UPDATE OF THE APPLICATION IN ITALY OF THE ......Update of the application in Italy of the method for calculating cost-optimal levels for minimum energy performance requirements (Directive

ENER-2018-288-00-01 (IT-EN)

Ministry of Economic Development

Directorate-General for the Electricity Market, Renewables and Energy Efficiency, and Nuclear

Energy

UPDATE OF THE APPLICATION IN ITALY OF THE METHOD

FOR CALCULATING COST-OPTIMAL LEVELS FOR MINIMUM

ENERGY PERFORMANCE REQUIREMENTS

(DIRECTIVE 2010/31/EU ARTICLE 5)

March 2018

Update of the application in Italy of the method for calculating cost-optimal levels for minimum energy performance requirements (Directive 2010/31/EU - Article 5)

2

NOTES

The Ministry of Economic Development has set up a working group to update the comparative

analysis method provided for in Article 5 of Directive 2010/31/EU. The group follows the

appropriate guidelines in compliance with Regulation (EU) No 244/2012 of 16 January 2012.

The following entities have taken part in the working group, coordinated by the Ministry of

Economic Development: ENEA (Agenzia nazionale per le nuove tecnologie, l'energia e lo sviluppo

economico sostenibile), the Italian Thermal Engineering Committee (Comitato Termotecnico

Italiano, CTI), the Polytechnic University of Turin (Politecnico di Torino) and the Polytechnic

University of the Marches (Università Politecnica delle Marche).

P. Signoretti, D. Iatauro, C. Romeo, L. Terrinoni - ENEA

R. Nidasio, CTI

V. Corrado, Polytechnic University of Turin

G. Riva, Polytechnic University of the Marches


3

CONTENTS

1. INTRODUCTION ................................................................................................................................... 4

2. MAIN NEW FEATURES INTRODUCED AND STRUCTURE OF THE WORK .......................... 4

3. ESTABLISHMENT OF REFERENCE BUILDINGS ......................................................................... 5

4. ENERGY EFFICIENCY MEASURES ............................................................................................... 10

5. DESCRIPTION OF MODEL FOR CALCULATING ENERGY PERFORMANCE .................... 12

6. ASSESSMENT OF COSTS OF ENERGY EFFICIENCY MEASURES ......................................... 13

7. FRAMEWORK OF CALCULATION PROCEDURE ...................................................................... 14

8. REPRESENTATION OF PROCESSING AND RESULTS .............................................................. 16


4

1. INTRODUCTION

The Energy Performance of Buildings Directive (‘EPBD’, Directive 2002/91/EC), and the recast

EPBD (Directive 2010/31/EU) introduced the principles for improving the energy performance of

buildings.

The recast EPBD required the Member States to define the minimum energy performance

requirement for buildings on the basis of cost-optimal levels. To this end, the Directive introduced a

method of comparative analysis for determining the reference requirements for national standards.

The Delegated Regulation (EU) No 244/2012 and the subsequent Commission Guidelines of

19 April 2012 set out a methodology framework for calculating the optimal energy requirements of

buildings, from both a technical and an economic point of view.

The application in Italy of the method proposed by the Commission has made it possible to identify

minimum energy performance requirements based on cost-optimal levels for new buildings and for

existing buildings undergoing major or minor renovation of structures and installations.

These requirements were introduced into Italian law by Decree of the Minister for Economic

Development of 26 June 2015.

The report entitled ‘Methodology for calculating cost-optimal levels of minimum energy

performance requirements (Article 5(2) of Directive 2010/13/EU)’ sent to the Commission in

August 2013 presented the results of these calculations and compared them with the requirements in

force.

This document aims to present the principles and rules that are being followed to update the

comparative analysis methodology, which must be reported at regular intervals of no more than

five years (Article 5 of Directive 2010/31/EU).

