South Korea, a densely populated country that imports 98% of its fuels, is waking up to the value of using landfill gas for electricity and heat generation. A number of projects conducted under the Climate Technology Partnership reveal the promise of this emerging business.
by Christina Larney, Mark Heil, and Gyungae Ha
Historically, municipal solid waste generated in South Korea has been disposed of at open landfill sites. However, during the past 10 years there has been recognition of the issues associated with environmental protection and as a result, poorly located and operated disposal facilities are being closed and replaced by modern regional disposal facilities. Municipal solid waste is increasingly viewed as a potential resource and there is a strong trend toward recycling, composting and combustion technologies.
In 2001 the waste sector in South Korea accounted for 37.6% of the country’s methane emissions with 465 thousand tonnes of CH4 attributed to this sector. Municipal solid waste landfills are a large source of these human-related emissions and represent an opportunity to capture and use a significant energy resource.
With this in mind, utilizing landfill gases from viable landfill sites is an emerging business in the South Korean solid waste treatment market. For example, the city of Seoul installed 100 methane gas extraction wells at the former Nanji landfill site. The captured gas from these wells is sent to the Korea District Heating Corporation (KDHC). KDHC combusts the gas and distributes the heat energy to neighbouring facilities and households for heating and cooling. The Seoul World Cup Stadium is one of the facilities supplied with heat from the LFG project at Nanji.
Landfill gas development
Landfill gas is extracted from landfills using a series of wells and a blower/flare (or vacuum) system. This system directs the collected gas to a central point where it can be processed and treated depending upon the ultimate use for the gas. From this point, the gas can be flared or used to generate electricity, replace fossil fuels in industrial and manufacturing operations, or be upgraded to pipeline-quality gas.
Types of utilization projects
There are several ways to effectively utilize landfill gas for energy. The two primary applications are electricity generation and direct use. The generation of electricity from LFG can be used on-site or sold to the grid. LFG projects can generate electricity through a variety of different technologies, including internal combustion engines, turbines, microturbines, Stirling engines (external combustion engine), Organic Rankine Cycle engines and fuel cells. The vast majority of projects use internal combustion (reciprocating) engines or turbines, with microturbine technology being used at smaller landfills and in niche applications. Certain technologies such as the Stirling and Organic Rankine Cycle engines and fuel cells are still in the development phase.
 South Korea is starting to take advantage of its landfill gas for uses such as power generation |
Employing LFG directly to offset the use of other fuel sources (such as natural gas, coal and oil) is another means by which current projects make use of captured LFG. This direct use of LFG can be in a boiler, dryer, kiln, greenhouse, or other thermal applications. It can also be used to evaporate leachate. Innovative direct uses include firing pottery and glass-blowing kilns; powering and heating greenhouses and ice skating rinks; and heating water for aquaculture. Industries currently using LFG include auto manufacturing, chemical production, food processing, pharmaceutical, cement and brick manufacturing, wastewater treatment, consumer electronics and products, paper and steel production, and prisons and hospitals, among others.
An additional use of LFG is in cogeneration (also known as combined heat and power or CHP) projects that generate both electricity and thermal energy, usually in the form of steam or hot water. Several cogeneration projects have been installed at industrial operations, using both engines and turbines. The efficiency gains of capturing the thermal energy in addition to electricity generation can make these projects very attractive during LFG project consideration.
Production of alternate fuels from LFG is an emerging area. Landfill gas has been successfully delivered to the natural gas pipeline system as both a high-BTU and medium- BTU fuel. LFG has also been converted to vehicle fuel in the form of compressed natural gas (CNG), with a number of liquefied natural gas (LNG) and methanol production projects in the planning stages.
Why pursue LFG projects in South Korea?
Methane recovery can help Korea meet its growing energy needs in a sustainable manner. Korea has a rapidly growing economy and depends extensively on imported fuels that account for 98% of its energy use. There are few reliable energy sources within Korea. Thus, Korea has a compelling need to develop alternate fuel sources to enhance its energy security, economy and environment.
Methane recovery is a suitable source of fuel for Korea considering the country’s high population density, rapid economic development and urbanization. These factors contribute to large concentrations of refuse as well as steady flows of solid wastes into landfill sites which are critical for viable methane recovery projects.
