Frequently Asked Questions

We get tons of questions about the specifics of The Plant. While we can’t answer them all, here are answers to the most popular questions about what we’re doing. For a great overview, (and brief!) check out this wonderful video made by Today’s Green Minute. And do note that when we’re closer to completing the project (2016, perhaps), we’ll post a case study with everything we can possibly tell you about The Plant.

What is a vertical farm? Why not just call it an indoor farm or a greenhouse?

The definition of a vertical farm varies, but we use the term to refer to:

  1. Farming in multiple stories of a building, and
  2. Farming from floor to ceiling in a room.

Yes, it generally happens to be indoors, but the point is that you are planting more layers of crops per square acre than you would on a single flat farming surface.

What is aquaponics? Is it the same thing as hydroponics?

Nope. Aquaponics is the combination of aquaculture (growing fish in a farm setting) and hydroponics (growing plants in water and without soil). The great thing about aquaponics is that it is an almost fully-closed ecosystem. In other words, it requires very little input (just some fish food and some micronutrients) and generates almost no waste.

Aquaculture is generally bad for the environment because the fish farms release tons of polluting fish waste into nearby lakes, rivers and seashores. That waste has nutrients in it that algae use to grow, so when there’s a big influx of nutrients, algal blooms result. The algae release toxic chemicals into the water and also absorb dissolved oxygen in the water, killing other sea life. (Notably, fertilizer that runs off conventional farms causes the same problems.)

Hydroponics requires the addition of nutrients (usually in the form of expensive chemicals). Fish waste is very high in ammonia, which is a form of nitrogen. If there’s too much ammonia in the water, it will kill the fish (and plants!). But nitrifying bacteria can break ammonia down into nitrites, which the plants can absorb. So, in aquaponics, the fish, bacteria, and plants all rely on each other to thrive.

Why tilapia and not some other kind of fish?

Growing tilapia has a number of advantages:

  1. As fresh-water fish, they don’t require a salt-water system (which would be far less suitable for growing vegetables).
  2. They grow quickly and so can be harvested after about 10 months.
  3. They naturally thrive in a crowded tank and can easily tolerate a range of temperatures and water qualities
  4. We are able to cross two different breeds that, together, produce only male babies. (Kind of like breeding a horse and a donkey to get a sterile mule.) By keeping only male fish in our growing tanks, we prevent breeding, which allows us to keep all fish of the same size. This helps to keep our system in balance and to prevents the problem of bigger fish eating the smaller ones.

You can also grow perch, freshwater shrimp, and other kinds of fish.

Why mushrooms?

Because they’re tasty! Mushrooms are one of nature’s decomposers, so they’re great for making further use of “spent” material like brewery mash (mash is grain that’s been heated in water to make the beer).

What is kombucha?

Kombucha is tea that has been fermented with a combination of bacteria and yeast. The neat thing about kombucha (aside from its effervescence and delicious taste) is that, like all fermenting things (including the beer that will also be brewed at The Plant), it puts off carbon dioxide and absorbs oxygen. Conversely, plants absorb carbon dioxide and release oxygen. To take advantage of these outputs, we’re going to connect the growing rooms to the fermenting rooms (both beer and kombucha) and circulate the air between them. Doing so will improve plant growth—some estimates suggest up to 20%.

Do you plan to raise chickens or bees at the Plant?

Definitely bees and likely chickens. We’re looking into what’s allowed under the City of Chicago’s new Urban Agriculture ordinance.

What does it mean to be net-zero energy?

The Plant will produce all of its own electricity and heat on site and using proven technologies. Our anaerobic digester will take in food waste (everything from spent distillers grains to vegetable produce waste to beef-fat sludge), digest it, and release methane into a combined heat and power (CHP) system. This system will supply the building with heat and electricity. The Plant will remain connected to the public electrical grid and natural gas pipeline, providing us not only with a backup power source but also the possibility of feeding our surplus electricity back to the public grid.

So while we may occasionally take power from the grid, we will also be giving it back, leaving us with a net-zero usage level.
Anaerobic Digester

What is an anaerobic digester and how does it work?

