Did you know that two tons of waste is equal to one ton of coal? And four tons of waste equals one ton of oil? Converting waste to energy is one of the most effective ways to reduce harmful carbon emissions and decrease our nation’s dependence on fossil fuels.
Waste-to-energy (or energy-from-waste) is the method of collecting municipal solid waste and turning it into useful heat and electricity. This ecological method works by burning waste at a high temperature and then using the heat to make steam – similar to how a coal-fired plant makes electricity. The process not only creates energy from garbage, but it reduces the volume of trash that ends up in a landfill.
The Waste-to-Energy Process
Municipal solid waste contains biomass and biogenic products, like paper, food waste, grass clippings, leaves, etc. There are also materials made from non-biomass combustible materials like plastics and synthetic petroleum-derived products. Noncombustible materials make up the rest: glass and metals that make their way to the landfill.
All of these energy-rich materials are dumped from garbage trucks into a large pit, where a crane grabs the trash and dumps it into a combustion chamber. The most common method used, the mass-burn system, involves a large incinerator with a broiler and generator. Once the waste is burned, it releases heat that turns water into high-pressure steam in the broiler. Finally, the steam turns the blades of a turbine generator and electricity is produced.
What about air pollution? A carefully designed air pollution system removes toxic particles from the combustion gas before it’s released through the smokestack and turns them into ash. In fact, the Environmental Protection Agency (EPA) reveals that once the gas steam travels through the filtration system, more than 99 percent of particulate matter is removed.
Of every 100 tons of waste that’s turned to energy, about 5 to 15 of the volume is left behind as ash byproduct. The ash particles fall into receptacles and are carefully transported to a special landfill designed to prevent potential groundwater contamination. The ash residue may be further processed to remove the scrap metal, and can even be used in composts and fertilizers, depending on the material burned.
Waste-to-Energy Facilities in the U.S.
Today, there are 75 waste-to-energy facilities in the U.S., located mostly in Florida and the Northeast. That number is down from 87 about a decade ago, but the industry seems to be making a comeback. In Europe, burning trash to create electricity is a booming industry, but the United States has been slower to adopt, thanks in part to regulations, economic constraints and even anti-burn activists.
In 2015, after a decade in the making, a new commercial waste-to-energy facility opened in Palm Beach County, Fla. The $672 million mass-burn plant was the first to be built in North America in more than 15 years. Dubbed the “most advanced facility of its kind in the world today” the plant generates 96 MW of electricity – enough to power roughly 40,000 homes for a year, according to the Solid Waste Authority.
Thanks to innovations in waste management, waste-to-energy plants reduce trash in landfills by up to 85 percent, reports the U.S. Energy Information Administration (EIA). How much energy is produced? The organization says:
“In 2016, one ton (2,000 pounds) of municipal solid waste burned in waste-to-energy plants in the United States generated about 474 kilowatt-hours (kWh) of electricity, or about the amount of electricity used by 16 U.S. households in one day.”
Job Outlook in the Waste-to-Energy Sector
There are a number of different types of jobs in the waste-to-energy sector, from research analysts to engineering consultants to waste technicians. Some examples include:
- Maintenance technicians, managers and supervisors
- Electrical and mechanical engineers
- Waste management consultants
- Industrial water and wastewater engineers
- Air quality consultants
- Plant operators, managers and supervisors
- Production and manufacturing engineers
- Industrial waste managers
- Environmental waste consultants
- Greenhouse gas assessors
The industry is becoming more efficient, with advances in technology and materials, along with more mindful consumer behaviors. With less trash making its way into the landfills, more clean energy on the grid, and a positive financial impact, this sector is filled with opportunity for both college grads and seasoned workers looking for more fulfilling careers.
Interested in a clean energy job? Start by creating a free professional profile on Clean Energy Jobs List. Then check out the opportunities near you.