EffCoBuild. Energy Survey and Saving Potentials in the Building Sector

Transcription

1 EffCoBuild Energy Survey and Saving Potentials in the Building Sector City of Eggesin Berliner Energieagentur GmbH Französische Str Berlin Telefon Telefax office@berliner-e-agentur.de compiled by Dipl.- Ing. Architekt Frank W. Lipphardt Cand. Wirt. -Ing. Sascha Brandt Dipl.- Ing. Claudia Alt Projekt-Nr /02/07

2 Inhalt 1 Conclusion 3 2 Conceptual Formulation 3 3 The City of Eggesin Geography Demography Energy Supply Structures 5 4 Residential Buildings General Residential Building Stock Individual Owned Building Stock Building Stock Structures Energetic Quality Fehler! Textmarke nicht definiert. 4.3 Communal Managed Building Stock Building Stock Structures Energetic Quality Energy Supply Structures Individual Owned Building Stock Communal Owned Building Stock 15 5 Public Buildings 16 6 Appendix 23 Table Of Figures 23 Berliner Energieagentur GmbH Seite 2

3 1 Conclusion 2 Conceptual Formulation It is planned to investigate the total energy demand of the city of Eggesin as well as the amount of energy consumed by the buildings. The building stock will be classified by its condition regarding the energy demand, and for each group of building the saving potential will be estimated. The estimation will be orientated at technical standard values and experience values of energy refurbishments of buildings in the region. The sum of the saving potentials in all building groups results in the total energy saving potential of the community. 3 The City of Eggesin 3.1 Geography Eggesin is situated in the north-east of the Federal Republic of Germany near the Baltic sea and the Polish border. This location of Eggesin causes structural problems, because until now it is still economically cut off of the polish back country and the nearest large City Stettin, because of a still shut border crossing. The region is characterized by agriculture on the one side and few industries on the other side. Picture 3-1: Geographical position of Eggesin in Germany Berliner Energieagentur GmbH Seite 3

4 The town by itself exhibits strongly fragmented structure (see figure below). Especially due to the post war construction activities in the German Democratic Republic Eggesin never developed a real city centre. In addition the town is burdened by large, in most parts deserted military bases due to the need to convert them into facilities of use or to demolish them. Picture 3-2: Map of Eggesin 3.2 Demography The town of Eggesin is a small town with now about inhabitants. After the Federal Armed Forces had closed their barracks in the beginning of this decade, the population has decreased drastically. The following figure shows the development of the population of Eggesin (except for military staff). Eggesin Population Inhabitants Year figure 1: development of the population in Eggesin Berliner Energieagentur GmbH Seite 4

5 It is anticipated that the population will decrease further in the future caused by general migration from smaller to bigger towns and from East Germany to West Germany. 3.3 Energy Supply Structures Beside a municipal owned district heating grid, that provides the majority of the communal managed apartments and some public buildings with heat, Eggesin is supplied with gas, liquid gas and electricity by only one regional supplier E.ON edis. Fuel oil, that is also used, is provided by private dealers. 4 Source of energy data GWZ 1995 (Building and dwelling counting 1995) ISEK 2005, Eggesin (Integrated Concept of municipal development) Questionaire of energy data City of Eggesin (public buildings) 5 Residential Buildings Eggesin has quite an eventful history. In 1995 there have been still apartments in total in town. Due to the shutdown of the military base that came along with a loss of jobs and shrinking population numbers there was a need to compensate the lower demand for apartments. Therefore the town deconstructed several buildings with 482 apartments in total until Eggesin still exhibits an oversupply of living space. Hence an ongoing process of deconstruction can be expected. It becomes clear that Eggesin features special structural and demographic conditions that have to be taken into account in a comprehensive analyses regarding energy efficiency, especially in an energy saving potential examination which includes long-term energy efficiency measures. 5.1 General Residential Building Stock The residential building stock in Eggesin is characterized by three main phases of development. Before World War 2 Eggesin exhibited typical small town structures with a mix of one and two family houses and small multi family residences. After the war Eggesin became one of the main garrison towns in the former German Democratic Republic. New jobs came in town along with the military and the population rose fast. In order to meet the growing demand for apartments big multifamily residences have been erected. The third phase happened after the two German states reunified. This time was characterized by moderate new construction activities. Mainly one and two family houses and small multifamily houses have been erected in this period. Berliner Energieagentur GmbH Seite 5

