Self-Sufficient City:
vertical farming project
food human
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1. Purpose I assure you that Vertical Farm will improve our food system. However, there are some problems with Vertical Farming that most architects are tackling. The main concern is the cost of building a Vertical Farm with more than 30 stories, and the means of supplying essential elements during production. To borrow Joe Dimeck’s pharase (2009), “Vertical Farming’s greatest flaw is the initial cost as a thirty-story Vertical Farm that takes up one city block feeds 50,000 people and costs $200 million, not counting the
city
price of the land, which could bring the total cost to around $500 million.” My idea of a Vertical Farm does not only concern the method for cultivation, but it also provides education and an experience to change attitudes. This urban agriculture will be developed in a variety of ways in order to change public attitudes. I believe that the change can provide an answer to our future food problems.
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2. Site: Regent’s Canal, York Way Relocation area of Gas tank King’s Cross Redevelopment Area
Camley Street, Natural Park Canal Museum Gas tank King’s Cross Redevelopment Area
ST. Pancras International Train Station
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King’s Cross Station
2.1 Condition There are several important conditions to consider when deciding the site for a Vertical Farm. First, it should be located in heart of the city where all people can easily access. This should be considered in regards to providing basic education about the ease of access to the Vertical Farm for all people. Second, it should be near by a river or canal. As we know, water is one of the essential elements in agricultural activity. The core technology for indoor farming and Vertical Farming is the hydroponics system. Although a hydroponics system requires less water than traditional agriculture, the amount it demands is still substantial. If river water or canal water is used as an alternative to tap water, the hydroponics system will become more efficient. To satisfy both conditions, I have chosen Regents Canal, York Way near King’s Cross Station. Currently there is redevelopment in process at this site. According to King’s Cross official web site, they are developing 67 acres of land here. The area will be filled with residencies, office buildings, commercial buildings, university (University of the Arts London), and a primary school. In particular, there will be approximately 2000 residences and student units, 4.9 million sq ft of offices, and 500,000 sq ft of retail space. Moreover, Regent’s Canal, York Way can be easily accessed due to its location being adjacent to the St Pancras International and King’s Cross Station. The site also has tourist attractions, such as Camley Street, Natural Park, and Canal Museum. For these reasons, it is expected that more and more people will visit and the site will become another landmark in London.
2.2 Regent’s Canal, York Way The canal was built to transport cargo from the Thames River to north London in 1820 by architect and town planner John Nash (London Canal Museum’s website). Currently, it has lost its original function and several houseboats are berthed at Regents Canal. The width of the Regent’s Canal is about 20 to 30 metre. While I was walking York Way, I discovered structures between King’s Cross Station, which were used by the gas reservoir. It was constructed to the south of Regent’s Canal in the 1850s. The structure has an overall height of about 25 m and a diameter of over 35 m. It will be relocated to the north of the canal because of the redevelopment project. Moreover, the project team announced that the gas reservoir will be used as public space (King’s Cross development website). Therefore, I’m planning on transforming this structure into a Vertical Farm. By using the existing structure at the site, the construction cost will be reduced. Moreover, it would be meaningful if the structure that previously destroyed the environment was reused to build an environmentally sustainable building. SELF-SUFFICIENT CITY 13
3. The requisites for a vertical Farm in inner-city The Vertical Farm should have self-sustainable and have the ability for sustainable growth. I listed what the Vertical Farm is expected to have:
Application of
Renewable Energy
Supply of
Fresh Water for Cultivation
Efficient
Technologies for Cultivation
Socially integrated with the Community
Contribution to the
Environment
These are the five key aspects in helping to become a self-sustained building, not just a factory that produces crops. Now we will take a closer look at these five elements.
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Application of
Renewable Energy
Supply of
Fresh Water for Cultivation
Efficient
Technologies for Cultivation
Socially integrated with the Community
Contribution to the
Environment
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3.1 Application of Renewable Energy
The most basic function of Vertical Farming is to cultivate crops indoors. In order to grow plants, they need light, water, air, temperature and so on. We can use natural elements when we do agricultural work outside. However, for Vertical Farming, we have to provide all the elements artificially. In other words, we should consume energy such as LED, heater and ventilation. The followers of Vertical Farming also are aware of the problem of high energy costs. Along with the idea of stable food supply, reducing emission of carbon dioxide is also the purpose of Vertical Farming. If the Vertical Farm consumes a large amount of fossil fuels, it is an obvious contradiction to its purpose. The first thing to do was to research the condition of the selected site in order to get renewable energy.
