Recycling & Waste Minimization
- Recycling Overview
- How Recycling Works at UIC
- Recyclable Materials
- Great Stuff Exchange
- Data Reporting
The average American generates 4.4 pounds of trash per day, adding to the grand total of about 251 million tons of trash the United States accumulates per year.
The goal of the UIC Recycling Program, empowered by the Illinois Solid Waste Management Act is to minimize waste by encouraging the conservation of resources. Our priorities, as a campus, are to:
Reduce the waste we produce by choosing materials wisely
Reuse what we have already by considering new roles for unwanted material
Recycle what must be thrown away, and minimize material bound for landfill
The Recycling Program, coordinated by the Office of Sustainability, collaborates with the Student Centers, Athletic Facilities, Campus Housing, and the Transportation Department to increase opportunities to recycle while raising awareness of environmental issues on campus.
In 2012, we recycled nearly 3,500 tons of paper, plastic, metal and glass with an overall recycling rate of 46%. Additionally, we saved over 42,000 trees by recycling- just in 2012 alone!
Please leave us a message via phone or email and we will respond to your request within 2 business days.
Watch how Joe Iosbaker, UIC Recycling Coordinator, explains the recycling system.
START WITH SMART MATERIALS
It begins when the materials available for use on campus are chosen based on compatibility within our recycling program. If an item (for example, Styrofoam cups) is provided for use on campus, it is everyone’s responsibility to ask why it was chosen in the first place.
EQUIPMENT MAKES IT EASY TO RECYCLE
The seven-gallon recycling containers and hanging “side saddles” are provided in offices. In the residence halls there is other equipment in individual rooms or common areas. Students, faculty, and office staff are expected to empty these when full. This means you must carry your trash and recyclables to nearby stations and separate them into the appropriate bins. Cardboard should be flattened and placed behind the hallway bins.
These Recycling Stations usually consist of three bins (Paper; Glass, Metal & Plastic; and Landfill) and are located at set intervals throughout hallways and larger common areas in most buildings, with easy access from deskside unit locations. Building Service Workers (BSWs) empty these stations regularly and move the contents to a central collection point.
UIC Building Service Workers & Transportation Department
Central Collection Points can be large dumpsters or smaller “totes” where recyclable materials from an entire building (or cluster of buildings) are stored; Recycling Truck drivers will empty these points during the week on a scheduled or as-needed basis.
Sorting & Processing
These organizations that collect or process material collected or hauled by UIC Recycling:
- Loop Paper Recycling, Inc. at 2401 S. Laflin receives sorts and processes paper, metals, plastics and glass from UIC.
- Recyclables are dumped on to the sorting floor and then spread out by a wheel loader
- The load is evaluated and given a grade of recyclable content
- Contents are then pushed by the wheel loader on to a conveyor belt
- Conveyor belt lifts the recyclable material to a elevated sorting system
- Elevated sorting system has 20 laborers (10 on each side) picking out the various commodities in the compactor load
- Underneath the elevated sorting system are collection bins with the various commodities that have been source separated
- The source separated commodities are then individually baled or processed.
- Each bale of paper weighs 1500 pounds!
- The bales or processed materials are then loaded on trailers to be transported to the recycling mills
- Mills receive trailer loads of baled and processed material. The baled material is then pulped and recycled into new paper commodities.
- Recycling Systems, Inc. gets our municipal solid waste. Their material recovery facility (MRF) is designed to accept and process commingled material. You can see the process in this video:
- Citadel is the largest of the shredding companies used by UIC departments. It has most of the contracts at UI Hospital & Health Sciences, taking the documents with patient information.
- Resource Center is a non-profit that hauls away the food scraps collected at our dining halls, and turns it into nutrient-packed compost used to grow delicious produce at their city farms.
Product to Shelf
The materials we recycle have a future! Each stream has its own markets, companies and products that are produced. See below where our materials get sent to and what they get turned in to.
Aluminum→ Anheiser Busch→ New Aluminum
Glass→ Strategic Materials→ New Glass
Metals→ General Iron→ Steel
Plastics→ Mega Max→ New Plastic
Plastics→ Mohawk Plastic→ Carpeting
Yardwaste/Compost→ Land and Lakes→ Mulch and Topsoil
Cardboard→ Bay Fiber Paper Mill→ Kraft Paper
White Paper→ International Paper→ Tissue Paper
Newspaper→ SP Newsprint→ Newspaper
Mixed Paper→ Georgia Pacific→ Bond Paper
- Loop Paper Recycling, Inc. at 2401 S. Laflin receives sorts and processes paper, metals, plastics and glass from UIC.
