained results allows to show, that during the year, the indoor temperatures are maintained (in most
part of the time), between 20 and 25 degreees Celsius, as it was intended.
3.3.1 Minimum heating and cooling power that the HVAC system(s) must have to ensure
that in fact, under normal operation, it allows to maintain the building between 20 and
25 ºC.
The minimum heating and cooling values, were obtained by setting the HVAC thermostat values (from 20ºC
up to 25ºC), through the class “HVACTemplate:Thermostat” on idf file. The results, were obtained through
the corresponding spreadsheets, regarding the ouputs from EnergyPlus. Then it was preform the sum of
each hourly result, regarding each division of the building, in order to calculate the total load per hour.
9 - Sizing Parameters
8 - IDF,HVACTemplate:Plant:Boiler7- IDF,HVACTemplate:Plant:HotWaterLoop
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The summarized results regarding each room (Class room_1, Class room_2, Class room_3, Class room_4,
Class room_5, Class room_6, are presented as follows on Table 1.
Table.1 –Computed values regarding the building with a control temperature between 20ºC and 25ºC
Through the results presented above, the minimum heating and cooling values that the HVACT equipment
has to provide to maintain the temperature values between 20ºC and 25ºC, are the maximum valuescorresponding to heat and cooling loads, respectively:
:18800,20
:69260,79
Minimum Heating Power W
MinimumCooling Power W
3.3.2 The energy demand (needs) for heating, cooling, lighting, equipments and ventilation
(the fan). Express each separately, indicating what is thermal energy and what is
electricity (note that here heating and cooling refer to the needs of thermal energy, not
the consumption of an energy carrier).
The correspondent results are presented on Table 2,
Table.2 –Computed values regarding the building energy needs (regarding each considered dimension)
Through the results presented above, it is noticed that the energy needs for cooling is higher than the energy
needs for heating, which (in part) was expected, given the results presented on Section 3.3.1, regarding the
minimum cooling power preformed by the HVAC system to maintain the desired indoor temperature level,
between 20ºC and 25ºC.
For more detailed information about the values presented abouve, about the data treatment and other
issues, please see the excel in attachment to this report.
3.3.3 Assuming that heating is provided by a natural gas boiler with an efficiency of 85%
and cooling by a chiller with an average COP of 3,2, compute the monthly energy bill
of the school (m3 gas, kWh of electricity, and cost in € )
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It was assumed the existence of a natural gas boiler to heat up the building, as well as the existence of a
chiller also to cool it down. Both, were configured according to asked on this section (Fig.7).
Fig.7 –Configurations on Energy Plus file (.idf)
Both feed in tariff values, regarding natural gas and electricity respectively, were obtained from the
correspondent companies, where it was assumed to be the companies that provides natural gas and
electricity to the school, given his location (Lisbon) namely Lisboa Gas and EDP . Therefore, the used feeds
in tariffs were exctracted respectively from Tables A2.1 and A2.2 (Annex 2).
According to LIsboa Gas, the Natural GAS feed in tar iff, consists in the energy consumed (€/kWh) and also a
fixed daylly value, defined by the Portuguese Energy Sector Regulator Entity (ERSE).
The same, was assumed with electric feed in tariffs, according to [2].
Therefore, and for the total electrical feed in tariff calculation, it was considered a contracted power of 20,7kVA, giving therefore 0,8362 €/day (fixed tariff) and a 0,1543 €/kWh (varied tariff).
For the natural gas, it was considered a similar procedure, where from Table A2.1, it was selected the fixed
value, according to the hatural gas consumption rate of the building, 0,1819 €/day (“Escalão 4”), and the
correspondent varied tariff, 0,0651 €/kWh.
In order to convert the energy consumed into volume of natural gas, it was used the natural gas high
heating value (HHV) regarding the fuel features, supplied by Lisboagas. All this assumptions are presented
on Annex 1 of this report.
The final results, are presented on Table 3.
