Wasting in the Energy Descent: An Outline for the Future

by Tom Shelley

Introduction

Our current growth-based economic view is based on the continuous and ever-increasing use of energy and resources. This process generates solid waste, pollution, and greenhouse gases in enormous quantities. Despite international efforts to reduce waste, the amount generated continues to grow.

Eventually we will hit a collective wall, the bricks of which will be environmental degradation, climate change disasters, and the peaking of many resources. Properly prepared communities will handle the triple crises of environment, energy, and economy better than those that are not. Dealing with our wastes in a more sustainable manner will help to ensure our survival in an energy- and resource-constrained future.

In fact, if we radically reorient our world view, we can live in a world of little or no waste. Biomimicry — following the designs of nature and the paths of indigenous peoples — can create a nearly waste-free economy. In an ideal world, as in nature, there would be no wastes, only re-purposed resources.

Our present system of domestic waste disposal, in which we make it “go away” by putting it on a truck and driving it to the landfill, is resource intensive. Picking up waste, processing it (including recycling), and hauling off the landfilled wastes and the recycled materials requires lots of energy, mostly in the form of fossil fuels or electricity generated from fossil fuels. The same is true for the treatment of sewage, animal wastes, and various industrial wastes. Fortunately, our diminishing consumption will mean a lot less waste.[1] Even if we follow the path of biomimicry, we will still be left, as we always have been, with an irreducible minimum that must be disposed of for various reasons. The following sections address specific waste streams and some alternatives for managing each one as individuals and as a community. Due to space limitations, this article is more of an outline than a treatise, and many questions are posed for which there are currently few, if any, answers. Hopefully, the answers will follow from our ingenuity at doing more with less as energy descent unfolds.

Human waste and domestic animal waste

Human bodily waste, and that of our animals, would quickly create a serious problem if it were not dealt with properly. In the urban setting, our current method of mixing body wastes with large amounts of expensive, purified drinking water, then re-purifying the water and returning it to the original water source is not a sustainable use of water, energy, or energy-intensive chemical resources. Sewage disposal in suburban and rural areas places an additional strain on resources and the environment. Many unanswered questions arise when considering urban waste disposal:

Infrastructure. What is the age and life expectancy of the current sewer and septic systems? What are the expected maintenance requirements and fossil fuel dependencies of repair and replacement materials? Will the required materials even be available in the future?

City sewers. How much energy does it take to run the City of Ithaca's sewage and treatment system? Can we reduce that cost? Can sewage treatment inputs be reconfigured to yield organic manures for local farming without contaminating sewage sludge? How long can the current systems be sustained on emergency power? Can emergency or even long-term power be supplied from local, City-owned hydropower? Can currently flared methane be used to heat greenhouses or for other heat recovery uses?

Septic systems. Many people in Tompkins County depend on septic systems that need periodic cleaning. Local septic tank cleaning firms now take their “product” to the Ithaca Area Wastewater Treatment Plant for processing. How will we manage this waste with less energy for transport? Will high costs of energy interfere with the processing load on the wastewater treatment plant if the volume of septic system effluent grows dramatically with population growth in areas not served by the plant itself? If this happens, what can we do about it? Will septic systems as we know them need to be phased out or abandoned in favor of other systems? Could we develop local or district sewage-to-methane facilities to relocalize the energy needed for heat and hot water using pumped septic tank effluent?

Sustainable waste treatment systems. Some experts believe that the way to approach sewage treatment is to stop using large amounts of water to process human waste and instead figure out ways to process it that yield fertilizer. Such an approach would reduce the energy consumed in the sewage treatment process; the chemical inputs, especially chlorine; and the need to maintain an extensive above ground and underground infrastructure. What would an alternative system look like? How much would such a system actually cost? Could it be deployed on a mass basis? How much will services deteriorate before local residents can be convinced to pay for and use alternative systems? Would more localized, small-scale processing be more energy efficient and cost effective?

