What is Global Warming?
There is widespread agreement among climate scientists worldwide that human activity is increasing the greenhouse gases in the earth's atmosphere and accelerating global warming. (Reference: Intergovernmental Panel on Climate Change.)
Heat trapping or "greenhouse gases" in the Earth's atmosphere -- primarily water vapor (H2O), carbon dioxide (CO2), and methane (CH4) -- serve as a "blanket" for keeping the Earth's climate habitable. With industrialization and population growth, greenhouse gas emissions from human activities (like the burning of coal and oil) have significantly increased.
As CO2 and other greenhouse gases increase in the atmosphere, so do their insulating effect, and so the Earth is getting warmer.
According to the National Academy of Sciences, the Earth's surface temperature has risen by about 1 degree Fahrenheit in the past century, with accelerated warming during the past two decades.
This may not seem like much but scientists now predict a global temperature rise between 2.5oF and 10.5oF during this century - a faster temperature rise than humans have ever known.
How does Global Warming affect the Pacific Northwest?
Climate scientists generally agree that if we continue releasing CO2 into the atmosphere, global temperatures will continue to rise and our climate will change. But this does not mean a gradual increase in temperature. Climate models predict an increase in violent weather - severe storms, floods, and drought - with potentially devastating impacts on plant and animal populations, and adverse effects on human health.
Shrinking glaciers on Mt. Rainier are one sign of global warming.
The University of Washington's Climate Impacts Group has reported on possible impacts to the Northwest region. The most likely scenario would be disruption to normal hydrological cycles resulting in less snowpack and more flooding - affecting hydropower generation, salmon survival and water resources in general.
As an example of changes that have already occurred, Mt. Rainier's glaciers shrank 21% in area and 25% in volume during the period 1913 - 1994. Of the 150 glaciers once found in Glacier National Park only 35 remain. These could be gone within 30 years.
What is Seattle City Light doing?
Seattle City Light is taking actions now to work with customers to improve energy efficiency, encourage sustainable development, and expand supplies of new renewable energy resources - actions that help reduce demand for fossil fuels that contribute to global warming.
1977 - Seattle City Light has operated energy conservation programs since 1977, saving enough electricity to power the homes of two cities the size of Seattle. An added benefit of energy conservation is its role in reducing greenhouse gas emissions. Avoided energy production in 2003 reduced the release of carbon dioxide into the atmosphere by about 326,000 tons.
1992 - The Seattle City Council identified responding to climate change as a City of Seattle environmental priority.
1995 - Seattle City Light joined the Climate Challenge, a U.S. Department of Energy voluntary program, through which we report projects that reduce or sequester greenhouse gas emissions, such as conservation, efficient electricity production and tree planting.
2000 - The City of Seattle's Earth Day Resolution was passed. It directed Seattle City Light to begin meeting load growth with cost-effective conservation and renewables, and to mitigate for green house gas emissions from any fossil fuel use. It also set a long-term goal of "Net Zero" greenhouse gas emissions, which Seattle City Light plans to achieve in 2005.
2001 - July 2001, the Greenhouse Gas Mitigation Strategy Resolution was passed, setting standards for calculating greenhouse gas emissions and mitigation projects. Greenhouse gas emissions come from Seattle City Light operations, the operation of vehicles, natural gas used to heat facilities, etc.
2002 - City Light began receiving energy from the Stateline Wind Project in January 2002. As a result of this contract, we now have 175 megawatts of wind generating capacity which will produce an average of 54 megawatts per year. The contract runs until 2021.
2003 - First greenhouse gas offset contract signed with Climate Trust through which Seattle City Light buys offsets from cement material substitution. ( see City of Seattle Ordinance #121062 )
2004 - Biodiesel program implemented. City Light funds the use of biodiesel in several local vehicle fleets - trucks, buses, garbage hauling equipment, and even ferries. Gallon for gallon, biodiesel production and combustion creates fewer greenhouse gas emissions compared to petroleum diesel. In this biodiesel program, fleets use a blend of biodiesel and petroleum diesel.
2005 - City Light has signed contracts for enough greenhouse gas offsets to match its estimated 2005 emissions, thus reaching its "net zero" goal. The biodiesel program continues, and a new contract with Princess Cruise Lines is signed (to reduce greenhouse gas emissions by switching two ships from diesel to electricity during their stay in Seattle).
What is Biodiesel?
Biodiesel is a renewable fuel that can be made from raw or recycled vegetable oils and animal fats. Biodiesel contains almost no sulfur and using a gallon of biodiesel instead of a gallon of petroleum diesel reduces greenhouse gas emissions which contribute to global warming by 78%.
Seattle City Light Funding for Biodiesel
Seattle City Light is helping pay for the cost of biodiesel in local transportation fleets using trucks, buses, garbage trucks, and ferries. Partnering with these large users of petroleum fuels leverages Seattle City Light's greenhouse gas mitigation efforts by helping to build demand for biodiesel. As demand builds, local production will increase and the price will go down as availability increases. This will encourage more widespread use. We'll get cleaner air and increased opportunities in rural communities where vegetable oil producing crops are grown. Through biodiesel programs like these, and other programs such as shore-side power for cruise ships, City Light intends to offset the equivalent of 200,000 metric tons of carbon dioxide per year starting in 2005.
Biodiesel Projects Funded by Seattle City Light
- King County Metro - Over 300 metro buses are using a blend of 5% biodiesel with 95% ultra low sulfur diesel rather than regular petroleum diesel.
- Washington State Ferries - Three boats on the Fauntleroy, Southworth and Vashon Island runs used a fuel blend of 20% biodiesel and 80% low sulfur petroleum diesel (B20) in a pilot test. Currently the ferries are investigating ways to solve operational problems and restart using biodiesel.
- Seattle's Department of Fleets and Facilities - diesel vehicles have been using 20% biodiesel and 80% ultra low sulfur diesel since late 2003.
- Rabanco (through Seattle Public Utilities) - garbage trucks are now using 20% biodiesel fuel.
Recent City Commitments related to Global Warming and Climate Change
Earth Day 2000 Resolution 30144 commits Seattle City Light to the long-term goal of meeting all of Seattle's electricity needs with zero net greenhouse gas emissions.
Resolution 30316 (2002) adopts a Citywide minimum goal of 7% reduction in greenhouse gas emissions by 2010.
Resolution 30359 (2001) adopts specific actions, strategies and timelines for Seattle City Light to meet its zero net emission goal through energy conservation, new renewable energy, and CO2 mitigation.
What Can I Do?
For Northwest residents, home heating and motor vehicle travel are the two largest sources of direct greenhouse emissions. Electricity consumption represents an indirect source since emissions are produced at the source of electricity generation.
By using energy wisely, conserving resources, and supporting renewable energy our community can help foster a sustainable economy with fewer impacts from global warming and climate change. Often, the same behaviors that reduce climate impacts, such as improving energy efficiency, also save money.
To assist you in these areas, Seattle City Light offers a range of energy management programs and services for residential and business customers. We can also refer you to related programs and services offered by Seattle Public Utilities and others.
Visit the program links listed at left or call 206.684.3800 (residential) or 206.684.3254 (business) for further City Light program information.
For more information on global warming, visit these Global Warming links.