Table.3 –Computed values regarding the different building costs and the total CO2 emissions
By observing the values, it is noticed that as it expected, on July and August, since the building will be close,
there aren’t any CO2 emissions, since it is assumed that all the systems are turned off during that period.
It is also noticed that during the periods where the energy needs are higher (winter and autonm seasons),
the natural gas costs, necessary to supply the boiler to produce heat, will have more impact on the total cost,
Boiler Configuration Chiller configuration
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then in remaind periods, where the energy less needed to maintain the inddor temperature on the desire
level.
3.3.4 Using the conversion factors that follow compute the CO2 emissions associated to theoperation of this building during a year. Put in evidence the shares of contribution
from heating, cooling, lighting and equipments.
In order to put Energy Plus, to preform CO2 emissions calculations, it was necessary to configured the .idf
file, by making the changes presented on Fig 8.
Fig.8 –Configurations on Energy Plus file (.idf) to compute CO2 values
The results, regarding the CO2 emissions, associated to the operation of the building during a year, are
presented below, with the respective contribution shares, both from heating, cooling, lighting and
equipments.
Table.4 –Computed values regarding the CO2 emissions with the contribution shares
As it expected, the CO2 emissions, regarding heating are higher on periods that the outdoor temperature is
low, and therefore that is more needs in terms of energy to heat the building indoor to maintain the
temperatures to the desire level (20-25ºC). Therefore the CO2 emissions, will be more higher on this periods
(mainly November, December, January and February) than the remain ones, where energy cooling is more
needed. In the remain dimensions (light and equipments, there aren’t signficative changes).
On Fig.9, it is presented the annual share contribution of each individual dimensions in terms of CO 2 overall
emissions.
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Fig.9 –Share contribution of the different internal loads regarding CO2 emissions
It is noticed that most of CO2 annually emmited, is due to the light of the building, accounting 39,45 % of the
overall emissions, followed by the Heating (34,30%), Cooling (16,16%), and the Equipment (10,09%).
Part II
3.3.5 Playing with the bioclimatic concepts / measures that you learned (including lighting),try to decrease the thermal energy needs (not the consumption) for heating by > 20%compared to part 1, without increasing the needs for cooling by more than 20%.
Using bioclimatic measures and passive systems learned before, it was stablished xx measures to reduce
heating energy needs, according to some measures suggested by Gonçalves et al (2004) and by taking into
account the location of Lisbon in terms of Climatic zones defined by RCCTE (Portuguese law) – Zone I1-V2
(Table 5):
Table.5 –Strategic bioclimatic and passive systems reccomendations, applied to the building, according to his climatic
zone (Adapted from [m])
Wether season Bioclimatic stratagie Passive system
I. Winter
(Heating Season)
1. Promote solar gains
a. All gain systems are suitable,
according to the type of
building
2. Restrain Conduction losses a. Insulate the envolvent
3. Promote strong inertia a. Heavy walls with extrainsulation from the outside
II. Summer
(Heating Season)
1. Constrain solar gains a. Shading glass envelope
2. Constrain solar gains through
conductiona. Insulate the envelope
3. Ventilating
a. Longitudinal ventilating during
the night (nocturn)
b. Burried tubes
4. Promote strong inertiaa. Heavy walls with extra
insulation from the outside
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Based on the strategies presented on Table 5, it was considered the following measures, after exploit
several options2 presented on Table 6:
Table.6 –Strategic bioclimatic and passive systems reccomendations, applied to the building, according to his climatic
zone (Adapted from [m])
Strategie and passive(s)
system(s)
(based on Table 5)
Measure(s) adopted
I.1.a) Reduce shading by:
- decrease the slat angle of the shades by 20º
- Control the shading system (through slat angle) according to schedule
building occupation and outdoor temperature.
I.2.a) Increase the insulation glass by choosing triple glass windows, and
reduce the conductivity of the glass according to the manufacturer of
the window chosen; including argon gas since it presents less thermal
conductivity than air between the glass layers of the window.
