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Low carbon power comes from sources that produce fewer greenhouse gases than do traditional means of power generation. It includes zero carbon power generation sources, such as wind power and solar power, as well as sources with lower-level emissions such as natural gas, and technologies that prevent carbon dioxide from being emitted into the atmosphere, such as carbon capture and storage. These power-generation techniques emit significantly less carbon dioxide than a traditional fossil fuel power plant.

Low carbon power stems from the idea that to reduce carbon emissions, no single technology or solution can handle the problem alone, but the sum of all the possibilities across the transportation, industry, power, agriculture & waste, forestry and buildings sectors, makes the necessary change viable. Low carbon power goes a step beyond renewable energy to include such methods as carbon capture, nuclear energy and natural gas. It is not limited to zero-emissions technologies, but to those that over time drastically reduce the amount of current emissions from each sector.

History

Over the past 30 years, significant findings regarding global warming highlighted the need to curb carbon emissions. From this, the idea for low carbon power was born. The Intergovernmental Panel on Climate Change (IPCC), established by the World Meteorological Organization (WMO) and the United Nations Environment Program (UNEP) in 1988, set the scientific precedence for the introduction of low carbon power. The IPCC has continued to provide scientific, technical and socio-economic advice to the world community, through its periodic assessment reports and special reports.

Internationally, the most prominent early step in the direction of low carbon power was the signing of the Kyoto Protocol, which came into force on February 16, 2005, under which most industrialized countries committed to reduce their carbon emissions. The historical event set the political precedence for introduction of low carbon power technology.

On a social level, perhaps the biggest factor contributing to the general public’s awareness of climate change and the need for new technologies, including low carbon power, came from the documentary An Inconvenient Truth, which clarified and highlighted the problem of global warming.

What is low carbon power?

Differentiating attributes

There are many options for lowering current levels of carbon emissions. Some options, such as wind power and solar power, produce no carbon emissions, using entirely renewable sources. Other options, such as nuclear power, produce no carbon emissions, but come from non-renewable sources (uranium). The term low carbon power can also include power that continues to utilize the world’s natural resources, such as natural gas and coal, but employs techniques that reduce carbon emissions from these sources when burning them for fuel.

As the single largest emitter of carbon dioxide in the United States, the electric-power industry accounted for 39% of CO₂ emissions in 2004, a 27% increase since 1990. Because the cost of reducing emissions in the electricity sector appears to be lower than in other sectors such as transportation, the electricity sector may deliver the largest proportional carbon reductions under an economically efficient climate policy.

Technologies to produce electric power with low-carbon emissions are already in use at various scales. Together, they account for roughly 28% of all U.S. electric-power production, with nuclear power representing the majority (20%), followed by hydroelectric power (7%). However, demand for power is increasing, driven by increased population and per capita demand, and low carbon power can supplement the supply needed.

Examples of low carbon technology

Carbon capture and storage

By capturing emissions and burying them in non-atmospheric reservoirs, coal-fired plants can reduce their greenhouse gas emissions by up to 90 percent. The process of stripping out carbon dioxide leaves hydrogen to power modified generators and can even be used to flush additional oil and gas reserves from dormant oil fields.

In countries with some of the highest levels of emissions, carbon capture stands to benefit economies the most. Another economic implication is that the higher the price of oil, the more valuable the captured CO₂. Captured CO₂ can often be sold to an oil company that injects it into oil fields to squeeze out more oil.

In California, a hydrogen-fueled power plant is in the works that is designed to generate 500MW of electricity and reduce greenhouse gas emissions for some 325,000 homes and businesses in southern California. The proposed project would combine a number of existing industrial processes to provide a new option for generating electricity without significant CO₂ emissions. They would first convert petroleum coke produced at California refineries to hydrogen and CO₂ gases with around 90% of the CO₂ captured and separated. The hydrogen gas stream would then fuel a gas turbine to generate electricity. The captured CO₂ would be transported via pipeline to an oilfield and injected into reservoir rock formations thousands of feet underground, both stimulating additional oil production and permanently trapping the CO₂.

Natural gas and combined cycle gas turbines

While it may seem counterintuitive that natural gas is a source of low carbon power, of all the fossil fuels used in power generation, it emits the least carbon dioxide.