There is also the concern regarding climate change due to methane’s role as a powerful greenhouse gas (GHG). LFG projects in South Korea have the dual effects of both addressing environmental issues and providing a domestic fuel source.
While some LFG projects were already being contemplated and pursued in Korea, the Climate Technology Partnership (CTP - see box on the left) has catalysed its further development by listing landfills suitable for development, providing high-quality feasibility studies, helping reduce regulatory barriers, and informing Korean and international developers of market opportunities.
LFG projects in South Korea - case studies
This article examines two particular sites: Ulsan, on the south-east coast, and a landfill for the city of Cheong-ju, 128 km south-east of Seoul.
Ulsan
The Ulsan site is a municipal landfill with a capacity of 4,255,142 m3. The site was opened in 1994 and is expected to close in 2014. In 1999 Ulsan had 2,297,000 m3 of waste in place that was producing approximately 27 m3 of LFG/minute. The City of Ulsan decided to move forward with the landfill gas project after a feasibility study had been conducted. Construction of the LFG capture and transportation structures started in December 2001, and by August 2002 commercial LFG production had begun.
 Figure 1. Yearly projected LFG output at the Ulsan landfill site |
The Ulsan feasibility study was completed by using actual measurements - not projected solely from a model. Figure 1 shows projected methane production per year over the lifetime of the project and beyond. It indicates that methane production will be at its highest from 1998 to 2018 with a dramatic drop in output closely following the expected closure of the landfill in 2014.
The methane gas recovery system at Ulsan is designed to capture the gas from the landfill and transport it to an adjoining chemical factory, Kumho Chemical Ltd, where it is burned in boilers without being purified.
The Ulsan project was constructed during 2000-2002. The project proceeded with relatively few obstacles and has been operating since 2002. The few obstacles encountered since then were largely due to a lack of experience regarding LFG utilization projects. SK Corporation (SK), the company whose bid to develop the landfill was selected by the city of Ulsan, overcame its inexperience in designing LFG projects by attending USEPA-sponsored trainings in Korea and by visiting the United States to tour landfill sites with LFG projects in place.
Cheong-ju
Cheong-ju is an inland city located 128 km south-east of Seoul. The city occupies an area of 153 km2 and has a population of approximately 595,000 people. It is estimated that 700 tonnes of municipal solid waste is currently generated per day there. This equates to roughly 250,000 metric tonnes per year. Of this total, 50,000 are currently managed by recycling, composting and incineration. The remaining 200,000 tonnes per year are disposed at the site.
Previously, municipal solid waste that was generated in Cheong-ju was disposed at the Moonam Landfill, which served as the main disposal facility for the Cheong-ju province from 1994 to 2000. A new site, the Megalo landfill, opened in 2001 and has replaced Moonam as the primary disposal facility for the Cheong-ju province. The feasibility study for Cheong-ju focuses on the Megalo site. EPA estimates the site could yield GHG reductions in the order of 240,000 tonnes of CO2 equivalent annually by 2010.
The phased approach that was suggested in the Cheong-ju feasibility study can be taken away as a best practice for all LFG projects. In using a phased approach, LFG capture can be monitored to determine the actual rate of landfill gas production. This approach enables project managers to act on incoming data flows, which provides a distinct advantage. By using the phased approach, managers are able to make better decisions about the technical aspects of the project as well as being able to adjust more aptly to changing regulatory frameworks and other processes. In this way, projected landfill gas generation - in terms of various factors including baseline estimates, landfill gas recovery potential, and net annual methane emissions - provided by feasibility studies act as stepping stones to build on and can be verified before incurring greater capital costs. It is common practice in the United States to verify gas generation before proceeding any further on LFG projects.
The overall benefits of the Megalo LFG utilization and gas mitigation project were substantial. They are listed below and often apply to LFG projects in general:
- social and environmental benefits to the community from the utilization of alternative energy and reduced fossil fuel consumption
- use of facility as a tour site to promote awareness and knowledge of greenhouse gas mitigation and renewable energy projects
- consistent with international, national and local objectives for sustainable development
- improved management of municipal solid waste (reduces pollution and overall landfill costs)
- reduction of methane emissions
- potential of displacing fossil fuel use and improving air quality
- domestic source of energy/fuel
- develops local capacity for taking on and completing additional LFG projects
- can be used to develop ‘turnkey’ approach to similar projects
- provides good focal point for dissemination of information.
