Hannover-Kronsberg a housing-area with very far going aspects of sustainability

The presentation: The Kronsberg-Housing-Area an overview Far going aspects of a sustainable development: Waste Energy Rainwater

The Kronsberg Settlement 1995 Start of development planning 1997 Construction starts on residential buildings (around 30 different developers) 2000 Completion of approx. 3,000 homes Reserve land to the north and south for further 3,000 homes Excellent transport connections to the city centre 9 km from the city centre

Kronsberg Settlement Approx. 80% of building land owned by the City Overall concept enforced through clauses in land sale contracts and planning permission contract

Kronsberg Settlement Approx. 50% subsidised housing 2,700 units in 3 – 5-storey apartment houses 300 2-storey private terraced houses

Waste

Dramatic reductions in waste quantities (1989 - 2002) Waste avoidance (- 380,000 t) Dumping of soil, building rubble, sewage sludge (- 340,000 t) Recycling, composting of organic waste (+ 72,000 t) Recycling of glass, paper, packaging and scrap metal (+ 41,700 t) Decrease in waste-to-disposal from c. 1,000,000 to 200,000 tonnes p.a.!

Great potential for commercial waste reduction

Result at Kronsberg: Household Waste Pre-sorting Approx. 30% reduction in waste volumes (City: 219 kg per household p.a., Kronsberg: 154 kg per household p.a.)

Result at Kronsberg: Construction Waste Preventive waste management planning on building sites Result at Kronsberg: 86% pre-sorting of waste and recyclables

Result at Kronsberg: Soil Management 700,000 m3 excavated soil re-used, making about 100,000 lorry journeys unnecessary and thus saving 1,200 tonnes of CO2 emissions

City of Hannover Waste Treatment Concept commercial waste construction waste household waste organics bulky waste sewage sludge street sweepings ca. 69,000 t/a ca. 1,000 t/a ca. 51,000 t/a ca. 38,000 t/a ca. 90,000t /a ca. 15,000 t/a ca. 16,000 t/a ca. 70,000 t/a composted ca. 5,000 ca. 215,000 t/a mechanical residual waste treatment ca. 100,000 ca. 100,000 ca. 15,000 ca. 100,000 t/a biological treatment since 2006 ca. 100,000 t/a waste to energy since 2005 ca. 5,000 ca. 35,000 ca. 70,000 ca. 25,000 ca. 3,000 compost ca. 35,000 t/a slag ca. 25,000 t/a hazardous waste landfill ca. 3,000 t/a recyclables ca. 20,000 t/a landfill ca. 70,000 t/a 1 1 1

Treatment Concept for Residual Waste 1/3 biological treatment (fermentation) 2/3 incineration Use of landfill gas at the central dump and methane from a waste fermentation plant (approx. 15,000 MWh/a)

Energy

Hannover - Climate Protection Region Since 1994: municipal climate protection programme, with a specialist unit in the city administration Since 2000: climate fund run by the municipal energy utility and the city council - 5 million € funding programme each year Since 2001: regional climate protection agency

Successes with Renewable Energy Within the city area: 466 registered solar thermal units, total area 4,500m² 209 solar electricity units, total 1,600 KWpel capacity Exploitation of the hydro-electric potential of Hannover’s river (1.38 MW rating) In the Hannover Region: Approx. 225 large wind turbines, which can meet the electricity needs of around 170,000 homes About 1,000 buildings a year retrofitted for energy efficiency

CO2 Reduction at Kronsberg CO2 reduction: 60%! With the windmills 80% CO2 emissions in % low energy house standard + cogeneration heating power plant (about - 20%) + electricity saving (-10%) + two wind turbine generators each 1.5 MW (-20%) (about -30%)

Optimised Insulation Walls: 15 - 20 cm Roofs: 18 - 25 cm Heating energy demand: Average 56 kWh/m2 and year

District Heating Decentral cogeneration heating plant Compulsary connection to the network Only 5% more expensive than new-build developments with district heating connections elsewhere in the city

Wind Energy Successful, and no protests from local citizens! Two MW-class wind turbine generators in the countryside meeting the electricity needs of 3,000 homes Successful, and no protests from local citizens!

The Next Step: Passive Houses Domestic electricity Ventilation electricity Hot water Heating from ... To End energy index kWh/ (m²a) over 90% reduction compared to old housing stock

Target met! Residents very satisfied 1998: pilot project of 32 Passive Houses at Kronsberg Energy consumption just 15 kWh/m2 p.a. Target met! Residents very satisfied

What makes a Passive House? Maximum insulation (40-45 cm in walls, 30 – 40 cm in the roof) Triple glazed reflective coating windows filled with inert gas Comfortable ventilation system with heat recovery Max. supplementary heating demand: 15 kWh / m² a Optimised solar gain Blower door test

‘In der Rehre’ planned development of 300 detached Passive Houses

Following completion of the new-build Kronsberg settlement, a major new pilot project: ‘Concerto’ Integrated EU project – ‘Energy saving in the building stock and use of renewable energies’

‘Concerto’ Aims 60-70% savings on end energy for heating Use of renewable energies wherever possible. Measures Energy efficient retrofitting of multi-occupancy houses owned by several Hannover housing associations (dating from 1950-1970) to a high energy efficiency standard Use of renewable energy by conversion from coal to biomass for the existing district heating network.

Rented apartment house to Passive House Standard: ‘Auf dem Hollen’, Hannover Modernisation in 2004

Rainwater Management

Worldwide, major flooding problems from increasing sealing of infiltration areas by development Factor 10 approach: Where possible, total retention and infiltration within the development area

Rainwater Concept at Kronsberg Natural water balance retained

Intelligent Rainwater Management Conventional construction paved and built-up surfaces Rainwater runs off into the sewers. Hannover future standard fewer sealed surfaces permeable surfaces on e.g. car parks groundwater infiltration alternative flood protection measures

(Mulden-Rigolen) Infiltration Trench Systems

Flat roofs Minimising built-up areas grassed wherever possible Minimising built-up areas Remarkable positive commitment by planners

Ponds Water as a design element in the inner courts Diverse planning and landscaping solutions Infiltration and evaporation

Thank you! Internet: www.hannover.de www.sibart.org (German, English, French & Spanish) www.hans-moenninghoff.de