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Daylight Hours in London First of all, I researched daylight hours to capture solar energy. Table 5 shows daylight hours in London. The table tells us that daylight hours of London change greatly depending on the season. Especially in the case of winter, London’s sunrise is around 8 a.m. and the sunset is before 4 p.m.; ultimately, there are only around 8 hours of sunlight. On the other hand, the summer’s daylight hours are 4:30 a.m. to 9:30 p.m. It is no less than 17 hours of the day (Tukiainen, 2010). There are quite favourable conditions to capturing solar energy in summer, but sunlight is in short supply during the winter. Therefore, these conditions make it tough to supply energy from only solar power. sunrise time
8:00
December November
7:00 7:30
sunset time
15:30 16:00 17:30
October September
6:30
19:00
August
6:00 5:00 4:30
20:00
July
21:00
June
21:00 20:30
May
5:00 6:30
19:30
April 17:30
March
6:00
February
7:00 8:00
January
16:30 16:00
Daylight hours in London
The solar panels should face south. Moreover, the most efficient tilt angle of the solar panels varies according to region and season. In general, the optimum angle is calculated by latitude of the location. If 15 degrees are subtracted from the latitude, that will be the slope angle in the winter. On the other hand, in order to get the slope angle in the summer, 15 degrees should be added to the latitude (Gavlik, 2009). The latitude of London is 51.5 degrees, so the optimum tilt angle is 66.5 degrees and 36.5 degrees from the horizontal. If the photovoltaic roof is used in a fixed position, the tilt angle is equal to the latitude of the location site (Li, 2007). SELF-SUFFICIENT CITY 17
Wind direction and speed in London I researched wind direction and speed to install wind turbines. Here is a figure which shows the result of the investigation. As the diagram indicates, the most common winds in London are from the west and southwest (Kรถnig, 2010). Moreover, the average annual wind speed is 5.5 to 7 meter per second at 25 meters above the ground (Renewable Energy Enquiries Bureau, 2001). It depends on which product is installed, but usually the minimum wind speed at which the turbine generates energy is between 4.5 and 5 m/s. The wind speed rises by 20 % when the distance increases by 10 metre from the ground level. When a wind turbine of 1kw is installed, the annual energy output will be about 2,700kwh. As a result, this will save over 1,400 kg of Co2 (Hammond, 2009). I expect that the Vertical Farm will provide a continuous supply of energy, if there are wind turbines installed towards a southerly or westerly direction.
London wind distribution
N
February
March
April
July
June
May
August
September
October
November
December
E
W
S
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January
Recycle food waste and biomass According to report of Quested (2009), the British throw away 8.3 million tonnes of food annually. Below is a figure which shows the result of his investigation. As the diagram indicates, a large amount of food waste is being dumped in the UK. It has detrimental effects not only on the economy but also on the environment. To resolve this matter, many scientists and environmentalists are trying to make energy from food waste. As I mentioned earlier, the redevelopment project of King’s Cross would accommodate significant numbers of residences and restaurants. Therefore, this Vertical Farming plans to build a relationship with the local residents, stores and so on. This plan is not only to supply fresh and organic vegetables, but also to collecting food waste from consumers. This collected food waste will make bio energy and home composting, which will be used for farming.
U.K Food Waste fresh vegetables and salads fresh fruit
860,000t 500,000t
bakery
680,000t
pre-prepared meals and home made meat and fish dairy and eggs
660,000t
290,000t 530,000t
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3.2 Supply of fresh water for cultivation Agriculture is the largest consumer of fresh water. The activities consume over 70% of world water. More importantly, fresh water is only 2.5% of whole water (Kellogg, 2008). We only use a small amount of water for agriculture, industry and domestic use. A person needs a minimum of 50 litres water per day to drink, wash and cook (Unilever, 2009). On the other hand, a hamburger (150g) requires 2400 litres of water, apple (100g) 70 litres, orange (100g) 50 litres (Hoekstra, 2006). It is a concrete example how much water agriculture consumes. As we know, we are already facing water shortages, and it is an enormous problem throughout the world. Agriculture will be most affected by this problem, and then it will be harmful for human life. A lot of environmentalists assure us that rainwater harvesting can solve this problem. Hydroponics and aquaponics systems require only 5% of the traditional agricultural water requirement. As Wilson (2006) stated, “aquaponics is the world’s most productive food system in terms of water use efficiency, and about one tonne of fish and seven tonnes of vegetables or herbs can be grown for every 22,000 litres of water.� The large scale Vertical Farm needs a lot of water because the water will be both used by plants and humans. This Vertical Farm collects rainwater form the building rooftop. After simple water purification, the collected water is stored in glass tanks near the lifts and staircase. The farm visitors can check the water quality through the glass tank as they use the lift or staircase. It can help people to gain the trust of the farm products and it also is a method of the education about rainwater harvesting. The water for plants uses the stored water. This water will be used after purifying the water by using TiO2 . This water will not only be used for farming, but also be used throughout the building . Used water is either used again after purification, or flows into the canal. Unlike the water used in traditional agriculture, it is safe to allow the water to be used again because aquaponics does not use agricultural pesticides. The building is located above the canal and can use the water from the canal by collecting it with 12 pillars. This water is used in aquaponics and flows in to the canal. This system will allow for water in the canal to be purified.