I.3.a) Increase the envelope insulation by applying insulation through the
outside elements in the opaque envelope, where according to Ganhao
(2011), it’s an important procedure to reduce the heat flux conduction
through the walls. For this porpuse it was adopted ETIC3 insulation
material with a thicknes of 6 cm.
According to Ganhao (2011) the use of this type of insulation, is
justified by the high performance in terms of thermal positioning on the
elements, as well as on the correction of thermal plain bridges.
II.1.a) The same measure adopted on I.1.a)
II.2.a) The same measure adopted on I.3.a)
II.3.a)
Natural ventilating on Energy Plus, associated with the artificialventilating, included on bulding and controlled according to the
difference between outdoor and indoor temperatures.
II.4.a) By applying insulation through the outsider opaque envelope, where
according to Ganhao (2011), it’s an important procedure to increase
the thermal innercia of the walls, avoiding the heat losses during the
heating season, and decreasing the excessive solar gains during the
cooling season, for this porpuse it was adopted ETIC4 insulation with
a thicknes of 6 cm.
According to Ganhao (2011), the use of this type of insulation, is
justified by the high performance in terms of thermal positioning on the
elements, as well as on the correction of thermal plain bridges.
With all these measures implemented, it was obtained the following results, presented on Table 7.
2 For more information, see the correspondente .idf file (3.5)
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Table.7 – Adopted measures on behalf of bioclimatic context, applied to the building to decrease his energy needs5
Based on the obtained results, from Table 7, and those ones from Table 2, it can be preformed a
comparison between them, which results are summarized and presented on Table 8.
Table.8 –Comparison between the “Base Scenario” (Table 2) and the “New Scenario”, computed on this section
By observing the results from Table 8, it is noted that all the measures presented here, allows to decrease in
about 21,59% of energy needs in terms of Heating, as well as those regarding Cooling, where it was possible
to reach 13,25% less than the energy from “Base Scenario”.
3.3.6 Playing also with the HVAC systems, try to reach a solution (using equipments thatexist – documented by catalogues) that decrease the CO2 emissions associated withthe schools energy use by > 40% compared to part1.
In order to reduce the associated CO2 emissions (at least) by 40%, as it taken the following measures:
Improve light efficiency technologies – led instead of CFL technologies
More efficient HVACT (improved COP)
More Eficient boiler (increased boiler efficiency)
Fig.10 – Replacing on EnergyPlus with more effiecient HVAC and Boiler equipments
5 For more detailed information please see the excel file in attachment.
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Improve light efficiency technologies – led instead of CFL technologies
By assuming the existent lighting technology on the building as CFL6 lamps (given the initial power
density of 12 W/m2), it was decided to replace the lighting system with led technology, where according to
Ganhao (2011), a CFL can generate 52 lm/W approximately.
By assuming this, it was possible to estimate the total flux needed to ensure the lighting conditions interms of iluminance for a classroom for instance classroom 6, given his available area (12 m x 8 m= 96m
2).
By pretending to install a LED luminaire, presented on ANNEX 3 , whose lighting flux is 741 lm and hispower 7,3 W, it is obtained an LEDlight efficiency , by making:
Then the power regarding the lighting LEDS used, and his correspondent light power density, can becalculated by making:
Which is less then the previous value used on the building (12 W/m2).
More efficient HVAC (improved COP)
By increasing the performance coefficient (COP), form 3,2 up to 4,3, and reducing the cool capacity,according to the gains obtained from Section 3.3.5 in 13,25 %, the new minimal cool load capacity thatHVAC has to provide is 60083,73 W.Therefore, it was chosen the chiller presented on ANNEX 3.
More Eficient boiler (increased boiler efficiency) and reduced capacity.
Given the building location, and it’s climate zone, which allows to have more energy needs for coolingthan for heating, it was decreased the total capacity for the boiler down to 7000 W, rising at the sametime his efficiency from 0,85 (initial) to 0,9, and chosing a natural gas boiler, instead of electricity.