All organic matter breaks down over time, eaten by bacteria that’s all around us—it’s nature’s way of recycling matter and redistributing nutrients. This process can happen in two ways:

  1. Aerobic digestion happens in the presence of oxygen. It generates carbon dioxide, solid compost, and liquid compost (also known as compost tea, a great fertilizer for gardens).
  2. Anaerobic digestion happens in the absence of oxygen. It generates methane gas, digested solids (sometimes called digestate), and digested liquids (sometimes called a liquor).

In the back of The Plant, we will be installing an anaerobic digester that takes in food scraps, digests them and releases methane into a covered storage tank. The digester will produce three different, valuable materials:

  • Humus-like solids, which can be mixed with soil for a light-weight green roof soil blend,
  • Nutrient-rich liquids, which can be diluted and applied anywhere that needs fertilizer, and
  • Bio-gas, which is about two-thirds methane and one-third carbon dioxide.

We will pump the methane to a combined heat and power system, which will be burned in a generator. That combined heat and power system will produce:

  • Electricity, which will power the building;
  • Heat, which will run through a absorption chiller, which is used to regulate the temperature of the building;
  • Carbon dioxide; and
  • Water.

(Little known fact: most industrial buildings generate so much heat as a byproduct of industrial processes that they actually need to be cooled year-round. This is particularly true of The Plant, which is both very well-insulated and will produce heat from food manufacturing, beer-brewing, and grow lights.)

Why not do regular aerobic composting?

Regular composting produces only carbon dioxide – unless it doesn’t get enough oxygen, in which case it produces methane. (This is a bad sign in regular composting because the methane from the compost pile, when not captured and burned, is released into the atmosphere where it acts as a highly potent greenhouse gas.)

Carbon dioxide is a very stable molecule, which means it’s hard to break apart the bonds. (Breaking the bonds of molecules releases energy.) Methane, on the other hand, is relatively unstable; the bonds can be broken at a lower temperature – low enough that it’s a great source of fuel for running a turbine.

Who is installing your anaerobic digester?

The excellent team over at Eisenmann Corporation!

Don’t you release carbon dioxide when you burn methane? Doesn’t that contribute to global warming?

Yes, we will release carbon dioxide by burning methane, but no, our methane will not contribute to global warming. There are basically two sources of carbon dioxide in the atmosphere:

  1. The carbon cycle is the age-old process through which the Earth circulates carbon between the atmosphere and plants. Plants absorb carbon dioxide and use it to make sugars internally, which helps them grow. After those plants die, they decompose and the sugars break back down into carbon dioxide – the same amount of carbon dioxide they took out when they were alive. While there are sometimes fluctuations, the carbon cycle by itself creates relatively stable levels of carbon dioxide in the atmosphere.
  2. Global warming is the result of extra carbon dioxide emitted into the atmosphere in addition to what’s moving around in the carbon cycle. Burning fossil fuels releases carbon dioxide that was trapped underground millions of years ago. It comes from plants that decomposed underground and were turned into oil, coal, or natural gas. This long-lost carbon dioxide is much more than the Earth is currently adapted to use. The increased CO2 levels are creating what is known as the “greenhouse effect.” This happens because the Earth reflects back into space some of the heat from the sun, but every carbon dioxide molecule acts as a tiny mirror, re-reflecting that heat back to the Earth rather than allowing it to escape into space. By adding enough extra carbon dioxide to the atmosphere, we are heating up the global climate and changing weather patterns around the world.

So, back to our original question: why isn’t The Plant contributing to global warming? Because we’re using food scraps that are already a part of the current carbon cycle: those plants would grow, die, and release carbon dioxide regardless of whether or not we harnessed their energy.

What is a combined heat and power (CHP) system?

A CHP system is an engine attached to both a turbine and a heat recovery unit. The turbine creates electricity and the heat recovery unit captures the heat released from the engine. The heat released in our system will be in the form of steam at about 800º F and will be sent to an onsite brewery for their brewing process. The steam will return at about 200º F and will be sent through an absorption chiller, which will chill (or heat, if needed) water running through tubes throughout the building. That water will cool or heat the building as needed.