Examples of human waste disposal[2]

Household scale: Small scale, aerobic, above ground composting (out of doors) with other organic materials could completely eliminate the septic tank system in rural and suburban areas. Most or all of the inputs are free, and there is no energy input other than human labor.[3] Dry and wet composting toilets provide an excellent solution in more densely populated areas, although they can be expensive and in some installations still require energy inputs. Many different commercial models are manufactured, and plans for homemade units are available. Envirolet is one popular commercial firm.[4] There are some manufacturers whose products reclaim water as well as make compost. Healthyhouse is an example.[5] Properly composted human waste can be used for general purpose gardening, as it has been for thousands of years, but for safety reasons many composters believe that it is only suitable for orchards, field crops for domestic animals, etc. Human urine[6] can go into greywater systems (see below) or compost piles, and it can be directly applied to vegetable crops as a fertilizer, since it is “clean” and provides carbon, nitrogen, and other essential elements for plant nutrition. See Liquid Gold for details.[7]

Urban scale: The aerated sewage sludge from human wastes is composted and used on food and field crops in many urban areas. Even a city as far north as Fairbanks, Alaska, composts all of its sewage sludge all year round. In Sweden, many communities collect human urine on a large scale and use it to fertilize field crops. Methane generated by the sewage treatment process or anaerobic digestion of human sewage is used to produce heat and hot water and the co-generation of significant amounts of electricity. The local sewage treatment plant uses about half of the gas it produces to generate some of the electricity that powers the plant. The plant’s operation is detailed on the City of Ithaca’s web site.[8]

Human wastes can be processed on a small scale to provide biogas for heating and co-generation of electricity (district heating) for a neighborhood or small village. We could heat our homes and read by the light generated by our own wastes. The solid byproducts would be further composted and used to grow the food we eat. Although not based on human wastes, the plan developed for Linden Hills, Minnesota, explores some of the possibilities.[9]

Examples of water reuse

Household or neighborhood: Greywater is the waste water from any household source except toilets. Greywater systems most frequently take the form of artificial wetlands, although there are many other designs. This reuse of lightly used water from sinks, showers, or the laundry uses little or no energy and can remove a tremendous burden from our current home wastewater treatment systems. At the same time, the biological cleansing and oxygenation provided by an artificial wetland can purify this lightly contaminated domestic water and return it to beneficial use, such as watering gardens. Greywater systems are easy to build and maintain and can be constructed to serve multiple households or small villages. For examples, see Art Ludwig’s Create an Oasis with Greywater.[10]

Urban scale: Large-scale greywater systems using artificial wetlands have already been developed in some urban areas. Some large-scale indoor systems using greenhouses have been developed as well. Reports from Australia and China detail large-scale greywater use.[11][12]

Using a combination of the above methods, we could process all human bodily wastes in a beneficial manner, using comparatively little energy, and eliminate the need for traditional sewage treatment systems.

Special Materials

Dog waste can be processed in the same way as human waste. A composting project in Montréal at a single public dog run diverted over a ton of dog waste and at least 7000 plastic bags from the city’s landfill.[13]

Cat waste carries more pathogenic bacteria, and when mixed with clay-based kitty litter, it is especially difficult to process in alternative systems. Using cellulose-based litter (wood shavings, processed newspaper, or other biowastes) or wheat-based or other compostable materials allows cat litter to be composted. However, the compost may only be used on non-food crops.[14]

Fiber-based diapers, with little or no plastic used in their manufacture, can be composted commercially. Cloth diapers can be used repeatedly.

Feminine hygiene products and other materials contaminated with human blood or other body fluids, usually landfilled or processed by the Publicly Owned Treatment Works (POTW), may be compostable, depending upon composition and circumstances.

Hospital waste streams, both human and veterinary, are often difficult to handle due to their content of tissues, body fluids, plastics, radioisotopes, antibiotics, and various drugs. Incineration is the most often used disposal method along with various alternatives, such as alkali decomposition, autoclaving, etc. all of which are extremely resource and energy intensive. Any fiber-based materials may be composted in a commercial compost system.

