PG&E Sustainability Report: Emissions Rate Down 12%
Pacific Gas & Electric’s CO2 emissions rate associated with electricity delivered fell 12 percent between 2010 and 2011, to 393 pounds of CO2 per MWh, according to the company’s latest corporate responsibility and sustainability report.
This latest emissions rate was about one-third the national utility average, the company says. The rate takes into account emissions from both PG&E-owned power generation and power purchased from third parties.
PG&E’s total CO2 emissions from delivered electricity in 2011 were the lowest on record—declining about six percent from the prior year to 14.7 million metric tons. This decline reflected an increase in the amount of renewable and large hydro electricity in its power portfolio and the expanded use of cleaner fossil-fueled electricity, such as the first full year of operations for two natural gas-fired plants.
The company says it is on target to meet the current compliance period of California’s Renewable Portfolio Standard, which requires an average 20 percent renewable energy from 2011 to 2013. In 2012, PG&E got 19 percent of its delivered electricity from renewable sources, primarily from contracts with renewable energy companies. The RPS requires 33 percent renewables by the end of 2020.
PG&E reports its emissions as part of California’s cap and trade system, and to the US EPA as part of mandatory federal reporting. The company’s facilities in the nine-county San Francisco Bay Area also pay a greenhouse gas emissions fee of 4.8 cents per metric ton of CO2-equivalent on emissions from facilities such as fossil-fueled power plants, natural gas compressor stations and emergency generators.
The company reduced its sulfur hexafluoride (SF6) emissions nearly 10 percent from 2011 to 2012. SF6 is an extremely potent greenhouse gas, about 23,900 times more potent than CO2 on a per-ton basis, and is used as an electrical insulating material in high-voltage circuit breakers and gas-insulated substations. Since 1998, PG&E has reduced total SF6 emissions by 75 percent, and its SF6 emissions rate by 87 percent.
PG&E says it avoided the release of 258 MMcf of natural gas—or nearly 100,000 metric tons of CO2-equivalent emissions—in 2012. These savings were achieved primarily by replacing older gas mains, and by a technique called cross compression, where natural gas is transferred from one pipeline to another during large pipeline construction and repair projects.
The report is for PG&E Corporation, the parent company of Pacific Gas and Electric Company, which has 20,000 employees and serves 15 million people in northern and central California.
PG&E has a goal to reduce energy use by 15 percent at its offices and service yards by 2014 from a 2009 baseline. At 168 offices and service yards in 2012, PG&E reduced energy use by 3.1 percent – or about 12,990 MMBtus – exceeding its 3 percent target for the year. PG&E says it achieved this by specifying energy-efficient designs when replacing mechanical and lighting systems; installing advanced controls and building automation systems; and incorporating energy efficiency considerations into major remodel projects.
In 2013, its goal is to cut energy use at offices and service yards by 3.5 percent.
PG&E also cut emissions through changes to its fleet. In 2012, the company’s use of natural gas in fleet vehicles saved more than 2,200 metric tons of CO2 on a well to wheel basis.
Nearly 20 percent of the company’s 8,200 on-road vehicles were powered by compressed natural gas, electricity or other alternative fuels at the end of 2012. The company has more than 270 trucks equipped with eWIMS, a plug-in battery system that PG&E developed with Altec Indutries, and the utility plans to increase that number to 700 by 2017.
In 2012, it expanded its fueling network to include more than 150 charging stations at about 40 locations. The company also maintains a network of more than 30 CNG facilities, 25 of which are open to customers.
PG&E says there are four main potential climate risks for its sector:
- Increased electricity demand from more extreme and frequent hot weather events.
- Reductions in hydroelectric generation due to reductions in snowpack in parts of the Sierra Nevada Mountains. The company’s strategies for adaptation to snowpack reduction include developing new modeling tools for forecasting runoff, maintaining higher winter carryover reservoir storage levels, reducing conveyance flows in canals and flumes during winter storms as more precipitation falls as rain, and reducing discretionary reservoir water releases.
- Increased wildfire risk. The threat of wildfires to electricity supply was demonstrated in August, when the Rim Fire in Yosemite National Park forced the closure of transmission lines bringing electricity to San Francisco. The city actually turned to PG&E to help make up the shortfall.
