Fuel wood consumption in Austria Household survey Quality standard Conversion factors

Transcription

1 Manfred Gollner Directorate Spatial Statistics Paris 11 June 2012 Fuel wood consumption in Austria Household survey Quality standard Conversion factors We provide information

2 Household survey characteristics Voluntary survey attached to the obligatory Labour Force Survey of Statistics Austria Observation units: households at their main residence All households receive a letter to prepare the latest annual bills for electricity, gas, district heating and other fuels Sample size: 22500, response rate is in a range of 50% to 75% (at least 8500 valid responses) performed since 1975 in irregular, perennial periods; since 2004 in biennial periods before 2004: "face to face" interviews, since 2004 "computer assisted telephone interviews" (CATI) Grossing up occurs with size and age of the dwelling, number of gas meters, number of installed wood chip and pellet boilers attributed to households slide 2 15 June 2012

3 Questionnaire slide 3 15 June 2012

4 Calculation of the Final Energy Consumption (FEC) and shares of the end use category Plausibility checks and validation on single data level by calculation of amount/cost pairs Reported FEC on household level: total of all consumed fuel amounts Assumed FEC on household level: average consumption for space heating, water heating and cooking plausibility checks (tolerance ±50%) Grossing up and aggregation of fuel consumption and end use category for Austria and the federal states on NUTS 2 level Determination of fuel specific use for space heating, water heating, cooking and other use of electricity slide 4 15 June 2012

5 Data validation in detail For all fuels and end use categories: Unit conversion with conversion factors Correction of unrealistic high or low amounts and prices (with average values and upper limits) Correction of impossible combinations of fuels and purpose (e.g. district heat or solar thermal heat for cooking) In case of missing amount OR price: calculation with average amounts or market prices In case of missing amount AND price: e.g. if wood fuel is free of charge, or bills got lost calculation with average amounts depending on the purpose, the fuel and the number of persons in the household or per m 2 living space main fuel for space heating has a share of 70% compared to additional fuels for space heating slide 5 15 June 2012

6 Conversion factors Conversion factors for fuels reported in various physical units Fuel [Unit] kg l stere/bcm m³ kwh Cent/unit GJ/unit Natural gas [kwh] 0, ,1 0,0036 Natural gas [m³] 1 10,8 66,3 0,0389 Fuel wood [kg] 1 0,0023 4,0 13,9 0,0143 Fuel wood [stere] ,3 6000,0 6,1680 Wood chips [kg] 1 0,0039 3,2 5,5 0,0114 Wood chips [bcm] ,2 1416,7 2,9169 Fuel oil [kg] 1 1,189 11,9 85,6 0,0428 Fuel oil [l] 0, ,0 72,0 0,0360 LPG [kg] 1 1,724 12,8 137,9 0,046 LPG [l] 0,58 1 7,4 80,0 0, stere = 1 m³ of stacked wood pieces with a length of about 1 m 1 bulk cubic meter (bcm) = 1 m³ of loosely poured wood slide 6 15 June 2012

7 Upper limits Upper limits of annual energy consumption with corresponding costs Fuel [phys. Unit] Amount Costs [ ] Hard coal [kg] Lignite [kg] Browncoal briquettes [kg] Coke [kg] Fuel wood [kg] Pellets [kg] Wood briquettes [kg] Wood chips [kg] Fuel oil [kg] LPG [kg] Non interruptible electricity [kwh] Interruptible electricity [kwh] Natural gas [kwh] District heating [kwh] Central heating (fuel unknown) [kwh] slide 7 15 June 2012

8 Water heating and cooking Average values of annual energy consumption Nr. of persons in the Energy demand End use category household [ kwh ] [ GJ ] Water heating 1 per Person ,32 Cooking ² ,35 Cooking ² ,71 Cooking ² ,96 Cooking ² ,57 Cooking ² 5 and more 883 3,18 1 assumed as linear function; 2 assumed as a non linear function slide 8 15 June 2012

