MANUAL FOR STATISTICS ON ENERGY
CONSUMPTION IN HOUSEHOLDS
- MESH PROJECT -
Report 5. Standardization of
Methodologies
AUGUST 2012
2012
STANDARDIZATION OF METHODOLOGIES
ÍNDEX
1.
STANDARDIZATION ......................................................................................... 4
1.1.
INTRODUCTION ........................................................................................... 4
1.2.
GENERAL ISSUES .......................................................................................... 5
2.
INFORMATION SOURCE: SURVEY ................................................................ 11
2.1.
ESTABLISHMENT OF PURPOSES ................................................................. 11
2.2.
ORGANIZATION OF THE FIELDWORK ...................................................... 12
2.3.
INCIDENCES AND TREATMENT ................................................................. 12
2.4.
SAMPLE DESIGN ........................................................................................ 13
2.4.1.
Sampling .......................................................................................................................................... 13
2.4.2.
Size of the sample........................................................................................................................... 13
2.4.3.
Sampling error ................................................................................................................................. 14
2.5.
QUESTIONNAIRE DESIGN .......................................................................... 14
2.6.
DATA COLLECTION ................................................................................... 16
2.7.
DATA CLEANING ....................................................................................... 16
2.8.
VALIDATION ............................................................................................... 16
2.9.
EXTRAPOLATION........................................................................................ 17
3.
STATISTICAL METHODS: MODELLING .......................................................... 18
3.1.
OBJECTIVE.................................................................................................. 18
3.2.
DATA SOURCES (INPUTS) .......................................................................... 19
3.3.
METHODOLOGY ........................................................................................ 19
3.4.
CORRECTIONS, ADJUSTMENTS AND REVISIONS.................................... 20
3.5.
PUBLISHING ................................................................................................ 20
4.
STATISTICAL METHODS: IN SITU MEASUREMENT ......................................... 22
4.1.
PURPOSE..................................................................................................... 22
4.2.
SAMPLE DESIGN ........................................................................................ 22
2
4.3.
METHODOLOGICAL DEVELOPMENT ...................................................... 23
4.4.
CLEANING AND CONTROL ...................................................................... 24
4.5.
EXTRAPOLATION........................................................................................ 25
ANNEX I: SAMPLE QUESTIONNAIRE....................................................................... 26
ANNEX II: “IN SITU MEASUREMENTS” ..................................................................... 42
STANDARDIZATION OF METHODOLOGIES
1. STANDARDIZATION
1.1.
INTRODUCTION
Once users’ needs have been established and after having elaborated the Global
Inventory and described the good practices in the field of energy statistics detected in the
Member States, this report aims at delivering options for the statistical methodology that
countries can implement, from their various starting points, in order to build up full and
comparable data on energy use in the residential sector.
As it is stated in MESH project:
It is likely that all EU Member States will fall into one of the following categories with regards
to statistics on energy in the residential sector:
1. States that do not have information about residential energy consumption, not even at
an aggregated level.
2. States that have energy consumption information about the residential sector at an
aggregated level, but not in detail.
3. States that have aggregated and detailed information about energy consumptions in
the residential sector.
According to these categories, homogeneous groups of countries have been established
in Report 1, and appropriate recommendations for each of these groups will be made in
Report 6. These countries have been classified into five groups instead of three, so as to
differentiate in more detail the needs of each Member State. The classification into the
different groups has been made regarding the coverage of the requirements of TF2008,
because other different recommendations for grouping the countries have been
considered but they have resulted in more heterogeneous groups than regarding the
previously mentioned coverage rate.
In this report, once homogeneous groups of countries have been fixed with the aim of
specifying recommendations according to their needs, the purpose consists in establishing
the methodology that all the countries should apply in order to achieve the desired
standardization and consequently allow the comparability of statistics on energy
consumption in the residential sector among all the EU countries.
What we understand by “Standardized Methodology”?
“Use of a common normalized system of methodological components: harmonised
concepts and definitions; statistic units; classifications; nomenclatures and codes;
standardized models of questions and standard variables …..Which make it possible the
comparison, integration and analyses of data and results?” 1
This definition has been used in a meeting of the MESH project, according to the literature available on the
subject.
1
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STANDARDIZATION OF METHODOLOGIES
Standardization plays an important role concerning the quality of the statistical information
produced, as it serves as a tool for diagnosing problems, performing measurements and
establishing quality standards, which define some acceptable quality intervals and allow
finding the causes of the failures in the statistical processes. The standardization both of
concepts (it will be made in Report 7) and statistical information is essential to the
statistical integration and harmonization, because quality statistics may be achieved as a
result of having standards of concepts, norms, methodologies and processes. Besides,
standardization harmonizes results in order to guarantee their coherence, comparability
and integration.
Within the framework of the MESH Project, after the analysis of the situation about statistics
on energy consumption in households in all member countries and the evaluation of best
practices both geographically and according to statistical methods, the final choice of
the best and most appropriate methodologies for measuring energy consumption in the
residential sector has been selected which is based on the implementation of an “ad hoc”
survey, in situ measurements, and exploitation of a model for calculating energy
consumption by end uses which uses as inputs some of the data achieved by means of
the survey and the in situ measurements and at the same time serves for checking the
results obtained from these information sources.
In order to establish the standardization of the selected methodology, in the next section
some general questions which have been taken into account are described.
In the following chapters of this report each of the selected statistical methods and the
guidelines and norms to be followed are explained in more detail.
GENERAL ISSUES
1.2.
Next, the main features of a standardization process are highlighted, taking as reference
the following reports: “Standard for statistical processes 2001” by Peter Van Nederpelt, CBS
Statistics
Netherlands;
(“Methodology
for
“Metodología
standardization
of
para
la
estandarización
concepts”),
National
de
Bureau
Conceptos”
of
Statistics,
Department of Regulation, Planning, Standardization and Normalization
-DIRPEN-
(September 2009); “Estandarización de documentos metodológicos de las operaciones
estadísticas” (“Standardization of methodological documents of statistical operations”),
Strategy for Strengthening Territorial Statistical (December 2011).
Objectives
These objectives are:
-
Contributing to the publication of reliable and coherent statistical information that
responds to the needs of the Member States of the EU.
-
Fulfilling the values of reliability, relevance, coherence and topicality. In addition
with the requirements of privacy and confidentiality.
In adition, 3 strategic objectives will be considered:
