Renewable Energy Technology Assessments - Kauai Island Utility ...

Kaua’i Island Utility Cooperative
Renewable Energy Technology Assessments
3.0 Renewable Energy Technology
Options
Such sites are attractive to LFG developers because the resource is generally well known
and accessible.
In some cases, the payback period of LFG energy facilities is between 2 and 5
years, especially when environmental credits are available and the gas collection system
is already in place. Capital costs are dependent on the conversion technology and landfill
characteristics, especially the presence of a gas collection system. The cost of installing a
gas collection system at an existing landfill can be prohibitive. Performance and cost
estimates for typical LFG projects using reciprocating engines are summarized in Table
3-7.
Table 3-7. Landfill Gas Technology Characteristics.
Performance
Typical Duty Cycle Baseload
Net Plant Capacity, MW 0.2-15
Capacity Factor, percent 70-90
Economics
Capital Cost, $/kW 1,700-3,500
Variable O&M, $/MWh 20
Levelized Cost, $/MWh 44-63
Technology Status
Commercial Status Commercial
Installed US Capacity, MW 1,100
Kauai Potential Good, but limited resource
Environmental Impacts
Combustion of landfill gas, as with nearly any other fuel source, does release
some environmental pollutants. However, landfill gas to energy systems are generally
viewed in a positive light by environmentalists because landfill gas that is otherwise
released to the atmosphere is a significant source of greenhouse gas emissions. As a
greenhouse gas, methane is 23 times more powerful than carbon dioxide. Collecting the
gas and converting the methane to carbon dioxide through combustion greatly reduces the
potency of LFG as a source of greenhouse gas emissions.
Kauai Outlook
There is good, but limited potential for LFG on Kauai. Trash generated on Kauai
is taken to one central landfill, near Kekaha on the west side of the island. This landfill
21 March 2005 3-20 Black & Veatch