ESS Standard for Quality Reports Structure (ESQRS)
National Statisitcal Institute
|Contact organisation unit|
Environmental and Energy Accounts Department
Irina Dencheva - electricity prices
Iveta Minkova - natural gas prices
|Contact person function|
|Contact mail address|
2 P.Volov street, 1038 Sofia, Bulgaria
|Contact email address|
|Contact phone number|
+359 2 9857 625
+359 2 9857 191
|Contact fax number|
This topic presents average semestrial prices of supplied electricity/natural gas to household and final non-household customers. Prices are representative for the country - data are provided by all suppliers of electricity/natural gas to household and final non-household customers for the quantities delivered through transmission/distribution network. Prices include electricity/gas basic price, transmission, distribution, excise, VAT and others.The prices are calculated as a weighted average price by the actual supplied quantity of electricity/natural gas and their invoiced value of all end-customers for the reference period in the following 2 directions:
A) Components and sub-components:
These data are collected every semester, but are reported annually as an arithmetic average prices.
These data are collected and reported twice per year - every semester.
Internal Eurostat classification system according to Regulation (EU) 2016/1952 of the European Parliament and of the Council on natural gas and electricity prices and repealing Directive 2008/92/EC, based on annual natural gas/electricity consumption bands and on tax levels.
Gas and electricity prices are collected for the 2 following areas:
|Statistical concepts and definitions|
Reference customers of natural gas and electricity are characterised by the following standard annual consumption bands:
Natural gas household customers:
D1 (Small): annual consumption below 20 GJ
D2 (Medium): annual consumption between 20 and 200 GJ
D3 (Large): annual consumption above 200 GJ
Natural gas final non-household customers:
I1: annual consumption below 1 000 GJ
I2: annual consumption between 1 000 and 10 000 GJ
I3: annual consumption between 10 000 and 100 000 GJ
I4: annual consumption between 100 000 and 1 000 000 GJ
I5: annual consumption between 1 000 000 and 4 000 000 GJ
I6: annual consumption above 4 000 000 GJ
Electricity household customers:
D1 (Very small): annual consumption below 1 000 kWh
D2 (Small): annual consumption between 1 000 and 2 500 kWh
D3 (Medium): annual consumption between 2 500 and 5 000 kWh
D4 (Large): annual consumption between 5 000 and 15 000 kWh
D5 (Very large): annual consumption above 15000 kWh
Electricity final non-household customers:
I1: annual consumption below 20 MWh
I2: annual consumption between 20 and 500 MWh
I3: annual consumption between 500 and 2 000 MWh
I4: annual consumption between 2 000 and 20 000 MWh
I5: annual consumption between 20 000 and 70 000 MWh
I6: annual consumption between 70 000 and 150 000 MWh
I7: annual consumption above 150 000 MWh
Two different levels for disagregation of prices exist:
1) Semestrial prices:
These prices are reported twice a year and are divided in 3 tax levels:
Level 1 prices: Prices excluding taxes and levies.
Level 2 prices: Prices excluding VAT and other recoverable taxes and levies.
Level 3 prices: Prices including all taxes and levies.
2) Annual prices:
These prices are reported once a year together with the data for the second semester and are divided into the following 3 main components:
For electricity - includes costs for generation, aggregation, balancing energy, supplied energy costs, customer services, after-sales management and other supply costs.
For natural gas - includes the commodity price for natural gas paid by the supplier or the price of natural gas at the point of entry into the transmission system, including, if applicable, the following end-user costs: storage costs plus costs relating to the sale of natural gas to final customers.
Final household and non-household customers divided into annual consumption bands.
All final non-household (until the first semester of 2017 only end-users in the industry were observed) and household customers, meeting the criteria in Regulation (EU) 2016/1952.
Final non-household customers:
For the natural gas prices, data are provided by 23 out of 23 gas suppliers through mains and represent 100% of the final non-household customers. The companies -non-household customers, using natural gas for electricity generation and non-energy use are excluded.
For the electricity prices, data are provided by 50 out of 50 electricity suppliers and represent 100% of the final non-household customers.
For the natural gas prices, data are provided by 17 out of 23 gas suppliers and represent 100 % the household customers. Six companies-gas suppliers do not supply household customers.
For the electricity prices, data are provided by 28 out of 50 electricity suppliers and represent 100% the household customers. The other 22 suppliers do not supply electricity to household customers.
The national territory of the Republic of Bulgaria.
From the second semester of 2007 onwards.
Data are provided by all suppliers of natural gas and electricity to household and final non-household customers through a specific statisitcal survey "Electricity and natural gas prices to household and final non-household customers", included in the National Statistical Programme.
|Frequency of data collection|
Biannual for the periods January - June and July - December.
Exhaustive survey on average gas and electricity prices from all suppliers to final customers with electronic statistical form. Reports are received by email.
A comparative analysis of the reported data is made with the data of previous periods and with the established tariffs for price caps of natural gas and tariffs for the electricity.
Three levels of average prices in the country are estimated by standard group of end-customers. Appropriate quantities of natural gas and electricity, delivered by each supplier are used as weights.
