Results from the Application of the Maltese Energy Performance Rating of Dwellings in Malta EPRDM Software to a New Block of Apartments Charles Yousif Institute for University of Malta with Celia Pérez Garcia & Ignacio Gómez Royuela Universidad de Valladolid, Spain regulations, Aula Magna, Valletta 1
Contents Energy Use in Buildings Basic Principles of EPRDM Application to a new Block of Apartments Comparison to Design Builder Energy Plus Software Proposed Energy Rating Scale 2
Distribution of Energy Use (2008) Industry Residential Commercial Transport Other 32% 30% 4% EU 9% 28% 19% Malta 22% 11% 20% 25% 3
Aims of the Study to evaluate the results of the EPRDM software, when applied to a typical building block to identify specific areas where improvement of know-how or database may be required To compare results to those produced by Design Builder Energy Plus Software To attempt a first-hand energy performance rating scale for Maltese dwellings. 4
Existing Building Description Block of 9 apartments and 2 penthouses Total footprint 436 m 2 4 floors with 2 semi-basement and lower basement garage levels Orientation N23ºE 5
Building Elements BUILDING ELEMENT FAÇADE EXPOSED WALLS DESCRIPTION 180mm thick limestone blocks 30mm air cavity 180mm thick limestone blocks 230mm thick hollow concrete blocks ROOF 200mm thick reinforced concrete 50mm polystyrene insulation sheets 100mm crushed limestone 50mm screed 5mm Bitumen felt FLOOR 200mm thick reinforced concrete 100mm crushed limestone 6mm ceramic tiles APERTURES (FAÇADE) (OTHERS) 3mm double laminated clear glass 6 mm air gap Aluminum frame 3mm single clear or frosted glass Aluminum frame 6
The EPRDM Is the Maltese calculation tool for Energy Performance Rating of Dwellings using MSA EN 13790:2008. Single-zone Calculation Based on the energy balance on a monthly basis 7
EPRDM Pre-settings: Heating Zone temperature of 18.2 depends on utilisation factor of 40% with Living area temp. set at: 23ºC Rest of dwelling: 15ºC Electric Heater COP = 1 A/C covering more than 40% of internal footprint COP 2.8 or as registered 8 hours daily operation 8
EPRDM Pre-settings: Cooling Zone temperature of 26.8 depends on utilisation factor of 40% with Living area temp. set at: 25ºC Rest of dwelling: 28ºC A/C if covering more than 40% of internal footprint COP 2.8 or as registered 8 hours daily operation 9
EPRDM Pre-settings: Occupancy 1 person per 60 m 2 Minimum 2 people Maximum 7 people Heat gains: 1.2 W/m 2 from occupants 1.5 W/m 2 from appliances 10
EPRDM Pre-settings: Water Heating 35 litres per person per day Water heated to 60ºC Electric water heater COP = 1 Heat losses from water storage at 15% 11
EPRDM Pre-settings: Ventilation Data input by the assessor No. of Chimneys (>100 mm Dia.), open flues, intermittent fans and passive vents, fluelessgas fires, lobbies and storeys. If no previous air permeability test: Percentage of windows draught-stripped Percentage of party walls 12
EPRDM Pre-settings: Lighting Takes into consideration energy efficient lighting systems and glazing ratio 13
EPRDM Pre-settings: Output Final energy electricity efficiency: 28% Carbon dioxide emissions: 0.878 kg / kwh 14
Design Builder Modelling environment virtual building models. International software adapted to the different international regulations. Databases of weather data, building materials, constructions, windows. Uses the EnergyPlusdynamic simulation engine to generate performance data (multi-zone calculation). Simulation for modelling building heating, cooling, lighting, ventilating and other energy flows. 15
Recombine whole building Energy use of heating, cooling and ventilation systems (systems 1) SOFTWARE Recombine zones per system (systems 1) Same for (systems 2) SYSTEMS 1 SYSTEMS 2 System losses and auxiliary energy use Energy needs for ZONE heating and cooling (zone 1) 1 Heat transfer rates and heat/cold sources ZONE Same for (zone 2) 2 Same for (zone 2) ZONE 3 Same for (zone 3) Same for (zone 3) Assessment of overall energy use and energy rating Partitioning of building into zones of calculation Building boundaries Project data Systems data 16
