Paper: The Urban Greenhouse by Sanne de Vries

AR0532 INNOVATION AND SUSTAINABILITY THEORY NO. OF WORDS: 2486 RELATED LECTURES: SUSTAINABLE INNOVATION - ANDY VAN DER DOBBELSTEEN BENEFITS OF GREEN - JORIS VOETEN BIOMIMETIC ARCHITECTURE - GREG KEEFFE HELIOTROPOLIS - CRAIG MARTIN SANNE DE VRIES 4005414 MSC2 ARCHITECTURE, TU DELFT 13-04-2014

EXPLOITING SYNERGIES BETWEEN HOUSING AND AGRICULTURE

THE URBAN GREENHOUSE

Introduction 3 An opportunity for synergism

Architectural integration 4 the heat system 5 the carbon cycle 6 the water system 6 the nutrient system 6 Conclusion 6 Bibliography 7

The lecture series Innovation and Sustainability Theory has addressed a thinking behind opportunities in sustainable design that seemed to be recurring among various speakers. With a wide range of similar but distinctive interpretations, my attempt of translating this opportunity finds itself in the words ‘synergism’ and ‘localization’. One example that was given by Andy van der Dobbelsteen in his lecture Introduction to sustainable integration strikes me as a perfect model on integrating the concept of those words; the combination of greenhouses with other building functions, enabling both to profit from one another by creating closed cycles.1 Only few examples of such systems have been built up to today – such as the Villa Flora in Venlo – however, the idea behind it seems very promising. This paper will argue the relevance of what I will name ‘the urban greenhouse’ as a way of dealing with current sustainability issues and will furthermore explore how such systems can be applied beneficially in our built environment.

Finding ourselves in a time of gradual recovery from a global economic crisis, an increased awareness can be witnessed on the necessity for a different foundation of our economic and environmental systems in order to ensure a brighter future. Commitment to longterm sustainability is becoming more and more widely acknowledged in providing such a different approach.2 It is therefore an important moment for the building sector in taking the leap towards both developing and applying ideas on sustainability in the built

1 Andy van der Dobbelsteen, Introduction to Innovation & Sustainability, (Faculty of Architecture, Delft: Delft University of Technology, 2014). 2 James Buchanan, "Sustainability and the Economic Crisis," Xavier University, http://www.xavier.edu/green/ Sustainability-and-the-Economic-Crisis.cfm.

environment. At the same time, another concern is raised; that of a globally dysfunctional food system. Although these topics might at first glance not seem very closely related, I would like to take the opportunity here to point out how criticism on the malfunctioning systems go back to the same roots. In the late 1970’s, departing from the Great Depression, free market reforms eroded support for local agriculture through the elimination of grain reserves, government supports, extensions and credit services. At the same time, banking became more centralized; over 8.000 bank mergers took place in the US alone between 1980 and 1998. Loans to small businesses – including farms – became harder to come by, which left many farmers to get big or get out. These trends have resulted in a massive consolidation in the agriculture industry.13 A globally organized food chain system has caused us to lose grip on related activities such as feeding, fertilizing, primary and secondary processing, packaging, storage, transportation, marketing and waste disposal. The building industry has gone through a similar process with the consolidation of the corporate world. Thus, the same effects can be witnessed for the designing of the built environment; economic constraints often result in the application of (mass-produced) products that have been processed all over the world. The complexity of combining different products in contemporary buildings and the global accessibility to them make it a difficult task to track down the path of the resources that we are using. This goes for both the materialisation of buildings and products providing for the continuing need on maintaining the desired indoor climate such as energy, water etc. For this reason, finding out whether using or applying a particular product is sustainable can be challenging, just like finding out what is the sustainability factor of the food we are consuming can be very difficult. 3 Annie Shattuck, "The Financial Crisis and the Food Crisis: Two Sides of the Same Coin," (2008), https://www. foodfirst.org/en/node/2252.

An important effect of our current crisis is a changing attitude of society towards economical, health and environmental issues. According to Everett Rogers’ diffusion of innovation theory, the process of innovation – in this case sustainable innovation – starts out with innovative development by innovators, successively followed by early adopters, an early and late majority and at last the laggards.14 Examples of sustainable development of different kinds by innovators and early adopters can already be perceived and are starting to become more recognized by a broader public. The raise of awareness that is occurring could very well imply that an early majority in our contemporary society finds itself in the first stages of Rogers’ process known as the stages of firstly knowledge and then persuasion. Increased awareness and knowledge is a major step in the process towards innovation and the time is getting more and more ripe for major change. A view that is shared by many is that measures providing oversight on large traders and financial services and increase support to local economies, small farmers, small, local banks, and small borrowers will strongly contribute to a solution for a sustainable society.25 These kinds of measures enable us to gain renewed insight in where the resources that we use are coming from and to what extend they might be a burden to our environment. In this sense, again parallels can be drawn between the building and agriculture industry. Consumers are getting more concerned with health and environment and attitudes are becoming more critical regarding centralized food mass production. Local and seasonal food production is pursued increasingly as it is – as opposed to centralized mass production – in many ways less of a burden to both our environment and our health. The argument is twofold. Firstly, it avoids problems such as unethical food production through poor working Image 1: Rogers ‘Diffusion of Innovation (Rogers)

