Clean Energy

50%+Percentage of electricity that came from a combination of renewable and greenhouse gas-free resources in 2013

PG&E delivers some of the nation’s cleanest energy. In fact, the carbon dioxide emissions rate from our delivered electricity is about two-thirds cleaner than the national utility average. And, in recent reports, PG&E ranked third among utilities for both our carbon dioxide emissions rate and the amount of renewable energy we provided to our customers. These reports assessed the 100 largest U.S. electric power producers and 32 U.S. investor-owned electric utility companies, respectively. Moving forward, we are actively working to reduce our carbon footprint by increasing supplies of clean and renewable energy, while also maintaining enough conventional generation to fill in when renewables are unavailable.

Our Approach

To meet California’s demand for electricity, the state benefits from a “loading order” of preferred energy sources originally adopted in the state’s 2003 Energy Action Plan. This state-wide comprehensive energy strategy consists of reducing electricity demand through energy efficiency and demand response, and meeting new power generation needs first with renewable and distributed generation resources, and second with cleaner fossil-fueled generation. The loading order serves as the foundation for energy policies and decisions to develop and operate California’s electricity system in the best long-term interest of the public.

PG&E procures resources to meet its customer electricity needs based on a long-term procurement plan that follows the loading order and is approved by the CPUC.

Historically, PG&E’s long-term resource planning has focused on anticipating the growth in electricity demand and determining how to meet that growth in keeping with the loading order. It was generally the case that generating resources such as conventional power plants had sufficient operational flexibility to meet daily variations in energy demand. The primary focus was ensuring that the system could meet peak demand to continue to deliver reliable service.

As increasing amounts of intermittent resources, such as wind and solar generation, are being added, it presents challenges for balancing energy supply and demand. Today, we must anticipate the amount of electricity our customers require as well as the ability of different generating resources to provide electricity at a given time. Today’s electric system needs to be more communicative and more flexible—a challenge we’re meeting by investing in a smarter grid, improving the existing infrastructure and power markets, piloting new approaches to energy storage and integrating more flexible conventional generation resources alongside additional renewables.

Measuring Progress

In 2013, PG&E’s retail customers used 75,705 GWh of electricity. Of that amount, 31,547 GWh were generated by PG&E’s own natural gas, hydroelectric and nuclear facilities, as well as smaller amounts of diesel, fuel cell and solar energy. The remainder was purchased from third-party generators, via either contracts or the open market.

The chart below shows our overall electricity supply mix for 2013, which included both the energy PG&E generated and the energy PG&E purchased from third parties.

PG&E’s 2013 Electric Power Mix Delivered to Retail Customers
  • * “Other” includes diesel oil and petroleum coke (a waste byproduct of oil refining) and “Unspecified Power” refers to electricity generated that is not traceable to specific generation sources by any auditable contract trail.
  • ** As defined in Senate Bill 1078, which created California’s Renewable Portfolio Standard, an eligible renewable resource includes geothermal facilities, hydroelectric facilities with a capacity rating of 30 MW or less, biomass, selected municipal solid waste facilities, solar facilities and wind facilities. These figures are preliminary and will not be finalized until verified by the California Energy Commission.

We also continue to work with our customers to reduce energy demand through a range of energy efficiency and distributed generation opportunities. In fact, between 2014 and 2024, forecasts show PG&E meeting more than 50 percent of the anticipated demand growth in its service area through energy efficiency and generation from combined heat and power and solar at the customer site. As a result of this and factors such as economic growth, electricity sales are projected to grow at an average rate of just 0.3 percent per year between 2014 and 2024.

Composition of Projected Energy Load Growth Met by Demand-Side Resources, 2014–2024

Looking Ahead

PG&E will continue to rely on a wide variety of clean sources of power, including nuclear, solar, wind and hydro, to provide electricity for its customers.

As we move to a smarter grid that integrates more renewable energy sources, the potential role for energy storage technologies is growing—whether in the form of batteries or other devices. This growth is driven, in part, by California’s recently adopted energy storage mandate, which requires electric utilities to purchase 1,325 MW of storage capacity by 2020.

Energy storage may be able to provide some of the increased need for operating flexibility; however, it is too early to tell whether and for what applications additional amounts of storage could be cost-effective. Accordingly, PG&E is exploring emerging storage technologies through a variety of pilot projects.

PG&E has deployed two battery storage systems to test the operational capabilities of energy storage on the electric grid: a 2-MW system at PG&E’s Vaca Dixon substation and a 4-MW system at a customer site in San Jose. These pilots aim to provide critical real-world data on the technical and financial performance of battery energy storage to inform future decisions about how these assets can serve PG&E’s customers.

PG&E is also conducting a feasibility study to demonstrate the viability of advanced, underground compressed air energy storage technology. As envisioned, the project would store large amounts of energy from resources such as intermittent renewable energy that may be generated at times when it is not needed by our customers; this excess energy would be used to power large compressors to store the energy as high-pressure air in an underground reservoir. The air would then be withdrawn to power an industrial turbine and produce electricity when demand is highest.

PG&E is in the first phase of the project, which involves exploring the technical and economic feasibility of a 300-MW facility with up to 10 hours of storage capability using a porous rock structure for energy storage at a location within PG&E’s service area. PG&E has collected geological samples at two locations and has selected one of these sites for an air injection test. By establishing the project’s feasibility, costs and benefits, PG&E is helping to advance a project that has the potential to benefit California and beyond.

Our Sustainability Journey





Economic Vitality