Results: Comparison of actual U-values (W/m 2 K) to the minimum requirements 0.574 OK 2,33 1.518 OK 5.47 OK 1,656 other external walls: 2.076 (shafts, yards,..) parts of upper floor roofs that are exposed due to the retraction of penthouses above them: 2.33 17
Results: Final Energy for Heating 18
Results: Final Energy for Cooling 19
Possible Sources of Differences Different weather data Wind effect Shading Factor Material properties Walls and windows orientation Internal gains 20
Results: Final Energy for Water Heating 21
Results: Final Energy for Lighting 22
Summary Result: Total Final Energy 23
Detailed Study for Possible EE Measures 24
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56% All light fittings are compact fluorescent lights Electric resistance water heating 30000 25000 20000 15000 10000 5000 0 Electric resistance water heating Space heating Primary Energy (kwh/m^2 yr) 67 % 7 % Space cooling Thermal comfort is strongly affected by the winter rather than the summer season. 18 % Water heating Pumps, fans 8 % Lighting TOTAL 70% Electric resistance water heating GROUND FIRST SECOND PENTHOUSE Solar water heating No energy saving bulbs installed. 50% University as energy Campus, saving Malta 26
Double Glazing Energy Efficiency Potential 18915.79 18109.81 PRIMARY ENERGY (kwh/m^2 yr) 3.2% The building has some energy deficiencies that could be All double glazing mitigated by the introduction of basic renovation measures. Ground floor without change 395.83 389.71 Insulation Floor 4896.15 907.83 898.08 25105.85 24303.5 Space heating Space cooling Water heating Lighting TOTAL Ground floor without change PRIMARY ENERGY (kwh/m^2 yr) 13.76% Insulation floor U-value improved from 1.656 W/ m 2 K to 0.493 W/ m 2 K 18915.79 15442.51 Heat Pump 25105.85 21649.05 412.31 395.83 4896.15 898.08 PRIMARY ENERGY (kwh/yr) Space heating Space cooling Water No low heating lighting installed Lighting All TOTAL low energy installed 12.93% 20360.38 19471.16 13197.86 11135.55 517424.23 Space heating Space cooling 4896.15 Water heating 3811.68 952.92 27 TOTAL Lighting
Double Glazing 3.13% PRIMARY ENERGY (kwh/m^2 yr) First floor without change All double glazing 13197.86 12584.77 19471.16 18861.98 424.23 421.69 Heat Pump Heat 4896.15 Pump 952.92959.37 PRIMARY ENERGY (kwh/m^2 yr) Space heating Space cooling Water heating Lighting TOTAL First floor wihout change Heat pump 16.67% 19471.16 16207.05 4896.15 1632.05 Water heating TOTAL 28
Double Glazing 13530.04 13027.99 PRIMARY ENERGY (kwh/m^2 yr) Second floor without change Ceiling Insulation All double glazing 23398.8 22896.03 PRIMARY ENERGY (kwh/m^2 yr) Second floor 1962.99 4896.15 without change Ceiling insulation 3029.12 1942.77 3009.62 Space heating Space cooling Water heating 13629.24 Lighting TOTAL 13530.04 1962.99 1649.88 2.15% PRIMARY ENERGY (kwh/m^2 yr) Second floor without change Exteranl walls insulation Heat Pump 3009.62 23398.8 19165.62 PRIMARY ENERGY (kwh/m^2 yr) 4896.15 U-value from 2.076 W/ m2 K to 0.578 W/ m2 K 13530.04 Space heating Space cooling Water heating Lighting TOTAL 9495.54 0.9% 23398.823184.89 U-value from 2.326 W/ m2 K to 0.595 W/ m2 K External walls insulation 1962.99 4896.15 1764.31 3009.62 Second floor wihout change Heat pump 18.09% 13.95% Space heating Space cooling Water heating Lighting TOTAL 23398.8 20134.7 4896.15 1632.05 Water heating TOTAL 29
Double Glazing PRIMARY ENERGY (kwh/m^2 yr) Penthouse wihout change All double glazing 2.24% 13195 12831.18 3609.07 3523.73 PRIMARY ENERGY (kwh/m^2 yr) 2461.54 18.09% Penthouse 2450.87 without change 282.96 19537.9 19099.41 External walls insulation U-value from 2.326 W/ m2 K to 0.595 W/ m2 K Space heating Space cooling Water heating Lighting TOTAL Exteranl walls insulation 19537.9 13195 8002.17 3609.07 3321.87 2450.87 282.96 14057.87 Solar Photovoltaic System Space heating Space cooling Water heating Lighting TOTAL 53.35% 30