Absorption chilling is a complex process explained in greater depth here.

Also, it’s important to note that if we powered the CHP system with natural gas (as many factories do), we would enjoy the efficiency of jointly producing heat and electricity (it’s about double that of pulling using electricity off the grid and creating heat in a boiler), but we would still be using a non-renewable energy source. That’s why we’re putting in the anaerobic digester: to create a renewable source of methane (the main component of natural gas).

How did you come up with all of these ideas?

John Edel, the Executive Director, has been thinking about growing plants in buildings since his childhood visits to the Garfield Park Conservatory, with its towering palms and lush gardens all growing indoors. He also knows a lot about manufacturing and has spent a lot of time researching the industrial history of Chicago.
He wanted to create a space where manufacturing and indoor growing could happen together. Both processes use a lot of energy. The CHP system produces both the heat needed for manufacturing and the electricity needed to run the grow lights.

To develop these ideas, John has worked closely with students from the Illinois Institute of Technology, as well as friends from the community (many who have come through on building tours) with suggestions about other possibilities for symbiosis.

Why do you focus so much on food? Can’t this be done with any kind of manufacturing?

Absolutely. In fact, that’s the message of this whole building: manufacturing and growing – both of which use a lot of energy – can happen in a sustainable way. We’re focused on small-scale food production as our main focus of manufacturing because we happened to find a building with a lot of valuable food-grade materials. (See below for more information on “food-grade.”) These materials allow us to create space safe for food preparation. Had we chosen a different building (and we almost did), we could have combined growing with some other type of manufacturing.

All kinds of industrial buildings can be repurposed to house manufacturing and growing systems powered by renewable energy and to create jobs. This is the point we’re proving with The Plant! You can do this anywhere to great benefit to society.

What does it mean to be food-grade?

“Food-grade” means that a space is safe for food preparation, according to very strict government health and safety standards. When the former owners, Peer Foods, were processing meat in the building, they had to meet standards set by the U.S. Department of Agriculture that required most of the building to be made out of materials like FRP (fiber-reinforced polymer) on the walls and sanitary brick or a rubberized concrete on the floors. There’s also lots of high-grade stainless steel throughout the building that we’ll be reusing in kitchen spaces. These materials prevent mold and bacteria growth, they’re easy to clean, and stainless steel doesn’t corrode. Notably, the USDA required meatpacking plants to get rid of asbestos and lead piping a long time ago, so we are happy to say there’s none in The Plant.

Who is working on the building plans?

Our architects are Rashmi Ramaswamy and Mike Newman of SHED Studios, who have worked with us from the beginning. Also, Ryan Wilson and Marcus de la Fleur have been closely involved in site design. They’re all great!

How much work do you have to do to renovate this building for your purposes?

A lot! We estimate that between our staff and volunteers, we’ve put in about 15,000 working hours between July 2010 and February 2012.

Who is doing all the work?

Our staff and a huge pack of volunteers. We have two full-time staff members, three part-timers (see more about them on our Staff page), four long-term, very dedicated volunteers, and a few interns in and out. We’ve had easily 1,500 volunteers help, some for just a day, some who come back regularly.

What is deconstruction?

Deconstruction is the opposite of construction: it’s the careful removal of materials from a building with the intention of reuse. Demolition, on the other hand, is the destruction of a building without much regard for keeping building materials intact. (For more information on deconstruction, see Chicago’s ReBuilding Exchange.)

Can you really reuse 80% of the existing building materials?

Given that we found them in such good shape, yes. Keep in mind that much of this figure refers to the building’s physical structure – the brick walls and concrete floors. But we are going to great lengths to remove other materials in a functional state so they can be reused.

Isn’t that a lot of trouble?