NSI has developed and implemented an Integrated Information Quality and Security Management System (ISM) in accordance with the international standards ISO 9001: 2015 and ISO / IEC 27001: 2013:
The implementation of ISM includes: Management Regulation, Procedures, Instructions, Information Security Policies, Risk Assessment Methodology, ISM Training, Reports, Audit. The NSS quality assurance framework includes methods and tools that aim to ensure compliance with the requirements for statistical processes and products and to ensure the necessary quality of statistical information:
Dataset provides prices information, comparable between countries, as prices are calculated on the base of Eurostat's methodology for electricity/natural gas data collection (Regulation (EU) 2016/1952, Annex 1 and 2). Data are with good quality.
No information available for users of these data, as they have free access to the website of NSI.
No user satisfaction survey has been carried out for this dataset.
Data fully meet the requirements of Regulation (EU) 2016/1952 - in terms of scope, structure of consumers and price levels.
|Data completeness - rate|
|Accuracy and reliability|
Data are reliable, the accuracy is good. Data are verified for each supplier. The comparative analysis of the data providers is made with data from previous periods and with the decisions and the tariffs for approved prices respectively of natural gas and electricity, published by EWRC - Energy and Water Regulatory Commission.
No sampling used as the data covers 100% of the population.
|Sampling errors - indicators|
The information is included in the following 9 indicators.
Not available. As 100% of the population (household and final non-household customers) is covered by the data, all kinds of unit are represented.
|Over-coverage - rate|
There is no over-coverage in the data.
|Common units - proportion|
100% of the data come from the survey.
The responding units and statistical experts are not exempted automatically from errors in entering, calculating and recording the numerical values. As the Excel questionnaire for collecting primary data and summary files are not automated, these errors are verified and corrected manually.
|Non response error|
There are no non-responce errors.
|Unit non-response - rate|
The unit non-response rate is 0%.
|Item non-response - rate|
The item non-response rate is 0%.
Gas/electricity price questionnaires for collecting primary data from the suppliers are Excel formatted. At national level all data is aggregated manually in Summary Excel files where national data (previously checked and verified) are calculated by formulas. For this reason no processing errors occurre. No specific tool is used and calculations are not automated.
|Imputation - rate|
|Model assumption error|
|Data revision - policy|
Data revisions are carried out when incorrect data are found - omissions or inaccuracies in the data provided by the respondents.
|Data revision - practice|
No planned revisions of data. Unplanned revisions are made in case of detecting different types of errors - tehnical errors, discrepancies with previous periods.
|Data revision - average size|
|Timeliness and punctuality|
Data from respondents are received one month after the reporting semester. Analysis, verification and preparation of country representative aggregate average prices are carried out by the end of the third month following the reporting period.
|Time lag - first results|
3 months after the reporting period:
|Time lag - final results|
3 months after the reporting period:
Data are published accurately according to the Release Calendar (three months after the reporting period: for the first semester - at the end of September of the current year and for the second semester – at the end of March of the next year).
|Punctuality - delivery and publication|
60 days between the delivery/release date of data.
Target dates on which data are scheduled for delivery/release are as follow:
|Coherence and comparability|
|Comparability - geographical|
Data are representative at national level, as required by the methodology of calculation of prices for standard groups of household and final non-household customers (Regulation (EU) 2016/1952, Annex 1 and 2).
|Asymmetry for mirror flows statistics - coefficient|
|Comparability - over time|
Data in time series are calculated by same methodology and are comparable, as prices from the first semester of 2017 cover not only industrial end-users, but all final non-household customers.
|Length of comparable time series|
No break in time series.
|Coherence - cross domain|
|Coherence - sub annual and annual statistics|
|Coherence - National Accounts|
|Coherence - internal|
Annual prices are coherent with the semestrial prices.
|Accessibility and clarity|
The survey results are available to all users on the NSI website under the section Environment and Energy, theme Energy - Electricity and natural gas prices: https://www.nsi.bg/en/node/5033/electricity-and-natural-gas-prices, as well as in online Information System INFOSTAT, section Environment and Energy, theme Energy - Electricity and natural gas prices:
|Data tables - consultations|
Information service upon request according to the Rules for dissemination of statistical products and services.
|Metadata - consultations|
|Documentation on methodology|
Regulation (EU) 2016/1952, Annex 1 and Annex 2.
Compilers guide on European statistics on natural gas and electricity prices
|Metadata completeness – rate|
78.3% or 47 metadata elements provided of 60 metadata elements applicable.
Quality report according to Regulation (EC) No 2016/1952
|Cost and burden|
Costs related to the collection and production of statistics on electricity and natural gas prices are announced annually in the National Statistical Programme.
No specific surveys on the burden of respondents.
|Confidentiality - policy|
|Confidentiality – data treatment|
Published data do not allow identification of single consumers. Individual data on prices are not published (they are suppressed), following Art. 25 of the Law on Statistics. Publishing of individual data is made under Art. 26 of the Law on Statistics.