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Report 5. Standardization of Methodologies

AUGUST 2012 2012

MANUAL FOR STATISTICS ON ENERGY CONSUMPTION IN

HOUSEHOLDS- MESH PROJECT -

STANDARDIZATION OF METHODOLOGIES

ÍNDEX

1. STANDARDIZATION..........................................................................41.1. INTRODUCTION.............................................................................41.2. GENERAL ISSUES..........................................................................5

2. INFORMATION SOURCE: SURVEY...................................................112.1. ESTABLISHMENT OF PURPOSES..................................................112.2. ORGANIZATION OF THE FIELDWORK..........................................122.3. INCIDENCES AND TREATMENT....................................................122.4. 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............................................................142.6. DATA COLLECTION......................................................................162.7. DATA CLEANING..........................................................................162.8. VALIDATION................................................................................162.9. EXTRAPOLATION.........................................................................17

3. STATISTICAL METHODS: MODELLING............................................183.1. OBJECTIVE...................................................................................183.2. DATA SOURCES (INPUTS)............................................................193.3. METHODOLOGY..........................................................................193.4. CORRECTIONS, ADJUSTMENTS AND REVISIONS..........................203.5. PUBLISHING................................................................................20

4. STATISTICAL METHODS: IN SITU MEASUREMENT..........................224.1. PURPOSE.....................................................................................224.2. SAMPLE DESIGN..........................................................................224.3. METHODOLOGICAL DEVELOPMENT.............................................23

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4.4. CLEANING AND CONTROL...........................................................244.5. EXTRAPOLATION.........................................................................25

ANNEX I: SAMPLE QUESTIONNAIRE........................................................26

ANNEX II: “IN SITU MEASUREMENTS”.....................................................42


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

Standardization plays an important role concerning the quality of the statistical information produced, as it serves as a tool for diagnosing problems, performing 1 This definition has been used in a meeting of the MESH project, according to the literature available on the subject.

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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.

1.2. GENERAL ISSUES 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; “Metodología para la estandarización de Conceptos” (“Methodology for standardization of concepts”), National Bureau 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: - 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.

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- 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

ObjectsIn 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 sources5. Accuracy of statistical data6. Meta data.7. Processes.8. Reporting burden.9. Output specifications for external customers. 10. Quality documentation and reports.11. Revisions.12. Statistical concepts.13. Statistical data.14. Statistical output.

Next, each of the objects concerning the standardization is described. 1) Methodology

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Initial inventory of concepts/methods.. obtained from glossaries, NSIs, etc. of

the countries considered in the geographic coverage

Review, adjustment

and depuration

Criteria to standardize

concepts/methods

Selection of a glossary of

concepts/methods

(1) Relevant concepts/methods for the design anddevelopmentof thestatistical operations;

(2) Concepts/methods of interesttoconsider

(1) Accordance with international officialguidelines/recommendationsor theory;

(2) Other concepts/methods

Standardized 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

populationA 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 data4. Correctness of data5. Coherence of data items with the statistical concept of the output6. 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.The accuracy of data depends on:1. The implementation of the different steps in the statistical process and2. 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

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- 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. Efficiency2. CompletenessEfficiency 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. Level2. Spreading3. 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.

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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. Availability2. Compliance with Eurostat regulations3. Compliance with agreements with other users

4. Punctuality of provision11) Corrections, adjustments and revisions.

The following characteristics of corrections, adjustments and revisions are distinguished:1. Compliance with guidelines

2. Existence of analysis12) 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.2. Comparability3. 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. Clarity2. Accessibility

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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 individualsAs 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

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Obtaining information that can be compared among countries.

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 processThus, 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

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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.

2.4. SAMPLE DESIGN

2.4.1. 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.

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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.

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 2 As it is defined in the report: “Handbook of Recommended Practices for Questionnaire Development and Testing in the European Statistical System”.

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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.

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),

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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.

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

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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. V ALIDATION 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.

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 sub-sample. 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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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 structure3. 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.

Efficacy and efficiency will be pursued from the very first moment.

3 An exhaustive list of the different energy commodities has been explained in Report 7.

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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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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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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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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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4.3. METHODOLOGICAL DEVELOPMENT

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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[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.

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o Built-in Electric Systemo Central Warm-Air Space Heating Systemo Heat Pumpso Stoveo Electric storage heaters, portable electric heaterso Combi Boilero Water Heatero Heater instant DHWo Cookero Oven o Cooking stoveo Microwave oveno Extractor hoodo Air conditionero Heat Pumpso Refrigeratoro Freezero C lothes washero C lothes dryero Diswashero Colour televisionso Personal computero Printero Vacuum-cleanero Other electrical appliances

Electrical systems for use

Space Heating

Water Heating

Cooking

Air conditioning

Appliances


Firstly, it must be checked that all the necessary data for each dwelling exist that means that there are not “gaps”. 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.