2. MAIN NEW FEATURES INTRODUCED AND STRUCTURE OF THE WORK

The update of the comparative methodology currently underway introduces some new features

since the assessments made in 2013, aimed at refining the analysis in the light of experience and

making it more effective in achieving the objective. The following new features are planned:

1. Introduction and assessment of the assumption of not carrying out measures on existing

buildings. As a result of this assumption, in the technical/economic assessment of energy

efficiency measures (EEM), for existing buildings the overall costs of measures will be taken

into consideration, not the reduced costs if work were done in a ‘window of opportunity’. In that

case only costs relating to simple energy efficiency measures could be considered in so far as

they were carried out at the same time as unplanned maintenance work, which had to be done in

any case. This additional assessment makes it possible to calculate a more realistic amount of

investment and to propose optimal levels closer to common practice, and to give more accurate

indications for the purpose of assessing whether or not it is financially worthwhile to take steps

to improve the energy efficiency of buildings.

2. Establishment of a new intended use among the reference buildings. The assessments will be

carried out for the reference buildings previously examined and also for a school building

representative of the period 1946-1976, located in Italian climatic zones B (601-900 degree-

days) and E (2101-3000 degree-days).

3. More specific and accurate assessment of thermal bridges for both new and existing buildings.


5

4. The energy performance of the reference buildings will be assessed using the semi-stationary

calculation method according to Italian standard UNI/TS 11300. The updated version of the

comparative analysis method will use the latest technical specifications (for years 2014-16);

similarly, the climate data will refer to the new technical standard UNI 10349-1:2016.

5. Change in levels of energy efficiency measures (EEM). The types of action/measure considered

will be the same as those used in the 2013 assessment, although in some cases the number of

levels examined and/or their intensity (scale of values) will be changed.

6. Updating of overall costs. The main changes will concern the cost values of energy carriers

(methane gas and electricity) and of investment in energy efficiency measures (EEM).

As in the 2013 exercise, for application of the comparative method, optimisation will be based

on seeking partial optimums, using a sequential process and considering individual solutions. In

order to identify the optimal energy efficiency measures package incurring the lowest overall

cost over the life cycle of each reference building, the procedure will assess the annual energy

consumption for heating, domestic hot water production (DHW) cooling and lighting (in the

case of non-residential buildings) of the building, and the use of renewable energy sources (heat

pump, solar thermal for DHW production and photovoltaic) and the overall costs (maintenance,

operating costs and any disposal costs).

The work will be structured in the following stages:

A. Characterisation of reference buildings

a. Residential buildings

b. Office buildings

c. School buildings

B. Development of the package with integrated spreadsheets

a. Calculation of energy performance

b. Calculation of overall cost

c. Optimising instrument

C. Analysis of the energy efficiency measures and the relative levels

a. Measures relating to the building envelope

b. Measures relating to installations

D. Cost analysis

a. Investment costs

b. Energy costs

c. Other costs

E. Identification of cost-optimal levels of energy performance

F. Sensitivity analysis

G. Comparison with results obtained in 2013

3. ESTABLISHMENT OF REFERENCE BUILDINGS

In the comparative analysis as applied by Italy and sent to the Commission in August 2013, the

reference buildings used were virtual buildings, i.e. representative archetypes of a given category.


6

For this purpose we referred to the TABULA project database for existing residential buildings,

while for new buildings and office buildings we used the types defined by ENEA.

In the updated methodology, alongside the four types of building already analysed, a school

building is newly introduced, situated in two climate zones (B and E, in accordance with

Presidential Decree 412/93).

Therefore three types of residential building will be analysed (single-family dwelling, small and

large apartment block), an office building and a school building (new case study), located in Italian

climate zones B (601-900 degree-days) and E (2101-3000 degree-days. Residential buildings and

office buildings cover two categories of measure: existing buildings (divided in two different time

periods: 1946-1976 and 1977-1990) and new construction; the school building is representative of

the 1946-1976 period. A total of 26 case studies will be analysed, including 18 residential buildings

(six new and 12 existing) six office buildings (two new and four existing) and two existing school

buildings.