According to results obtained from Energy Plus,it was obtained the following results, regarding “CO2:Facility[kg](Hourly)” for each considered scenario:
BaseScenario (annual results from scenario considered on Section 3.3.4) = 37019,74 kg CO2
New Scenario (annual results): 26238,92 kg CO2
Therefore it was obtained a decrease rate of 41,09 %, between the Base Scenario and the New Scenario,with all the measures, described above.For more information, please see the attachment Excel f i le , where are presented all the results obtainedfrom EnergyPlus, regarding this question.
6 Compact Fluorescent Lamp
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3.3.7 Playing wStart from 3.6 and consider the hypothetical integration of renewable energymicrogeneration in the building. Propose a set of microgeneration equipments thatwould make the School a Carbon Neutral Building. Specify the size, power, and if
possible cost.
For the microgeneration system it was implemented a PY generation system, supported by batteries, and
PV panels with the following technical features:
Table.9 –Technical features
Sunmodule SW250 (Policristalline)
Maximum power (Pmax) [W] 250
Maximum power point current (Impp) [A] 8,27Maximum power point current (Vmpp) [V] 30,5
Short-circuit current (Isc) [A] 8,81
Open circuit voltage (Uoc) [V] 37,6
NOCT (Normalized operational temperature)(ºC) 46
Current Temperature Coeficient (TcIsc)[%/ºk] 0,081Voltage Temperature Coeficient (TcVsc)[%/ºk] -0,37
Cells per module 60
Length [mm] 1675,00
Width [mm] 1001,00
Pannel effciency [%] 15
According to PVGYS data base, and preforming the solar energy estimations regarding Lisbon (Fig.11)
Fig.11 – PVGis calculations
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A set of correspondent operating curves (dailly and month values) of solar irradiation and electric energy
produced are presented on Fig. 12.
a) b)
Fig.12 – PVGis solar and energy curves for a optimal inclination anghle of 35º according to PVGis
a) Solar monthly irradiation b) Monthly Energy produced (source: obtained from PVGis)
The correspondent values (dailly and month) of average solar irradiation and electric energy produced are
presented on Table 10.
Table.10 –Irradiacion values obtained form PVGIS
Where:
E d : Average daily electricity production from the given system (kWh)
E m: Average monthly electricity production from the given system (kWh)
H d : Average daily sum of global irradiation per square meter received by the modules of the given system
(kWh/m2)
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H m: Average sum of global irradiation per square meter received by the modules of the given system
(kWh/m2)
The dimensioning of the system was based on the following expressions:
The following assumptions, as well as the correspondent results froom the calculations preformed above, are
presented on Table 11.
Table.10 –PV system design
For more detail, please see the excel file (in attachment).
Although most of the electrical load of the school are concentrated on the schedule building occupation, itwas considered, a storage system based on batteries to supply the building during the periodes ofunavailable energy from PV system, or unsuficient energy from this system (night periods, periods with lessavailable solar radiation, etc).The design of the system were mad, based on the following expressures:
Where:
Nº of backup days (NDA) [typical 7 days]
Energy consumption for one cycle (EL)
Nº of days for one consumption cycle (NDCL)
Simultaneous factor of sun and load (FCSC)
System nominal voltage (Vn_sistema)
Empty factor (PDmax) [70%] Battery efficiency ( ηbat = 85%)
Battery capacity Cbaterias [Ah]
The following assumptions, as well as the correspondent results froom the calculations preformed above, are
presented on Table 11.
Table.11 –Batteries storage bank
For more detail, please see the excel file (in attachment).
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The total installation cost of the microgeneration system, are presented on Table 12
Table.12 – Costs regarding the production system
As it expected, the higher value, are due the PV modules, but if the consumer choose to sell the
coreepondent surplus to the grid, by connect the system, it might recovered some of the innitial investement
done it before.
4 CONCLUSIONS
By adopting some of the measures referred here on behalf of bioclimatic, such improve insulating and
ventilation, it can allow to reduce the building energy needs, as well as CO2 emissions, even by maintain the
indoor temperature at a desire level.