- Impacts to facilities due to sea level rise and increased storm surges. Scientists project that sea levels along California’s coast will slowly rise by a meter or more within this century, which may result in higher flooding potential at PG&E’s low elevation facilities, the company reports. PG&E is working with the California Energy Commission and the University of California, Berkeley to study the effects of sea-level rise and water flow around its natural gas storage facility and infrastructure at McDonald Island in the Sacramento River Delta.
The company has an in-house climate science team that regularly reviews the scientific literature on how sea level rise, temperature changes, rainfall and runoff patterns, wildfire risk, and storm frequency and intensity affect California and the West.
The company does not report a total amount of water used, but taking together the various points of water withdrawal that it lists in the report, EL PRO calculates that PG&E withdrew almost 834 billion gallons in 2012, down 3.5 percent from 2011 and 4.7 percent from 2010. By far its biggest use is the Diablo Canyon plant, which in 2012 used over 833 billion gallons of saltwater for once-through cooling and almost 150 million gallons of domestic and process water.
PG&E does not use freshwater for once-through cooling for any of its power plants. All its thermal plants except Diablo Canyon use air-cooled technology.
For example, the company says it uses advanced reciprocating engine technology at the repowered 163 MW Humboldt Bay Generating Station. Because this plant is cooled with air radiators using a closed loop liquid coolant, it requires minimal water use.
PG&E is using another dry cooling technology, an air-cooled condenser, at the Gateway and Colusa Generating Stations. The Gateway Generating Station uses about 97 percent less water and discharges 98 percent less wastewater than a traditional “wet” cooled plant, and the similarly designed Colusa Generating Station uses a zero liquid discharge system that recycles wastewater. Fluctuations in water use at these facilities are largely attributable to plant maintenance activities.
PG&E notes that EPA regulations expected this year will include specific compliance requirements for impingement (when organisms are caught on water filter screens) and entrainment (when organisms are drawn in through the cooling system).
In 2012, PG&E says it used a “significant” amount of water to perform hydrostatic testing on more than 175 miles of its gas transmission pipelines to verify the safety and reliability of its natural gas transmission system – but it does not specify this amount.
For its 135 offices and service yards, PG&E met its 2 percent annual water reduction goal in 2012, and is on track to meet its five-year goal of a 20 percent reduction by the end of 2014. To achieve these reductions, the company reduced landscape water use, in part by installing “smart” irrigation controllers at 11 sites.
In 2013, its goal is to achieve an additional 2 percent reduction at the 135 sites.
In 2012 PG&E reached a 78 percent waste diversion rate for 48 sites, exceeding its 73 percent target. This total includes all non-hazardous municipal waste generated within and outside the buildings. Key steps included ensuring yard bins were the right size, upgrading service and adding composting and single-stream recycling at select locations. The company’s 2013 goal is to achieve an 81 percent waste diversion rate, and it will aim for a 61 percent diversion rate at an additional 67 sites.
Last year the company recycled more than 2 million pounds of recovered meters; 15 million pounds of transformers; 147,000 pounds of plastic, including pipe and hard hats; and more than 23 million pounds of scrap iron, aluminum and copper from conductors, meters and miscellaneous material. It also recycled or reused nearly 150 tons of e-waste, including consumer electronic devices, CPUs, monitors, servers, printers, and other equipment.
Compliance and enforcement
PG&E reported a total of 182 releases in 2012, a decrease from 242 reported in 2011. The company says a large percentage of these releases involved small amounts of mineral oil used in transformers or other petroleum-based substances.
It reported six permit exceedances in 2012, compared to one in 2011.
Last year, PG&E paid $3.6 million to resolve an alleged violation of a 2008 Clean Up and Abatement Order issued by the Lahantan Regional Water Quality Control Board, regarding a chromium plume in Hinkley, Calif. The alleged violation relates to the spreading of the Hinkley pollution plume made famous in the film Erin Brockovich. PG&E paid $333 million to end the original lawsuit, KPCC reports.
In 2012, PG&E also paid a total of $170,360 in settlements and penalties stemming from nine environmental enforcement actions.
Last year PG&E implemented what it describes as a “one-stop shop” for managing environmental permitting and compliance requirements for gas, electric and energy supply construction projects. It implemented a new project management system that will allow all environmental permits and requirements to be centrally tracked, and began to implement an automated environmental screening tool to help assess potential environmental impacts. It also finished implementing an Enterprise Compliance Tracking System to clarify roles and responsibilities for environmental tasks at the facility level. PG&E has implemented the system at all facilities that support its gas and electric distribution lines of business, and says it has seen a significant improvement in compliance at these facilities.
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