INTENDED USE

TYPE OF BUILDING

CONSTRUCTION PERIOD

CLIMATIC ZONE CASE

STUDIES B E

RESIDENTIAL

Single-family house

(RMF)

Existing 1946-1976 (E1) 1 1

18

1977-1990 (E2) 1 1

New (N0) 1 1

Small apartment

block (RPC)

Existing 1946-1976 (E1) 1 1

1977-1990 (E2) 1 1

New (N0) 1 1

Large apartment

block (RGC)

Existing 1946-1976 (E1) 1 1

1977-1990 (E2) 1 1

New (N0) 1 1

TERTIARY SECTOR Office buildings

(UFF)

Existing 1946-1976 (E1) 1 1

6 1977-1990 (E2) 1 1

New (N0) 1 1

SERVICES School buildings

(SCU) Existing 1946-1976 (E1) 1 1 2

TOTAL 26

Table 1 - Case studies

The following tables summarise the geometric/dimensional characteristics of the building models

and the thermal/physical parameters that make up the building envelope by type, by construction

period and by climate zone.

The residential building models correspond to the following types of building:

single-family house consisting of a single floor;


7

small apartment block of 3 floors, with 6 housing units;

large apartment block of 8 floors, with 24 housing units.

These buildings have the form of a regular box and are equipped with a loft (not heated), with

insulated roof, and they stand on a non-air-conditioned space (a garage, for example).

ID of building

GEOMETRIC DATA CONSTRUCTION DATA

CL

IMA

TIC

ZO

NE

Af Vg A env A w A env/Vg hn,interp No of floors

No of units

U wall U w U roof/uf Ulf

[m2] [m3] [m

2] [m

2] [m-1] [m] [-] [-] [W/m2 K] [W/m2 K] [W/m2 K] [W/m2 K]

RMF_E1

162 583 437 20 0.75 3.00 2 1

1.18 4.90 2.20 2.00 B

1.48 4.90 2.20 2.00 E

RMF_E2

199 725 519 25 0.72 2.70 2 1

1.10 2.80 2.20 1.30 B

0.76 2.80 1.14 0.98 E

RMF_N0

97.5 371 368 12.6 0.99 2.70 1 1

B

E

Table 2 - Principal data of residential reference buildings - single-family house


8

ID of building


CL

IMA

TIC

ZO

NE


No of units


[m2] [m3] [m

2] [m

2] [m-1] [m] [-] [-] [W/m2 K] [W/m2 K] [W/m2 K] [W/m2 K]

RPC_E1

827 3076 1576 150 0.51 3.00 3 12

0.90 4.90 1.65 1.30 B

see original

for picture 1.15 4.90 1.65 1.30 E

RPC_E2

1088 4136 1994 121 0.48 2.70 3 12

0.98 3.70 1.65 1.60 B

see original

for picture 0.80 3.70 0.97 1.14 E

RPC_N0

450 1728 1032 64.8 0.60 2.70 3 6

B

see original for picture E

Table 3 - Principal data of residential reference buildings – small apartment block

ID of building


CL

IMA

TIC

ZO

NE


No of units


[m2] [m3] [m

2] [m

2] [m-1] [m] [-] [-] [W/m2 K] [W/m2 K] [W/m2 K] [W/m2 K]

RGC_E1

1552 5949 2740 217 0.46 3.00 4 24

0.90 4.90 1.65 1.30 B

see original

for picture 1.15 4.90 1.65 1.30 E

RGC_E2

3506 12685 4721 363 0.37 2.70 6 48

0.98 3.70 1.65 1.30 B

see original

for picture 0.76 3.70 0.97 0.98 E

RGC_N0

1788 6662 2834 257 0.43 2.70 8 24

B

see original

for picture E

Table 4 - Principal data of residential reference buildings – large apartment block


9

The models for office buildings correspond to the following two types of building, characterised by

a different distribution of internal space, different measurements and different ratios between

transparent and opaque surfaces.

