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SECTOR: Holistic

COUNTRY: Denmark

BACKGROUND
Renewal of the Hedebygade Block is part of an ongoing renewal of Vesterbro, a central district of Copenhagen. It has been a working-class district since 1850 and one of the first town districts built outside the ramparts of the old city. The dawning age of industrialism made this expansion necessary. So far Vesterbro is a district consisting of buildings used for trade, industrial purposes and blocks of flats all mixed together.
Characteristic of the 1880s, the Hedebygade Block was very dense with both side and back houses. But unlike Nørrebro, another central district, Vesterbro didn't go through a total clearance with large demolition of houses. Instead scattered demolition and hollowing out of the blocks became the main procedure. This strategy was confirmed by an overall action plan for Vesterbro initiated by the Copenhagen City Council in 1989. Important statements of intent in this action plan were high-quality renewal, energy saving, urban ecology and public participation Thus in 1972 the City Council decided to hollow the Hedebygade Block.
In 1991 the block was pointed out as worthy of preservation and in 1993 a new municipal plan declared the Hedebygade Block to be a part of a larger urban renewal plan for the district. This plan stated that existing houses had to be preserved with regard to environment, architecture and social life.
The Urban Renewal Company (SBS) published a proposal for the renewal of Hedebygade Block in June 1995. Disagreements between the residents of the block and the municipality concerning the rents level and concerning flats being converted into one resulted in protest actions, so that a final decision on the renewal was not made until March 1996.

At that time environmentally considerations became more in focus, not least promoted by an Urban Ecology action Plan initiated by the former Ministry of Housing. Moreover a public support arrangement for urban renovation stressing the quality, productivity and resource consciousness, placed the Ministry in a central position.

On this background a co-operation arrangement between the Ministry and the Municipality of Copenhagen concerning the Hedebygade Block was confirmed. By this arrangement the Hedebygade Block renovation became an urban ecological demonstration project of high technological performance addressing competitive products and international exchange of knowledge. Dkk 40 m ( euro 5 m) was granted.

DEMONSTRATION PROJECT
The overall objectives of renovating the Hedebygade Block was:

• to establish a greater demonstration project in Copenhagen of ecological (environmentally sound) renovation
• to contribute to ecological solutions for renovation of old houses
• to demonstrate Danish capacity of ecological renovation
• to promote commercial utilisation of ecological solutions for urban renewal

Sixteen proposals were submitted by engineering and architects teams. Twlelve of these were selected for implementation, one 3 was later dropped. All projects, except of number 9 and 12 were connected to a specific building on the block. Each project dealt with different subjects, see the following paragraphs:

INDICATORS

1. Prism. Sunlight canalised into the building through the roof by use of a mirror (heliostat). Also inside and outside facade insulation and energy control have been effected in order to save energy.

2. Flora. Re-circulation of indoor air through plants and rootzones in order to clean the air and to save energy. Moreover cabinets chilled by means of cold air was installed.
3. Given up.
4. 'Green' Kitchen. Use of environmentally sound kitchen furniture, vertical hotbeds for growing and arrangement of kitchens in order to save water and energy.
5. Sun wall. Heat recovery by means of a heat exchanger, passive solar energy, insulation, low-emmission glazing and air type collectors on the roof.
6. Flexible facades. Covering facades and balconies with glazing elements combined with the use of solar cells (photovoltaics) and other kinds of plate elements.

7. Integrated ecological renewal. Addition of low energy facade element in order to extend existing kitchens, low-emission glazing, low-temperature central heating, ventilation with reclaiming of energy, individual metering of heat, electricity and water consumption, insulation, et cetera.
8. Sun in the urban renewal. Ventilated sun walls with integration of solar panels on transparent insulation, low emission glazing, low temperature central heating, integrated solar cells on the roof, ventilation with heat recovery, more sunlight in the apartments, individual metering of heat electricity and water consumption.
9. Waste sorting. Establishment of cabins for environmntally sound sorting of waste on the block for sorting in eight fractions at least, composition of information material and education of residents and caretakers of the whole block.
10. Shared courtyard and community house. Ecologically arranged courtyard for recreational purposes, with rainwater collection, cabins for waste sorting and environmentally friendly planting. The community house, located in the middle of the courtyard, is fitted out with a community room, kitchen facilities and a common laundry with rainwater etc.

11. House end project. Establishing different kinds of insulation in combination with solar cells and plant trellises.
12. Measurement of consumption. Individual measurement of the heat, electricity and water consumption in order to save energy and ground water.

INDICATORS
Following the concept of Eco-accounting (Environmentally accounting) improved by the Danish Builiding and Urban Research, five indicators for the extent of sustainability are used. These 'urban ecology indicators' are heat consumption, electricity consumption, water consumption, waste production and CO2 emission. All indicators are based on annual accounting (y) and related to the amount of residents' (p). An additional indicator makes up the heat account in relation to the area being heated.

Indicators	Unit	Hedebygade	Versterbro	Denmark
Heat consumption	MWh/p. y	5		6.9
Heat consumption (Additional indicator)	MW/h/100m2.y	12		11.5
Electricity consumption	KWh/p.y	900		1563
Water consumption	m3/ p.y	42		49.6
Waste production	Kg/p.y			444
CO2 emission	Metric ton/p.y	1.1		3.2

Table 1. Indicators made up by usingf the Danish concept for Eco-accounting. Source: Green Accounting 2001 for the Hedebygade Block and the Statistics Denmark concerning the average consumption in Denmark. Data on Vesterbro follows. Data on Hedebygade Block are provisional figures based on two buildings only.