4 Everett M Rogers, Diffusion of innovations (Simon and Schuster, 2010). 5 Shattuck, "The Financial Crisis and the Food Crisis: Two Sides of the Same Coin".

conditions, negative transportation climate effects, the addition of unhealthy artificial ingredients and decrease of freshness due to transportation and storage. But not only that; localizing our food cycles enables accessibility to knowledge and thus our awareness on those activities. In the building industry, designers similarly start to revalue an architecture that is contextual, in the sense of trying to work together with (local) natural resources that are present on and around the site in order to provide the desired needs for materialisation, daylight, thermal comfort, water, ventilation and energy. It is at this critical point in time where the root problems and consequently the future aspirations for change of two different sectors meet that fruitful synergies can be explored. It can actually be considered a very logical step. Customers want their food production to be localized so they can have more control. Designers and planners are aiming to localize buildings’ in- and output cycles. In order to create smaller ecosystems we need to reunite nature and humans – like an ecosystem is naturally intended.

To explore the possibilities of applying a system where housing and greenhouses are combined, an initiative of InnovatieNetwerk called ‘de Zonneterp’ will be analysed. This initiative has done investigation on this theme and proposed possible designs for two places in the Netherlands; Westland and Bergerden – which have up till now not been executed.16 This example is chosen because it combines the greenhouse with the particular function of housing, building literally on the idea of a food cycle that is closer to home. Additionally, it can provide other social benefits in the living environment, like playing and education for children, 6 E.J.S.A. Wortmann, "De Zonneterp – een grootschalig zonproject," in Achtergrondrapporten (Utrecht2005).

as well as the experience of living in a close relationship with nature. One of the few examples of the urban greenhouse combined with housing can be found in the town Arcosanti. The town is a living, experimental laboratory for the arcology theories of Italian architect Paolo Soleri. He introduces arcology - a literal joining of the words architecture and ecology - as an alternative to today’s hyperconsumption; a self-reliant urban system that functions through closed ecosystems. The management of this project is now led by Jeff Stein, who himself is living in Arcosanti. He describes his experience of living with the urban greenhouse as pleasurable: ““We have a couple of small solar greenhouses attached to buildings here. One of them is attached to my apartment, and I can just open a little door in the bottom of my living room wall in the wintertime and this wonderfully fresh 120-degree air from plants and from the sun comes wafting into the apartment. It’s fragrant because plants are flowering, it is oxygenated because of the plants, and moist because the plants are transpiring moisture. Everybody should have this experience.”17

Jeff Stein

InnovatieNetwerk supports their choice for housing with practical reasons. The heat production of the greenhouse needs to be in balance with the heating demand of the combined function. It is therefore important to already in the design phase be able to make accurate predictions on energy consumption and material flows. The high predictability level of housing functions as opposed to utility makes it suitable.

Image 2: Heat system in ‘Zonneterp’ (www.zonneterp.nl)

In the ‘Zonneterp’ format, four synergic cycles can be distinguished, which will be elucidated in the next paragraphs.

7 Karen T. Grajales, "Interview with Jeff Stein," American Society of Landscape Architects, http://www.asla. org/ContentDetail.aspx?id=37682.

• The heat system (Joule) • The carbon cycle (C) • The water system (H2O) • The nutrient system (N)

The heat system The urban greenhouse relies on the principle of the energy-producing greenhouse; this is a closed system where the greenhouse is heated by the sun, after which excess heat is collected and can be used for other purposes. It is a Low Temperature Heating system (LTH), which is defined as providing supply heat is no higher than 55 degrees and return heat that has a maximum of 45 degrees. Heating with low-grade heat has plenty of advantages: higher efficiency, less heat loss through distribution, lower energy use, higher thermal comfort and a higher safety level. In the ‘Zonneterp’, the supplied heat will have an average heat supply of 25 degrees and return heat of around 21 degrees. The heat is carried and transported by (ground)water that is in contact with thermal mass and a heat exchanger in the greenhouse. This heat exchanger exists of thin tubes filled with water that are in contact with the thermal mass. Along these tubes a thin wire is woven, creating a maze along which an air stream is lead. Both the tubes and the wire are of copper for optimal thermal conduction. Depending on the temperature difference between the air and the maze, the air stream will be cooled or heated (as goes for the water). In the design of the Zonneterp, an underground water-bearing layer of sand is used as thermal mass; this is called an aquifer. Sun heat is stored here and can be regained from wells with different

temperatures; A cold well (8 degrees) a lukewarm well (18 degrees) and a hot well (25 degrees).18 The carbon cycle