Yes, it is! But we believe that there is both monetary and intrinsic value in doing so. Tearing down buildings anywhere leaves gaping holes in the fabric of the city, especially in neighborhoods like Back of the Yards. To the north and east there are huge factories, but to the south and west there are homes. Leaving a building vacant makes people wary of it because it invites criminal activity. Tearing a building down puts a big hole in the area. And a recent study suggests that even if you tear down a warehouse building and replace it with an office building that’s 30% more efficient, it will still take 12 years to recover the energy spent in actually constructing the new office building. By making use of the energy embedded in this building, we are saving the energy that would be spent building a new one.

Does it save money?

Absolutely. To construct a new industrial building in Chicago costs roughly $70 to $85 per square foot. To construct a glass building that would let light in could be upwards of $200 per square foot. We estimate we’ll spend well under half of that when we’re done. Also, we will eventually put up a business case study when we’re finished to show the details.

Can you take a look at the specs of this building I’m interested in buying and tell me if it will work?

Unfortunately, we can’t. For one thing, evaluating a building for holding thousands of tons of fish tanks really requires a structural engineer. But also, we’re a tiny staff of five (two full-time, three part-time, plus some wonderful, high-contributing unpaid volunteers). If we looked at the project of everyone who asked, we’d never finish The Plant. Sorry! But, again, a case study will be posted in the next couple years to show even more detail about what we’ve done.

What is the difference between “The Plant” and “Plant Chicago”?

“The Plant” is the name of the building we’re in at 1400 W. 46th St. It is owned by Bubbly Dynamics, L.L.C. (which is in turn owned by John Edel, the Plant’s Executive Director.) “Plant Chicago” is the name of the non-profit that owns and operates most of the vertical farming space in the building (some is operated by other tenants). It will also own and operate the shared kitchen planned to be built out by roughly 2014, and will conduct research and educational programming in the building. Plant Chicago is technically a tenant of The Plant.

How much of the business at The Plant will be for-profit and how much nonprofit?

Nearly all of the businesses will be for profit by virtue of the fact that they deal with raising and preparing food, which is generally a private enterprise.

The major exception is Plant Chicago, NFP, which is an Illinois-registered not-for-profit corporation and is seeking federal tax-exempt 501(c)(3) status. Plant Chicago will conduct research and educate the public on sustainable food production, job creation, renewable energy use, and green building renovation. To that end, it will own and operate about 22,000 of the 30,000 s.f. of growing space (where the research will take place) as well as the shared kitchen (where the job creation will take place). It will also host extensive educational programming to teach adults and children about The Plant.

This sounds like a complicated business. How many different kinds of permits and licenses do you need to put it together?

Lots, and we’re not done yet. The renewable energy system will likely require at least 8 separate city- or state-based permits or approvals for air, water, waste, and zoning. The building itself requires all of the standard construction permits. We believe that honesty is the best policy; we have been very open with all government officials about what we’re trying to do. Thus far, we’ve received significant government support and appear to have had a relatively normal (if not slightly better than average) experience with City and State offices.

When will The Plant be up and running?

The building will become functional in stages. Right now, we’re focused on getting a number of tenants in. We should have about five spaces fully built out and leased by the end of 2012. We’re also working very hard to get the renewable energy system up and running by June 2013.

Next will be the shared kitchen space, which will probably be done in 2014, and then the outdoor gardens, which have to wait until after the renewable energy system has been installed because it involves a lot of outdoor construction in the yard. Throughout all of this time, we’ll be building out the indoor growing spaces with aquaponic and mushroom farms. We expect the whole building to be completed, including the lobby and common areas sometime between 2016 and 2017.

When you say 125 jobs, what sort of jobs do you mean?

Everything from people who work on the aquaponic and mushroom farm to people who own their own small- or medium-sized food-related businesses (think bakeries, catering companies, fermenters, etc.).
Jobs will mostly be created in two areas:

  1. Growing and harvesting food, and
  2. Preparing that food for sale to restaurants or directly to the public.

We’ll have farmers working on the aquaponic and mushroom farms, sous chefs and head chefs catering events, and bakers making cookies and cakes. We also expect the brewery to create a number of jobs to manage all stages of the brewing process. Also, The Plant itself will create a few management and building-related positions.

How can I help?

You can volunteer and you can donate! See each page on our website for more information. And, thanks! All your help goes to making The Plant a success.