Most materials generated at UIC are recyclable and will have a second life! What makes a material “recyclable” is its structural components, as well as the status of the market of those materials. We have listed the most common materials that are recyclable on campus. If you have a question about a material not mentioned, please contact us.
Click on a tab to learn more about the different materials that are recyclable at UIC
LIST OF ACCEPTED MATERIALSPaper
- White and Colored Paper
- Glossy Paper
- Envelopes, including Window
- Newspapers and Magazines
- NCR (carbonless paper)
- Copy-Paper Ream Wrappers
- Post-it Notes
- Chip Board (e.g. tissue boxes)
- Brown Paper
- Hard-Bound Books
- Milk Cartons
No Need to Remove Paper Clips, Staples or Rubber Bands!
- Food and Food Wrappers
- Styrofoam and Paper Cups
- Tissue Paper and Paper Towels
- Plastic Bags
- Carbon Paper
- Photographic Paper
- Coated Fax Paper
- Plastic-Coated Paper (laminated)
- Tyvek Plastic Envelopes
- Mailing Envelopes with Plastic Padding
Cardboard should be flattened and placed behind the hallway bins. Dry, clean (covered with minimal food waste) cardboard is recyclable. Pizza boxes with little or no grease/food are acceptable.Glass, Metal, Plastic
- Aluminum Cans
- Steel Cans
- Plastic Bottles (numbers 1 to 5, and 7) what do these numbers mean?
- Glass Beverage Bottles (all colors)
- Aluminum Foil (not heavily soiled)
- Plastic Bags and Wrap
- Juice Boxes and Tetra Paks
- Non-hazardous, empty chemical bottles
- Lots of liquids in Bottles
- Styrofoam Cups and Packing
- Test Tubes and other contaminated laboratory glassware, including Pyrex
- Drinking Glasses
- Broken Glass
- Plastic Cutlery
All About Plastics
Many consumer products, such as water bottles and product containers, are made from various types of plastic. The Society of the Plastics Industry (SPI) established a classification system in 1988 to allow consumers and recyclers to properly recycle and dispose of different types of plastic. Manufacturers follow a coding system and place an SPI code, or number, on each plastic product, which is usually molded into the bottom. Although you should always verify the plastic classification number of each product you use, this guide provides a basic outline of the different plastic types associated with each code number.
Plastic marked with an SPI code of 1 is made with Polyethylene Terephthalate, which is also known as PETE or PET. Containers made from this plastic sometimes absorb odors and flavors from foods and drinks that are stored in them. Items made from this plastic are commonly recycled. PETE plastic is used to make many common household items like beverage bottles, medicine jars, peanut butter jars, combs, bean bags, and rope. Recycled PETE is used to make tote bags, carpet, fiberfill material in winter clothing, and more.
Plastic marked with an SPI code of 2 is made with High-Density Polyethylene, or HDPE. HDPE products are safe and they are not known to transmit any chemicals into foods or drinks. HDPE products are commonly recycled. Items made from this plastic include containers for milk, motor oil, shampoos and conditioners, soap bottles, detergents, and bleaches. Many toys are made from this plastic as well. (Please note: it is NEVER safe to reuse an HDPE bottle as a food or drink container if it didn’t originally contain food or drink!) Recycled HDPE is used to make plastic crates, plastic lumber, fencing, and more.
Plastic labeled with an SPI code of 3 is made with Polyvinyl Chloride, or PVC. PVC is not often recycled and it can be harmful if ingested. PVC is used for all kinds of pipes and tiles, but it’s most commonly found in plumbing pipes. This kind of plastic should not come in contact with food items. Recycled PVC is used to make flooring, mobile home skirting, and more.
Plastic marked with an SPI code of 4 is made with Low-Density Polyethylene, or LDPE. LDPE is not commonly recycled, but it is recyclable in certain areas. It is a very healthy plastic that tends to be both durable and flexible. Plastic cling wrap, sandwich bags, squeezable bottles, and plastic grocery bags are all made from LDPE. Recycled LDPE is used to make garbage cans, lumber, furniture, and more.