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STANDARDIZATION OF METHODOLOGIES
-
Conceptual framework which provide a common basis to consolidate the statistic
information on energy statistics in the household sector
-
Concepts and definitions, statistical units, variables, and classifications.
-
Coherent use of data acquisition and processing methods in order to produce
statistical data
Context
The Standards are deduced from a list of existing frameworks. These frameworks are
described below:
1.- European Statistics Code of Practice: All relevant principles and indicators of the Code
of Practice (Eurostat, 2011) are mapped to the Standard.
2.- Handbook of Recommended Practices for Questionnaire Development and Testing in
the European Statistical System (Eurostat, 2006).
3.- International Recommendations for Energy Statistics (IRES). Draft version prepared by
the United Nations Statistics Division, 2011.
4.-Other standards
Initial inventory of
concepts/ methods.. obtained
from glossaries, NSIs, etc. of
the countries considered in the
geographic coverage
Review,
adjustment
and depuration
Selection of a
glossary of
concepts/ methods
Criteria to
standardize
concepts/ methods
Standardized
methodology
(1) Relevant concepts/ methods for the design and (1) Accordance with international official
guidelines/ recommendationsor theory;
development of the statistical operations;
(2) Other concepts/ methods
(2) Concepts/ methods of interest to consider
Objects
In the Standard a set of objects that relate to statistical processes is discussed. These
objects are:
1. Methodology.
2. Agreements with external data suppliers.
3. Data sources (input).
4. Provision of data sources
5. Accuracy of statistical data
6. Meta data.
7. Processes.
8. Reporting burden.
9. Output specifications for external customers.
10. Quality documentation and reports.
11. Revisions.
12. Statistical concepts.
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STANDARDIZATION OF METHODOLOGIES
13. Statistical data.
14. Statistical output.
Next, each of the objects concerning the standardization is described.
1)
Methodology
Special attention must be paid to the soundness of the methodology. A
methodology must be reviewed regularly.
2)
Agreements with external data suppliers.
It must be an agreement with every external data supplier. An agreement is a legal
obligation (contract or law).
3) Data sources (input).
A data source is a data set that is an input for a statistical process.
A data set can play different roles:
-
As data for compiling the statistics.
-
As sample framework.
-
As input for determining weights in order to relate the sample units to the
population
A data source can be either a micro data set or an aggregate.
In the case of micro data sets the following objects and associated characteristics
can be distinguished:
-
Dataset: completeness, stability and timeliness/punctuality.
-
Unit: completeness, confidentiality, correctness, selectivity, stability, timeliness and
uniqueness.
-
Data (items): coherence, completeness, confidentiality, correctness, selectivity,
stability, timeliness and uniqueness.
Regarding data sources the following characteristics are distinguished:
1. Completeness of units (in case of registers)
2. Correctness of units (in case of registers)
3. Completeness of data
4. Correctness of data
5. Coherence of data items with the statistical concept of the output
6. Accuracy (in case of aggregates)
4)
Provision of data sources
A data source can be provided by internal as well as external suppliers. Punctuality
of input provision and Continuity of provision of data sources are main relevant
characteristics of provision of data.
5) Accuracy of statistical data
Accuracy of statistical data regards mainly aggregates rather than micro data.
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STANDARDIZATION OF METHODOLOGIES
The accuracy of data depends on:
1. The implementation of the different steps in the statistical process and
2. The data sources (input) (object 3), afore described.
In the statistical process, some causes of problems with accuracy of data can
occur in the following steps:
-
Sampling
-
Data collection
-
RaisingAchieving response
-
Editing
-
Imputation
-
Outlier detection and processing
-
Coding
-
Transforming
-
Linking
-
Weighting, and raising to the population
-
Correcting
-
Publishing
-
Logistic operations
6) Meta data.
Conceptual Meta data are data (information) about data. This is:
-
The description of the statistical unit.
-
The description of the population characteristics of these units.
-
The names and definitions of the data items.
-
The referential period of time, as well as the referential period of time concerning
the population.
7) Processes.
The following characteristics of processes are distinguished:
1. Efficiency
2. Completeness
Efficiency of implemented processes: Efficiency of processes means that the
required quality is provided with minimal costs.
Completeness: some additional processes are in place for monitoring and
validating source data, interim results and statistical output. These processes are in
place to evaluate and monitor the quality of output, that is, in order to deal with
quality considerations, and they make the whole statistical process complete.
8) Reporting burden.
Reporting burden is the effort it takes for respondents to answer the questions.
The following characteristics of reporting/response burden can be distinguished.
1. Level
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STANDARDIZATION OF METHODOLOGIES
2. Spreading
3. Necessity
9) Output specifications for external customers
In the output specifications it is documented which products will be delivered to
external users and what the required quality of these products is. It regards ‘ex
ante’ specifications, not explanations afterwards (‘ex post’).
10) Quality document and reports.
The quality document is compiled within the framework for ensuring the quality of
the statistical processes and the pertinent regulation of governments concerning
information security.
Quality reports are used for two purposes:
-
Testing whether the intended quality is achieved, and subsequently managing the
process. Extra Measures can be considered if the quality is insufficient.
-
Giving account on the quality of the products.
The following characteristics of quality reports are distinguished:
1. Availability
2. Compliance with Eurostat regulations
3. Compliance with agreements with other users
4. Punctuality of provision
11) Corrections, adjustments and revisions.
The following characteristics of corrections, adjustments and revisions are
distinguished:
1. Compliance with guidelines
2. Existence of analysis
12) Statistical concept.
It is the description of the statistical unit (object type), the delineation of the
population, subpopulations (classifications) and the data items including the
definitions and the referential period (concerning the population as well) of the
output.
Characteristics of the statistical concept are:
1. Relevance: It is taken into account which users need the statistical information, as
all statistics must be published.
2. Coherence with other statistics.
13) Statistical data.
Statistical data are the values of the data items.
Characteristics of statistical data are:
1. Accuracy. A separate chapter is dedicated to this dimension.
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STANDARDIZATION OF METHODOLOGIES
2. Comparability
3. Consistency
14) Statistical output
Statistical output means statistical presentation in various forms such as tables,
including explanations, graphs, diagrams, charts, or animations.
Characteristics of statistical output are:
1. Clarity
2. Accessibility
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STANDARDIZATION OF METHODOLOGIES
2. INFORMATION SOURCE: SURVEY
After a careful analysis of the situation of all the countries subject of study within the
framework of the MESH Project, it has been concluded that the first primary information
source to be exploited must be a survey.
The goodness of the quantitative methods for collecting information consists in enabling:
•Standardization of information (organized questionnaire)
•Simplicity regarding the compilation of information
•Quickness of tabulation
•Means of analyzing a great amount of individuals
As it has been explained in the first chapter, the standard methodology proposed to be
implemented in every EU country is based, firstly, on the production of an ad-hoc survey.
The ad-hoc surveys involve certain advantages like the fact that an elevated response
rate can be achieved, a direct reply from the respondent is given to the interviewer, there
is not influence from other people, supporting equipment can be used and additional
data may be collected annexed to the questionnaire. It must be pointed out the fact that
they imply a higher cost, especially if they are face-to-face.