- 2-floor office building;

- 5-floor office building.

ID of building


CL

IMA

TIC

ZO

NE


No of units


[m2] [m3] [m

2] [m

2] [m-1] [m] [-] [-] [W/m2 K] [W/m2 K] [W/m2 K] [W/m2 K]

UFF_E1

363 1339 804 99.8 0.60 2.77 2 -

1.53 4.00 1.20 0.36 B

see original

for picture

1.53 2.60 1.20 0.36 E

UFF_E2

2007 7200 2340 488 0.32 2.69 5 -

0.50 3.20 0.85 0.25 B

see original for picture 0.50 3.20 0.85 0.25 E

UFF_N0

1536 6077 2125 434 0.35 2.70 4 -

B

see original for picture

E

Table 5 - Principal data of office reference buildings

The new model introduced is an existing school building, dating back to the 1940s, spread over four

floors above ground with a non-heated basement. The outer perimeter walls are solid clay-brick

cavity walls, the upper floor of the main building is in non-insulated clay-cement, and is directly

under the unheated loft; the ground floor flooring is partly over the ground and partly over the

unheated basement; there are two types of window: timber frame with single glazing, original and

in disrepair, and aluminium frame with double glazing.

ID of building


CL

IMA

TIC

Z

ON

E


No of units



10

[m2] [m3] [m

2] [m

2] [m-1] [m] [-] [-] [W/m2 K] [W/m2 K] [W/m2 K] [W/m2 K]

SCU_E1

8935 47223 11549 1399 0.24 3.70 4 -

1.41 4.25 1.65 1.26 B

see original

for picture

1.41 4.25 1.65 1.26 E

Table 6 - Principal data of school reference building

4. ENERGY EFFICIENCY MEASURES

As in the 2013 exercise, we will assess the interaction between different measures (e.g. envelope

insulation affecting the power and dimensions of installations), combining them in packages and/or

variants in order to create synergies to achieve better results (in terms of costs and energy

performance) than can be achieved with single measures.

The energy retrofitting measures considered in the comparative methodology have been divided

into different categories, depending on the type of building analysed: existing residential buildings,

new residential buildings, existing office buildings, new office buildings, existing school building.

In each category, for each measure we use a scale of values on several levels (2 to 5); the first one

represents the present situation for existing buildings, which is inferior and not in line with current

legal requirements for new buildings (e.g. non-insulated envelope), and the last level always

considers solutions for improvement. The intermediate levels are set incrementally to reflect the

increasing performance of the parameters being assessed.

Seventeen (17) energy efficiency measures will be assessed. They can be grouped into three

subgroups:

1. opaque and transparent building envelope;

2. heating, cooling, DHW, ventilation and lighting installations;

3. renewable energy installations.

No ENERGY EFFICIENCY MEASURES PARAMETER Max No

of levels

OP

AQ

UE

EN

VE

LO

PE

1

Thermal insulation of:

• vertical covering on the outside

cladding

see original for

pictures

Uwall

[W/m2 K]

5

2 alternatively in cavity (if present)

3 • horizontal upper covering (top floor) Uroof/uf

[W/m2 K]

5

4 • horizontal lower covering (first floor) Ulf

[W/m2 K]

5


11

TR

AN

SP

AR

EN

T

EN

VE

LO

PE

5 Installation of high energy performance door and

window frames

Uw

[W/m2 K]