Image 3: Carbon cycle in ‘Zonneterp’ (www.zonneterp.nl)

In a closed greenhouse system, there is a need for CO2 supply; plants use this for growing. The formula for plant growth is: CO2 + H2O = CH2O + O2. To create a closed carbon cycle, the carbon has to be retrieved from organic plant and human waste, or biomass, again. This is done through anaerobic fermentation. The advantage of this method as compared to combustion is that it is not necessary to first let water evaporate from the biomass, and it does not produce strongly polluted flue gasses. The results of this fermentation process are biogas, effluent (fluid) and digestate (solid). The biogas, existing for about two third of burnable methane and for one third of carbon dioxide. It is used then to produce electricity, warm water and carbon dioxide supply of the greenhouse. The produced effluent is taken in by the water cycle, eventually ending up as a supply for the plants. The digestate will be used as a substitute for a peat soil in the greenhouse.29 The water system

Image 4: Biogas energy balance (www.zonneterp.nl)

Image 5: ater balance in ‘Zonneterp’ (www.zonneterp.nl)

As opposed to a traditional greenhouse, in a closed system water cannot leave the greenhouse. The process of evaporation and condensation does help to cool down the greenhouse, with clean moist as a result. This will then be processed into drinking water through filtering, adding calcium and applying quality control techniques. Very little water is necessary from the regular water network. The waste water coming from the dwellings are separated into a black water stream (nutrient rich toilet water) and a grey water stream for remaining household activities. The black water stream will 8 Wortmann, "De Zonneterp – een grootschalig zonproject." 9 Ibid.

then be fermented, extracting energy in the form of biogas. Waste effluent will be added afterwards to the grey water stream, which is used as nutrient rich water for cultivating the plants. In order to keep the black water as dry as possible, vacuum toilets that use a minimum amount of flushing water are applied. The water system actually does not differ so much from regular water purification methods, except it is decentralized and on smaller scale. Furthermore, more energy is retrieved from the water trough separation and fermentation.10 The nutrient system One of the qualities of the processed water supply is its richness of nutrients, of which the most important for the plants are nitrogen (N), phosphorus (P) and potassium (K+). In the nutrient cycle, nitrogen requires the most attention. In the black water stream it can be found in the form of ammonium. A problem is that with substrate farming plants cannot absorb this form of nitrogen. Furthermore, if there is too much nutrient it would have to leave the greenhouse as waste water, which is not the most environmental friendly way. Therefore, ammonium will be converted into nitrate and nitrogen through processes of nitrification (NH4+ +2 O2 -> NO3- + H2O + 2 H+) and denitrification (NO3- + organic matter -> N2). Part of the N2 gas will escape into the atmosphere, discharging excess nutrient in an eco-friendly way. The rest will end up in the greenhouse with the water.211

In summary, combining the greenhouse with urban functions such as housing connects strongly to a different way of thinking of which its necessity we are now becoming aware. This mentality includes decentralization and localisation. The new typology that is created can be greatly self10 11

Ibid. Ibid.

sufficient. Different cycles – heat, carbon, water and nutrient – are created through combining the needs and wastes of both farming and housing, perfectly completing each other. In order to apply such systems in the future, organisational models and architectural typologies need to be explored further, so that this typology can possibly become to play a significant role in our achievement towards a sustainable society.

Image 6: Nitrogen balance in ‘Zonneterp’ (www.zonneterp.nl)

Buchanan, James. “Sustainability and the Economic Crisis.” Xavier University, http://www. xavier.edu/green/Sustainability-and-theEconomic-Crisis.cfm. Dobbelsteen, Andy van der. Introduction to Innovation & Sustainability. Faculty of Architecture, Delft: Delft University of Technology, 2014. Grajales, Karen T. “Interview with Jeff Stein.” American Society of Landscape Architects, http://www.asla.org/ContentDetail. aspx?id=37682. Rogers, Everett M. Diffusion of Innovations. Simon and Schuster, 2010. Shattuck, Annie. “The Financial Crisis and the Food Crisis: Two Sides of the Same Coin.” In, (2008). Published electronically 24 September. https://www.foodfirst.org/en/ node/2252. Vermeulen, Sonja J., Bruce M. Campbell, and John S.I. Ingram. “Climate Change and Food Systems.” Annual Review of Environment and Resources 37, no. 1 (2012): 195-222. Wortmann, E.J.S.A. “De Zonneterp – Een Grootschalig Zonproject.” In Achtergrondrapporten. Utrecht, 2005.