Plastic marked with an SPI code of 5 is made with Polypropylene, or PP. PP can be recycled. This type of plastic is strong and can usually withstand higher temperatures. Among many other products, it is used to make plastic diapers, Tupperware, margarine containers, yogurt boxes, syrup bottles, pipette tip boxes, prescription bottles, and some stadium cups. Plastic bottle caps are often made from PP as well. Recycled PP is used to make ice scrapers, rakes, battery cables, and more.
Plastic marked with an SPI code of 6 is made with Polystyrene, also known as PS and most commonly known as Styrofoam. It can be recycled, but it is difficult to do so and often ends up in landfills anyway. Disposable coffee cups, plastic food boxes, plastic cutlery, packing foam, and packing peanuts are made from PS. Recycled PS is used to make insulation, license plate frames, rulers, and more. At UIC, we cannot accept #6 plastics into our recycling program, and they must be disposed of in the landfill. We encourage the reuse of these plastics before disposal.
The SPI code of 7 is used to designate miscellaneous types of plastic that are not defined by the other six codes. Polycarbonate and Polylactide are included in this category. These types of plastics are difficult to recycle. Polycarbonate, or PC, is used in baby bottles, large water bottles (multiple-gallon capacity), compact discs, and medical storage containers. Recycled plastics in this category are used to make plastic lumber, among other products.
Consumers can make better plastic-purchasing decisions if they understand SPI codes and potential health hazards of each plastic, and recyclers can more effectively separate plastics into categories. Always check a product’s classification code prior to recycling it or re-using it. It’s important to stay educated about plastic classification numbers and plastic types; remember, informed consumers can demand that plastics manufacturers provide better products.Electronics
Campus Electronic Recycling Collection (CERC)
UIC recycles over 6,900 electronic items annually!
UIC recycles electronics separately from the normal recycling. Any equipment belonging to the university must be disposed of in accordance with the OBFS Equipment Disposal Methods. Additional information about the disposal of equipment as scrap or surplus can be found within the OBFS Equipment Management webpages. Questions may be directed to the Property Accounting & Reporting Office firstname.lastname@example.org or 312-996-2858.
However, at least once a year, the Office of Sustainability organizes a Campus Electronics Recycling Collection (CERC) Program that centralizes the collection. All you need to do is fill out the associated paperwork, bring your item, along with a hard copy printout of the Property Accounting approved FABWEB disposal request, and we take care of the rest! Typically, we host CERC twice each semester- once on East Campus, and one on West Campus. Check our events page to find when the next event will be!
Additional notes on equipment:
Toner CartridgesBoth campus bookstores will accept spent ink cartridges for recycling, and can refill spent cartridges for a fee. Visit or contact one of the bookstores to learn more.
- Data-containing devices sent to CRS are sanitized according to NIST 800-88 and Department of Defense standards
- A hard drive and a monitor must be listed separately, in case a department wants one and not the other.
- Cords, chargers, cables, keyboards and mice should be boxed together and listed separately from the hard drive or monitor. However, power supplies should remain with laptops.
- Data on hard drives must be overwritten or “scrubbed” and all equipment with a hard drive must be labeled with a “scrubbed” sticker. If not, then someone in Property Accounting will have to degauss.
- We recommend that you sanitize your hard disk drive prior to donating your device. If your device is running MS Windows, you can use Active@ ERASER 4.1 which is freely available via webstore.illinois.edu, or by clicking this direct link. If your device is running Mac OS you can use Disk Utility.
The UIC Copiers program and its partner, the Gordon Flesch Company, are committed to supporting UIC’s sustainability efforts. Faculty and staff may recycle used copier and printer toner cartridges from any manufacturer in two easy ways.
- Bring your used cartridges to the red drop-off bins on either side of campus:
- East Side – UIC Copy Center, 209 Student Center East (SCE)
- West Side -Used ink cartridges will need to be recycled by asking a staff member until further notice.
- If you are a UIC Copiers customer, have a Gordon Flesch service technician pick up used cartridges during routine maintenance calls.
For further information, call UIC Copiers at 6-3567 or write to email@example.com.
Drop Off for Cartridges:
All common cartridges may be dropped off at the following campus locations. Ask a staff member for assistance in dropping off.