6 age structure of the residential building stock year of construct nach 1995 apartments buildings numbers of build./apartm. figure 2: age structure of the entire residential building stock (according to GWZ 1995, ISEK 2005) The figure above illustrates the age structure of the entire residential building stock in Eggesin. The number of apartments built in a period gives an idea of the seize of the buildings that were erected in different decades. The seize structure of the entire residential building stock in Eggesin is demonstrated by the next graphic. One and two family houses but in particular one family houses represent the biggest part of the residential building stock. Although multifamily residences are in terms of numbers by far the minority, they have in total more apartments than one and two family houses together. This is particularly due to the seize of those multifamily residences that were erected in the 70s and 80s of the last century. They have in general more than 10 apartments per building. Berliner Energieagentur GmbH Seite 6

7 seize structure of the residential building stock number of build./apartm one/two fam.res. multifam.res. 3-6 WE multifam. res WE multifam.res WE apartments buildings seize figure 3: seize structure of the residential building stock (according to GWZ 1995, ISEK 2005) In order to create effective strategies and campaigns that support to overcome investment barriers regarding energy efficiency measure, it is necessary to identify the main stakeholders in the housing business. The following graphic delivers insight into the property structures of the residential building stock. property structures of buildings municipilaty 21% others 8% individual 71% figure 4: property structures of the residential building stock in Eggesin (updated on base of GWZ 2005) The figure above makes clear that the majority of buildings in Eggesin is owned by individuals. That is not surprising as one and two family houses represent the by far biggest part of the building stock. Berliner Energieagentur GmbH Seite 7

8 Even though the city of Eggesin owns only about 21% of the total residential building stock, its buildings represent almost 50% of all apartments in the municipality. To sum up, individuals and the city of Eggesin are the main actors in the housing industry. Therefore it is sufficient to look at the individual and communal owned building stock in order to examine the energetic quality of the entire building stock in Eggesin. About 8% of all buildings are owned by others like another housing society, Churches, etc. However, considering the size of those buildings, respectively the number of apartments per building, legal entities and others are only minor players in the housing business. 5.2 Questionnaire of energy data To estimate the energy consumption for the residential buildings, a questionnaire of energy data was developed for all project partners. In April 2006, 200 exemplars of the questionnaire were distributed by the city of Eggesin. 66 of them were completed by the municipal housing company for its completely building stock; the reflux of privat building owners however was poor with only 20 exemplars. 5.3 Individual Owned Building Stock Evaluation of the questionnaire specific heat energy consumption unrenovated partly renovated completely renovated kwh/m²a year of construction figure 5: specific heat energy consumption of the private residential buildings (questionnaire) Berliner Energieagentur GmbH Seite 8

9 5.3.2 Building Stock Structures It is possible to say that one and two family houses in Eggesin don t exhibit distinct attitudes. That means, they have been erected more or less constantly, mostly during the last century with increasing energetic quality in particular during the last two decades. In addition many house owners have modernized their home and have combined necessary modernization measures with energy efficiency improvements. However, the extent of those improvements lies between such a big range, depending on the owner, that it is not possible to make general statements. 5.4 Communal Managed Building Stock Eggesin itself owns 1053 apartments. In addition it administers another 162 apartments, thus in total about 45% of the 2672 in the community. Four different building types represent the communal managed building stock. The following pictures show an old building in brick construction from the turn of the century, a typical post war building from the 50s, a multifamily building made with precast concrete slabs and a relatively new apartment building also erected with bricks. Berliner Energieagentur GmbH Seite 9