Food waste, lawn debris, and other organic waste

Composting. Along with many paper items, 100 percent of home and restaurant food wastes can be composted. This would further reduce energy consumed in traditional waste processing, provide additional jobs, and generate soil amendments for organic gardens, at the same time reducing greenhouse gas emissions. Composting may be undertaken year round in commercial facilities. If done in greenhouses, it can be used to generate heat. “Lawn waste” of all kinds can be composted into mulch. Animal bedding can be composted with plant remains, as is done at Cornell University. Some animal manures, such as chicken waste, can be either composted or turned directly into garden soil. Composting will have an increasingly important role in our energy- and resource-constrained future. For local sources of composting information, see the Cornell Cooperative Extension Compost Education Program[15] and Cornell Composting.[16] Cayuga Compost runs an excellent local commercial composting operation.[17]

Vermiculture. A rich compost can be made using small red worms as the main decomposing organisms. Vermiculture can be done inside during the winter, which is an advantage over most small home composting setups. It is even undertaken on a commercial scale.[18]

Chickens. Many kinds of food waste and composted food wastes can be fed to chickens, which in turn produce valuable fertilizer and eggs. Chickens eat garden pests and weeds as well. Interest is growing in allowing small numbers of chickens (hens) to be kept in the urban/suburban environment.[19]

Other types of solid waste

Recycled materials. Increased recycling of a wide variety of materials could reduce Tompkins County’s energy requirements and our greenhouse gas emissions. It would be desirable to develop local recycling-based industries that use materials discarded in the County. As the cost of transporting materials grows, opportunities for “green” business development based on recycling and reuse will also grow. Tompkins County Solid Waste Division, an operation funded mostly by the County, already has one of the highest diversion rates in the U.S., nearly 60 percent. A wide variety of materials are taken for recycling in addition to the usual glass bottles, paper, newsprint, cardboard, and metal cans, including many fiber items, aseptic packaging, beverage cartons, clothing, and used motor oil.[20] However, there are still many materials that aren’t recycled or for which we could do a better job. For example, while most large supermarkets take back the plastic bags they dispense, most types of plastic packaging and other plastic items that are not bottles or food tubs still go to the landfill. Plastic waste is now a significant component of the average family’s non-recycled waste stream. Metals are a special case: there are traditional local purchasers of discarded metal plumbing components, roofing, structural steel, wire and cables, car parts, appliances, etc.

Some materials have new markets due to the energy and greenhouse gas crises. Used cooking oil, for example, is now strained and used directly for motor vehicle fuel in converted engines. Vegpower[21] and Liquid Solar[22] are local examples. Used oil can also be converted into biodiesel and used in conventional diesel engines, as shown by Ithaca Biodiesel.[23] Such local sources of carbon based fuels will become increasingly important in the future. These products still produce greenhouse gases, but they are less polluting than traditional fossil fuels overall.

"ICI" (institutional-commercial-industrial) is a specialized set of waste streams that can be recycled in bulk (metal turnings, plastic trimmings, packaging films, etc.) but not in traditional municipal solid waste systems. In our area, most of these materials must be transported to an urban market to find a buyer, often at an expense more than the value of the material to be recycled. These materials often end up in a landfill. IMEX, sponsored by the City of Seattle, is an example of a government-sponsored urban industrial materials exchange.[24]

Special Materials

Hazardous waste: Some spent hazardous materials can be locally processed or reused; for example, solvents can be distilled and used again. Strict state and federal regulations govern hazardous waste reuse. The Tompkins County Solid Waste Division hosts a very successful household hazardous waste program.[25]

Construction debris: The byproducts of construction and demolition are among the largest components of the municipal waste steam. Wood, sheetrock, masonry, and metal elements are heavy are and generated in large quantities.[26] Some of these materials, especially metals, have traditionally been recycled. Large volumes of other materials have usually gone directly to the landfill. In recent years, with the increased cost of construction materials outstripping the increased cost of other materials by a wide margin, many other items are now reused or recycled. Old concrete is crushed and reused as aggregate; asphalt paving is milled, reconditioned and repaved; sheetrock is processed into an agricultural amendment; wood is shredded on site and used as mulch. In the future, fewer construction materials will be headed for the landfill.

Composite materials: Carpeting, mattresses, furniture, car and truck seats, and other composite materials are now increasingly recycled, mostly on an industrial scale.

Glass: Many kinds of glass cannot be reused to make containers or other items. Non-recyclable glass can be ground and used as filler in bricks and as aggregate in concrete and paving materials.