4.4.[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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ANNEX I: SAMPLE QUESTIONNAIRE

This questionnaire aims at exemplifying the development of the standard proposed ad-hoc 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 HOUSEHOLDTo be completed by the person who carries out the survey

QUIESTIONNAIRE IDENTIFICATION

DATE

HOUR

NUT

Type of dwellingApartmentAttached......

Interviewer

Number of questionnaire

¿is survey complete? 01. Yes02. 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 Characteristics1. 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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2. Professional activity carried out within the residence area by the household andresults to the consumption of important amounts of energy:

o None o Agriculture o Manufacturing o 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 The whole yearo Only for a few months per year. Specifically: |__|__|month

4. Type of residence:

o Detached single houseo Semidetached single houseo Terraced houseso Apartment in a building with less than 10 apartments in totalo Apartment in a building with more than 10 apartments in totalo Other

5. The household’s residence is:

o Owned o Rented o Provided for free

6. How many regular rooms does your dwelling have? (excluding kitchen, bathroom, toilet and hallway)

o Number of rooms |_|_|o How many of these does your household use? |_|_|

7. Area of residence in square meters:

o Less than 5o 51-100 o 101-150 o 151-200 o 201-250 o 251-300 o 301-350 o Over 350

8. How many floors does the building have?

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o Number of floors |_|_|

9. Construction year of the dwelling:

o before 1946o 1946 – 1960o 1961 – 1980o 1981 – 1990o 1991 – 1995o 1996 – 2000o 2001 – 2005o 2006 – 2010o 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 Less than 51 o 51-100 o 101-150 o 151-200 o 201-250 o 251-300 o 301-350 o 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 Less than 51 o 51-100 o 101-150 o 151-200 o 201-250 o 251-300 o 301-350 o Over 350

Exact area in square meters |_|_|_|

12.Heat insulation of residence. Presence of thermal insulation of:

o External wallso Flooro Loft/roof o Windows

13.Improvement work carried-out over the last year to reduce energy consumption. Improvement work for:

o The roof and its insulationo Exterior wall insulationo Windowso Heating systemo Air conditioning equipment

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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 <= 10.000 € o 10.001-20.000 € o 20.001-30.000 € o 30.001-40.000 € o 40.001-55.000 € o 55.001-70.000 € o 70.001-100.000 € o > 100.000 €

16. In which periods of the day is your household occupied by someone, on working days? o Morning o Afternoono Night

17. In which periods of the day is your household occupied by someone, at the weekends?o Morningo Afternoono Night

18. In which periods of the day is your household occupied by someone, on holidays? o Morning o Afternoon o Night

19.Does your household have any unoccupied inner zone, aside from rooms? o YES o NO

20.Number of rooms that are usually unoccupiedo Indicate number |_|_|

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3.-Expenditure of energy commodities

21.Please specify fuels and energy commodities, consumed in your household in the year 2012.o Anthracite o Brown coal

Briquettes (BKB)o Butaneo Charcoalo District heatingo Electricity o Gas Works Gaso Geothermalo Heating gas oil

o Heavy oil o Hydro power o Keroseneso Natural gaso Other

Bituminous coalo Peat briquetteso Peat Pelletso Propaneo Semi-coke

o Sewages Sludge Gas

o Solar photovoltaic

o Solar Thermalo Windo Wood, Wood

Wasted and Other Solid Wastes

29


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4.-Space Heating

22.Do you use any space heating system/equipment?o YES o NO

23.What is the main space heating system that you use?

31


o Central heating systemo Independent heating system

24.The main type of heating equipment/system used in your residence is:o Central Steam/Hot Water Space Heating Systemo Built-in Electric Systemo Central Warm-Air Space Heating Systemo Heat Pumpso Stoveo Fireplaceo Electric storage heaters, portable electric heaterso Portable kerosene/LPG heaterso Other

25.Age of main heating system in yearso <=5o 6-10o 11-15o 16-20o 21-25o >25

26.How many months was your main heating system in operation during the period 1/1/2012 to 31/12/2012?o <1o 1o 2o 3o 4o 5o 6o >7

27.Average daily hours of operation of the main heating system during the period of use:o <=2o 3-5o 6-8o 9-11o 12-14o 15-17o >17

28.Annual consumption and expenditure for space heating purposes (for the period 1/1/12 to 31/12/12):

Consumption

Expenditure in euros

32


YES NO

o Anthraciteo Brown coal Briquettes (BKB)o Butaneo Charcoalo District heatingo Electricityo Gas Works Gaso Geothermalo Heating gas oilo Heavy oilo Hydro powero Keroseneso Natural gaso Other Bituminous coalo Peat briquetteso Peat Pelletso Propaneo Semi-cokeo Sewages Sludge Gaso Solar photovoltaico Solar Thermalo Windo Wood, Wood Wasted and Other Solid Wastes

29. Is your main heating system equipped with a thermostat?o YES

If yes, at which temperature is it set? |_|_| 0Co NO

Note for the interviewer: If the answer to question 29 is ‘NO’ proceed to question 32

30.Is your main heating system equipped with?