5

6 Installation of external solar shading τsol

[-] 2

Table 7 – Energy efficiency measures of envelope


of levels

HE

AT

ING

, C

OO

LIN

G,

DH

W,

VE

NT

ILA

TIO

N A

ND

LIG

HT

ING

7 Installation of air-to-air (multi-split) cooling device see original for

pictures

EER

[-] 3

8 Installation of thermal energy generator for heating *

ηH,gn/COP

[-] 3

9 Installation of thermal energy generator for DHW * ηW,gn/COP

[-] 3

10 Installation of combined thermal energy generator

for heating and DHW *

ηH+W,gn/COP

[-] 3

11 Installation of heat pump for heating, cooling and

DHW (with fan coil units)

COP

[-] 3

EER

[-]

12 Installation of high-precision control system for

heating and cooling

ηrg

[-] 3

13 Heat recovery on ventilation ηhru [-]

4

14 Installation of high-efficiency lighting equipment PN

[W/m2]

4

15 Installation of a lighting

control system

Occupancy dependency factor Fo

[-]

4 Daylight dependency factor FD

[-]

Constant illuminance factor FC

[-]

Table 8 – Energy efficiency measures for heating, cooling, ventilation, domestic hot water and

lighting installations


12


of levels

RE

NE

WA

BL

E

SO

UR

CE

S 16 Installation of solar collectors (only for DHW)

see original for

pictures Acoll

[m2]

3

17 Installation of photovoltaic panels Wp

[kWp] 4

Table 9 - Energy efficiency measures relating to renewable energy installations

5. DESCRIPTION OF MODEL FOR CALCULATING ENERGY PERFORMANCE

The objective of the calculation procedure is to determine the annual overall energy requirement in

terms of primary energy, which includes the energy requirement for heating, cooling, ventilation,

domestic hot water and lighting.

The procedure comprises the following phases:

1) Calculation of the building’s net thermal energy needs to satisfy the users’ requirements. For

example, in winter the energy requirement is calculated as dispersion of thermal energy for

transmission through the envelope and for ventilation minus internal gains (from devices,

lighting systems and occupancy) and ‘natural’ energy gains (passive solar heating);

2) subtraction of thermal energy generated from renewable sources and used on site (for example,

from solar collectors);

3) calculation of energy needs for each end use (space heating and cooling, hot water, lighting,

ventilation) and for each energy carrier (electricity, fuels), taking account of the characteristics

of generation, distribution, emissions and control systems;

4) subtraction of electricity generated from renewable sources and used on site (for example,

from photovoltaic panels);

5) calculation of energy delivered to the building for each energy carrier;

6) calculation of primary energy delivered, using national conversion factors (Ministerial Decree

of 26 June 2015);

At national level the energy needs of buildings were calculated using the semi-stationary method

based on standard UNI/TS 11300. Compared to the previous application of the comparative

methodology in 2013, the following analysis was conducted with the updated package now in force

based on the UNI/TS 11300 series. The following parts of the series were used:


13

o UNI/TS 11300-1:2014 ‘Energy performance of buildings – Part 1: Evaluation of energy

need for space heating and cooling’

o UNI/TS 11300-2:2014 ‘Energy performance of buildings – Part 2: Evaluation of primary

energy need and of system efficiencies for space heating and domestic hot water production,

for ventilation and lighting in non-residential buildings’

o UNI/TS 11300-3:2010 ‘Energy performance of buildings – Part 3: Evaluation of primary

energy need and of system efficiencies for space cooling’

o UNI/TS 11300-4:2016 ‘Energy performance of buildings – Part 4: Renewable energy and

other generation systems for space heating and domestic hot water production’

o UNI/TS 11300-5:2016 ‘Energy performance of buildings – Part 5: Calculation of primary

energy and the share of energy from renewable sources’

In addition, for calculation of the energy need for lighting in non-residential buildings, reference

was made to standard UNI EN 15193:2008 ‘Energy performance of buildings – Energy

requirements for lighting’.

Finally, it should be remembered that evaluation of the energy performance of buildings, according

to UNI/TS 11300, is a calculation based on the data for the components of a building, as assembled,

under certain conditions such as climate, use and operation. This choice does not present problems

for assessment of the design of new buildings, while in the case of existing buildings the lack of

data on components and construction methods (which in some cases it is not possible or at least too

costly to check) raises difficulties in assessing and classifying the energy status of buildings.

