2008 Corporate Responsibility Report

How we are creating a smarter foundation for a sustainable future

Water Conservation and Management

Water is a critical resource that helps power California. Approximately 19 percent of California’s electricity use and 32 percent of the state’s natural gas use (aside from what is consumed by power plants) is associated with water use.

PG&E’s new Gateway Generating Station in Contra Costa County uses “dry” cooling, which results in 97 percent less water and discharges 96 percent less wastewater than a traditional “wet” cooled plant.

Yet, according to the California Department of Water Resources, “climate change is already having a profound impact on water resources as evidenced by changes in snowpack, river flows and sea levels,” and “adapting California’s water management systems in response to climate change presents one of the most significant challenges of this century.”

Recognizing the scope of this growing challenge, PG&E is taking steps to conserve and protect water in our facilities and operations by implementing a variety of water conservation activities and best practices for managing storm-water.

Adopting Alternative Power Plant Cooling Systems

PG&E is implementing a variety of alternative cooling technologies in new conventional power plants to avoid the use of water. In 2008, PG&E completed the Gateway Generating Station, a 530 MW combined cycle natural gas-fired power plant. The plant, which was the first built by PG&E in nearly 20 years, uses “dry” cooling, which results in 97 percent less water and discharges 96 percent less wastewater than a traditional “wet” cooled plant.

PG&E is also using dry cooling at the company’s new Colusa Generating Station, which broke ground in 2008. And PG&E is repowering its Humboldt Bay plant with a new generation facility that will eliminate the need for once-through cooling.

Most conventional power plants rely on water for steam production and cooling. Industry-wide, once-through or other “wet” cooling technologies use groundwater, municipal water or water from rivers and oceans to condense steam to water in the electricity generation process.

PG&E operates two power plants that use once-through cooling: Diablo Canyon and Humboldt Bay. Diablo Canyon is a 2,240 MW nuclear power plant with a maximum discharge limit of 2.5 billion gallons per day. Humboldt Bay, a 105 MW, two-unit fossil fuel plant, has a maximum discharge limit of 76 million gallons per day. The water discharge limits are set in the facilities’ environmental permits.

While the use of water in “once-through” cooling systems can adversely affect aquatic organisms, both PG&E plants that use this method operate under strict environmental discharge limits. In an effort to protect the surrounding aquatic ecosystem, PG&E closely monitors the marine environment by conducting regular studies and sampling required under the Clean Water Act.

As we assess additional sources of renewable and traditional power generation to meet customer demand, we continue to consider impacts to local water supplies as part of our review process in an effort to minimize such impacts.

Water Conservation in Our Facilities

To reduce our water footprint, PG&E completed a targeted water conservation effort at seven high-use facilities last year—exceeding our target by achieving a 5.5 percent reduction in gallons per square foot over the prior year, saving approximately 1.7 million gallons.

Working in partnership with local water agencies, we began by conducting water audits to assess opportunities for both indoor and outdoor water savings. Key strategies included installing low-flow toilets, shower heads and faucet aerators at the sites. We also installed “smart” controllers for irrigation systems at three sites to further reduce water use. Additionally, we replaced the water treatment system for a cooling tower at a site in Oakland, which we expect will save approximately 60,000 gallons of water each year, as well as avoided chemical use and maintenance.

In 2009, our goal is to expand the program to reduce water use by 5 percent across a substantial number of facilities managed by our corporate real estate department.

Helping Our Customers Reduce Water Usage

PG&E is also offering our customers incentives to help make the connection between water and energy savings. For example, for years, customers who purchased energy- and water-saving clothes washers were often eligible for double rewards—rebates from both PG&E and their local water agency—but at double the work; both entities had different rebate application processes.

Last year, that changed when PG&E collaborated with 33 water agencies to develop a combined water-energy rebate for customers. The combined rebate allows PG&E and the water agencies to maximize energy and water savings by providing customers with a clear and convenient incentive to upgrade to an energy-efficient model. In 2008, PG&E saw a 50 percent increase in customer participation.

PG&E is also partnering with local water districts to help customers save water in other ways. Last year, we laid the groundwork for a series of water-saving pilot projects that will run through mid-2009—ranging from installing high-efficiency toilets for low-income customers to exploring how new and emerging technologies can yield water savings at water utilities. The pilot program aims to reduce “embedded” energy, which refers to the energy used to transport, treat and distribute water and wastewater.

Reducing Storm Water Run-Off and Protecting Species

PG&E designed a portable wash station to save water and reduce the risk of vehicles spreading sudden oak death and noxious weeds.

Controlling storm water pollution associated with our operations is an important requirement—protecting sensitive species such as the California red-legged frog and the California tiger salamander during construction activities. Until recently, PG&E used only traditional methods, such as black silt fencing or placing tubular rolls of straw on slopes and around site perimeters and storm drain inlets.

To meet our compliance obligations in a more sustainable way, PG&E now uses an innovative reusable and recyclable fencing, which improves safety and retains twice the sediment at half the cost. To protect the spread of diseases among amphibians, PG&E has also implemented a protocol for cleaning the fencing prior to being reused. Last year, we successfully used this fencing on five projects, including a new wind farm constructed in Solano County.

PG&E is also coupling our storm-water best management practices with efforts to battle the spread of sudden oak death and noxious weeds, which threaten native plants and the habitats they provide. In 2008, we continued to use portable, closed-loop wash stations to clean vehicles and equipment on projects that traversed through sensitive areas.