As of March 2021, tright here are 550 operational LFG power tasks in the USA and 481 landfills that are good candidates for jobs.

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Landfill gas (LFG) is a organic byproduct of the decomposition of organic product in landfills. LFG is created of about 50 percent methane (the primary component of herbal gas), 50 percent carbon dioxide (CO2) and a small amount of non-methane organic compounds. Methane is a potent greenhome gas 28 to 36 times more reliable than CO2 at trapping warmth in the environment over a 100-year duration, per the latest Intergovernmental Panel on Climate Change (IPCC) assessment report (AR5).

Discover even more around methane egoals in the United States.

Methane Emissions from Landfills

Note: All emission approximates from the Inventory of UNITED STATE Greenhome Gas Emissions and Sinks: 1990–2019.Larger image to save or print

Municipal solid waste (MSW) landfills are the third-largest resource of human-associated methane egoals in the United States, accounting for about 15.1 percent of these egoals in 2019. The methane egoals from MSW landfills in 2019 were approximately indistinguishable to the greenhouse gas (GHG) emissions from more than 21.6 million passenger vehicles moved for one year or the CO2 emissions from practically 12.0 million homes’ energy use for one year. At the same time, methane eobjectives from MSW landfills recurrent a lost opportunity to capture and use a significant energy resource.

When MSW is initially deposited in a landfill, it undergoes an aerobic (via oxygen) decomplace phase once little bit methane is produced. Then, typically within much less than 1 year, anaerobic problems are established and methane-producing bacteria start to decreate the waste and also geneprice methane.

The following diagram illustrates the alters in typical LFG composition after waste placement. Bacteria decreate landfill waste in 4 phases. Gas complace alters via each phase and also waste in a landfill might be undergoing several phases of decomposition at once. The time after placement scale (complete time and also phase duration) varies through landfill conditions.


Figure adapted from ATSDR 2008. Chapter 2: Landfill Gas Basics. In Landfill Gas Primer - An Rundown for Environpsychological Health Professionals. Figure 2-1, pp. 5-6. (PDF)(12 pp, 2MB)

Find Out more in Chapter 1. Landfill Gas Energy Basics of LMOP"s LFG Energy Project Development Handbook.

In October 2009, issued a dominion (40 CFR Part 98) that requires the reporting of (GHG) egoals from large resources and also providers in the USA, and is intended to collect exact and also timely emissions data to increate future plan decisions.

Annually, worries an inventory report to present the U.S. government"s estimates of UNITED STATE human-connected GHG emissions and sinks for annually since 1990. Eobjectives from the waste sector as well as other sectors are presented in this inventory.

Collecting and Treating Landfill Gas

Instead of escaping into the air, LFG can be caught, converted, and also provided as a renewable power resource. Using LFG helps to minimize odors and other perils linked with LFG emissions, and also stays clear of methane from moving right into the environment and also contributing to local smog and also worldwide climate change. In enhancement, LFG energy tasks generate revenue and also produce tasks in the community and beyond. Learn more about the benefits of making use of LFG.


The graphic illustrates the repertoire and processing of LFG to develop methane for multiple offers. First, LFG is built up via vertical and also horizontal piping buried in an MSW landfill. The LFG is then processed and treated for use. The graphic shows potential finish supplies of LFG including industrial/institutional offers, arts and crafts, pipeline gas, and car fuel. 

This graphic mirrors 3 stperiods of LFG therapy. Main Treatment clears moisture as the gas passes via a knockout pot, filter, and breduced. Secondary Treatment requires the use of an after cooler or other added moisture removal (as necessary), adhered to by siloxane/sulfur removal and also compression (as needed). After the impurities are rerelocated in the Secondary Treatment stage, the LFG can be provided to geneprice power or as a medium-Btu fuel for arts and crafts or boilers. State-of-the-art Treatment removes extra impurities (CO2, N2, O2, and also VOCs) and also compresses the LFG right into a high-Btu gas that can be offered for car fuel or injected right into a gas pipeline. Waste/tail gas is sent out to a flare or thermal oxidizer.