The total opening of the urban renewal project showing that all projects of the Hedebygade Block renovation has been finished, took place on 7 June 2002.

EVALUATION
The evaluation made by Danish Building and Urban Research will finish in 2003, for which reason the following facts are based on early conclusions of an ongoing evaluation. However, it is already now possible to present some provisional conclusions of the residents' satisfaction of the project, on the level of consumption, on the architectural standard, and finally on the urban renewal process.

A questionnaire completed in 2002 documents an increasing interest for urban ecology among the residents, but at the same time shows disappointment about the urban renewal process. Thus the urban ecological initiatives set in motion with the urban renewal do not match the expectations of the residents. The residents do not feel comfortable with the level of information and they feel ignored in the planning process.

The first eco-accounts drawn up confirm that the renewed houses have much smaller need for heating than in similar houses being renewed in a traditional way. Nevertheless, the consumption of energy for heating is still higher than the budgets based on calculations made beforehand.
The electricity consumption is at the same level as that of the other blocks, whereas the water consumption is lower (see Table 1). At this time an information activity has been initiated that centres a dialogue on the measurement of heat, electricity and water consumption in every single apartment and presents quarterly eco-accounts. On this background, It is anticipated that further reductions will appear.

Professionals have already praised the architectural standard. But also the residents do feel pride of their renewed block, the new facades, the newly built community house and their changed courtyard. In spite of modern design and new materials, the architectural expression is broadly accepted. Also visitors from abroad have praised the urban design. Nevertheless, critical voices fasten on the fact that money has been spent on showing urban ecology rather than urban ecology itself.

The urban renewal process has been of long duration. It was decided to renovate the Hedebygade Block in June 1995, but the renewal process had actually started in 1972, when the City Council decided to hollow out the Hedebygade Block. Since then, proposals made by the City Council, the urban renewal company and the residents in turn have made several. In an urban district where elderly people and young students predominate, thirty years run-up is too much. People loose patience, get tired or move to another place. The urban ecology aspect and the prospect of an ecologically sound apartment made young people stay. Still peoples' patience was severely tried.

BENCHMARK DATA
Benchmark data are the average consumption of energy and water and the average production of waste and emission of CO2 in Vesterbro and Denmark respectively. See Table 1.

DRIVERS
The Copenhagen Municipality, The Ministry and several consulting architect firms and engineering companies have all been the driving forces. The Hedebygade Block was chosen, because of active and interested residents. The majority of houses had to be renovated, and the municipality had several of them at it's disposal. Focus was on glazing and exploitation of solar energy and a need to demonstrate full scale testing of 'alternative' technologies.

LESSONS LEARNT
Already now much can be learned from the Hedebygade Block case, not least concerning sustainable building and urban ecology. The point of view is decisive when the Hedebygade Block is evaluated: Is it a project for renovating the Hedebygade Block in an Urban ecological way a project testing 'alternative' technologies on residents terms, or is it a show case for the Danish High technology industry? Probably both aspects are imbedded. Put strictly, there is a difference between Urban ecology and environmentally management (Jensen, 1994), taking into account that urban ecology is based on simple technology and grass-root activities whereas environmentally management is based on advanced technology and civic involvement. While several residents replied to the first the City Council and the urban renewal company replied to the second. The final, but perhaps most important lesson, learnt, concerns duration. Regardless of the principle of renovation, it is important for the support of, and the dialog with, the residents that the planning period and the time for implementation does not spread over more than three years.

APPLICATION
The technical constructions innovated for the Hedebygade Block has already spread into other parts of new building and urban renewal.

TRANSFERABILITY
Local conditions have to be taken into consideration, when transferability is discussed. However, it seems that conditions in Southern Europe could be even more favourable for application of solar cells, heat collectors and heliostats.

IMPACT ON SUSTAINABILITY AREAS
The environmentally impact is high, if placed on the right locality. The social impact will be high too if carried out in a social context of urban ecology, i.e. bottom-up activity, small scale and simple technology. Otherwise the social impact, like in Hedebygade, will be medium. The economic impact can be high too. But opposite bottom-up activities, top-down activities are needed in that case.

PROJECT CONTACT
Phil.Dr. Senior Researcher Ole Michael Jensen Danish Building and Urban Research Housing and Urban Research Division P.O. Box 119 DK-2967 Hørsholm Tel: + 45 86 55 33; fax: +45 86 55 94; e-mail: omj@by-og-byg.dk

REFERENCES

• Elle, Morten (1996): lntegrated Solutions in Urban Ecology- Dream or Reality, in 'The European City -Sustaining Urban Quality', Ministry of Environment and Energy, Copenhagen.
• Jensen, Niels-Arne et al. (1998): Byøkologiske Løsninger, Ministry of Housing, Copenhagen.
• Jensen, Ole Michael (1994): Ecological building - or just environmentally sound planning (Økologisk byggeri - eller blot miljørigtig projektering) In: Arkitektur DK, nr. 7 1994. s 353-367.
• SBS (Urban Renewal Company) (1998): Byøkologiprojektet i Hedebygadekarreen, København (The Urban Renewal Project in Hedebygade Block, Copenhagen). SBS.