Improvements to the EPRDM Rating 300 30% kwh/m^2 year 200 100 20% 42% 89% 0 Ground Ground (with EE changes) First First (with Second EE changes) Second (with EE changes) Penthouse Penthouse with EE changes 31
The Proposed EPRDM Rating EP Rating A B C D E F G Ground Floor Actual Potential 273.8 191.5 EP Rating A B C D E F G First Floor Actual Potential 201.3 161.3 EPRDM Rating A B kwh/ m^2 year 20 50 H A B C 0 100 200 300 400 EPRDM (kwh/m^2 year) Second Floor Actual Potential H A B C 0 100 200 300 400 EPRDM (kwh/m^2 year) Penthouse Actual Potential 16.5 C D E F 100 150 200 250 EP Rating D E F G 241.9 141.0 EP Rating D E F G 153.5 G H 300 400 H H 0 100 200 300 400 EPRDM (kwh/m^2 year) 0 100 200 300 400 EPRDM (kwh/m^2 year) 32
Improvements to the DCER Rating 80 60 kg CO2/m^2 year 40 20 0 Ground Ground (with EE changes) First First (with EE changes) Second Second (with EE changes) Penthouse Penthouse with EE changes 33
The Proposed DCER Rating DCER Rating A B C D E F G H Ground Floor Actual Potential 69 48 DCER Rating A B C D E F G H First Floor Actual 51 Potential 41 DCER Rating A kg CO2/ m^2 year 10 0 20 40 60 80 100 DCER (kg CO2/m^2 year) 0 20 40 60 80 100 DCER (kg CO2/m^2 year) B 20 DCER Rating A B C D E F G H Second Floor 0 20 40 60 80 100 DCER (kg CO2/m^2 year) Actual 61 Potential 35 DCER Rating A B C D E F G H Penthouse 0 20 40 60 80 100 DCER (kg CO2/m^2 year) Actual 39 Potential 4.2 C D E F G H 30 40 50 60 70 80 34
Observations in the EPRDM Software EPRDM software is stable and produces reasonable results EPRDM has problems of flexibility and accuracy in terms of data input The EPRDM does not take into account the energy consumption of typical appliances into consideration Workings made for the EPRDM Application are not easily understood for external people Limitation in choosing the orientation of the elements of the building (only 9 directions available) Does not account for convection heat losses due to the effect of wind. Does not consider the effect of thermal mass on energy performance. 35
Observations in the EPRDM Software Assumes generous living area per occupant for flats (60m 2 /person), which is probably based on the traditional terraced houses. Effect of shading by vertical walls is not well defined. The EPRDM does not take into account the energy consumption of appliances; Workings of the EPRDM Application are obscure for the external reviewer or the client The EPRDM certificates are valid for 10 years, but these may become invalid soon due to installation of new power station and would require an update to reflect the new realities in the electricity generation sector 36
Conclusions Energy Efficiency: Insulation of roofs and single walls are top ranking, while double glazing seemed to rank lowest, probably due to the mild Mediterranean climate in winter Renewable Energy: Solar heating, heat pumps and photovoltaicsrank highest, which calls for a stronger implementation of these technologies in the residential sector. But this may give a false indication of a good design, because RE systems would only cover up an otherwise wasteful dwelling Consumption data within typical buildings, to establish benchmarks for the EPRDM ratings. It is suggested that such classification is not carried out purely on the EPRDM rating but it would combine the building s actual compliance to the established minimum energy efficiency requirements, the annual energy consumption and the EPRDM rating; 37
Conclusions The proposed EPRDM and DCER ratings are subject to adjustment as more and more sample dwellings are sampled. The essential part is that the best and worst ratings are realistic and may occur in particular cases. The four dwellings showed that they differ in their rating and this reflects the variations in their building construction, quite reasonably. Design-Builder results compare quite well with EPRDM and could be used for cross-checking. However, it lacks specific data for Malta. 38
THANK YOU charles.yousif@um.edu.mt 39