Through the combined cycle process, a gas turbine generator generates electricity and the waste heat from the gas turbine is used to make steam to generate additional electricity via a steam turbine; this last step enhances the efficiency of electricity generation.

Hydroelectric power

Hydroelectric power currently supplies about 19% of world electricity and can be very cost-effective at a large scale. However, most of the sites suitable for large-scale hydroelectric plants in developed countries are either already in use or are unsuitable due to environmental concerns.

Although hydroelectric power generators produce no carbon dioxide emissions, there can be significant emissions of carbon dioxide and methane from the decay of the flooded plant life behind the dam. Small-scale hydropower operations do not create this kind of environmental impact but are much more expensive.

Wind power

Wind power supplies roughly the same amount of electricity as geothermal, and new wind facilities are being built at a rapid pace. Since the fuel cost for wind is zero, the total cost per kilowatt-hour is roughly competitive with other low-carbon sources, such as new nuclear power plants.

The claim is sometimes made that manufacturing wind turbines and building wind plants creates large emissions of carbon dioxide. This is false. Several studies have found that even when these operations are included, wind energy’s CO₂ emissions are quite small—on the order of 1% of coal or 2% of natural gas per unit of electricity generated. Or in other words, using wind instead of coal reduces CO₂ emissions by 99%, using wind instead of gas by 98%.

Solar power

The amount of solar energy that reaches the United States each year is equivalent to approximately 4,000 times the nation’s total electric power needs, but tapping that energy is relatively expensive. Costs for solar photovoltaic (PV) cells are five to 10 times higher than those of other low-carbon technologies, and the average power produced at even the best sites is less than a quarter of the energy produced at noon on a sunny day. Significant research efforts are underway in basic science to improve the performance of PV cells, which may lead to cost reductions in the near future.

Nuclear power

Nuclear power is the largest deployed technology among current low-carbon energy sources, but the capital cost of building a nuclear station is considerably larger than that of a coal-fired plant with conventional pollution control. If nuclear power is to keep its present 20% share of electricity production—from 103 plants now operating—30 new nuclear plants must be brought into service by 2020 to keep up with increasing demand. After 2020, many existing nuclear plants may have to close because of age, and construction will have to reach very high levels if market share is to be maintained.

Geothermal power

Geothermal electricity generation technology uses naturally occurring hot water, such as geysers and hot springs, to generate power, and has been in use since 1904. As of November 2007, it is limited to places with hydrothermal resources and only uses a small percentage of the heat trapped in the earth. Future technologies may be able to access the heat held in rocks close to molten magma deep beneath the Earth’s surface.

Tidal power

Harnessing the tides in a bay or estuary has been achieved in France (since 1966), Canada and Russia, and could be achieved in other areas with a large tidal range. The trapped water turns turbines as it is released through the tidal barrage in either direction. One possible fault is that the system would generate electricity most efficiently in bursts every six hours (once every tide). This limits the applications of tidal energy.

The outlook for low carbon power

Emissions

The Intergovernmental Panel on Climate Change stated in its first working group report that “most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations, contribute to climate change.

As a percentage of all anthropogenic greenhouse gas emissions, carbon dioxide (CO₂) accounts for 72 percent, and has increased in concentration in the atmosphere from 315 parts per million (ppm) in 1958 to more than 375 ppm in 2005.

Emissions from energy make up more than 61.4 percent of all greenhouse gas emissions. Power generation from traditional coal fuel sources accounts for 18.8 percent of all world greenhouse gas emissions, nearly double that emitted by road transportation.

Estimates state that by 2020 the world will be producing around twice as much carbon emissions as it was in 2000.

Electricity usage

World energy consumption is predicted to increase from 421 quadrillion British Thermal Units (BTU) in 2003 to 722 quadrillion BTU in 2030. Coal consumption is predicted to nearly double in that same time. The fastest growth is seen in non-OECD Asian countries, especially China and India, where economic growth drives increased energy use. By implementing low carbon power options, world electricity demand could continue to grow while maintaining stable carbon emission levels.

Energy infrastructure

By 2015, one-third of the 2007 U.S. coal plants will be more than 50 years old. Nearly two-thirds of the generation capacity required to meet power demand in 2030 is yet to be built. There are currently 151 new coal-fired power plants planned for the U.S., providing 90GW of power.