The main steps that must be taken in order to develop a survey are going to be revealed
below: establishment of purposes, organization of the fieldwork, sampling, questionnaire
design, data collection, data cleaning and processing, validation and extrapolation.
2.1.
ESTABLISHMENT OF PURPOSES
The purpose of the face-to-face survey is to obtain:
 Dwelling characteristics, like dwelling type, age of the building, penetration of
energy efficiency technologies…;
 Household characteristics, like the number of members of the households, income,
household equipment…;
 Data on energy consumption by commodity type and by end-use;
 Extra information about the behaviour regarding energy consumption in the
household;
Other additional purposes are:
 Serving as a basis for reconciliation with other data
 Obtaining information that can be compared among countries.
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STANDARDIZATION OF METHODOLOGIES
2.2.
ORGANIZATION OF THE FIELDWORK
The survey must have a two-yearly frequency and has to be carried out in a particular
period of the year (for instance, during the second half of the year). A large enough
period of time must be allowed in order to execute the fieldwork, since the absent and
inaccessible individuals must be taken into consideration.
The execution of the survey must be communicated to every selected household. A
specific appointment should also be determined.
The survey has to be carried out by means of a computer assisted personal interview
(CAPI). The interviewers ought not to use paper questionnaires: they should utilize a laptop
in which the questionnaires are installed, so that the surveys may be conducted with the
help of computing.
2.3.
INCIDENCES AND TREATMENT
During the fieldwork some difficulties or incidences may occur, so that a particular solution
related to each one must be provided.
There may be several types of incidences regarding households:
- Inaccessible dwellings
- Untraceable dwellings
- Dwelling intended for other purposes
- Empty dwelling
- Duplicated dwelling due to an error during the selection process
Thus, a complementary set of dwellings should be established in case one of the above
inconveniences takes place.
Besides, the respondent may also cause some kind of difficulty:
- Total refusal to respond
- Partial refusal to respond
- Total absence
- Absence of the selected respondent
- Incapacity to respond
In these cases, a dwelling from the complementary list should replace the original one. It
must be emphasized the fact that a survey is understood to be complete if, at least, 70%80% of the questions have been answered.
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STANDARDIZATION OF METHODOLOGIES
2.4.
2.4.1.
SAMPLE DESIGN
Sampling
During the determination of the sampling frame, a few essential considerations must be
taken into account in order to achieve more accurate and useful data.
It seems required to considerate the differences that households may show during the
sample design due to the type of region, tenure or dwelling.
Thereby, it is crucial to develop a stratification of the sample according to climate zones:
the habits of consumption may be different depending on the climate region where the
dwelling is placed.
Those countries which show an important presence of rural areas ought to consider the
level of urbanity when it comes to carry out the sampling process: differences between
rural and urban areas are expected to appear. This distinction plays a very important role
when it comes to analyzing the energy consumption by energy source: in urban zones, the
most of energy consumption derives from electricity or natural gas (consumption of other
traditional energy sources is residual or isolated); whereas in rural zones, traditional energy
sources like wood are more commonly consumed.
Besides, the differences generated by the tenure regime (ownership or tenancy) have to
be revealed. This distinction comes from the fact that the owner tends to have a greater
knowledge of the equipment characteristics and the energy consumption than the
tenant. In case the respondent of the survey is a tenant, contrasts using information
provided by landlords or property administrators could be very useful.
Therefore, the realization of all these factors related to sampling can involve the
organization of the process in two different phases: the first one including the
establishment of sub-samples concerning climate and level of urbanity; the second one
differentiating dwellings according to the tenure regime. Once all the sub-samples have
been established, individuals to be interviewed will be selected by means of a simple
random sampling in order to minimize the potential bias that may appear during the
collection process.
2.4.2.
Size of the sample
The number of households that will be included in each sub-sample will depend on the size
of each aforementioned sub-sample. It is known that, for population sizes larger than
100.000 individuals, variations over this number do not involve important changes
regarding sample size.
This sampling system based on stratifications reduces the variance and costs. Additionally,
it guarantees a lower standard error and a more representative sample.
Furthermore, there are other factors that can be relevant when it comes to designing the
sample size. For example, those dwelling whose use aims at some kind of economic
activity (not related to the residential sector) must not be taken into account.
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STANDARDIZATION OF METHODOLOGIES
2.4.3.
Sampling error
The sampling error can be estimated, and this enables the establishment of a numerical
interval for the point estimates. Consequently, it can be stated with a certain degree of
confidence, measured in terms of probability, that the true value of the estimated
characteristic falls within the confidence interval. The confidence interval commonly used
includes the estimation ±1.96 times the sampling error. This interval conveys a confidence
of 95% that the true value of the estimated variable is included within its limits.
2.5.
QUESTIONNAIRE DESIGN
Questionnaires2 constitute the basis of every survey-based statistical measurement. They
are by far the most important measurement instruments statisticians use to grasp the
phenomena to be evaluated. Errors due to an insufficient questionnaire can hardly be
compensated at later stages of the data collection process. Therefore, having systematic
questionnaire design and testing procedures in place is vital for data quality, particularly
for a minimization of the measurement error. Consequently the questionnaire should ask
relevant questions and permit data to be collected efficiently and with minimum error,
while facilitating the coding and capture of data and minimizing the amount of editing
and imputation that is required.
The process of questionnaire design includes various successive steps: the development of
a conceptual framework, writing and sequencing the questions, making proper use of
visual design elements as well as implementing electronic questionnaires technically. In
order to achieve cross-national comparability among European or international surveys,
two further tasks are necessary. The translations of the questions or questionnaires have to
be functionally equivalent, i.e. the respondents in different countries must have the same
understanding of the questions. The demographic as well as socio-economic variables
have to be harmonized through commonly accepted instruments.
The questionnaire in the first instance is a measurement instrument. Its main purpose is to
introduce the user’s information demand into a format which allows a statistical
measurement. The concepts of “reality” must be operationally defined in a way that
enables the subject-matter specialists and the users to carry out the necessary analyses,
that the questionnaire designer can implement into the questionnaire, and that the
respondents can understand and answer properly. Hence, the design of questionnaires
must primarily take into account the (statistical)/information requirements of data users. In
order to provide a valid and reliable measurement, the wording, structure and layout must
make allowance for the nature and characteristics of the respondent population. Further
requirements include the organizational setting of the statistical office and the technical
requirements for data processing. Additionally, the questionnaire should impose the lowest
possible response burden and remain both respondent and interviewer friendly.
As it is defined in the report: “Handbook of Recommended Practices for Questionnaire Development and
Testing in the European Statistical System”.
2
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STANDARDIZATION OF METHODOLOGIES
The following recommendations support an efficient implementation of the questionnaire
design process:

