Aug 24, 2010
The MIT SENSEable Lab is following trash from the home to the landfill. This is why you should care.
Do you know where your trash goes after you put it at the curb? If not, then you are in good company. According to a 2006 poll reported by the Massachusetts Department of Environmental Protection, about 1 in 3 US citizens do not know either. Every week, the average American disposes of 32.34 pounds of refuse and he or she has very little idea of what happens next; waste is a distant abstraction to most.
Why is this a problem?
Because 54% of the anthropogenic waste that Americans generate goes to landfills, which take up real estate, release toxins into the local environment through methane and leachate, and prematurely entomb useful resources that could be recycled, reused, or converted to another valuable product.
Fighting Lack of Awareness with Information
Within the SENSEable Lab is a group of individuals seeking to make people and businesses feel greater ownership of the waste they generate. They are known as the MIT Trash Trackers. Their theory is that if individuals knew the routes, methods, carbon footprints, and quantity of transported trash, they might think twice about buying a “#6 plastic” over a “#1 plastic”.
Much like a consumer follows a shipment from Amazon.com to their doorstep, the Trash Trackers want to follow trash from disposal to the landfill (or other destination). To achieve this, they set out and attached over 5,000 digital sensors (a.k.a. tags) to various articles of waste in New York City and Seattle.
On their journey, the tags transmit geographic coordinates and time record. Researchers then combine this data with contextual information to determine who transported the article, which transfer stations were visited, by what means the article was transported, and more. After three iterations of the tracking (two sets of experiments in Seattle and one in NYC), the Trash Trackers reached some conclusions.
1) Refuse collected in “Recycle Here” bins in NYC was not always recycled as advertised
2) Single Stream Recycling works… but oftentimes items are not processed appropriately
3) Seattle expressed more interest in the Trash Track project and its results than NYC
While not altogether enlightening, these generalizations just scratch the surface. Underneath the surface lie scrupulous details that reveal the inner workings of a recondite waste removal system that is detached from the day-to-day reality of most people. The question is, once the Trash Trackers process all the data, what does the world do with it?
The obvious first step would be for companies such as Waste Management, Inc. (a sponsor of Trash Track) or Republic Services to analyze the information and improve their waste management process. Or perhaps this project will launch new innovations in the sensor market producing sensors that are more durable, longer lasting, and can withstand the force of a garbage truck. But if we dig a little deeper, one can find some very interesting opportunities buried in the trash… Let’s take a look at some trends.
254 million tons of municipal solid waste (MSW) was generated in the US in 2008. Of that, only 22.1 million tons was composted. There is economic value in composting. The process creates fertilizers, soil additives, and pesticides by naturally decomposing organic matter. Each of these byproducts can be sold to farmers and landscapers for use in agricultural applications. Unfortunately, in an industrialized economy such as the U.S., agriculture as a percent of Gross Domestic Product is very low (1.2%). More importantly, the number of farms in the US has decreased drastically over the last 100 years.
Composting: Anaerobic Digestion While the market for fertilizers is large, it is not growing. Consequently, resourceful scientists and entrepreneurs have found alternate processes to convert organic waste into valuable products. One example is anaerobic digestion.
Anaerobic digestion is a “series of processes in which microorganisms break down biodegradable material in the absence of oxygen”. The outputs of anaerobic digestion include biogas and fertilizer. The fertilizer serves the same markets as typical composting, but the biogas, composed mostly of methane, can be burned as a source of energy.
Of particular interest is the distributed nature of anaerobic digestion. While anaerobic digestion plants require a significant capital outlay, the capital requirements are considerably less than a coal-fired or oil-burning power plant. What is more, organic waste is everywhere. All types of wood waste, food waste, animal waste, and even sewage wastewater (a product of every town) can be used in anaerobic digestion. Imagine an anaerobic digestion plant in every town or county in America that handles these wastes. The produced biogas could then be used to heat homes and pools, fuel gas stoves and many other applications not yet considered. A company currently using anaerobic digestion technologies is Harvest Power.
Harvest Power, based in Waltham, MA, builds, owns and operates facilities to turn yard clippings and other organic waste into biogas, compressed natural gas, and composted soil. To date, they have raised $40 million in financing and are planning to build North America’s first commercial scale high solids anaerobic digestion facility in Vancouver, British Columbia. The Vancouver site will process 30,000 tons of organic waste per year. Over the course of the next 4-6 years, the company envisions 50 facilities in North America. 