The same can be done by adopting other measures within the devices used on the building to improve
energy efficiency, even by using more efficient technology lamps, or by using a better efficient boiler to heat
up the building with less energy.
By using microgeneration technologies, it was possible to guarantee a zero carbon emissions from the
building, however, the costs are a barrier, that can be overcomed with economic and feasible solutions, like
on grid connection approach, which allows som return of the investment, even some gains, depending on the
system performance.
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5 ADDITIONAL NOTES
Other assumptions, or calculations that was not presented here, are shown on the Excell file,
which will be attached to this document by email to the Professor.
6 REFERENCES/ BIBLIOGRAPHY
ASHRAE (2009) ASHRAE Fundamentals, American Society of Heating, Refrigerating and Air-Conditioning
Engineers, US
Energy Plus (2013), Getting Started with EnergyPlus Basic Concepts Manual -Essential Information
YouNeed about Running EnergyPlus, US Department of Energy, USA
EPlus(2013), Guide for Interface Developers - EverythingYou Need to Know about EnergyPlus Input andOutput (todevelopauser-friendlyinterface), US Department of Energy, USA
Ganhão, A.(2011), Construção Sustentável - Propostas de melhoria da eficiência energética em edifícios de
habitação - Dissertação para obtenção do grau de mestre em Engenharia Civil, Faculdade Ciencias e
Tecnologia, Universidade Nova de Lisboa, Caparica
Gonçalves, H., Graça, J., M., (2004) Conceitos Bioclimáticos para os Edifícios em Portugal , INETI ISBN
972-8268-34-3, DGEG, Lisboa, Novembro
Rodrigues, A., Piedade, A., Braga, A.(2009), Termica de Edificios, Edições ORION, Lisboa
RSECE (2006) Decreto-Lei 79/2006 Regulamento dos Sistemas Energéticos de Climatização em Edifícios
(RSECE)
Santos et al (2006), dos Santos, P., Matias,L., “Coeficientes de Transmissão Térmica de elementos da
envolvente dos edifícios”, ICT informação técnica ITE50, INETI, Lisboa (in Portuguese).
Sites
/Software solterm LNEG - http://www.lneg.pt/iedt/projectos/370/ (accessed on 20/05/2014)
PVGis - http://re.jrc.ec.europa.eu/pvgis/apps4/pvest.php (accessed on 21/06/2014)
Windowshttp://www.mmaluminios.pt/pt/articles/vidro-isolar-neutralux2/vidro-isolar-neutralux#.U7CVu6hdVwc(accessed on 03/07/2014)
Galp Energia www.galpenergia.com/PT/ProdutosServicos/GasNatural/Mercado-Regulado/Tarifario/Paginas/Tarifario.aspx?tipoUtilizacao=1&empresa=4& (accessed on 03/07/2014)
EDP - https://energia.edp.pt/particulares/energia/tarifarios-2014.aspx (accessed on 12/07/2014)
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ANNEX 1 - ASSUMPTIONS/CONSIDERATIONS USED
CO2 emission factors :
Electricity: 350 g CO2/kWhf.e.
Natural gas = 2,2 kg CO2/m3 | 230 g CO2/kWhf.e.
1 J= 2,77778 x 10-7 kWh
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ANNEX 2 - TABLES USED TO DEFINE FEED IN TARIFFS
Table.A2.1 –Lisboagas feed in tariffs
Table.A2.2 –EDP feed in tariffs
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ANNEX 3 - TECHNICAL FEATURES OF LUMINAIR CHOSEN
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ANNEX 4 - TECHNICAL FEATURES OF CHILLER CHOSEN
Brand:Hidros Model:LDA
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ANNEX 5 - TECHNICAL FEATURES OF BOILER USED
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ANNEX 6 - TECHNICAL FEATURES OF PV SYSTEM USED
Inverter
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ANNEX 6 - TECHNICAL FEATURES OF PV SYSTEM USED (CONT.)
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ANNEX 7 - TECHNICAL FEATURES OF BATERIES CHOSEN