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Then, how much rainwater can this building collect? According to the Kellogg (2008) method, the Vertical Farm can accumulate rainwater of approximately 665,021 litres annually. This amount of rainwater can produce 30 tonnes of fish and 210 tonnes of vegetables or herbs each year.
rainwater harvesting
Calculating Raincatch Potential 1. Surface area = length x width = 12,200 sq. feet (rooftop)
611mm average annual rainfall in London
2. Raincatch potential per inch of rain = 0.6 gallons x surface area = 7,320 gallons 3. Annual raincatch potential
surface area 12,200 sq. feet
= raincatch potential per inch of rain x annual rainfall = 175,680 gallons (London annual rainfall: 611mm = 24 inches) = 665,021 litres
665,021 litres
=
30 tonnes of fish and 210 tonnes of vegetables
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3.3 Efficient Technologies for cultivation Hydroponics system Most Vertical Farming projects use the hydroponics system because the system uses water without fertile land for cultivation. From a long time ago, it is widely used in commercial greenhouses. This system can grow many more plants in a small space and more rapidly than traditional agriculture. Generally, hydroponics can produce 20 times the amount of crops for the same amount of space and soil (Patten, 2004). Moreover, the hydroponics system supplies us with greater food value than traditional agriculture (Brown,2003) but to do so growers must keep to the growing conditions requirement. As we know, all plants have basic growing necessities such as temperature, duration of light and darkness, carbon dioxide, oxygen, air humidity and so on. These requirements vary with each plant (Bridgewood, 2008).
Aquaponics system The aquaponics system combines aquaculture with hydroponics. The aquaponics system uses the same method as hydroponics agriculture, using only water to grow vegetation without soil. However, using aquaponics we can also farm fish using water that was used for growing vegetation. To quote Price (2004), who is at the vanguard of aquaponics research in the UK, “in aquaponics system waste product from fish, provide nutrient source for the plants, and plants act as a filter for the fish, and we take off cuts plant produce worm in wormery to feed fish. So it is constant reticulated route.� Moreover, he has confidence that aquaponics will be an alternative in future food production. In general, in the commercial greenhouse hydroponics system, a certain amount of artificial nutrients are added to the water. As a result, the crops grow faster. However, because it is difficult to control the amount, this requires an additional sanitation facility; otherwise, the water goes straight in to the river. The aquaponics system, however, gains its own nutrition from the fish and vegetables. Moreover, the system uses fish with animal protein, therefore, it is more applicable to city farming. However, I think that aquaponics may have difficulties with mass production. Aquaponics requires both fish tanks and grow beds for growing plants. Unlike the hydroponics system, which can accommodate multiple grow beds on one floor, the total output of the aquaponics system is markedly lower than the hydroponics system. In response to this defect, I tried to come up with a new design for the aquaponics system. The figure below shows an aquaponics system that is ready for mass production. There will be multiple grow beds over the one fish tank. These grow beds will circulate to the bottom of the fish tank, one by one, regularly and will be filled with the water from the fish tank. If the grow beds go through one revolution, the circulation starts from the first grow bed. Therefore, mass production of the aquaponics system will be possible. 22
Products The purpose for suggesting a Vertical Farm is not to compete with existing farmers around the nation. It is to move away from being dependent on imported products. Aquaponics can grow many kinds of crops. Especially, cucumbers, tomatoes, and leafy plants such as lettuce and fresh herbs – all are grown in large quantities by aquaponics (Logan, 2004). I conducted an investigation into which crops would suit Vertical Farming best last term. As a result, I found that in the United Kingdom, the importing of salad greens and fruit comprises a large proportion of all the other imports. Although, a certain amount of fruit and vegetables are grown in United Kingdom, these are lacking in number to meet British demand and cost more than imported products. This situation will become an obstacle to developing Britain’s agriculture into the future. Moreover, increasing numbers of consumers are demanding fresh organic food; therefore, the foods grown from the Vertical Farm will meet their demands. I also researched fish that can be bred in the farm. Typical fish that are bred in farms are Trout, Tilapia, Perch and Trench. These fish are easily bred if the water temperature is well suited. Especially, Trout and Tilapia are largely in demand because they are full of proteins and mineral. SELF-SUFFICIENT CITY 23
3.4 Socially integrated with the community
The relationship with society is the most important aspect of the Vertical Farm for sustainable growth. I will now present the relations between the Vertical Farm and existing farmers,
citizens and employees.