9 Space heating Average annual energy demand for space heating per m² in dependence on the building size and age Detached / semidetached houses Apartment houses Fuel Construction period Construction period till after 1990 till after 1990 Hard coal [kg] 29,8 21,3 12,5 23,4 17,0 12,3 Lignite [kg] 86,2 61,7 36,1 67,7 49,1 35,7 Browncoal briquettes [kg] 43,3 31,0 18,1 34,0 24,6 17,9 Coke [kg] 29,6 21,2 12,4 23,2 16,9 12,3 Fuel wood [kg] 58,3 41,7 24,4 45,7 33,2 24,1 Pellets [kg] 48,3 34,6 20,2 37,9 27,5 20,0 Wood briquettes [kg] 48,7 34,9 20,4 38,2 27,7 20,2 Wood chips [kg] 73,2 52,4 30,6 57,4 41,6 30,3 Fuel oil [kg] 19,5 14,0 8,2 15,3 11,1 8,1 LPG [kg] 18,2 13,0 7,6 14,2 10,3 7,5 Heat pumps [kwh] 154,7 110,7 64,7 121,3 88,0 64,0 slide 9 15 June 2012

10 Example: data validation in case of missing amount AND price Household: 4 Persons, in a flat with 90 m², constructed in the year 2000, calorific value of firewood = 14,31 MJ/kg Water heating: 4,32 x 4 = 17,28 GJ fire wood: 17280/14,31 = 1208 kg additional fuels: hard coal and charcoal briquettes fire wood: 1207,6/3 = 403 kg Cooking: 2,57 GJ fire wood: 2570/14,31 = 180 kg additional fuels: hard coal and charcoal briquettes fire wood: 179,6/3 = 60 kg Space heating: 24,1 kg/m² x 90 m² = 2169 kg firewood as main fuel, additional fuels: hard coal and charcoal briquettes fire wood = 2169 * 0,7 = 1518 kg Total = 1981 kg Shares: water heating: 20%, cooking: 3%, space heating: 77% slide June 2012

11 The quality standard of wood fuels should support the implementation of reliable statistics on wood fuel consumption in households Statistics on wood fuel is tricky, because of inhomogeneous matter (different wood species and volume to mass conversion factors, ) special market situation (non purchased quantities, informal or 'grey' markets, ) inexperienced respondents, missing bills, different units (kg, stere, m³, water content vs. moisture),... focuses on consumer based surveys e.g. face to face or telephone interviews In case of low importance of wood fuel consumption in households expert estimates and modelling could be acceptable alternatives slide June 2012

12 Important steps to ensure reliable information Consumption surveys with representative samples in adequate frequencies Experienced interviewers, self explanatory questionnaires Defined regional wood fuel mix (most frequent wood species) Average mass by volume units based on wood fuel mixes Average calorific values based on the wood fuel mixes and water contents Default values for consumption by purpose (space heating, water heating, cooking) for data validation Well documented data validation procedure Availability of time series (at least 3 surveys to get an impression on data reliability) slide June 2012

13 Energy content The gross calorific value (GCV) of absolute dry wood is nearly on the same level for all wood species only a minor difference between coniferous (19 MJ/kg) and deciduous (18 MJ/kg) wood, due to a higher resin and lignin content The energy content of wood is much more dependent on the water content than on the wood species there is a difference between water content and moisture Water content w (%): w = (Wf-Wd)/Wf Moisture m (%): m = (Wf-Wd)/Wd Wf fresh weight, Wd dry weight If you buy 1000 kg of fresh cut fuel wood with 55% w Wd = Wf*(1-w) = 1000*0,45 = 450 kg dry weight 55% m Wd = Wf/(m+1) = 1000/1,55 = 645 kg dry weight Difference of 195 kg (20%)! slide June 2012

14 Water content and calorific value MJ/kg ,3 14,7 12, ,2 Net calorific value (NCVw) of fuel wood wood pellets fuel wood, stored two or more seasons (+104%) fuel wood, stored one season (+74%) fresh cut wood *) ( =100%) water content (%) *) depending on wood species, age and season slide June 2012

15 Conversion factors Compiled by the Austrian Energy Agency in co operation with experts from: Universities and other research institutions (e.g. Biomass Logistics Technology Wieselburg), Austrian Standards Institute, Austrian Chamber of Agriculture, wood and wood products industries, pulp and paper industries This factors could be used, if no national standards are established! More detailed information on different wood fuel assortments: link slide June 2012

16 Please address queries to: Manfred Gollner Contact information: Guglgasse 13, 1110 Vienna phone: +43 (1) fax: +43 (1) Thank you for your attention slide June 2012