In order to develop the questionnaire regarding energy consumption in
households, a review of the documentation available is needed, especially
concerning standardization of concepts (so that each one coincides with the
information revealed by other countries). Several definitions and standardizations
of concepts have been executed throughout these studies (Report 7).

In order to achieve cross-national comparability among European surveys, the
questionnaires used in different countries have to be functionally equivalent, i.e.
must actually measure the same concepts in different cultures and languages.
Thus, every concept must be coincident in every country, so that comparisons
among different EU Member States regarding energy consumption in households
can be made.

Before starting to draft the questionnaire, the survey objectives should be specified
in co-operation with important users and stakeholders. Thereby, when it comes to
designing questionnaire related to energy consumption in the residential sector,
the main purpose has to be taken into consideration, which is the achievement of
a reliable estimate of the final energy consumption of a typical household by end
use category (space heating, water heating, space cooling, cooking, electrical
appliances and lighting).

Subsequently, the objectives need to be translated into observable variables. This
process plays a momentous role: some concepts may turn out to be quite difficult
due to their technical aspect, so that the questionnaire must be very clear in order
to make the comprehension of the respondent easy. In addition, the concepts and
indicators the users are seeking must be compatible with those the respondents
have in mind.

Once the objectives and concepts are defined, a concrete list of variables should
be laid down specifying the expected output of the survey. The variables and
values list must be regarded as a simple list of variable names and values as well as
their corresponding definitions. It is recommended to draw a distinction between
background variables (e.g. demographic variables), variables related to survey
concepts, and technical variables (e.g. required for weighting).

All data collection instruments in these statistical processes have to provide valid
and reliable results, i.e.: make sure that survey questions are understood and
answered correctly by the respondents, and can be administered properly by
interviewers…., etc.
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STANDARDIZATION OF METHODOLOGIES
2.6.
DATA COLLECTION
Before the data collection takes place, the questionnaires have to be tested in a
systematic way.
Questionnaire testing is critical for identifying problems for both respondents and
interviewers. In order to get a sound understanding of the response process, to identify
problems about the questions and to suggest adequate improvements, the use of a
combination of questionnaire testing methods is indispensable.
Once the questionnaire has been designed and tested, it has to be implemented so that
the data collection process may take place. The selection of an appropriate data
collection mode must take into account the number, the contents and the scope of the
survey variables. The Computer Assisted Personal Interviewing (CAPI) seems to be the most
accurate method to collect data on energy consumption in households. This choice
derives from the fact that there are a few concepts of a high technical level that, if they
are not understood by the respondent, can be explained by the interviewer. According to
this, the interviewer staff should take specific lessons in order to become familiar with the
questionnaire and the particular terminology and concepts.
Additionally, electronic questionnaires are thought to make work easier. They enable to
detect and reconcile inconsistencies already during the interview. The electronic
questionnaire must be designed in such a way as to solve the greatest number of
inconsistencies while paying attention to the fluency of the interview and not frustrating
the respondent. The error management should make the interviewer understand sooner
what kind of error happened and which questions were involved in it.
2.7.
DATA CLEANING
Once the data have been compiled, a cleaning process must be carried out to detect
non response rates and causes, response distributions, edit failures…..
In order to reduce errors and inconsistencies to a minimum before the stage of data entry,
all completed questionnaires must be thoroughly checked and corrected for any
deficiencies or logical inconsistencies by the interviewers’ supervisors. In the case of
unusual answers or missing data, mechanisms aimed at correcting this kind of problems
must be established. It seems required to contact again the respondents that have shown
difficulties, so that requirements related to completeness of information may be fulfilled.
2.8.
VALIDATION
Despite the fact that mistakes made during the collection process have been cleaned, it
seems appropriate to reconcile and validate the resultant data by means of other
different sources. There are a few sources that can be utterly useful in order to determine if
the obtained data can be considered meaningful.
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STANDARDIZATION OF METHODOLOGIES
Data validation can be developed in different phases according to the different types of
blocks: features of dwellings and households, household equipment, or energy
consumption data by energy source or by end-uses.
Validation process can be carried out through:
1) Supplementary adjustment: used when some given variable has been reported by
some of the operations carried out but not by others. In this case, information
available can be completed by means of those sources that provide the
information.
2) Inter-operational adjustment: this correction must be executed when the two
sources used for validating provide very different data. There may be two different
situations regarding this issue:
a)
The variables provided by the different sources differ within an established
interval. The weighted average enables the adjustment of the sources.
b)
Only one of the sources differs from the rest, exceeding the established
interval. The adjustment is made by means of the weighted averages from
those sources which provide data included in the referred established
interval.
2.9.
EXTRAPOLATION
Once data obtained through the questionnaire have been cleaned, completed and
contrasted with other statistical sources, the results have to be extrapolated to the
national level. Generally, it seems required to use a confidence level of 95% in each subsample. These confidence intervals are indispensible when extrapolation results have to be
compared with results from other data sources, for instance with the consumption figures
published in the energy balances.
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STANDARDIZATION OF METHODOLOGIES
3. STATISTICAL METHODS: MODELLING
In order to define the essential factors that affect the execution of modelling processes, a
few standards are going to be explained, so that several steps which establish the
characteristics of a model related to energy consumption in households are going to be
enumerated. These standards concern objective, data source (inputs), methodology,
corrections, adjustments and revisions and publishing.
Before describing the key factors that define a modelling procedure, a very important
remark must be pointed out. Despite the fact that some specific sources have been taken
as a reference regarding survey and in situ measurements (surveys of Cyprus, Greece and
Spain have been considered as the best surveys, whereas the in situ measurement of
Spain has been considered to be the best one), it is very difficult to establish a standard
model: it depends on the characteristic, data and sources of each country. Nevertheless,
models developed by Slovenia and Finland could be, for the reasons exposed in Report 4,
a good standard that other countries should apply.
The general characteristics of a standard modelling procedure are explained below.
3.1.
OBJECTIVE
Firstly, a purpose for the modelling process has to be determined. Regarding statistics on
energy consumption in the residential sector, two crucial aims clearly dominate the design
of data models: the estimation of the final energy consumption by end-use and the
estimation of the final energy consumption by commodity type. The different end-uses
commonly accepted are space heating, cooking, water heating, space cooling, and
lighting and electrical appliances. On the other hand, the different sources of energy
taken into account by each country will depend on its own energy structure 3.
Consequently, an exhaustive definition of the different systems and appliances established
will be needed as well.
Thus, three requirements have to be fulfilled by means of the establishment of the main
purpose:

The output obtained has to be relevant, that is to say, it must be closely connected
or appropriate to the matter in question (energy consumption in households).

The output achieved has to be coherent, logical and consistent with other
statistics.

3
Efficacy and efficiency will be pursued from the very first moment.
An exhaustive list of the different energy commodities has been explained in Report 7.
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STANDARDIZATION OF METHODOLOGIES
3.2.
DATA SOURCES (INPUTS)
Secondly, independent variables have to be selected. These variables must be taken from
appropriate sources. The main inputs that can be used in order to achieve proper data
are: output obtained from ad-hoc or complementary surveys, census, household budget
survey, living conditions survey, housing and building stock, income distribution statistics, in
situ measurements, etc.
Some conditions related to objectivity and impartiality must be taken into consideration
when it comes to selecting the sources which will supply the data:

Statistics have to be compiled on an objective basis determined by statistical
considerations.

Choices of sources, and decisions about the dissemination of statistics, must be
informed by statistical considerations.

Errors discovered in published statistics have to be corrected at the earliest possible
date and publicized.