UNI/TS 11300, in consideration of these difficulties, provides reference data for existing buildings

for cases where adequate information is not available.

6. ASSESSMENT OF COSTS OF ENERGY EFFICIENCY MEASURES

Costs for measures to improve the envelope

The costs associated with the energy retrofitting of the building envelope will be assessed by

considering their main elements, such as:

• opaque elements (vertical walls, floors, roofs);

• transparent elements (windows and doors, frames);

• shading systems (external fixed screens, mobile screens, etc.);

and establishing a parametric index representative of the overall cost associated with possible

improvements or replacement of the component.

The costs will be obtained from national price lists, including the type of material used, installation,

compliance with building specifications, and any associated construction works closely linked to

carrying out the improvement measure.

Costs for measures to improve installations

The overall costs associated with the various technical building solutions adopted for the heating,

ventilation, and air conditioning (HVAC) of the buildings studied, and those for energy production

from renewable sources (PV and SOL), are not easy to evaluate since they are influenced by

multiple parameters.


14

The wide range of models and technologies on the market make the costs parameter highly variable.

It is also possible that installations that are similar in terms of energy performance have

significantly different costs in that they are different in other respects, such as technologies used,

materials, acoustic classification, control devices, trademarks or other components.

As we did for the previous report in 2013, for the purposes of the calculation method it will be

necessary to organise the various installations using ‘standard’ configurations in order to identify

the most common types of installation in the buildings studied.

For each installation, the overall cost will be established by associating an average market cost with

the main subsystems: generation, type of control, emission system and main electrical/hydraulic

components.

The various types of generator will be identified by taking account of the heating requirements of

the various buildings being studied, both new and existing. Then these will be linked to the types of

terminal and control compatible with the technologies under consideration.

The costs for installations run on renewables will be assessed by looking at, for photovoltaic

installations, the installed capacity with reference to a percentage of the roof surface area available,

and for thermal solar installations, a surface area calculated for daily water needs in line with the

intended use.

7. FRAMEWORK OF CALCULATION PROCEDURE

The calculation will follow the same procedure as for the previous study: starting from the energy

requirement for the reference buildings, we proceed, by way of an iterative calculation, to the

package of measures that will guarantee the cost-optimal level for that specific building category.

For the optimisation procedure, an optimisation macro was developed which interfaces with the

spread sheets for calculating the energy requirement and the overall cost.

Figure 1 charts the optimisation procedure used.


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Key:

EEM LEVELS

EEM COST DATABASE

EEM levels

cost

EEM levels cost

OVERALL

COST TOOL

AUXILIARY

SPREADSHE

ET

EEM levels parameters

OPTIMISATION PROCEDURE

TOOL

OVERALL COST

EEM OPTIMAL LEVELS

EEM LEVELS

building

parameters

EEM LEVELS

installation

parameters

EP EEM

LEVELS

installation parameters

heat pump

district heating UNI/TS 11300-5 biomass EH,W,del

UNI/TS

11300-1 QH,nd UNI/TS 11300-2

UNI/TS

11300-4

solar thermal

photovoltaic EPV

QC,nd Appendix D EV,del UNI/TS 11300-2

UNI/TS

11300-3 UNI/TS 15193-1

EL,del

EC,del

Figure 1 - Optimisation procedure

The optimisation method considers discrete energy efficiency options (for example, different levels

of installed peak capacity of photovoltaic installations), applied one at a time to obtain a new partial

‘optimised building’ for each calculation step.

The procedure makes it possible to establish a succession of configurations (packages of measures)

which constitute ‘partial optimums’. In order to move from a partial optimum to the successive one,

all the parameters that characterise the levels of each energy efficiency measure are modified.