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o A central thermostat o Multiple thermostats in different rooms

31.Is/are the thermostat/s of your main heating system programmable or not?o Programmable o 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 Combi Boilero Water Heatero Heater instant DHWo Other

34.Age of main water heating system in yearso <=5o 6-10o 11-15o 16-20o 21-25o >25

35.Is your residence equipped with hot water storage tank/s?o YES o 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 <100o 100-149o 150-199o 200-249o 250-299o >=300

37.Annual consumption and expenditure for water heating purposes (for the period 1/1/12 to 31/12/12):

34


Consumption


35


YES NO

o Anthraciteo Brown coal Briquettes (BKB)o Butaneo Charcoalo District heatingo Electricityo Gas Works Gaso Geothermalo Heating gas oilo Heavy oilo Hydro powero Keroseneso Natural gaso Other Bituminous coalo Peat briquetteso Peat Pelletso Propaneo Semi-cokeo Sewages Sludge Gaso Solar photovoltaico Solar Thermalo Windo Wood, Wood Wasted and Other Solid Wastes

6.-Cooking

38.Equipment used for cooking, average time of use per week (in minutes) and age of equipment:

Minutes of use Age

36


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


YES NO

o Anthraciteo Brown coal Briquettes (BKB)o Butaneo Charcoalo Electricityo Gas Works Gaso Heating gas oilo Hydro powero Keroseneso Natural gaso Other Bituminous coalo Peat briquetteso Peat Pelletso Propaneo Semi-cokeo Sewages Sludge Gaso Solar photovoltaico Solar Thermalo Windo Wood, Wood Wasted and Other Solid Wastes

37


7.-Air Conditioning

40.Air conditioning: Do you use any system/units for cooling some space in your residence during the hot season?o YES o 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 <1o 1o 2o 3o 4o 5o 6o >7

43.Average daily hours of operation of the air conditioning during the period of use:o <=2o 3-5o 6-8o 9-11o 12-14o 15-17o >17

44.Is your main air conditioning system equipped with a thermostat?

38


o YES If yes, at which temperature is it set? |_|_| 0C

o NO

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 A central thermostat o Multiple thermostats in different rooms

46.Is/are the thermostat/s of your main air conditioning system programmable or not?o Programmable o Non programmable.

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8.-Electrical Appliances

47.Electrical appliances: Number and weekly time of use (in hours):

Number Hours of use

Labelled equipmen

tYES NO

Refrigrerationo Refrigeratoro Freezero Other

Laundryo Clothes washero Clothes dryero Other

Diswasher o Diswasher

Home Entertainmen

t

o Colour televisionso Satellite antennaso VCR / DVD and music equipmento Video game console.o Other

Home officeo Personal computero Printero Internet/modemo Other

Rechargeable devices

o Cordless Phoneo Cell Phoneo Digital Camerao Other

Cleaning and small

equipment

o Vacuum-cleanero Ceiling fanso Humidifiero Other

Lighting

o Incandescent lamps (or "bulbs")o Fluorescent tube lampso Compact fluorescent lamps (CFLs)o Halogen lightingo LED lamps

48.Do you usually keep your electrical appliances on standby mode?

40


o YES o NO

9.-Penetration of energy renewable technologies

49.Is your residence equipped with solar panels (either for hot water or heating use)?o YES o NO

50.In case the residence is equipped with solar panels please distinguish their kind, number, area and power:

Number Age Surface Power (KW)

YES NO

o Solar Collectors

o Photovoltaic panels

51. Is your residence equipped with a heat pump?o YES o NO

52.In case the residence is equipped with heat pump please distinguish their kind:

Power (KW)

Electricity consumptio

nYES NO

o Heat pump air-air

o Heat pump water-water

o Heat pump ground-watero Heat pump air-water

53. Is your residence equipped with a small wind electric system?o YES

If yes, please indicate the following:o Is it autonomous o Capacity |_|_| kW24

o NO

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1. “In situ” measurement 2. Preliminary Results

3. Filter of results 4.

Final results

Additional information from previous studies/projects


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

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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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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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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