Data must be correct, complete and accurate.

The provision of input data has to be punctually carried out.
3.3.
METHODOLOGY
Furthermore, specifications about methodology have to be made. In order to obtain high
quality estimations about energy consumption in households, certain items must be
considered. The specific methodology (top-down or bottom-up) will depend on the traits
shown by the input sources. Besides, an important amount of characteristics might be
attained from compilations or administrative data: type of building, number of occupants
of the household, number of dwellings, area of the dwelling, age/type of the systems,
capacity of equipment, number of appliances, etc.
Additionally, other particular aspects may be utterly useful if a certain country shows
specificities regarding its geography, climate or population conditions. For instance,
factors of climate variability, population density or hours of sunlight can be very helpful in
order to undertake more precise estimations. Moreover, some assumptions may be
needed: for example, individual average energy consumption or energy required for a
certain end-use might be postulated by means of previous or complementary sources.
Adjustments in these assumptions will be needed too if errors are noticed during the
implementation of the model.
A few rules will determine the quality of the resulting output:

Data collection, data entry and coding must be routinely monitored and revised as
required.

Appropriate editing and imputation methods must be used and regularly reviewed,
revised or updated as required.

Revisions must follow standard, well-established and transparent procedures.
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STANDARDIZATION OF METHODOLOGIES

Efficiency and completeness must be pursued: resources must be effectively used,
measures to ensure efficient use of resources ought to be implemented, double
work must be avoided in the chain, work shall be used in an optimal way in order
to improve efficiency, the production activities must be done by staff with the right
qualifications, etc.

The overall methodological framework used shall follow European and other
international standards, guidelines, and good practices.

The staff that develops this methodology must show professional independency.
3.4.
CORRECTIONS, ADJUSTMENTS AND REVISIONS
Once the pertinent estimations have been carried out, a very important work regarding
reconciliation and validation must be executed. This step plays a crucial role: it enables
institutions to ensure the quality of the achieved output. There are several ways of
developing this process: on the one hand, comparisons can be made with information
given by suppliers, traders or importers; on the other hand, verifications may be executed
by means of data from national balances; additionally, some statistical methodologies like
the analysis of the variance or the breakdown of the trend data can be also used to
check the consistency of the output.
Consequently, it seems required to establish some considerations concerning reliability
and accuracy:

Revisions must be regularly analyzed in order to improve modelling processes.

Outputs (and even source data and intermediate results) have to be regularly
assessed and validated.

Statistics from the different sources and of different periodicity have to be
compared and reconciled.

Statistics must be internally coherent and consistent.
3.5.
PUBLISHING
One of the most important aspects of the implementation of a model process is the
publication of a methodological and results report. It must include a thorough description
of the methods that have been used, the details that have been considered in the design
of the model and the conclusions that have been reached at the end of the whole
procedure. Furthermore, a quality report should also be available in order to confirm that
the model meets the current quality regulations and agreements. By this manner, any
interested institution will be able to execute its own analysis. Moreover, these reports ought
to be written in English.
Some requirements regarding clarity, comparability, punctuality, transferability and
accessibility must be fulfilled:
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STANDARDIZATION OF METHODOLOGIES

Statistics and the corresponding data must be presented, and stored, in a form
that facilitates proper interpretation and meaningful comparisons.

Modern information and communication technology has to be used in order to
publish reports.

Timeliness must meet European and other international release standards.

Divergence from the dissemination time schedule has to be publicized in advance
and explained, and a new release date must be set.

Preliminary results of acceptable aggregate accuracy should be released when
considered useful.

Results must be comparable over a reasonable period of time.