These benefits, combined with the feasibility study’s finding that ‘the proposed GHG mitigation project is considered to be economically feasible … [with] … a price of US$4.00 per metric tonne of CO2 equivalent,’ make a strong case for the Cheong-ju government to install a LFG recovery and GHG mitigation project at Megalo landfill.
However, despite the various documented benefits and positive findings of the feasibility study, an LFG system has not been constructed at the Megalo landfill in Cheong-ju.
Two of the main obstacles that will need to be overcome in pursuing the project are local officials’ lack of commitment to the project and difficulty in qualifying for certified emission reductions (CERs) under the Clean Development Mechanism (CDM).
 Developing landfill gas projects is a multi-stage process |
The shifting commitments of elected officials can create significant limitations on finding viable projects for development. There can be considerable delays when working with governments due to election cycles and lengthy decision-making processes.
Current status of LFG in Korea
There has been a significant increase in the number of LFG projects across Korea. Market transformation as a result of the Climate Technology Partnership is most noticeable in the methane capture area. When the CTP was started in Korea in 2002, a few landfills were considering the idea of LFG projects. Currently there are at least 17 LFG utilization projects either completed or in the latter stages of development. Four of these projects have direct use applications and 14 use the captured LFG to produce electricity with a total capacity that will be just over 80 MW. There is also one landfill, Hyeul-Dong near Chuncheon city, which is currently planning to convert 80 trucks to run on CNG produced from captured methane at the landfill. Not all of these LFG projects can be linked to CTP Korea, but the CTP mechanism, by forging productive relationships and providing a positive demonstration effect, likely boosted the market. This momentum continues to exert a favourable influence for project development.
Conclusions
In the full paper on which this article is based, the lessons learned from Ulsan and Cheong-ju have been divided into three categories - key factors, best practices and common barriers. The most important factor distinguished here and in the paper is the need for collaboration.
This collaboration can take many forms - such as collaboration between overlapping regulatory authorities and collaboration between private sector partners. Successful projects must navigate carefully through numerous potential pitfalls and bring together many distinct players with varying interests to work collaboratively toward fully developing a project. The importance of careful collaboration cannot be overstated. In its absence, even the most technically and economically feasible projects will not be implemented. Developing a project from an idea to viable, working facility is a multi-stage process. With many agencies involved, it only takes one party to ‘drop the ball’ at a certain stage to inhibit the completion of the project. Whether this is done inadvertently or intentionally, the result is the same.
With widespread energy shortages and the growing prominence of climate change, LFG projects should continue to be pursued actively. LFG projects can provide energy while at the same time mitigating GHG emissions. As LFG projects are viable economically in both developed and developing nations, they provide a strong foundation for these ventures. The challenge is in building effective networks of knowledge and relationships to complete projects successfully despite the various barriers that are often present.
Christina Larney is Policy Analyst at Technology Applications Center, National Renewable Energy Laboratory. Mark Heil is Senior Economist at the Climate Change Division, US Environmental Protection Agency. Gyungae Ha is Project Coordinator at the Center for Climate Change Mitigation Projects, Korea Energy Management Corporation.
e-mail: Heil.Mark@epamail.epa.gov
A more detailed version of this article is posted on the website of the National Renewable Energy Laboratory, and is available at: http://www.nrel.gov/docs/fy07osti/40428.pdf
This work has been co-authored by an employee of the Midwest Research Institute under Contract No. DE-AC36-99GO10337 with the US Department of Energy.
The Climate Technology Partnership
To accelerate the implementation of methane recovery technologies in Korea, the Korean and US governments determined in 2001 that a new programme approach was needed. This is when the Climate Technology Partnership (CTP) was developed with considerable input from the US Agency for International Development (US AID), the US Environmental Protection Agency (US EPA), the Department of Energy (DOE), and the National Renewable Energy Laboratory (NREL). CTP follows on from the Technology Cooperation Agreement Pilot Project (TCAPP).