For West Campus Cartridge Recycling:
Used ink cartridges will need to be recycled by asking a staff member until further notice.Pipette Tip Boxes
PIPETTE TIP BOXES
Print version: Pipette Recycling Flyer (1)
Starting in 2011, UIC began recycling #5 polypropylene plastic from pipette tip boxes, lids, and trays typically found in Life and Medical Science Laboratories. Pipette tip boxes are to be placed in the specially-marked bins near labs that use pipette tips. They will be recycled and eventually turned into other uses such as agricultural trays for plants. Please do not fill the bin greater than 75% full, as it makes it difficult for UIC Building Service Workers to handle the bag of recycling.
Please note that only #5 type polypropylene plastic from clean, uncontaminated pipette tip boxes, lids, and refillable trays will be accepted. No other lab plastic is accepted. UIC cannot accept pipette tips because they have the potential to puncture and tear open the bags and, more importantly, there is no guarantee that the tips are clean.
By their nature, boxes, lids, and trays are used to store clean plastic (like the tips) so they are inherently clean. Tips, on the other hand, are designed to contain chemicals and biological agents, and should be regarded as trash, or sometimes biohazardous waste. Even if the tips have never been used, they are still treated as trash. If a bag is found to have pipette tips or any other types of lab plastic (e.g. chemical bottles, centrifuge tubes, etc), the entire bag becomes trash.
Here are 3 simple steps you can follow and promote to make sure this program runs smoothly!
Currently, bins can be found scattered through the hallways of
- College of Medicine Research Building (COMRB)
- Medical Sciences Building (MSB)
- College of Medicine West Tower (CMWT)
- College of Medicine West (CMW)
- College of Medicine East (CME)
- Clinical Sciences North (CSN)
- Clinical Sciences Building (CSB)
- College of Pharmacy (PHARM)
- Molecular Biology Research Building (MBRB)
- Center for Structural Biology
- Applied Health Sciences Building (AHSB)
To request a bin in you building, please email firstname.lastname@example.org and tell us your building name and room number.Chemical Bottles
CHEMICAL BOTTLE RECYCLING
Chemical bottles may be recycled along with other glass/metal/plastic as long as it meets the following criteria:
- the bottle is empty (nothing will drip when inverted) Do NOT allow voltile liquids to evaporate in the fume hood as a method of disposal!
- the bottle is capless (unsealed/ opened)
- label is defaced (name of chemical is scratched out with a marker)
- the bottle used to contain non-hazardous materials (examples include media, buffer solutions, etc.)
Never recycle a bottle that used to contain flammable*, toxic, oxidizing, explosive, radioactive, water reactive, carcinogenic, biohazardous, or corrosive substances.
Please see the EHSO Lab Safety Plan how to identify a hazardous chemical and dispose of hazardous chemical bottles according to the Lab Safety Plan.*the only acceptable bottle to recycle that contained a flammable substance is ethanol.Office Furniture
OFFICE FURNITURE AND SURPLUS
Used, but useful, surplus equipment can be redistributed at the Laflin Warehouse Building, 1514 S Laflin St. The hours of operation are 8:00 a.m. – 4:00 p.m., Monday through Friday. You can call the warehouse staff at 996-2877. (Note: the campus shuttle bus does not go by the warehouse. Parking is available on Laflin Street by the front door). Please don’t call them for descriptions of available furniture; you need to visit the warehouse yourself to look over the inventory.
KEEP UNWANTED MATERIAL OUT OF LANDFILLS
To dispose of unwanted furniture or equipment, start at the OBFS website. You will find the “Request to Dispose of Equipment as Scrap or Surplus” form. Complete and submit the form to email@example.com. The Property Accounting Office will review the form for completeness and return it to you. You are to contact Facilities Management Transportation to schedule a pick-up of the items for delivery to the warehouse if usable (surplus). Equipment no longer usable (scrap) will be properly disposed in accordance with campus policy.
RECLAIM USEFUL FURNITURE
An ever changing inventory of computers, monitors, tables, chairs, desks, file cabinets, and shelving is available for transfer to university departments/units. This equipment cannot be redirected for personal and must be used solely for university business.
The transfer process begins by going to the OBFS website to find the form, “Interdepartmental Transfer of Equipment”. Complete the form and submit it to the Property Accounting Office by emailing it to firstname.lastname@example.org. Property Accounting will review the transfer and direct you to contact the FM transportation for a work order to schedule the pick-up and delivery of the equipment to your facility.