Flowchart of a Basic LFG Collection and also Processing System

LFG is extracted from landfills utilizing a collection of wells and also a blower/flare (or vacuum) system. This mechanism directs the built up gas to a main point wright here it deserve to be processed and treated relying on the ultimate usage for the gas. From this suggest, the gas have the right to be flared or beneficially provided in an LFG energy project. Click on the flowchart to watch even more details, consisting of photographs of LFG repertoire and also processing devices.


Landfill Gas Energy Project Types

Tright here are many alternatives obtainable for converting LFG into power. Different types of LFG energy tasks are grouped below right into three broad categories – Electricity Generation, Direct Use of Medium-Btu Gas, and Renewable Natural Gas. Descriptions of job innovations are had under each task type. For even more information on LFG power project innovation choices and the advantages and disbenefits of each, view Chapter 3. Project Technology Options of LMOP’s LFG Energy Project Growth Handbook.

Electricity Generation

About 70 percent of currently operational LFG energy jobs in the United States generate power. A variety of modern technologies, consisting of reciprocating interior burning engines, generators, microgenerators and fuel cells, deserve to be used to generate electricity for onsite usage and/or sale to the grid. The reciprocating engine is the many generally used conversion modern technology for LFG electricity applications because of its fairly low price, high performance and also size varieties that match the gas output of many kind of landfills. Gas wind turbines are commonly offered in larger LFG power jobs while microwind turbines are primarily provided for smaller sized LFG volumes and also in niche applications.

Cogeneration, additionally recognized as merged warmth and also power (CHP), projects use LFG to generate both power and thermal power, usually in the form of vapor or hot water. Several cogeneration tasks utilizing engines or wind turbines have been mounted at industrial, commercial and institutional operations, using engines or wind turbines. The effectiveness gains of catching the thermal energy in enhancement to electricity generation can make this task type extremely attrenergetic.

Direct Use of Medium-Btu Gas

Directly using LFG to counter the use of another fuel (for instance, organic gas, coal or fuel oil) occurs in about 17 percent of the presently operational projects. LFG can be provided directly in a boiler, dryer, kiln, greenhouse or various other thermal application. In these projects, the gas is piped directly to a surrounding customer for usage in combustion tools as a replacement or supplementary fuel. Only limited condensate removal and filtration therapy are compelled, although some changes of existing burning equipment could be vital.

LFG can also be offered straight to evapoprice leachate. Leachate evaporation making use of LFG is a great option for landfills where leachate disposal at a water reresource recovery facility is unobtainable or expensive. LFG is provided to evaporate leachate to a much more concentrated and also even more quickly discarded effluent volume.

Innovative straight supplies of medium-Btu gas encompass firing pottery and glass-blowing kilns; powering and also heating greenhouses; and evaporating waste paint. Current industries utilizing LFG incorporate auto production, chemical manufacturing, food and beverage processing, pharmaceuticals, cement and brick manufacturing, wastewater therapy, consumer electronics and commodities, paper and steel manufacturing, and prisons and also hospitals.

Renewable Natural Gas

LFG can be upgraded to renewable herbal gas (RNG), a high-Btu gas, via therapy processes by enhancing its methane content and also, conversely, reducing its CO2, nitrogen and also oxygen contents. RNG can be offered in place of fossil organic gas, as pipeline-high quality gas, compressed organic gas (CNG) or liquefied natural gas (LNG). About 13 percent of currently operating LFG energy jobs are creating RNG.

Options for usage of RNG include thermal applications, to geneprice electricity or as fuel for vehicles. The RNG can be provided in your area at the website wbelow the gas is developed or deserve to be injected right into herbal gas transmission or distribution pipelines for delivery to another place.

A municipal solid waste (MSW) landfill is a discrete area of land also or excavation that receives household waste, and may additionally get other forms of nonhazardous wastes. Collection of LFG generally starts after a part of a landfill, known as a “cell”, is closed to waste placement.

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LFG collection devices deserve to be configured as vertical wells or horizontal trenches. The the majority of common strategy is drilling vertical wells right into the waste mass and connecting the wellheads to lateral piping that transports the gregarding a repertoire header using a breduced or vacuum induction mechanism. Horizontal trench units are beneficial in areas of active filling. Some landfills usage a combination of vertical wells and also horizontal collectors. Collection system operators “tune” or readjust the wellarea to boost collection.