https://www.americancityandcounty.com/wp-content/themes/acc_child/assets/images/logo/footer-logo.png
  • Home
  • Co-op Solutions
  • Hybrid Work
  • Commentaries
  • News
  • In-Depth
  • Multimedia
    • Back
    • Podcast
  • Resources & Events
    • Back
    • Resources
    • Webinars
    • White Papers
    • IWCE 2022
    • How to Contribute
    • Municipal Cost Index – Archive
    • Equipment Watch Page
    • American City & County Awards
  • About Us
    • Back
    • About Us
    • Contact Us
    • Advertise
    • Privacy Statement
    • Terms of Service
American City and County
  • NEWSLETTER
  • Home
  • Co-op Solutions
  • Hybrid Work
  • Commentaries
  • News
  • In-Depth
  • Multimedia
    • Back
    • Podcasts
  • Resources/Events
    • Back
    • Webinars
    • White Papers/eBooks
    • IWCE 2022
    • How to Contribute
    • American City & County Awards
    • Municipal Cost Index
    • Equipment Watch Page
  • About Us
    • Back
    • About Us
    • Contact Us
    • Advertise
    • Cookie Policy
    • Privacy Stament
    • Terms of Service
  • newsletter
  • Administration
  • Economy & Finance
  • Procurement
  • Public Safety
  • Public Works & Utilities
  • Smart Cities & Technology
  • Magazine
acc.com


City powers plant with landfill methane

City powers plant with landfill methane

In 1995, the city of Greensboro, N.C., faced a major challenge: disposing of the methane gas that had escaped into the atmosphere from refuse buried in
  • Written by American City & County Administrator
  • 1st December 1997

In 1995, the city of Greensboro, N.C., faced a major challenge: disposing of the methane gas that had escaped into the atmosphere from refuse buried in the city’s landfill.

Clean Air Act regulations mandated the disposal because of concerns about carbon dioxide and methane emissions that occur when landfill waste is digested by bacteria. As the gas builds in the landfill, pressure forces it up into the atmosphere. Once airborne, the gas is diluted and does not pose an explosive threat but has been identified as a potential contributor to the greenhouse effect.

A partnership between the city, Duke Engineering & Services, a Charlotte, N.C.-based company and subsidiary of Duke Energy Company; and Cone Mills Corporation, a local textile company, has resulted in an innovative and self-sustaining landfill gas recovery project that protects the environment, generates revenue for the municipality and supplies an economical source of supplemental energy to a large textile manufacturer.

By partnering with an engineering company and an industrial user, the city eliminated the need for capital outlay and taxpayer funding. This public-private partnership has saved local public dollars that would have been needed to meet regulatory landfill gas management requirements.

During the life of the landfill, the city (like nearly all landfill owners) had passively vented gas, a slow process that enabled the gas to migrate away from the landfill site. By the time the Clean Air Act was passed, the city’s landfill had buried more than 7 million tons of solid waste, far surpassing the 2 million-ton limit set forth by legislation.

Greensboro did not want to simply collect the gas and burn it off into the atmosphere where it could harm the ozone. Instead, the city wanted a more innovative and less wasteful solution.

With passage of the Clean Air Act, private companies interested in receiving tax credits for generating renewable energy contacted Greensboro.

The companies’ proposals, however, usually involved large capital outlays and provided only the environmental benefit of compliance with the act.

Unsatisfied with that option, Greensboro considered building a generating site to supply electricity to the city-owned Osborne Water Treatment Plant.

Greensboro contacted an engineering company to discuss the possibility of working together to construct and operate such a generating facility. Engineers analyzed the idea, gathered data and determined the amount of gas the landfill would generate each year.

Knowing the quantity of gas expected in the future, the engineers examined several technologies, including purifying the gas and producing electricity through a gas turbine. Neither option was considered economically feasible, yet preliminary studies showed that the gas was, in fact, a viable fuel.

While visiting other gas collection systems, city officials observed a system that transported landfill gas through a pipeline to a pharmaceutical corporation which used the gas for supplemental steam energy.

Knowing that one of the city’s major manufacturers, Cone Mills, had a nearby plant with a gas-fired broiler, city officials discussed the possibilities with their engineering firm, which, coincidentally, was conducting a boiler realignment at the plant.

If the landfill could pipe the gas without further treatment to the boiler, the capital investment could be kept low enough to make the project economical.

In order to collect the gas from the landfill, engineers drilled wells into the buried waste. A perforated length of pipe was centered in the hole, and gravel was added to hold it in place and to provide a porous space between the rocks where gas would collect.

A gas main was constructed from the landfill to a gas blower, which pulled a vacuum on the wells and compressed the gas to about 10 pounds-per-square inch.

As the gas was compressed in the blower, its temperature rose above 200 degrees, but, to keep it from damaging the plastic pipeline, it had to be cooled to below 150 degrees.

However, any cooling of the gas brought it below its dew point and caused water droplets to form. Therefore a knockout drum was required just before the blower to keep droplets of water from damaging the fast-moving impeller in the blower.

Under the current arrangement, gas is sold to the textile plant on the basis of its BTU content. A metering station was placed at the plant where the boiler is located to measure gas flow.

Another flow rate meter was placed at the landfill, where an employee of Natural Power, a Raleigh, N.C.-based subcontractor of Duke Engineering, works full-time monitoring the gas collection system. Although the gas is not being flared into the atmosphere, flares were installed to remove the gas if the boiler were to shut down or in the event of an emergency.