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With existing farmer Within this Vertical Farm, other programmes that are related to agriculture are integrated. One of the programmes is an agricultural research institute that helps the current agriculture to develop. It develops new technology for agriculture and educates farmers in new techniques. Moreover, it provides an agricultural education system for members of the public who wish to become farmers. The other programme for the farmers is a support centre. This centre is in partnership with the British government. The support centre gives farmers the opportunity to come up with solutions to their problems through consultation. The ultimate goal is not to oppose with the existing farmers, but to be complementary between each other and develop further.
With citizen Fundamentally, the Vertical Farm has a market to sell goods produced. Independent consumers can purchase fresh vegetables and fish through this market. Moreover, the farm allows customers to check the production process. This experience is an important part of improving the reliability of food production. As I mentioned in the biomass chapter, the Vertical Farm provides local restaurants and citizens with ingredients, and collects food waste produced by customers. Primary school students, near the farm, can receive education and practical training about agriculture through cooperating with the Vertical Farm. The aim of the education is to set up a small scale farm in each school. This is a great opportunity for them to learn about the importance of city farming by farming their own vegetables. The public garden located on the 2nd floor will be used as a family farm. The space is to give a chance to families from all socio-economic classes in the city who do not have a chance to farm at all. As a result, the Vertical Farm becomes more community friendly to its users.
With emplyee There will also be job opportunities created at the Vertical Farm. It offers opportunities to young people who are in low income groups or socially disadvantaged and those at high risk of homelessness. It is important to have programmes that help current homeless people; however, it would be better to have a programme before they become homeless. The workers acquire the knowledge and skills of agriculture through education and training, and then they begin agricultural work. Moreover, some people who cannot afford to stay rent their own apartment can stay in the shelter provided by the Vertical Farm. Therefore, with these experiences, they will live a better life. SELF-SUFFICIENT CITY 25
3.5 Contribution to environment Titanium dioxide (TiO2) A photocatalyst is a material that does not change itself, however, it absorbs light in order to accelerate its reaction. It is possible to see the photocatalyst effect in ZrO2, ZnO, Fe2O3, and TiO2. Titanium dioxide (TiO2) is an easily found mineral, therefore, the price is low. Moreover, it is completely harmless to human body. For these reasons, it is commonly used. In 1967, a Japanese scientist named Akira Fujishima discovered that TiO2 gives Photocatalytic activity when it absorbs ultraviolet rays (Fujishima, 2003). This discovery became the base technology for managing environmental problems. TiO2 Photocatalyst is widely used because it is well known for purifying water and air. With its strong Oxidizing power, it eliminates persistent organic pollutants that are hard to resolve due to chlorine and ozone. Therefore, it can remove a certain amount of persistent organic pollutants that are harmful to the environment. It can also eliminate bacteria and dangerous pathogens (Miron, 2004). On the other hand, it also efficiently removes air pollutants such as Nitrogen oxide.
Decomposition of EDC
water- and organic matter cleaning
airDecomposition of aldehyde cleaning NOx removal Photocatalysis of TiO 2 selfDecomposition of oily dust cleaning Superhydrophilicity bactericidal Kill of bacteria MRSA and virus
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building façade =TiO2 coated water pipes water cleaning air cleaning self cleaning bactericidal
This building is covered with 12 plastic pipes to enable the water flow around it. The pipes will be coated in TiO2, therefore, the water will be purified. This water will be supplied to the Vertical Farm and the canal, resulting in fresh crops and a better environment for wildlife and plants that inhabit in the canal. Due to the pipe being located on the building’s façade, it attains its energy from sunlight rather than other alternative energies. It is clearly evident that having a Vertical Farm in the city brings people a few advantages. By having the Vertical Farm, the distance between farm and consumer is shortened. Also, it controls the amount of CO2 in the city. However, I have taken the original advantages further with my research in order to make the Vertical Farm greener.
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