Viability

Improvements to current carbon capture technologies could reduce CO₂ capture costs by at least 20-30% over approximately the next decade, while new technologies under development promise more substantial cost reduction.

Investment

Investment in low carbon power sources and technologies is increasing at a rapid rate. Zero-carbon power sources produce about 2% of the world's energy, but account for about 18% of world investment in power generation, attracting $100 billion of investment capital in 2006.

Advocates and practitioners

• Achim Steiner
• Al Gore
• Andrew C. Revkin
• Arnold Schwarzenegger
• Bill Clinton
• Dr. Rajendra K. Pachauri
• Fred Krupp
• Jack Manning
• Jim Rogers
• Lee Scott
• Leonardo DiCaprio
• Lord John Browne
• Mark B. Goldfus
• Mark Tercek
• Michael Bloomberg
• Richard Sandor
• Simran Sethi
• Susan Solomon
• Theodore Roosevelt IV
• Timothy E. Wirth
• Vinod Khosla

Organizations

• American Wind Energy Association
• BP Solar
• Carbon Capture and Sequestration Technologies Program at MIT
• Carbon Sequestration Leadership Forum
• Clipper Windpower
• Committee on Regional Electric Power Coordination
• Edison Mission Group
• Energy Information Administration
• European Wind Energy Association
• GE Ecoimagination
• Horizon Wind Energy
• International Energy Agency
• Intergovernmental Panel on Climate Change
• National Energy Technology Laboratory
• National Wind Coordinating Collaborative
• National Oceanic & Atmospheric Administration
• North American Carbon Program
• Pew Center on Global Climate Change
• Rio Tinto
• Tata Power
• The California Institute of Technology
• US Department of the Interior’s Bureau of Land Management
• US Department of Energy
• US Nuclear Regulatory Commission
• US Climate Action Partnership
• US National Academy of Sciences
• World Energy Outlook
• World Wind Energy Association

See also

• Coal with carbon capture
• Wind power
• Solar power
• Natural gas
• Nuclear power
• Energy portal
• Carbon sink
• Carbon capture and storage
• Global warming
• Climate Change
• IPCC
• Greenhouse gases
• Renewable energy
• Energy development

References

1. Vattenfall website; “Climate Map 2030”
2. Intergovernmental Panel on Climate Change Web site
3. Low-carbon economy Misplaced Pages Entry on “Carbon Economy”
4. The Christian Science Monitor; “New case for regulating CO2 emissions”
5. ^ Issues in Science & Technology Online; “Promoting Low-Carbon Electricity Production”
6. The Pew Center on Global Climate Change; “Global Warming in Depth”
7. Popular Mechanics; “The Truth About Hydrogen”
8. Scientific American, “A Plan to Keep Carbon in Check”
9. Resource Investor, “Coal to Alternatives, Carbon Capture Get a Big Boost”
10. Instrumentation, Systems, and Automation Society online, “Hydrogen power plant on tap for California”
11. Union of Concerned Scientists online; "How natural gas works"
12. Misplaced Pages Entry on “Combined Cycle” (CCGT)
13. American Wind Energy Association online; “The Most Frequently Asked Questions About Wind Energy”
14. Tidal power
15. Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Intergovernmental Panel on Climate Change (2007-02-05). Retrieved on 2007-02-02.
16. Greenhouse gas
17. Carbon Dioxide Information Analysis Center (CDIAC), the primary climate-change data and information analysis center of the U.S. Department of Energy (DOE)
18. ^ World Resources Institute; “Greenhouse Gases and Where They Come From”
19. Energy Information Administration; “World Carbon Emissions by Region”
20. Energy Information Administration; “International Energy Outlook 2006”
21. Time for Change,org; “Prediction of Energy Consumption World-Wide”
22. Energy Information Administration; “World Market Energy Consumption by Region”
23. ^ National Resources Defense Council Web site; "Hearing on Future Options for Generation of Electricity from Coal"
24. ^ The National Energy Technology Laboratory Web site “Tracking New Coal Fired Power Plants”
25. United Nations Environment Program Global Trends in Sustainable Energy Investment 2007

• Alternative energy
• Energy development
• Low-carbon economy