Outcomes ought to be compiled on the basis of common standards with respect
to scope, definitions, units and classifications regarding the different surveys and
sources.
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STANDARDIZATION OF METHODOLOGIES
4. STATISTICAL METHODS: IN SITU MEASUREMENT
The last type of methodology that has been suggested in order to figure out the energy
consumption in households is the in situ measurement. Despite the fact that several
countries have carried out this kind of method, specific information has not been
provided. In like manner, Spanish documentation has been used to describe the
characteristics of the process.
Therefore, the following steps in order to implement this methodology properly are
presented next.
4.1.
PURPOSE
The purpose of the in situ measurement must be to obtain more accurate breakdown of
electricity use for various purposes and to reveal patterns of use.
Furthermore, it can be useful for validating national energy statistics and providing better
referential values on household electricity, to identify consumption, for identifying how
much of the total use is due to standby power consumption, for setting a basis for policy
measures intended to encourage the improvement of the efficiency of electricity use in
the domestic environment, for making consumers more aware of their own electricity
consumption, and for encouraging manufacturers to produce appliances with better
energy efficiency, among other issues.
4.2.
SAMPLE DESIGN
The way of developing the sample design will be similar to the one executed regarding
the ad-hoc survey. With a view to achieving a proper representativeness of the existing
climate zones and types of dwellings, it’s advisable to apply stratified methods or, in their
absence, to try to have an optimum representativeness of the average dwellings existing
in each population segment defined as the combination of climate zone and type of
dwelling.
The observation units are the principal dwellings, permanently occupied dwellings.
The sample size can be smaller than the one concerning the face-to-face survey on
energy consumption in households. Hence, it seems required to take the sampling work
related to the ad-hoc survey into consideration. Accordingly, a portion of the sample can
turn out to be very useful in order to carry out in situ measurements.
The measurements are normally referred to electricity consumption in dwellings, and
occasionally, to natural gas or/and other energy carriers, relevant for thermal
consumption. The development of methods aimed at the measurement of other energy
sources is recommended in order to perfect the statistics on energy consumption in the
residential sector.
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STANDARDIZATION OF METHODOLOGIES
METHODOLOGICAL DEVELOPMENT
4.3.
Once the sample has been determined, the fieldwork must be executed. This fieldwork is
executed by means of specific measurement equipment. The measurement equipment
must be duly calibrated, in accordance with the EC normative. The corresponding
calibration certificate should be mandatory.
The measures must be accompanied by a questionnaire addressed to the equipment, its
technical characteristics and pattern of use, differentiating between working days and
festivities. Additionally, a request on electricity and natural gas invoices corresponding to
the last 12 months must be made. This is important in order to have the hourly load curves
of the different equipment on the level of type of day (working day/festivities) in different
seasons, as well as on a yearly level.
The questionnaire must include the following questions:
 Region where the dwelling is located.
 Type of dwelling: single family house or multifamily house.
 Electricity consuming equipment in the household: number of equipment items by
type, power (kW) and, if possible, the power of standby.
 Habitual timetable of use of each equipment item.
 Type of lighting in each zone of the household, number and power (W) of the bulbs
and timetable of use.
 Electricity invoices data: contracted power, consumed energy (kWh) and the
period covered by the invoice.
In order to guarantee the access to the dwellings, it’s recommended to firstly proceed
with an informative letter sent by the promoter organization, explaining the interest of such
actuation. The collaboration of the households can be fostered by means of an offer of
free assessment on different areas related to energy use and saving. Secondly, with regard
to the measurement execution procedure, a proper training of the responsible team must
be assured.
According to the proposal that has been made regarding the questionnaire design, in situ
measurements must enable the attainment of detailed information about the main
electrical appliances
(equipment) in households and the differences arising from the
different end-uses. This will facilitate the comparisons and calibrations between data
obtained by means of the ad-hoc survey and the in situ measurements. Consequently, it is
crucial that the set of appliances/equipment taken into consideration by the in situ
measurements coincide with the ones studied through the survey. The following table
shows the main systems that can be analyzed by means of in situ measurements
according to their end-use. They are in keeping with the ones stipulated for the developed
questionnaire.
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STANDARDIZATION OF METHODOLOGIES
4.4.
CLEANING AND CONTROL
This measurement execution process must be accompanied by quality guarantee
procedures, on the level of field research, and on the level of preliminary data treatment.
In the first case, during the measurement execution all the information collected must be
validated in order to check that all the data have been taken in the right way. In addition,
an individual revision must be made. In this sense, individual revisions of up to 5% of the “in
situ” data taken are considered appropriate.
Once the field research is finished, all the information obtained together with the results of
the questionnaire is integrated and processed. A previous information treatment process
based on a quality control of the preliminary data must be performed. This can be done
through the design of a software program for automated information analyses.
Firstly, it must be checked that all the necessary data for each dwelling exist that means
that there are not “gaps”.
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STANDARDIZATION OF METHODOLOGIES
Secondly, the correspondence between the power of all the energy consuming
equipment, obtained from the questionnaires, and the overall power installed in the
dwelling must be checked.
Thirdly, the correspondence between the consumptions indicated in the invoices of each
dwelling and the sum of all the consumptions related to the energy consuming equipment
must be checked for the period corresponding to the one considered in the invoices.
4.5.
EXTRAPOLATION
Once the information is depurated it must be extrapolated to the universe of all the
households through the use of extrapolating factors referred to the different geographic
(climate) zones and types of dwellings.
The extrapolated information should be contrasted with official information obtained from
other sources in order to have a better validation of results.
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STANDARDIZATION OF METHODOLOGIES
ANNEX I: SAMPLE QUESTIONNAIRE
This questionnaire aims at exemplifying the development of the standard proposed adhoc survey which should be taken into consideration by every EU country in order to
harmonize statistics on energy consumption in the residential sector. The design has been
carried out according to the requirements established by the Task Force 2008. Additionally,
some questionnaires implemented by some EU countries and related to the SECH project
have been taken into consideration.
IDENTIFICATION RECORD OF THE RESPONDENT HOUSEHOLD
To be completed by the person who carries out the survey
QUIESTIONNAIRE IDENTIFICATION
DATE
HOUR
NUT
Apartment
Attached......
Type of dwelling
Interviewer
Number of questionnaire
¿is survey complete?
01.
02.
Yes
No
Good morning/evening:
IDAE is doing a survey on "Energy consumption in households". For this we need to get all the
necessary information about your home and energy that takes. For this reason, it is necessary to
interview the person responsible for the household.
Your household has been selected to participate in this survey and we guarantee absolute
anonymity and confidentiality of their responses in strict compliance with the laws on data
protection. Once recorded information anonymously questionnaires will be destroyed immediately.
Thank you very much for your cooperation.
1.-Housing Stock Characteristics
1. Is this dwelling your permanent residence?
o
YES
o
NO
Note for the interviewer: If the dwelling is not the permanent residence of the household (a
dwelling is considered as permanent if it is occupied for at least six months per year by the
household) end of interview.