You can also call the UIC Property Accounting Office at 996-2858 for more information about the process for redistribution or disposal of university equipment.Plastic Bags and Film
Plastic Bags and Film
UIC now accepts plastic bags. Create a separate bin for your plastic bags and UIC will recycle them. We do not accept plastic bags and film in the normal recycling containers (they will “gunk up” the machines at the recycling facility) but we are happy to take them as long as they are separated.
- dry cleaning and newspaper bags
- bread and produce bags
- beverage case wrapping
- paper towel wrap
- bubble wrap and air pillows
- plastic grocery bags
However, your home recycling may not accept plastic bags. Did you know that there are more than 18,000 retail locations where you can recycle plastic bags? Watch how plastic bags and film are processed for recycling into new products like plastic lumber on a porch or a bench in the park.
Where to recycle: Local retailers and grocery stores. Find one here.
Here’s a handy reminder for your fridge! Print and Cut Out for Yourself and a Friend
Learn more about plastic bag and film recycling: I Want To Be Recycled campaign.Food Scraps
FOOD SCRAP COMPOSTING
UIC has a program that composts your food scraps and plate waste. Although you won’t see bins where you can scrape your scraps into, UIC composts behind the scenes.
Visit one of the All-You-Care-To-Eat dining halls in Student Center East or Student Center West to see how composting transforms your left-over food scraps into re-usable, nutrient rich soil. See here to get a better understand of what composting is and why it’s an important sustainability practice!Writing Utensils
Starting in 2011, UIC has participated in a Terracycle Brigade to collect and recycle used writing utensils. The student group, EcoCampus has ben instrumental* in making this program a success! In Fall 2014, UIC sent over 32 pounds of used writing instruments to be recycled into products like plastic storage bins.
Drop off your used writing instruments at the Daley Library!
- Pens and pen caps
- Mechanical pencils
- Markers and marker caps
- Permanent markets and permanent marker caps
*pun definitely intended
Daley Libraryall other materials
ALL OTHER MATERIALS
Materials unlisted on this page may not be compatible with existing UIC Recycling services. To find out the best place to recycle something not listed above, check Earth911.com
What about coffee cups?
Coffee cups are tricky, because even though they are made from paper, they may contain a plastic or wax coating that makes them undesirable to recycle. However, parts of the to-go coffee cups may be recycled. The paper sleeve can be recycled int eh paper recycling bin and the plastic lid may be recycled IF the lid is a #5 plastic. Unfortunately, most to-go coffee cup lids are #6 PS and must be thrown in the trash.Items that cannot be recycled
Great Stuff Exchange at the UIC Free Store
We can all promote reuse and source reduction as alternatives to recycling and smart, viable actions for any person or department to take. Reuse also saves your department and the university valuable resources. All materials are free to anyone at UIC.
There are 2 ways to donate/receive free office supplies
1) GSX event in September
The Great Stuff Exchange (GSX) is an annual event on that occurs once each fall in the West Concourse of Student Center East (750 S Halsted Street). Check out pictures from our GSX event from April 2013
2) UIC Free Store
You can bring materials, like the ones listed below, to the Office of Sustainability at 150 PSB anytime. Please contact Joe Iosbaker at email@example.com or at 312-413-9816 first to make sure someone will be in the office to receive your stuff.
Come shopping! Our inventory is updated constantly, so come over and check out what we have! (Pictures coming soon!)
Office of Sustainability Free Store
- Appointment Books & Calendars
- Binders, Notebooks & Paper
- Bookends & Vertical Files
- CD’s, DVD’s, Jewel Cases
- Desktop/Mouse Pads & Organizers
- Drawer Organizers
- Envelopes & File Folders
- Unused Greeting Cards
- Name Tag Holders
- Rolodex Boxes & Cards, Index Cards
- Scissors, Staplers, & Hole Punchers
- Pens, Pencils, Lead, & Ink Refills, Toner Cartridges
- Report Covers & Sheet Protectors
- Storage Boxes, Cases, Files & Racks
- Clothing, Shoes, & Furniture
- Hazardous Wastes
- Large Equipment
- Household Items
- Anything with a University “PTag”
- Broken items
GUIDELINES & LIMITATIONS
- All donated items must be clean and in working condition.