Among all the configurations analysed, the successive partial optimum is that which allows for the

greatest reduction of overall cost.

Example:

EEM Levels

1 2 3 4 5

No EEM Parameters UM Value of parameters

1 Thermal insulation of EXTERNAL WALLS with cladding

Uw [Wm-2

K-1

] 0.3 0.26 0.20 0.10

2 Thermal insulation of EXTERNAL WALLS in cavity

Uw,c [Wm-2

K-1

]

3 Thermal insulation of UPPER FLOOR Ur [Wm-2

K-1

] 0.25 0.22 0.15 0.10

4 Thermal insulation of LOWER FLOOR Uf [Wm-2

K-1

] 0.30 0.26 0.20 0.10

5 Replacement of DOORS AND WINDOWS Uw [Wm-2

K-1

] 1.80 1.40 1.20 1.10


16

6 Installation of SOLAR SHADING (τ = 0,2) - - Fixed Mobile

7 Air-to-air COOLING DEVICE EER [-] 2.5 3.5

8 HEAT GENERATOR for HEATING (+ emission system)

ηgn,H/COP [-] 0.9 0.97 3

9 HEAT GENERATOR for DHW ηgn,W/COP [-] 0.85 0.9 2.5

10 COMBINED GENERATOR for HEATING

and DHW (+ emission system) ηgn/COP [-] 0.9 0.97 3

11 Reversible air-to-air heat pump (for

HEATING, COOLING and DHW)

COP [-] 3 4

EER [-] 2.5 3.5

12 SOLAR THERMAL DEVICE Asol [m2] 2

13 PHOTOVOLTAIC DEVICE PPV [kWp] 1

14 HEAT RECOVERY DEVICE (ventilation) ηhru [-]

15 CONTROL SYSTEM - - Space

16

LIGHTING SYSTEM PN [Wm

-2]

FO [-]

Lighting control system FC [-]

FD [-]

Table 10 – Example of identification of an EEM package for an optimised building

8. REPRESENTATION OF PROCESSING AND RESULTS

The processing and results will be shown as for the 2013 report.

For each of the 26 model buildings, alongside the optimisation trajectories represented by the

Pareto Front, four more graphics will be presented, described below and shown by way of example

in Figures 2-4.

1. Delivered energy by energy carrier/fuel for each of the energy services assessed (see

Figure 2);

2. Index of overall energy performance and for the individual energy service based on

primary energy with % breakdown of renewable and non-renewable energy share (see

Figure 3);

3. Energy produced from renewable sources on site, with breakdown by individual energy

service (see Figure 4);

4. Discounted costs by energy, operation and maintenance, initial investment (see

Figure 4).


17

By processing the results obtained by applying the method it will be possible to establish the

optimal solutions for the various categories of building and for the different scenarios predicted, and

it will then be possible to compare these values with existing legal requirements.

Ener

gy d

eliv

ered

[k

Wh

a]

Thousa

nds 9 Thermal energy (heat pump)

8 Electricity (photovoltaic)

7 Thermal solar

6

[see original]

District heating

5 Grid Electricity

4 Biomass

3 LPG

2 Gas oil

1 Natural gas

0

H C W V L

Figure2 - Energy delivered (Example of representation)


18

Figure 3 - Energy performance indices (Example of representation)

900 Operation and

maintenance

En

erg

y f

rom

ren

ewa

ble

sou

rces

on

sit

e [k

Wh

a]

800

see original

Surplus

Co

st [

€/m

2]

800

700 L 700

600 V 600

500 W 500 Initial

investment 400 C 400

300 H 300

200

200

Energy 100 100

Photovoltaic Thermal

solar 0 Overall cost

Figure 4 - Energy from renewable sources and discounted costs (Examples of representation)

Documents

UPDATE OF THE APPLICATION IN ITALY OF THE ......Update of the application in Italy of the method for calculating cost-optimal levels for minimum energy performance requirements (Directive