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STANDARDIZATION OF METHODOLOGIES
2. Professional activity carried out within the residence area by the household and
results to the consumption of important amounts of energy:
o
o
o
o
None
Agriculture
Manufacturing
Other professional/economic activity
Note for the interviewer: If the answer to question 2 is one of the options 2, 3, 4 it should
be clarified to the interviewed person that the consumption of energy due to a
professional activity carried out within the residence area should not be included in
his/her answers to the rest of the questions.
3. In this dwelling you and your household live:
o
o
The whole year
Only for a few months per year. Specifically: |__|__|month
4. Type of residence:
o
o
o
o
o
o
Detached single house
Semidetached single house
Terraced houses
Apartment in a building with less than 10 apartments in total
Apartment in a building with more than 10 apartments in total
Other
5. The household’s residence is:
o
o
o
Owned
Rented
Provided for free
6. How many regular rooms does your dwelling have? (excluding kitchen, bathroom,
toilet and hallway)
o
o
Number of rooms |_|_|
How many of these does your household use? |_|_|
7. Area of residence in square meters:
o
o
o
o
o
o
o
o
Less than 5
51-100
101-150
151-200
201-250
251-300
301-350
Over 350
8. How many floors does the building have?
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STANDARDIZATION OF METHODOLOGIES
o
Number of floors |_|_|
9. Construction year of the dwelling:
o
o
o
o
o
o
o
o
o
before 1946
1946 – 1960
1961 – 1980
1981 – 1990
1991 – 1995
1996 – 2000
2001 – 2005
2006 – 2010
After 2012
10. Area of residence which was heated during the cold season of the year 2012
(period 1/1/12 until 31/12/12) in square meters:
o
o
o
o
o
o
o
o
Less than 51
51-100
101-150
151-200
201-250
251-300
301-350
Over 350
Exact area in square meters |_|_|_|
11. Area of residence in which air conditioning was used for cooling during the hot season
of the year 2012 (period 1/1/2012 until 31/12/2012) in square meters:
o
o
o
o
o
o
o
o
Less than 51
51-100
101-150
151-200
201-250
251-300
301-350
Over 350
Exact area in square meters |_|_|_|
12. Heat insulation of residence. Presence of thermal insulation of:
o
o
o
o
External walls
Floor
Loft/roof
Windows
13. Improvement work carried-out over the last year to reduce energy consumption.
Improvement work for:
o
o
o
o
o
The roof and its insulation
Exterior wall insulation
Windows
Heating system
Air conditioning equipment
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STANDARDIZATION OF METHODOLOGIES
2.-Households Characteristics
14. How many people live in your household?
o
Indicate number |_|_|
15. How much is the total annual income in net terms (for 2012) of the household in Euros?
o
o
o
o
o
o
o
o
<= 10.000 €
10.001-20.000 €
20.001-30.000 €
30.001-40.000 €
40.001-55.000 €
55.001-70.000 €
70.001-100.000 €
> 100.000 €
16. In which periods of the day is your household occupied by someone, on working days?
o
o
o
Morning
Afternoon
Night
17. In which periods of the day is your household occupied by someone, at the
weekends?
o
o
o
Morning
Afternoon
Night
18. In which periods of the day is your household occupied by someone, on holidays?
o
o
o
Morning
Afternoon
Night
19. Does your household have any unoccupied inner zone, aside from rooms?
o
o
YES
NO
20. Number of rooms that are usually unoccupied
o
Indicate number |_|_|
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STANDARDIZATION OF METHODOLOGIES
3.-Expenditure of energy commodities
21. Please specify fuels and energy commodities, consumed in your household in the year
2012.
o
o
o
o
o
o
o
o
o
o
Anthracite
Brown coal
Briquettes (BKB)
Butane
Charcoal
District heating
Electricity
Gas Works Gas
Geothermal
Heating gas oil
Heavy oil
o
o
o
o
o
o
o
o
o
Hydro power
Kerosenes
Natural gas
Other Bituminous
coal
Peat briquettes
Peat Pellets
Propane
Semi-coke
Sewages Sludge
Gas
o
o
o
o
Solar
photovoltaic
Solar Thermal
Wind
Wood, Wood
Wasted and
Other Solid
Wastes
30
STANDARDIZATION OF METHODOLOGIES
31
STANDARDIZATION OF METHODOLOGIES
4.-Space Heating
22. Do you use any space heating system/equipment?
o
YES
o
NO
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STANDARDIZATION OF METHODOLOGIES
23. What is the main space heating system that you use?
o
o
Central heating system
Independent heating system
24. The main type of heating equipment/system used in your residence is:
o
o
o
o
o
o
o
o
o
Central Steam/Hot Water Space Heating System
Built-in Electric System
Central Warm-Air Space Heating System
Heat Pumps
Stove
Fireplace
Electric storage heaters, portable electric heaters
Portable kerosene/LPG heaters
Other
25. Age of main heating system in years
o
o
o
o
o
o
<=5
6-10
11-15
16-20
21-25
>25
26. How many months was your main heating system in operation during the period
1/1/2012 to 31/12/2012?
o
o
o
o
o
o
o
o
<1
1
2
3
4
5
6
>7
27. Average daily hours of operation of the main heating system during the period of use:
o
o
o
o
o
o
o
<=2
3-5
6-8
9-11
12-14
15-17
>17
28. Annual consumption and expenditure for space heating purposes (for the period
1/1/12 to 31/12/12):
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STANDARDIZATION OF METHODOLOGIES
Consumption
Expenditure
in euros
YES NO
o Anthracite
o Brown coal Briquettes (BKB)
o Butane
o Charcoal
o District heating
o Electricity
o Gas Works Gas
o Geothermal
o Heating gas oil
o Heavy oil
o Hydro power
o Kerosenes
o Natural gas
o Other Bituminous coal
o Peat briquettes
o Peat Pellets
o Propane
o Semi-coke
o Sewages Sludge Gas
o Solar photovoltaic
o Solar Thermal
o Wind
o Wood, Wood Wasted and
Other Solid Wastes
29. Is your main heating system equipped with a thermostat?
o
o
YES
If yes, at which temperature is it set?
NO
|_|_| 0C
Note for the interviewer: If the answer to question 29 is ‘NO’ proceed to question 32
34
STANDARDIZATION OF METHODOLOGIES
30. Is your main heating system equipped with?
o
o
A central thermostat
Multiple thermostats in different rooms
31. Is/are the thermostat/s of your main heating system programmable or not?
o
o
Programmable
Non programmable.
5.-Water heating
32. Do you use any Water Heating system/equipment?
o
YES
o
NO
33. Water heating equipment/system used in your residence is:
o
o
o
o
Combi Boiler
Water Heater
Heater instant DHW
Other
34. Age of main water heating system in years
o
o
o
o
o
o
<=5
6-10
11-15
16-20
21-25
>25
35. Is your residence equipped with hot water storage tank/s?
o
o
YES
NO
Note for the interviewer: If the answer to question 35 is ‘NO’ proceed to question 37.
36. Total capacity of hot water storage tank in litres:
o
o
o
o
o
o
<100
100-149
150-199
200-249
250-299
>=300
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STANDARDIZATION OF METHODOLOGIES
37. Annual consumption and expenditure for water heating purposes (for the period
1/1/12 to 31/12/12):
Consumption
Expenditure
in euros
YES NO
o Anthracite
o Brown coal Briquettes (BKB)
o Butane
o Charcoal
o District heating
o Electricity
o Gas Works Gas
o Geothermal
o Heating gas oil
o Heavy oil
o Hydro power
o Kerosenes
o Natural gas
o Other Bituminous coal
o Peat briquettes
o Peat Pellets
o Propane
o Semi-coke
o Sewages Sludge Gas
o Solar photovoltaic
o Solar Thermal
o Wind
o Wood, Wood Wasted and
Other Solid Wastes
36
STANDARDIZATION OF METHODOLOGIES
6.-Cooking
38. Equipment used for cooking, average time of use per week (in minutes) and age of
equipment:
Minutes
of use
Age
YES NO
o Cooker
o Oven
o Hob
o Cooking stove
o Microwave oven
o Extractor hood
o Minor Equipment
39. Energy source used for cooking and corresponding consumption during the year 2012
(period 1/1/12 to 31/12/12):
Consumption
Expenditure
in euros
YES NO
o Anthracite
o Brown coal Briquettes (BKB)
o Butane
o Charcoal
o Electricity
o Gas Works Gas
o Heating gas oil
o Hydro power
o Kerosenes
o Natural gas
o Other Bituminous coal
o Peat briquettes
o Peat Pellets
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STANDARDIZATION OF METHODOLOGIES
o Propane
o Semi-coke
o Sewages Sludge Gas
o Solar photovoltaic
o Solar Thermal
o Wind
o Wood, Wood Wasted and
Other Solid Wastes
7.-Air Conditioning
40. Air conditioning: Do you use any system/units for cooling some space in your residence
during the hot season?
o
o
YES
NO
Note for the interviewer: If the answer to question 40 is ‘NO’ proceed directly to part 8,
question.
41. Technical characteristics of air conditioning units:
Number
Age
Power
(BTU/hr)
Power
(KW)
YES NO
o Individual Units
o Central System
42. How many months was your air conditioning in operation during the period 1/1/2012 to
31/12/2012?
o
o
o
o
o
o
o
o
<1
1
2
3
4
5
6
>7
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STANDARDIZATION OF METHODOLOGIES
43. Average daily hours of operation of the air conditioning during the period of use:
o
o
o
o
o
o
o
<=2
3-5
6-8
9-11
12-14
15-17
>17
44. Is your main air conditioning system equipped with a thermostat?
o
o
YES
If yes, at which temperature is it set?
NO
|_|_| 0C
Note for the interviewer: If the answer to question 44 is ‘NO’ proceed to question 47
45. Is your main air conditioning system equipped with?
o
o
A central thermostat
