Posted on May 16, 2012

PG&E Veteran: Huge Potential for Hydropower Growth

By David Kligman

Balch Afterbay on Kings River

Balch Powerhouse and Balch Afterbay are located on the North Fork Kings River, about 40 miles northeast of Fresno. (Photo by James Park.)

SAN FRANCISCO—Generating electricity from falling water has been around so long that some might not realize it’s as clean and renewable an energy source as solar or wind power.

In fact, hydropower accounts for 8 percent of electricity in the United States. That’s more than double all the other sources of renewables combined.

Yet, by definition in California, PG&E’s hydro powerhouses that produce more than 30 megawatts (representing more than 90 percent of PG&E’s total hydropower) don’t qualify as renewable under the state’s renewable portfolio standards (RPS).

But, says PG&E’s David Moller, all hydropower is “inherently renewable.”

Moller is a director in PG&E’s power generation department and a leader nationally on hydroelectric issues. He was just re-elected as president of the National Hydropower Association.

Hydro Power“If you had a hydro powerhouse on a river somewhere and it was 29 megawatts and right across the river you had another one that was 31 megawatts, one qualifies as RPS renewable and one does not, and yet they’re equally renewable,” said Moller.

Read more about David Moller.

By 2020, the state of California has required that PG&E and other electric utilities get a third of their electricity from eligible renewable sources, such as wind, solar and geothermal. Only small hydro counts (facilities with less than 30 megawatts) toward that RPS requirement as a way to stimulate new sources of renewable power.

Nearly four decades with PG&E

Moller, who has worked for nearly four decades for PG&E, helps run the country’s largest privately-owned hydropower systems, some of which dates to the California Gold Rush.

“It is totally taken for granted because it’s been around for a long time,” Moller said. “Hydropower is such an ingrained part of the power generation infrastructure for PG&E and nationally.”

PG&E’s 68 powerhouses from Redding to Bakersfield provide nearly 4,000 megawatts of safe, reliable and renewable energy—enough electricity to power 4 million homes.

Haas Powerhouse

The Haas Powerhouse, in Kings County, generates 144 megawatts of electricity. (Photo by James Park).

While generating power from water has not changed much over the past century, the rules that hydroelectric operators must follow have. The Federal Energy Regulatory Commission licenses the powerhouses, with each license lasting typically 30 to 50 years. Today, renewing a license requires an incredibly thorough and lengthy review of all impacts to affected resources, especially the land and waterway. This is where much of PG&E’s work takes place—balancing power generation needs with sound environmental stewardship, including the interests of conservationists, area businesses, whitewater rafters and others.

Since 2001, PG&E has completed the relicensing process for nine of its 26 licenses and is currently negotiating to renew seven others.

“It’s very challenging because everybody has different interests,” said Moller. “But PG&E is looked at as a national leader in reaching collaborative agreements. We’re very well known for really working hard to find these balanced solutions.”

PG&E’s hydro powerhouses range in age from 25 to over 110 years, with most built in the first half of the 20th century. Regardless of the age of the facilities, renewing a license involves re-balancing use of the resources in the context of current social priorities.

Balancing environmental interests

PG&E’s Battle Creek hydro facility in Tehama County exemplifies this give-and-take process. Working with federal and state resource agencies, as well as conservation groups, the utility is voluntarily removing or modifying several dams and has agreed to give up some of its hydropower generation to help with the recovery of endangered salmon.

Battle Creek

A construction crew in Tehama County works on a PG&E project to give up some hydropower to benefit endangered salmon. (Photo by David Kligman.)

“We are opening up 48 miles of premier salmon spawning habitat,” Moller said. “It was a case where we produced a relatively small amount of hydropower, but there was the potential to do something really beneficial for the environment.  It’s a great success story and it’s a good example of who we are as a company.”

As president of the National Hydropower Association, Moller actively engages on hydropower issues of national importance.

“My focus is on figuring out how hydropower can help even more to be part of the solution to meet our country’s clean energy goals,” Moller said. “Hydropower is an essential tool in the clean energy toolbox. It already does a lot, and it can do much more.”

Retrofitting existing dams a huge potential

The potential for hydropower growth in the United States is huge, Moller says, in part because most existing dams don’t produce hydroelectricity. Less than 3 percent of the nation’s 80,000 dams have power-generation facilities.

“When people think of hydropower they think of large dams,” Moller said. “And yet there’s tremendous growth potential by basically retrofitting what’s already there, especially the federal dams.”

Retrofitting can include adding hydropower generation to existing non-power dams or efficiency improvements to old equipment to get more power. That’s what PG&E is doing with its 1950s-era Rock Creek powerhouse on the Feather River in Butte County. PG&E is increasing the output by 11 megawatts simply by upgrading the existing equipment.

And, Moller adds, “That 11 megawatts qualifies as RPS renewable.”

For PG&E, Moller pointed to three major themes guiding hydropower operations:

  • Be a responsible environmental steward: “It’s a privilege to be able to use these resources for power generation. And we take that very, very seriously.”
  • Keep the projects running: “From a societal standpoint, it’s a clean way to produce energy.”
  • Grid reliability important: “The operating flexibility of hydropower is essential to grid reliability and integrating intermittent renewables like wind and solar. And hydro pumped storage continues to be the only grid-scale energy storage technology (like Helms, where energy is stored during off-peak hours and can be used during peak periods).”

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