Energy solutions for a cleaner world
By Kate Brass
North America and around the globe, power producers
and consumers continue to seek new and innovative ways to generate
electricity while preserving the world’s natural resources and
reducing their impact on the environment.
GE Energy, one of the world’s leading suppliers of
power generation technology and services, is committed to the
development of alternative and renewable energy solutions. Numerous
GE Energy products are certified under ecomagination, a
corporate-wide initiative to aggressively bring to market new
technologies that will help customers meet pressing environmental
challenges.
Two examples within the GE portfolio are integrated
gasification combined-cycle (IGCC) or "cleaner coal" technology; and
the use of biogas (including methane created through the digestion
of agricultural or animal waste) as a fuel to generate electricity
to support a farm’s onsite power/heat requirements and potentially
the local transmission grid.
GE’s Jenbacher Gas Engines
GE Energy’s Jenbacher business, based in Austria, is
a leading provider of advanced gas engine technology that is durable
and flexible enough to handle the fluctuating quality of a variety
of specialty gases, including biogas generated from the anaerobic
digestion of animal waste (cow manure, for example)—an application
that is beginning to take hold in both Canada and the United States
after being widely practiced in Europe for decades.
Biogas is an attractive alternative to conventional
fuels in areas where the waste fuel source and the energy demand are
co-located. Using biogas for power generation allows for economic,
highly efficient combined generation of power and heat. The residual
products from the biomass fermentation process provide additional
benefits to the process as it can serve as valuable fertilizer that
can be used by the operator or sold to create a revenue stream.
Biogas digester projects provide a way to capture
and reduce the ventilation of methane, a potent greenhouse gas,
which aids U.S. and Canadian efforts to reduce their respective
industrial greenhouse gas emissions levels.
The benefits of biogas power generation are being
realized today on a 36,000-head feedlot in Vegreville, in the
Canadian province of Alberta. As part of a pilot-scale project,
Highmark Renewables has installed a one-megawatt (MW) GE Energy-Jenbacher
cogeneration system to utilize the biogas created during the
anaerobic digestion of cow manure.
The application is also becoming increasingly
popular in dairy regions of the United States, including the
Norswiss Farm in Wisconsin, where GE Energy supplied a Jenbacher JMS
316 generator set that was installed by the Dairyland Power
Cooperative as part of a cow manure digester-biogas project. The
Jenbacher unit was commissioned in March 2006, and generates 848
kilowatts (kW) of electricity. Thermal power from the system is used
to heat water to support the manure digestion process.
The demand for GE’s Jenbacher biogas engines for
such methane-digester projects has been steadily growing in North
America, driven by new regulations and incentives adopted in both
countries to promote the development of new renewable energy
sources.
A Cleaner Choice for an Abundant Fuel
Historically, the use of coal—one of the world’s
most abundant fuels—has been associated with concerns about
increased air pollution. IGCC power systems provide a cost effective
way to reduce the emissions levels associated with power generation
from pulverized coal.
Gasification technology has been available and
proven for many years but has experienced a number of barriers to
widespread commercialization, including cost and the perceived
performance challenges relative to other technologies such as
pulverized coal and gas turbine combined cycle.
GE has resolved these challenges by creating an IGCC
product offering that integrates gasification and power generation
technologies. GE created a single-point IGCC solution for customers,
by forming an alliance with Bechtel Power, to develop a standardized
commercial offering for projects in North America. This turnkey
reference plant has been designed for optimized plant performance
and reliability, while also providing the commercial cost, schedule
and performance guarantees required for a customer to confidently
move forward with a project.
Three of the key focus areas for the reference plant
design are environmental performance, capital cost and cost of
electricity. One of the critical drivers for IGCC is its strong
environmental performance; emissions targets set for the reference
plant design approach the emissions achieved by natural gas
combined cycle plants.
Historically, an IGCC plant would cost 20-25 percent
more than a comparable supercritical pulverized coal (SCPC) plant.
The GE and Bechtel alliance’s reference plant is targeted at cutting
the capital cost premium for IGCC in half for a state-of-the-art,
greenfield pulverized coal plant of the same size. This reduction
will be realized as the volume of plants in operation increases over
time. Early cost premiums can be offset by incentive programs such
as the Federal Investment Tax Credits (ITC) and state and local
incentive programs.
Another measure of critical importance to power
generators when evaluating their new generation alternatives is the
cost of electricity. Environmental benefits of IGCC will reduce the
cost of electricity from avoided emissions credit costs. IGCC’s
emissions are 33 percent to 90 percent lower than a comparable SCPC
plant equipped with state-of-the-art emissions control equipment.
When combined with an IGCC plant’s lower water usage, reduced waste
disposal costs and potential to use lower cost fuels, electricity
cost is further reduced.
Another factor that must be considered is the
likelihood of a coal project being permitted. Coal plants have come
under greater scrutiny and public resistance. Several coal projects
have recently been cancelled. Failed projects ultimately drive
utilities to higher cost sources of electricity or failure to meet
demand. Because of its superior environmental performance, IGCC is
more likely to receive public and government support towards
successful permitting.
With carbon constraint regulations approaching on
the regulatory horizon, coal plants are likely to be required to
capture and sequester CO2 (or purchase carbon credits). In this
context, IGCC becomes a better solution both economically and
environmentally than other coal-to-power solutions. The IGCC cost of
electricity with 90 percent CO2 capture is projected to be 10
percent lower than that of an SCPC plant. IGCC has the advantage of
being carbon-capture ready today and has the proven technology
necessary to capture CO2 at commercial scale. Currently 25 GE
gasification plants are capturing CO2 at levels up to 90 percent and
22 GE gas turbines are operating on hydrogen-rich fuel gas (up to 90
percent H2).
At GE, we’re taking a new approach to solving some
of our customer’s toughest environmental problems as part of our
ecomagination program. IGCC and Jenbacher Gas Engines are just two
of the many products and services that we’re bringing to market as
part of our commitment to developing new, cleaner energy
technologies. We are focused on continuing to find ways to develop
new technologies that will use low-grade, waste and renewable fuels
to meet the energy demands of a growing world. To us, it’s about
smart, resourceful—and sometimes unexpected—solutions to our
customers’ everyday challenges and helping address some of the
world’s most pressing environmental dilemmas, today and for
generations to come.
Further information is available at
www.gepower.com/ecomagination .
Return