Multiple thermostats in different rooms
46. Is/are the thermostat/s of your main air conditioning system programmable or not?
o
o
Programmable
Non programmable.
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STANDARDIZATION OF METHODOLOGIES
8.-Electrical Appliances
47. Electrical appliances: Number and weekly time of use (in hours):
Number
Hours of
use
Labelled
equipment
YES NO
o Refrigerator
Refrigreration o Freezer
o Other
o Clothes washer
Laundry
o Clothes dryer
o Other
Diswasher
o Diswasher
o Colour televisions
o Satellite antennas
Home
Entertainment o VCR / DVD and music equipment
o Video game console.
o Other
o Personal computer
Home office
o Printer
o Internet/modem
o Other
o Cordless Phone
o Cell Phone
Rechargeable
o Digital Camera
devices
o Other
o Vacuum-cleaner
Cleaning and
o Ceiling fans
small
o Humidifier
equipment
o Other
o Incandescent lamps (or "bulbs")
o Fluorescent tube lamps
Lighting
o Compact fluorescent lamps (CFLs)
o Halogen lighting
o LED lamps
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STANDARDIZATION OF METHODOLOGIES
48. Do you usually keep your electrical appliances on standby mode?
o
o
YES
NO
9.-Penetration of energy renewable technologies
49. Is your residence equipped with solar panels (either for hot water or heating use)?
o
o
YES
NO
50. In case the residence is equipped with solar panels please distinguish their kind,
number, area and power:
Number
Age
Surface
YES NO
o Solar Collectors
o Photovoltaic panels
51. Is your residence equipped with a heat pump?
o
o
YES
NO
52. In case the residence is equipped with heat pump please distinguish their kind:
Power
(KW)
Electricity
consumption
YES NO
o Heat pump air-air
o Heat pump water-water
o Heat pump ground-water
o Heat pump air-water
53. Is your residence equipped with a small wind electric system?
o
YES
o
o
o
If yes, please indicate the following:
Is it autonomous
Capacity |_|_| kW24
NO
41
Power
(KW)
STANDARDIZATION OF METHODOLOGIES
ANNEX II: “IN SITU MEASUREMENTS”
In this annex the method of "In situ measurements" developed in Spain is explained as a
standard methodology to apply in the rest of countries.
The analyses of the electricity consumption of the Spanish households by means of
measurements, has been developed in the following stages: “in situ” measurements;
obtaining of preliminary results; results debugging; and obtaining of final results.
Figure 1: Methodological scheme of the procedure followed to obtain the results
1. “In situ”
measurement
2.
3.
Preliminary
Filter of
Results
results
4.
Final results
Additional information
from previous
studies/projects
The starting point was a sample of 600 dwellings “type” (the initial dwellings-type where
the measurement could not be taken, were replaced with other of similar characteristics,
in order to assure the measurements in a sample of 600 dwellings-type), representative of
the three main climate zones of Spain (Atlantic, Continental, and Mediterranean),
considering 2 types of dwellings (single family houses and dwellings in multifamily houses).
The measurements were addressed to the permanently occupied dwellings. The selection
of dwellings was made with enough representativeness with regard to their characteristics
and location. The selection criteria integrated energy, geographic and socioeconomic
factors.
The measurements were taken in the period from 21st June to 23rd march (the spring
season was assimilated to autumn because of the similarity of temperatures and energy
demands) in accordance to the following planning:
 Summer season: since 21st June till 23rd September,
 Autumn season: since 24th September till 23rd December,
 Winter season: since 24th December till 23rd March,
The measurements were accompanied by a questionnaire addressed to the equipment,
their technical characteristics and pattern of use, differentiating between working days
and festivities. The questionnaire included a request on information based on the
electricity invoices corresponding to the last 12 months.
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STANDARDIZATION OF METHODOLOGIES
In order to take the measurements 600 electricity consumption measurer equipment kits
were used. Moreover, for each type of dwelling and climate zone (six in total), an
electricity consumption register equipment was installed. This equipment is more powerful
than the aforementioned (measurer equipment) and is connected to the main
switchboard of the household. It provides enough information by taking hourly
measurement during a determinate period. Additionally, the register equipment can store
information hour by hour; so that the real load curves can be obtained, being additionally
very useful for aspects such as the measurement of standby and/or the peak demands.
The measurement equipment provided information on the electricity consumption (kWh)
along the period of measurements as well as the time of operation of the measurement
equipment. In order to assure the measurements in working days and festivities, the
measurement equipment kits were installed for 4 consecutive days in each household,
mainly from Thursdays to Sundays.
The incidences encountered during the measurement phase were of two types:
measurement equipment failure, and problems of access to some electricity consuming
equipment, such as the ovens. When some of these incidences appeared, the procedure
followed was the following:
 If some measurement equipment stopped taking measures for whatever reason during
the measurement phase: another measurement equipment unit was installed
whenever it was possible in the same day. On the opposite side, another measurement
equipment unit was installed in the next week, during the same week days.
 If consuming equipment couldn’t be measured because of accessibility problems, then
the preliminary results were estimated on the basis of other measurements realized in
similar consuming equipment.
During the field research, a triple quality control was applied:
 A check on all the information received by the team of technicians, to verify that all the
data had been properly taken (measured). On the opposite side, individual revisions
were implemented.
 Individual check on 5% of the “in situ” measured data, both during the measurements
in the households, and through personal meetings with the technicians.
 Every two months some meetings were organized among the teams in charge of the
measurements, both on the level of a same climate zone, and on the level of the whole
of climate zones.
Once the field research was finished, all the information obtained together with the
questionnaire was integrated and processed. The preliminary results were obtained
through a “bottom-up” method complemented with a “top-down” method. That is, a
system which generates updated consumption curves, taking as inputs:
 Data obtained from the measurement equipment installed in the households.
 Data from the questionnaire.
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STANDARDIZATION OF METHODOLOGIES
 Data from the consumption “type” curves of each electrical equipment, known from
former studies/projects. The consumption “type” curves, derived from previous studies,
were used to weight the curves generated with the information obtained from the
measurement equipment and the questionnaire data. These curves allowed to put on
a homogeneous basis all the information obtained from the field research, with the aim
of extrapolating the measurements, with the least margin of error possible, to the rest of
households of Spain.
 Data obtained from the energy registers.
 Data from the electricity invoices: which allowed adjusting the load curves of the
household in the period included in the invoice.
The aforementioned procedure was accompanied by a filtering process through a quality
control of the preliminary results. This was developed through the design of a specific
software program for automated information analyses. The following checks took place:
 Absence of “gaps”: availability of all the necessary data corresponding to the
equipment available in the households.
 Correspondence between the sums of the power of all the equipment, obtained from
the questionnaires, with the total power installed in the households.
 Correspondence between the consumptions related to the invoices of each household
and the sums of the consumptions of all the equipment available in the household, for
the period corresponding to the invoices.
Once the filter of the preliminary results was performed, it was applied an adjustment of
those values which did not overcome the required quality parameters, and eventually the
final values were obtained.
The debugged information was extrapolated to the universe of households by means of
elevation factors for each geographical zone and type of dwelling. For the elevation of
the results corresponding to each type of equipment, climate zone and type of dwelling,
the information about the equipment obtained from the face-to-face and phone surveys,
developed in parallel to the “in situ” electricity measurements, were used.
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