City Cell Prototype

City Cell Prototype

Climate change adaptation

Project description

photos by Boys Play Nice

CITY CELL PROTOTYPE Research: NEXT Institute Project: KOGAA studio Client: Věřejná zeleň města Brna / Public Greenery of the city of Brno Co-ordination: City of Brno Photo: Boys Play Nice

INDEX

City Cell is a prototype for testing adaptation strategies for extreme climate conditions such as droughts, heatwaves or torrential downpours.

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Context

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Principle

9

Specifications

11

Data

3

Joštova street

Malinovského Sq. City Cell Prototype

Náměstí svobody

Dominikánské Sq.

Benešova street Zelný trh Main train station

Brno city center map Problematic areas compared with a heat map (aerial surface-heat mapping from 2015) source: gis6.brno.cz/mapa/teplotni-mapa

Gallery Vaňkovka

ÚAN 4

CONTEXT

CLIMATE CHANGE Climate change causes extreme climate conditions such as droughts, heatwaves or torrential downpours. In addition, these extremes are going to be more severe and frequent. Both urban and natural landscape are vulnarable to its consequences. The city of Brno has prepared a climate change adaptation strategy, which, besides other things, states:

30 °C Untill 2100, the average number of tropical days can increase from the current 12 up to 42.

4x Untill 2100, the average number of heatwaves may increase 4 times.

The frequency of torrential downpours is going to increase.

The strategy also states Brno is not sufficiently prepared for the consequences of extreme climate conditions. Many parts of the city consist of paved surfaces, which contribute to bad microclimate during hot summer temperatures.

In addition, paved surfaces cannot retain rainwater, which is drained through a unified sewage system.

As a result, potential torrential downpours can overflood and damage sewage infrastructure.

ADAPTATION MEASURES Cities can prepare for climate change with so-called adaptation measures, which decrease climate change impact on citizens and infrastructure. They can be both technical (e.g. rainwater collection containers) or natural (ponds, green roofs, green walls, rain gardens etc.)

PROJECT DESCRIPTION The City Cell project directly follows up on Brno’s adaptation strategy with a prototype of a specific measure, which combines natural processes and modern technology.

PROJECT GOALS Adaptation measures are a relatively new concept, so there is little practical experience to draw from. The aim of the project is to create a functional prototype, a pop-up installation, which will test relevant materials and technologies for future permanent adaptation measures. Another important aspect of the prototype is public awareness.

CONTEXT Malinovského square was chosen as site for the prototype, because it is very vulnerable to extreme climate conditions.

Apart for a few trees, the square largely consists of paved surfaces and does not offer any elements for microclimate improvement. In addition, the trees are not doing well and need to be maintained often. The whole square is drained through a unified sewage system, which does not enable rainwater retention or accumulation.

USE The prototype is designed as urban furniture, so it provides public interaction and explaination of the problematic.

* data from the chart are from: Zásady pro rozvoj adaptací na změnu klimatu ve městě Brně. * a heat wave is defined as three or more consecutive days with Tmax >30 °C * data are from RCP 8.5 script, which estimates global temperature to rise by 2.0 °C during 2046–2065 and by 3.7 °C during 2081–2100

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PRINCIPLE

Urban greenery suffers from water shortages and ever more frequent heat waves.

That is why the main principle of the prototype is rainwater collection and distribution.

The prototype is based on a biofilter, which collects rainwater from the roof. The biofilter uses sedimentation and phytotechnology of the plants to purify water from pollutants. Water is then stored in containers, from where it is drop-irrigated to the vertical greenery on the outer walls of the prototype.

In addition, biofilter also retains rainwater, which then evaporates, and improves surrounding microclimate.

The vertical greenery also contributes to better microclimate. Â Vertical greenery is placed on the construction walls in planters with two chambers; one for soil and one for rainwater.

During droughts, the plants draw water from the water chamber through a wick that leads to the roots. When rainwater in the planter runs off, the drip irrigation system with water from the containers is activated.

Prototype operation scheme: solar cells

rainwater harvesting

irrigation system

planter

water tank

battery

biofilter

water tank

Ecological awareness is an important part of the project. The construction mainly consists of pre-dried KVH timber, that do not require any further treatment. Electricity for lighting and electric valve is provided by two solar panels on the roof, which makes the whole prototype energy self sufficient.

* phytotechnology is a collection of natural processes that cure, restrict and prevent soil contamination

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SPECIFICATIONS

Dimensions:

length: width: height:

built-up area: obestavěný prostor:

8.50 m 3.60 m 3.05 m 30.60 m2 85.00 m3 Materials:

construction: reinforcement: roofing: flooring:

dried KVH spruce timber steel column shoes, hangers and angled beams Akyver IR Control polycarbonate larch terrace planks Technologie:

biofilter with phytotechnology drip irrigation system with electric valve pump with a pressure tank 2x100l and 1x200l accumulation tank LED lighting photovoltaic system with battery

+ 3,050

1 500 mm

3 100 mm

1 000 mm

600 mm

+ 0,000

2 000 mm

3 000 mm

3 500 mm

8 500 mm

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DATA

Research period For the duration of operation, the following data were obtained.

2 600 l

56%

Total amount of rainwater that could have been collected, given the roof area.

420 l

Of rainwater fell in just 2 days

Total volume of water containers

71

53

Days of operation

Days without rain

Temperature and rainfall over the period of prototype operation: 1000

Total amount of rainwater (liter)

Maximum temperature (°C)

30

25

500

20

15

10 200 5

27.8 22.8 Installation

3.9

10.9

17.9

24.9

1.10 Operation

8.10

15.10

22.10

29.10 31.10 Disassembly

Conclusion: For the duration of the operation, overall rainfall was relatively low, besides, there were long periods of drought and high day temperatures. Rainfall is very irregular; more than half of collected rainwater fell in just 2 days. To maintain healthy urban greenery, it is necessary to use suitable technology to collect and distribute rainwater for regular watering.

Even with a relatively small roof area (25m2), up to 2600 l of water could have been collected during the operation period.

Total maximum containers and tanks volume was only 420 l, which did not allow to collect all rainwater that fell. In the case of droughts that only take a few days, plants can live from water in the water chambers. However, if drought takes more than 4 days, it is necessary to use the irrigation system.

For further applications, it is necessary to obtain appropriate water distribution for periods of extreme droughts and temperatures.

It is necessary to accumulate as much water as possible and plan its distribution carefully, so greenery can survive such extreme conditions.

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Project description

CCP_City Cell Prototype Climate change adaptation

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