While the benefits of anaerobic digestion are clear, one of the main drawbacks is that the process is relatively inflexible to the types of inputs it can process. Therefore, the process requires a set of inputs that is accessible and of reliable composition.
The US has over 2,000 municipal solid waste, 1,370 industrial, and 1,889 construction and demolition waste landfills. These facilities bury over 370 million tons of waste per year. Over a 50 year period, the waste will decompose in the landfill, releasing carbon dioxide (CO2) and methane (CH4) in the process. In some cases, these gases are captured and burned to create energy. A three million ton landfill can create enough gas to produce approximately two megawatts of energy. However, only a small overall percentage of anthropogenic CH4 is captured and the CH4 that is not captured is about 22 times more destructive to the environment than CO2. Additionally, landfills release harmful leachate that can get into the water supply and soil, poisoning living organisms. The process for decomposing waste in a landfill is notably inefficient. This process can take over 50 years to complete and is environmentally destructive. As a result, technologies such as gasification have emerged as alternatives to landfills.
Landfill Alternative: Gasification
Gasification converts organic material into a synthesis gas, also known as ‘syngas’. This gas can be burned to generate heat and power (like natural gas), converted into a fuel (like methanol or hydrogen), or can be used to produce chemical intermediaries for plastics. The gasification process takes a matter of seconds to break down the waste stream, which is dramatically shorter than the 50 years for a landfill! Gasification is both more efficient than landfills, and produces higher value end-products. Consequently, makers of syngas have access to large and growing market.
According to the Energy Research Center of the Netherlands, the worldwide market for syngas is expected to expand by roughly 800% over the next 30 years.Interestingly, the quality of syngas depends significantly on the inputs to the gasification process. While gasification can handle a wide array of inputs ranging from plastics to biomass, the combination of various inputs will affect the quality of the syngas. The quality of the syngas, in turn, affects the type of end-product that can be produced. For instance, a low quality syngas could be burned in a boiler for heat, but it could not be converted into a chemical intermediate—which would require a high quality syngas.
An example of a company using gasification technology is Boston-based Ze-gen.
Ze-gen is using a liquid-metal gasification technology to convert various waste streams into syngas. They are currently raising money to build their first commercial-scale facility in Attleboro, MA and expect to generate revenues from the facility by 2012. The facility is designed to handle several types of inputs and produce up to 7 MW of power.  Ze-gen’s overall goal is to have distributed small plants in many locations across the world to aid in the conversion of waste to useful byproducts. Ultimately, Ze-gen predicts its syngas could be of a high enough quality that it could produce a liquid fuel to power an automobile. (Seems awfully reminiscent of Back to the Future, doesn’t it?)
One of the key challenges facing technologies like Ze-gen’s, however, is secure access to predictable waste streams in order to assure the quality of syngas for their end-products.
So what’s the hold up?
With the new highly efficient technologies currently available, what’s stopping these companies from rolling out? For starters, there are financial concerns, business model challenges, and governmental policy uncertainties. But there is also the trouble of finding and securing a steady stream of high-quality waste to serve as inputs to their conversion process. The most readily available and abundant type of waste is MSW; however, it is also highly “contaminated” with toxins and other materials that could hamper the conversion process.
MIT Trash Track to the Rescue
With the data emanating from the MIT Trash Track, there will be ample opportunity to analyze the traffic patterns of different types of trash. This information could inform government policy to improve the waste management system. It could also create an incentive structure to source separate MSW. Once separated, the different buckets of MSW could be moved to the local Harvest and Ze-gen facilities to be processed to heat your house, cook your food, and power your car. By encouraging awareness around how and where trash is moved, we can positively change how it affects our environment and how we power our lives. The MIT Trash Trackers might just be ready to spark a game-changing environment for entrepreneurs and the planet.
What do you think? Do you see other entrepreneurial opportunities that we might have missed? Please chime in the comments section below—we’d love to hear your thoughts.
 US Environmental Protection Agency < http://www.epa.gov/lmop/basic-info/index.html>; page 4, <http://www.epa.gov/wastes/hazard/generation/sqg/list/lfillpdf.pdf>