- The value of any donated item may not exceed $100.
- Inkject, laser, fax and copier toner cartridges are acceptable – OEM only, not refurbished.
- Furniture, computers, and larger or more expensive office equipment can be advertised at the Surplus Station.
To donate items either at the Great Stuff Exchange or at the Free Store, please fill out the form. Any and all information is greatly appreciated!
The Office of Sustainability has recently started to collect lab supplies from labs that no longer need them. Please come see our inventory at the Office of Sustainability LabShare store, room 150 Paulina Street Building, 1140 S. Paulina St. The store is accessible when staff are present in the office. Please call ahead to confirm 312-413-9816.
UIC LabShare Store
Come shopping! Our inventory is updated constantly, so come over and check out what we have! Examples of items include:
- Serological Pipettes
- Erlenmyer Flasks (various sizes)
- Beakers (various sizes)
- Graduated Cylinders (various sizes)
- Test Tubes
- Slide Boxes
- Culture Plates & Grids
- Culture Tubes
- Aprons & Scrubs
- Pyrex Tubes
- Pipette Tips
- Caps & Stoppers
- and much more!
Thank you for donating to the UIC LabShare program. We can take usable laboratory supplies such as glassware, disposable items, and equipment. Please note that we cannot accept any broken items, equipment with “PTags” or hazardous items. Broken lab glass must be sent to the landfill, PTag items should be processed through UIC Property Accounting, and hazardous waste should be disposed of through the Environmental Health and Safety Office*.
*See the UIC Environmental Health and Safety Office guideline for Biohazard Waste Disposal for disposing laboratory glass (Yes, even non-biohazardous materials are referenced here.)
The UIC Recycling Program collects data on many of the campus waste streams, including recycled paper, cardboard, glass, metal, plastics, and waste that goes to landfill. The data is used to calculate a recycling rate, which is the total amount of recycled material divided by the total amount of waste generated by the university.
The Office of Sustainability is undergoing a project to upgrade how recycling information is collected and reported. When the project is complete, this page will include information about recycling at the building level. Check back soon to find out how much material is recycled in your building!
Wondering about a specific building? Contact us with a specific question and we’ll do our best to get you an answer.
*Infectious waste from the UIC Medical Center is not included, since the treatment process is different from ordinary waste. Open-top containers are also not included because they often contain construction debris. However, the City of Chicago’s Construction & Demolition Ordinance requires that at least 50% of the construction or demolition debris generated on a job site is recycled!
Both these exclusions conform with guidelines from the National Recycling Coalition.
UIC Food Scrap Composting
UIC has a program that composts your food scraps and plate waste. Visit one of the All-You-Care-To-Eat dining halls in Student Center East or Student Center West to see how composting transforms your left-over food scraps into re-usable, nutrient rich soil. See below to get a better understand of what composting is and why it’s an important sustainability practice!
What is composting?
Composting is the process of repurposing organic materials such as vegetable scraps, egg shells, wood chips, manures, grass clippings, fruit peels, newspapers, and many others, into rich, productive soil. It is a process that saves hundreds of pounds of harmful greenhouse gas emitting waste from entering and filling up our landfills
Food scrap composting at UIC
In 2013, UIC Student Centers, through the help of the Illinois Department of Commerce and Economic Opportunity, implemented back-of-the-house food scrap and plate waste composting at the All-You-Care-To-Eat dining halls in Student Center East or Student Center West. This was made possible after an audit of food scrap collection revealed the amounts of waste that were being sent to the landfill, when they could have been reused! Today food scrap and plate waste composting are a successful practice in the UIC Student Centers.
Why is composting important?
In nature there is no such thing as “waste!” A “closed loop” cycle of material occurs where things such as plants, animals and other organic matter are left to decompose naturally. When the cycle is complete, nature takes its course and returns all the vitamins and nutrients to the Earth. This process enriches our planet by repurposing our food waste into rich organic soil that farmers and gardeners can re-use. The process also removes impurities naturally and helps reduce carbon emissions.
This allows the opportunity for new things to grow and live. Without composting, materials often sit in a landfill for years, producing harmful methane gas that destroys our atmosphere. In 2009, methane emissions from landfills made up 17% of total methane emissions in the US, the 3rd highest behind Natural Gas Systems (like power plants, home heating units, etc.)