Characterization of uncertainty in estimation of methane collection from select U.S. landfills

Xiaoming Wang, Ajay S. Nagpure, Joseph F. Decarolis, Morton A. Barlaz

Research output: Contribution to journalArticlepeer-review

16 Scopus citations

Abstract

Methane is a potent greenhouse gas generated from the anaerobic decomposition of waste in landfills. If captured, methane can be beneficially used to generate electricity. To inventory emissions and assist the landfill industry with energy recovery projects, the U.S. EPA developed the Landfill Gas Emissions Model (LandGEM) that includes two key parameters: the first-order decay rate (k) and methane production potential (L0). By using data from 11 U.S. landfills, Monte Carlo simulations were performed to quantify the effect of uncertainty in gas collection efficiency and municipal solid waste fraction on optimal k values and collectable methane. A dual-phase model and associated parameters were also developed to evaluate its performance relative to a single-phase model (SPM) similar to LandGEM. The SPM is shown to give lower error in estimating methane collection, with site-specific best-fit k values. Most of the optimal k values are notably greater than the U.S. EPA's default of 0.04 yr-1, which implies that the gas generation decreases more rapidly than predicted at the current default. We translated the uncertainty in collectable methane into uncertainty in engine requirements and potential economic losses to demonstrate the practical significance to landfill operators. The results indicate that landfill operators could overpay for engine capacity by $30,000-780,000 based on overestimates of collectable methane.

Original languageEnglish (US)
Pages (from-to)1545-1551
Number of pages7
JournalEnvironmental Science and Technology
Volume49
Issue number3
DOIs
StatePublished - Feb 3 2015

Fingerprint

Dive into the research topics of 'Characterization of uncertainty in estimation of methane collection from select U.S. landfills'. Together they form a unique fingerprint.

Cite this