10 5.4.1 Building Stock Structures The communal managed building stock is dominated by buildings that have been erected in the 50s, the 70s and in the 90s (see figure 5). The city itself as the biggest initiator of new construction in Eggesin has tried to react on changes in the demand for living space during the time of socialism as much as today. The post war construction in the 50s and the erection of huge multifamily residences in the 70s and 80s was due to the population growth in Eggesin, whereas the construction activities in the 90s had its origin in an increasing demand for modern living space after the reunification of Germany. Hence even with decreasing population numbers and a continuously shrinking demand in the apartment market, new construction had been necessary. construction year structur number of buildings today year of construction figure 6: construction year structure of the municipal operated building stock (questionnaire) As already mentioned, the communal operated building stock is dominated by multifamily residences (see figure 6). There is only one two-family building in the entire stock. More than 50% of the apartment building stock is represented by buildings with more than 10 apartments per building. Recapitulating, the communal administered building stock is characterized by a low number of relatively huge apartment buildings. Berliner Energieagentur GmbH Seite 10

11 seize structure number of buildings units 3-10 units >10 unis number of apartments figure 7: seize structure of the municipal managed building stock (questionnaire) The construction type of the apartment buildings is determined by the year of their construction. For those buildings that have been erected until the end of the 60s and after 1990 the brick construction is typical, whereas all apartment houses that were built up in the 70s and 80s are made with precast concrete slabs, the so called industrial construction. Since the latter construction type is seen as the less preservable one and was characterized by high vacancy in the 90s, the deconstruction of apartment buildings in Eggesin was focused on those buildings. The following figure illustrates the distribution of the two construction types in the communal managed building stock. Berliner Energieagentur GmbH Seite 11

12 construction typ of buildings 39% 61% industrial construction brick construction figure 8: construction types in the communal managed building stock (questionnaire) The majority of industrial constructed buildings that has not been deconstructed was modernized in the 90s along with comprehensive energy efficiency measures like the insulation of external walls and the replacement of all windows with new efficient ones. Also all other apartment buildings in the municipal managed building stock like the older brick buildings have been updated in accordance with the then generalities regarding energy efficiency and emission standards. Only three industrial constructed buildings are still unimproved, since a need for cheap living space has been identified that prohibit both the deconstruction and the modernization of those buildings. Figure 8 shows that with the beginning in 1995 modernization activities in the municipal administrated building stock had its peak in 1998 and came to an end in 2000 with the completion of the building stock modernization. The refurbishment has been necessary, in order to assure a profitable business in the future. Berliner Energieagentur GmbH Seite 12

13 building modernisation activities 25 number of buildings year figure 9: modernisation activities in the communal managed building stock (questionnaire) Since the building stock of the municipality is almost completely modernized, the realization of further measures to improve the energy efficiency and in particular long-term measures seems to be unlikely Energetic Quality In order to assess the energy efficiency of the different building types within the municipal managed building stock, their specific heat consumption has to be examined. The following graphic shows the specific energy consumption of every single building. Berliner Energieagentur GmbH Seite 13

14 300 specific heat energy consumption of municipal residential houses kwh/m²a year of construction figure 10: specific heat energy consumption of the communal managed apartment buildings (questionnaire) Apparently there is a trend towards lower heat energy consumption along with the construction year of the buildings. However, only a few apartment buildings reach the energetic quality standards of the German Energy Saving Directive (EnEV) for new apartment buildings. Even though also all buildings that have been erected before 1960 were improved in terms of energy efficiency, their heat energy consumption is still way higher than that of younger buildings, partly even twice that high. Those buildings still exhibit additional energy saving potential. Interestingly modernized industrial constructed buildings, although older, don t exhibit higher heat energy consumption figures than those buildings that have been built up in the 90s. It is likely that the more cost aware renters of those apartment buildings are one part of the reason for this phenomenon. In Addition, the big industrial constructed buildings exhibit a quite compact structure, which is an advantage for energy efficiency purposes. However, the figures document that refurbished industrial constructed buildings can be as energy efficient as new buildings. 5.5 Energy Supply Structures In addition to the energetic quality of buildings, the heat energy provision is crucial in an energy efficiency assessment of the community Individual Owned Building Stock Auswertung der Marktanalyse Berliner Energieagentur GmbH Seite 14