Batteries: Alkaline batteries can be broken down into their components and almost 100% recycled. All other types of batteries, especially lead-acid car batteries, can be recycled.

Fluorescent bulbs: Fluorescent bulbs of all kinds, along with some other specialty bulbs and light sources, should be recycled due to the mercury and other toxic elements they contain. Ordinary incandescent bulbs can be recycled for all of their components.

Plastics: Plastics that are not recycled in traditional residential curbside programs are increasingly recycled as plastic lumber, aggregate for concrete, and other products.

E-Waste: Computers, cell phones, and other electronics can be increasingly recycled or reused. Take-back programs are now more common and effective and, in some instances, are mandated by state and local governments.

Freon: Many freons are severe ozone depleting chemicals, and their disposal is heavily regulated by the Federal and state governments. The Tompkins County Solid Waste Division charges $20 to remove the freon from air conditioners, refrigerators, freezers, and other equipment.

Reuse centers: Thousands of consumer items can be successfully repaired, cleaned up and recirculated back into the community instead of being recycled (down-cycled in many cases) or discarded in a landfill. This process really saves energy and dwindling resources of all kinds, limits the emissions of greenhouse and hazardous wastes, and generates jobs. As we prepare for energy descent, generic or specialized reuse centers will become central to our communities. Some local examples are:

Finger Lakes ReUse, Inc. This newly formed organization accepts used and surplus building materials, furniture, housewares, electronics, art and school supplies, and more for resale.[27]

Significant Elements promotes the reuse of architectural elements.[28]

RIBS recycles bicycles and offers bike repair classes.[29]

Friends of the Library recycles books and various non-print media.[30]

SewGreen resells fabric, sewing machines, and sewing supplies and promotes sustainability in fiber, fabric, and fashion.[31]

There are also numerous used goods stores that promote the reuse of a wide variety of consumer items.

Freecycle: This is an electronic (mailing list-based) materials and consumer products recycling and reuse program that is completely free and has wide popular support. Ithaca Freecycle[32] is a local branch of an international organization. Its only goal is to keep materials out of the landfill. As long as the internet or local networks survive, this forum will be an important part of our community's materials exchange.

Farm animal wastes: Since a mass transition to a vegan lifestyle does not appear imminent, the long-term handling and processing of farm animal wastes will be a substantial issue for the county and region. Ideally, all small-scale farm animal wastes will be composted or spread directly on productive farm land to return valuable nutrients to the land. Some animal wastes — rabbit and chicken droppings, for example — are composted and sold as garden fertilizer. For large-scale “factory” farming this is not an immediate option. Energy descent will eventually make such operations uneconomical, but in the meantime the waste disposal from factory farms must be handled appropriately to prevent environmental contamination. Although factory farm waste processing is heavily regulated in most states, it is still a major environmental concern in some local towns. In most instances, appropriate handling of large-scale animal waste streams can provide cost-effective benefits such as co-generated electricity and methane production for heating farm water and greenhouses.

Storm Water: Although not a “waste” in the usual sense, runoff rain water is often contaminated with a wide variety of hazardous or undesirable materials: animal wastes, fertilizer, pesticides from farming and domestic sources, petroleum products from vehicles, sunscreen and other topical applications from humans and pets, a wide range of pharmaceuticals and antibiotics from human and veterinary use, copper and lead from roofing materials and gutter systems, and many other materials. Much storm water gets treated in publicly owned water treatment works, and some goes directly into bodies of water. Water from roofs can be collected and used to water gardens; properly collected and purified, it can be used for human consumption if necessary. Much work needs to be done to conserve and utilize this valuable resource.

Conclusion

The long-term goal should be to achieve “Zero Waste” while expending as little energy as possible and ensuring that little or no residue goes to long-term in-ground storage, the air, or a body of water. Incineration, even to generate electricity, should be avoided at all costs, as it destroys valuable resources, severely contaminates the air, and produces massive quantities of greenhouse gases. Manufacturers must be required to reduce packaging, especially petroleum based plastics, and take back products or their components that can’t be reused or recycled locally. Composting, recycling, reuse, and repurchasing programs must be generated to cover all of our resources. When energy and resources are scarce or no longer attainable, nothing will go to waste.