By mid-1997, 54 wells had been drilled, each designed for its specific location within the landfill. Within the next year, the company plans to drill and install 39 more wells as active sections of the landfill are closed.

The system currently generates approximately 2 million cubic feet of gas per day, which easily meets the supplemental power requirements of the plants’ boilers.

The project cost approximately $5 million, but the city paid only for the initial feasibility study. DE&S agreed to pay royalties on the gas it pumped from the landfill, and, when the city’s contract with the engineering company expires in 2007, the city will become the owner of the system. At that time, the city will have several options, including contracting out the operation of the system or operating it as part of the city government.

Who helped: Duke Engineering and Services, Cone Mills, Natural Power, Chevron Plexco, Hoffman, LFG Specialties

Tags:

Most Recent


  • Report: Local and state governments are facing a retention crisis; the worst could be yet to come
    When the pandemic struck in 2020, public retention was hit hard: jobs in local government plummeted by 8.5 percent; state employment dropped by 4.4 percent. Two years later, local and state government jobs have rebounded by about half—to 4.1 and 1.9 percent below pre-pandemic levels respectively, according to a new report from Mission Square Research […]
  • Amid an unprecedented increase in federal spending, cities and counties stand to benefit from partnerships
    The so-called “American dream” of upward mobility has more or less stagnated: Today, a little more than 40 percent of children raised at the bottom of the income ladder remain there as adults, according to Pew Charitable Trusts, and only half grow up to earn more than their parents. This data points to a concerning […]
  • hybrid technology
    Governments using technology to harness data and improve decision-making
    There’s one kind of technology that state and local governments covet, says Rob Carey, president of Cloudera Government Solutions. “While supporting multiple state and local government agencies, our team has noticed an increase in the need for hybrid cloud solutions.” A hybrid cloud is the combination of both public and private cloud deployment models. In […]
  • Seattle-Tacoma-Bellevue, WA
    Infrastructure highlighted by city leaders as top priority in analysis of 60 mayoral addresses
    After two years of ping-pong lockdown orders, mask mandates, unprecedented vaccine drives and economic uncertainty, cities across the United States are beginning to emerge in the pandemic’s aftermath, and they’re prioritizing infrastructure, according to a report published Wednesday by the National League of Cities (NLC).  “The new normal, as we now understand it, is here,” […]

Leave a comment Cancel reply

-or-

Log in with your American City and County account

Alternatively, post a comment by completing the form below:

Your email address will not be published. Required fields are marked *

Related Content

  • North Texas alliance partners with Marketplace.city on smart government solutions
  • Harris County deploys next-generation security in 150 public buildings
  • Public procurement can be transformative for stakeholders in a community
  • The 10 Most Sustainable Large U.S. Cities

White papers


How to Assemble a Rockstar Website Redesign Steering Committee

7th June 2022

Hand Hygiene: Compliance Matters

23rd May 2022

What it Takes to Build a Winning Esports Program

23rd May 2022
view all

Events


PODCAST


Young Leaders Episode 4 – Cyril Jefferson – City Councilman, High Point, North Carolina

13th October 2020

Young Leaders Episode 3 – Shannon Hardin – City Council President, Columbus, Ohio

27th July 2020

Young Leaders Episode 2 – Christian Williams – Development Services Planner, Goodyear, Ariz.

1st July 2020
view all

Twitter


AmerCityCounty

Report: Local and state governments are facing a retention crisis; the worst could be yet to come dlvr.it/SSnmS7

24th June 2022
AmerCityCounty

Amid an unprecedented increase in federal spending, cities and counties stand to benefit from partnerships dlvr.it/SSkGBn

23rd June 2022
AmerCityCounty

Governments using technology to harness data and improve decision-making dlvr.it/SSk3H0

23rd June 2022
AmerCityCounty

Infrastructure highlighted by city leaders as top priority in analysis of 60 mayoral addresses dlvr.it/SSgBck

22nd June 2022
AmerCityCounty

Oklahoma City puts the focus on employees when implementing changes in office technology dlvr.it/SSfyns

22nd June 2022
AmerCityCounty

We want to hear from you! Please take this brief survey and let us know how your organization is managing your budg… twitter.com/i/web/status/1…

22nd June 2022
AmerCityCounty

Buying smart solutions: Technology is now part of (almost) every government purchase dlvr.it/SSbj3Z

21st June 2022
AmerCityCounty

Amid tech labor shortage, outsourcing digital services could provide relief dlvr.it/SSbj23

21st June 2022

Newsletters

Sign up for American City & County’s newsletters to receive regular news and information updates about local governments.

Resale Insights Dashboard

The Resale Insights Dashboard provides model-level data for the entire used equipment market to help you save time and money.

Municipal Cost Index

Updated monthly since 1978, our exclusive Municipal Cost Index shows the effects of inflation on the cost of providing municipal services

Media Kit and Advertising

Want to reach our digital audience? Learn more here.

DISCOVER MORE FROM INFORMA TECH

  • IWCE’s Urgent Communications
  • IWCE Expo

WORKING WITH US

  • About Us
  • Contact Us

FOLLOW American City and County ON SOCIAL

  • Privacy
  • CCPA: “Do Not Sell My Data”
  • Cookies Policy
  • Terms
Copyright © 2022 Informa PLC. Informa PLC is registered in England and Wales with company number 8860726 whose registered and Head office is 5 Howick Place, London, SW1P 1WG.
This website uses cookies, including third party ones, to allow for analysis of how people use our website in order to improve your experience and our services. By continuing to use our website, you agree to the use of such cookies. Click here for more information on our Cookie Policy and Privacy Policy.
X