15 One and Two family houses are characterized by a mixed heat supply structure. For the most part natural gas and heating oil are used in that part of the building stock in Eggesin. In addition many homes are equipped with stove that use either coal or wood and with electrical heaters Communal Owned Building Stock By contrast the apartment buildings that are managed by the municipality are provisioned by a district heating grid or by natural gas fired central heating. The district heating grid that provides heat also for some public buildings is mainly supplied by a wood ship fired district heating plant. The following graphic illustrates the heat energy supply structure of the communal administered building stock. heating supply structure (by consumed energy) 1% 34% heating oil natural gas district heating 65% figure 11: heating supply structure in the communal managed building stock (questionnaire) Additionally to this innovative heating plant and a small oil fired block heat and power plant, the city of Eggesin plans to build a new block heat and power plant fired with palm oil from Asia. This new plant shell enable the city to generate electricity that its public buildings consume. This supply concept is supposed to reduce the energy cost of the municipality compared to the electricity provision by the regional utility. Berliner Energieagentur GmbH Seite 15

16 6 Public Buildings Beside a number of apartment buildings that are managed by the city, Eggesin administers a number of public buildings: city council building elementary school secondary school vocational school with gymnasium recreational centre library fire department civil protection building building yard. However the vocational school is for the most administered by the district of Uecker-Randow. The following pictures show some of the public buildings. Recreational centre for pupil (source: Berliner Energieagentur GmbH Seite 16

17 Fire department (source: City council building (source: Elementary school (source: Berliner Energieagentur GmbH Seite 17

18 Secondary school (source: Vocational school ( The public building stock in Eggesin is like the residential building stock represented by old and new brick constructed and industrial constructed buildings. Figure 11 gives an overview of the energy consumption of all public buildings over the year 2005 in Eggesin. Berliner Energieagentur GmbH Seite 18

19 6.1.1 Energetic Quality of the public buildings building area (m²) consumption of electricity (kwh) specific consumption (kwh/m²) heat energy supply consumption of heat energy (kwh) specific consumption (kwh/m²) city council district heating vocational school district heating gymnasium 663 district heating secondary school oil-fired central heating elementary school oil-fired central heating recreational centre oil-fired central heating library district heating fire department natural gas-fired central heating civil protection natural gas-fired central heating building yard district heating Summe table 6-1: energy consumption of public buildings in Eggesin in 2005 (source: city of Eggesin) Beside the heat supply by the district heating grid, some buildings are provisioned by oil-fired or natural-gas fired central heating. The oil-fired boiler in the elementary school will be replaced by a natural gas-fired one in the near future. It is likely that this will happen to other oil-fired boilers as well. consumption of heat energy civil protection building fire department building yard city council recreational centre library vocational school elementary school gymnasium secondary school figure 12: proportional heat energy consumption of public buildings in Eggesin (source: city of Eggesin) The figure above illustrates the proportional heat energy consumption of the single public building in comparison with the total heat consumption of all public buildings. It becomes apparent that the city council building and the three schools are the major consumer of heat energy. The other 5 public buildings in Eggesin do not even represent 25% of the total heat energy consumption. Berliner Energieagentur GmbH Seite 19

