Frequently Asked Questions about “The Plant”

Here are answers to the most popular questions. For a great overview, (and brief!) check out this wonderful video made by Today’s Green Minute.

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

“The Plant” is the name of the building at 1400 W. 46th St., which is owned by Bubbly Dynamics, L.L.C.  “Plant Chicago, NFP” is the name of the non-profit that promotes circular economies of food and energy production, and is a tenant at The Plant. Plant Chicago, NFP conducts research and educational programming in the building (including tours), and runs the weekly farmers market.

How many of the tenants at The Plant are for-profit businesses?

Nearly all of the businesses are 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 with federal tax-exempt 501(c)(3) status. Plant Chicago, NFP conducts research and educates the public on sustainable food production, job creation, renewable energy use, and green building renovation.

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, the growing rooms will be connected 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%.

Are there chickens or bees at the Plant?


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. The 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 the building not only with a backup power source but also the possibility of feeding surplus electricity back to the public grid.
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).

An anaerobic digester will be installed in the back of The Plant 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.

The methane will be pumped 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 the anaerobic digester?

The excellent team over at Eisenmann Corporation!

Carbon dioxide is released when you burn methane, so doesn’t that contribute to global warming?

Short answer: no.

Long answer:  No. Carbon dioxide is a by product of burning methane, but it this process does not contribute global warming. There are 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 why isn’t The Plant contributing to global warming? Because food scraps 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. Furthermore, methane is a Greenhouse Gas (GHG), but it’s over 20 times as potent as carbon dioxide. By burning methane, overall less potent GHG enter the atmosphere. Most food scraps end up in a landfill, which produces methane from anaerobic decomposition (which ends up in the atmosphere).

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 the system at The Plant will be in the form of steam at about 800º F and will be sent to an onsite brewery for 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 the CHP system was powered with natural gas (as many factories do), the building 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 it would still be using a non-renewable energy source. The anaerobic digester will have a renewable source of methane (the main component of natural gas).

Why the focus on food? Can’t this be done with any kind of manufacturing?

Absolutely. In fact, that’s the message of the whole building: manufacturing and growing – both of which use a lot of energy – can happen in a sustainable way. Focusing on small-scale food production as the main focus of manufacturing made sense because the existing building had a lot of valuable food-grade materials. (See below for more information on “food-grade.”) These materials allowed for the creation of safe spaces for food preparation. Had a different building been purchased (which almost happened), food production could have been combined 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 of 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.

Where did all of these ideas come from?

John Edel (owner of The Plant and Bubbly Dynamics) 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.

Who is working on the building plans?

The 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!

Who is doing all the work to renovate this building?

The staff of Bubbly Dynamics and the help of a huge pack of volunteers (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.)

Is it possible to reuse 80% of the existing building materials?

Given that they were found 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 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 of The Plant 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, energy is saved 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. It is estimate that well under half of that will be spent when The Plant is done.

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. If we looked at the project of everyone who asked, we’d never our own project. Sorry!

How many different kinds of permits and licenses are needed to put it together?

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. Thus far, there has been significant government support and a relatively normal (if not slightly better than average) experience with City and State offices.

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.