The decision you make of where to set up your Tower Farm is a critical one. Whether it is outdoors, indoors or in a green house, there are important factors to be aware of before you begin.
Outdoor Tower Farm
When setting up a Tower Farm outdoors, your challenges will include the weather factor, which hinders a Tower Farm operator from being able to forecast crop yields somewhat accurately. An outdoor Tower Farm needs to have a planting strategy according to the weather and seasons. You also need to manage unwanted pests and insects, as well as, wild animals to keep them from damaging or destroying the crops. If you decide to set up outdoors we might suggest building a metal galvanized building, similar to the one used by King Tower Farm in the Philippines. This structure also has a micro netting mesh that has been attached to the entire structure, which helps protect the crop from unwanted insects. The mesh also allows the introduction of beneficial insects, such as ladybugs, within the structure and they will help alleviate aphids. The metal structure keeps the wild animals at bay and you can stretch a shade cloth over the structure to offset some of the heat of the burning sun in the summer months. If you are in an area that is prone to major storms or high winds, you can even install a galvanized pole structure to stretch as a windbreaker. A galvanized metal structure is extremely cost-effective, and offers immunity against strains of microorganisms, which helps the Farm to be more resistant to plant diseases, and is a highly recommended method when farming outdoors.
When farming outdoors on a rooftop, we advise using towers featuring either 28 planting ports or 36 planting ports maximum in height. The increased wind factor on rooftops, limits the height of the towers.
Indoor Tower Farm
Many new investors considering the food security industry think about converting warehouses into indoor farms operating with artificial light. It is most definitely possible but, there are many considerations at stake:
- Warehouses need to have suitable insulation and be equipped with equipment allowing acceptable levels of air exchange. This is a very important consideration.
- In most cases, a full Control system (i.e. PRIVA) needs to be installed for controlling the humidity, the temperature, the CO2 levels, etc.
- A substantial investment in the artificial light system is imperative. Any Tower Farms featured in airports, convention centers, or any other area without natural light are using artificial lights as follows: Minimum 1000 watts per fixture, regardless of type… MH, HPS, or LED. Fixtures need to be mounted at least 3 feet above the top of the Tower, regardless of Tower height.
- A support structure is needed. An example to review is the one featured at Chicago O’Hare airport (which was custom-built). Alternatively, lights can be hung from a ceiling truss. You will need to consider an appropriate layout of the lighting system. You will want to use 1.1 light fixtures per tower in a staggered array to get sufficient coverage. Example: 100 Towers x 1.1 = 110 fixtures, minimum.
- Run time for the lights will be 10-14 hours per day, depending on the crop, ambient light, etc.
Note: Aside from the extra initial investment related to the artificial lights, the cost of powering an indoor farm (even with LED lights) needs to be taken into serious account.
Greenhouse Tower Farm
A climate-controlled greenhouse is the best option to run a Tower Farm successfully 12 months of the year.
Some things to consider when greenhouse Tower farming:
- With a greenhouse you will be able to grow vibrant greens and herbs year-round, regardless of seasons or extreme weather, thus allowing a Tower Farm to make production commitments to its buyers.
- Greenhouse structure to run north to south ALWAYS. Tower Garden rows to run north to south ALWAYS.
- Full sun exposure and/or supplemental lighting is required for year-round production.
- If lighting is needed, High-Pressure Sodium is the most cost-effective for a greenhouse farm.
- Oversized Fan and Pad evaporative cooling system is needed.
- Cooling pad w/motorized vents on the north end, and 2 stage exhaust fans on the south.
- Seedling propagation always on north end near cooling pad for pest prevention.
- Additional specifications and components may be needed for a larger Tower Farm using a Gutter Connect Greenhouse min. 16’ sidewall height desired.
- Single-layer polycarbonate on end walls, sidewalls, and top of greenhouse
- GE Soft light is best in class for diffusing light and cooling
- Roof vent, for additional heat bleed-off
- Gable fan and motorized louver is cheaper but less effective
- Length – Do not exceed 120’ in length between fan and pad
- OPTIONAL: Fogging system as stage 2 cooling (mainly for desert, can increase greenhouse length), requires RO water and can be expensive.
- High-end controller – PC based w/alarms, weather station, climate sensors
- We would suggest engineered drawings for electrical stub up locations
- Floor slope to be specified at ½” per 12 feet for level Tower operation
- Fan forced, vented gas heater required for tropical climates that experience seasonal cold events.
- The ideal temperature inside a greenhouse is 72°F to 77°F (22°C to 25°C). However, this is just an “ideal guideline”. Crops such as hot peppers, okra, cannabis, etc., can sustain a much higher ambient temperature than crops such as spinach, lettuce… It is recommended to have a differential temperature with cooler temperatures at night than the daytime.
- Ideal light is natural sunlight, a minimum of 12-14 hours per day. The Daily Light Integral required for most food crops for ideal growth is 12-16 moles per square meter per day.
Note: When speaking about the cost per square meter for a climate-controlled greenhouse, it is for the greenhouse and the whole climate control system (fans, atomizers, wet walls, central computer system).
Such a rate does not include building costs nor the foundation nor shipping. Rates quoted are usually FOB.
It takes approximately a crew of 10 workers to build, assemble, and configure a 1000 m² climate-controlled greenhouse fully ready to operate. Ideal light is natural sunlight, a minimum of 12-14 hours per day. The Daily
Light Integral required for most food crops for ideal growth is 12-16 moles per square meter per day. Typically, after the order has been placed, it takes greenhouse manufacturers 6 to 9 weeks on average to be ready to ship the greenhouse. Payment terms are generally 50% upon placing the order and the remaining 50% upon shipping the merchandise. When the deposit has been issued, generally, the manufacturer will send a blueprint for the foundation as well as the anchors for the structure. A greenhouse proposal will include the structure (which is built by the manufacturer), fans (usually built by another manufacturer), atomizers/foggers (usually built by another manufacturer), CO2 regulators (usually built by another manufacturer), etc. Let’s say that greenhouse manufacturers build the structure and gather all the parts for the climate control system from other manufacturers.
You do not have to be an expert to run a greenhouse. Greenhouses are fully automated systems that just require you to follow instructions. However, you may want a greenhouse expert’s assistance to buy your greenhouse. Aside from guaranteed savings, you will be buying what you really need. It is not just a matter of saving money but, spending your budget on the appropriate greenhouse system right from the start.