20 consumption of electricity civil protection building fire department recreational centre library building yard city council elementary school secondary school vocational school with gymnasium figure 13: proportional electricity consumption of public buildings in Eggesin (source: city of Eggesin) The electricity consumption of public buildings shows almost the same situation (see figure 13). Again, the city council building and the three schools are the biggest consumer. In order to assess the energy consumption figures, it is necessary to compare them with reference values. Such figures for non-residential buildings exist in the German Energy Saving Directive (see figure below). building reference value for heat energy consumtion (kwh/m²a) reference value for electricity consumption (kwh/m²a) city council vocational school gymnasium secondary school elementary school recreational centre library fire department civil protection building yard figure 14: reference values for non-residential buildings (source: Entwurf vom der Richtlinie für Energieverbrauchskennwerte Nichtwohngebäude) These figures reflect the average specific consumption of different non-residential building types in Germany and thus allow a sensible comparison. Berliner Energieagentur GmbH Seite 20

21 kwh/m²a city council heat energy consumption in comparison with reference values vocational school gymnasium secondary school elementary school recreational centre library fire department civil protection building building yard real consumption reference consumption figure 15: heat energy consumption of public buildings in comparison with reference values (source: city of Eggesin) Assessing the figures in detail (see figure 14) the relatively high heat energy consumption of the city council building and the recreational centre become noticeable as much as the ones of the library and the building yard. However, the latter have to be relativized, since the library building is also used for a number of other purposes and the building yard is in general difficult to compare due to its heterogeneous composition of open and closed halls. The same is true for the fire department and the civil protection building. The result of the comparison with reference values seems to be quite good, but that does not necessarily mean that the buildings meet very high energetic quality standards. It is essential to analyze those buildings individually, since their use intensity can not be expected to be a fix value as it is expected in a comparison with reference values. Apparently those comparisons might exhibit a bigger issue when it is necessary to work with reference values and benchmarks, especially in the assessment of nonresidential buildings. Berliner Energieagentur GmbH Seite 21

22 specific electricity consumption in comparison with reference values 45,00 40,00 35,00 kwh/m²a 30,00 25,00 20,00 15,00 10,00 5,00 0,00 city council vocational school with gymnasium secondary school elementary school recreational centre library fire department civil protection building building yard real consumption reference consumption figure 16: electricity consumption of public buildings in comparison with reference values Examining the electricity consumption of public buildings, the city council building and the recreational centre stand out again with relatively high specific consumption figures as much as the vocational school. The assessment of the last 4 buildings, the library, the fire department, the civil protection building and the building yard is again only qualified possible. Berliner Energieagentur GmbH Seite 22

23 7 Appendix Table of Figures figure 1: development of the population in Eggesin... 4 figure 2: age structure of the entire residential building stock (according to GWZ 1995, ISEK 2005)...6 figure 3: seize structure of the residential building stock (according to GWZ 1995, ISEK 2005)... 7 figure 4: property structures of the residential building stock in Eggesin (updated on base of GWZ 2005) 7 figure 9: specific heat energy consumption of the private residential buildings (questionnaire)...8 figure 5: construction year structure of the municipal operated building stock (questionnaire) figure 6: seize structure of the municipal managed building stock (questionnaire)...11 figure 7: construction types in the communal managed building stock (questionnaire) figure 8: modernisation activities in the communal managed building stock (questionnaire)...13 figure 9: specific heat energy consumption of the communal managed apartment buildings (questionnaire) figure 10: heating supply structure in the communal managed building stock (questionnaire)...15 figure 12: proportional heat energy consumption of public buildings in Eggesin (source: city of Eggesin) figure 13: proportional electricity consumption of public buildings in Eggesin (source: city of Eggesin) 20 figure 14: reference values for non-residential buildings (source: Entwurf vom der Richtlinie für Energieverbrauchskennwerte Nichtwohngebäude)...20 figure 15: heat energy consumption of public buildings in comparison with reference values (source: city of Eggesin) figure 16: electricity consumption of public buildings in comparison with reference values Berliner Energieagentur GmbH Seite 23