CAMRA mulls battery project on Mokelumne River

Research underway for pumped-storage hydropower project

Marie-Elena Schembri, Calaveras Enterprise, March 2, 2023

At a Calaveras Amador Mokelumne River Authority (CAMRA) board meeting on Feb 16, Nicholas Sher of GreenGenStorage was given the floor to present on GreenGenStorage’s proposed Mokelumne River Battery Project, which aims to generate and store “clean” energy using existing infrastructure and an open-loop pump system that pumps water through an underground tunnel between two reservoirs.

The project is currently in the planning phase but is already facing scrutiny by environmental groups, community members in both Calaveras and Amador counties, and political leaders who want to know how it is being funded, what the benefits are, and what the effects will be on recreation and the ecosystem of the Mokelumne River, which became a protected Wild and Scenic River System in 2018.

CAMRA is a joint powers authority that was formed in 1999 to address water issues involving both Amador and Calaveras counties. The group is made up of officials and representatives from several water utility managers including Calaveras County Water District, Calaveras Public Utility District, Amador Water Agency, and the Jackson Valley Irrigation District. Calaveras County supervisors Jack Garamendi and Amanda Folendorf both serve on the board.

CAMRA’s mission is “to secure dependable, affordable water and power by preserving the Mokelumne River and watersheds, protecting the water rights of Calaveras and Amador counties, planning for current and future use/demands and negotiate maximum use with non-member entities.”

Project history

The Mokelumne River Battery project was first brought to the table over 15 years ago. PG&E sought out a preliminary Federal Energy Regulatory Commission (FERC) permit to begin researching the project in 2008.

In 2011, PG&E agreed to requests to create and evaluate computer modeling to determine possible temperature changes as a result of the project. The agreement was negotiated in response to PG&E’s request to the California Public Utility Commission (CPUC) to allow the utility company to pass on costs of over $30 million dollars to ratepayers to fund the necessary studies and the rigorous Federal Energy Regulatory Commission (FERC) licensing application process for the project.

The preliminary period is usually up to three years, but can be extended, and allows a FERC license hopeful to complete feasibility studies and gather data necessary for filing the application while having a priority over any other new projects for that site. During the pre-filing stage, a proposal is filed, and then input is sought from the public, indigenous tribes, organizations, and local, state, and federal government resource agencies.

From this input, environmental and other needs are assessed and a study plan created, before going on to create the detailed application which includes proposed mitigation measures. However, PG&E did not complete its application, and a second extension of its preliminary permit in 2014 was denied, thus opening the site up for development again.

Now, Sher and his company GreenGenStorage are looking to re-launch the project as a way to meet California’s long-term energy storage needs and clean energy goals through “carbon-free” open-loop pumped-storage hydroelectricity.

GreenGenStorage first applied for a preliminary permit in 2016. In April 2022, GreenGenStorage submitted its Pre-Application Document (PAD), outlining the project that “would entail construction of a new powerhouse to accommodate a 400 megawatt (MW) Project, a new power tunnel extending from one of the two Bear Reservoirs to the powerhouse, and a tailrace that extends from the powerhouse to the existing Salt Springs Reservoir,” as well as new transmission lines to send energy created to the existing grid at Salt Springs.

The project would utilize existing infrastructure on Salt Springs Reservoir on the North Fork of the Mokelumne River—part of Pacific Gas & Electric’s (PG&E) Mokelumne River Project No. 137 that also encompasses hydroelectric power stations at Electra, West Point, and Tiger Creek—to pump water up from this lower reservoir to either Lower or Upper Bear River Reservoir through a tunnel up to 20,000 feet long.

The project would include the building of an underground powerhouse equipped with reversible pump turbines, which GreenGenStorage says could provide 8-10 hours of energy storage. Water pumped uphill using solar and wind-generated power can be stored in the upper reservoir and later released when needed downhill. According to GreenGenStorage, the project can provide anywhere from 400 and 1200 megawatts (MW) of clean energy, “depending on the state’s energy needs, engineering design, and environmental considerations.”

“This Project will utilize energy produced by renewable resources during times of high production when the energy might not be needed to serve load, and then deliver the energy back into the grid at a time when load exceeds renewable energy supply,” GreenGenStorage states.

GreenGenStorage reports that benefits of the project include reducing greenhouse gas emissions by providing carbon-free electricity, meeting the state’s energy and emissions goals, and creating hundreds of construction jobs and approximately 10 permanent jobs (this number has been reduced from an initial estimate of 40) as well as providing “local economic stimulus throughout project development and operation.”

The PAD lists dozens of local and statewide stakeholders which it has held meetings with or otherwise engaged in the process since the preliminary permit was issued in 2017. These include 12 regional Native American tribes, Amador Water Agency, Calaveras County

Water District, Upper Mokelumne River Watershed Authority, Pacific Gas & Electric Company, Calaveras and Amador county supervisors, California Department of Fish and Wildlife, Natural Resources Defense Council, Foothill Conservancy, Friends of the River, East Bay Municipal Utility District, California State Water Resources Control Board, and the United State Forest Service.

In February 2021, a four-year extension was granted (retroactively) to GreenGenStorage’s preliminary permit, which is set to expire in November 2024.

Earlier versions of the PAD were sent to stakeholders, and GreenGenStorage revised the PAD in February 2022 based on comments received. In September of 2022, GreenGenStorage filed their 400-plus-page Proposed Study Plan (PSP) which covered “20 detailed studies across six topic areas,” according to Sher. It was then amended and revised yet again to address hundreds of stakeholder comments.

Criticisms of the project plan by local conservation groups including Foothill Conservancy, California Sportfishing Protection Alliance, American Whitewater, and Friends of the River called attention to several areas of concern.

These groups banded together to ask GreenGenStorage to make specific additions, including extended studies to determine possible traffic interruptions, impacts on recreation, cultural and tribal resources, wildlife, including threatened and endangered species, and other environmental concerns.

Questions have also been raised about the ethicality of project management, as Sher worked as a lawyer for the California Public Utilities Commission (CPUC) at the time he became involved in managing GreenGenStorage. Sher stepped back from the management role in 2016, handing the reins over to his brother Jonathan, until after he retired from the CPUC.

Sher was also sued by a former business partner, Edward Cooper, in 2020 for breach of contract, in which Cooper claimed Sher had reneged on a agreement “to go into business together on a 50/50 ownership basis with respect to certain green energy opportunities.” The case was later dismissed.

Who is GreenGenStorage?

GreenGenStorage, LLC, was registered as a Limited Liability Company on May 16, 2016, with Nicholas Sher, an environmental lawyer from Oakland, listed as agent. Another company owned by Sher, GreenGenFutures, was established in January 2022.

GreenGenStorageStorage’s website states, “GreenGenStorage is a California-based development team with specialized and highly skilled regulatory, legal, siting, permitting, and finance experience in the energy sector. The executive team has over 60 years of combined experience evaluating energy projects in the public and private sectors.”

It also states, “The GreenGenStorage team includes the following companies providing engineering, stakeholder engagement, and environmental planning technical expertise: McMillen Corp., Stantec, Sequoia Environmental Services, Kleinfelder Kearns & West, G.E. Energy Consulting.”


Why the Mokelumne Battery Project?

After presenting a slideshow overview to the CAMRA board, committee members tossed Sher a slew of questions regarding the project.

“Why the Mokelumne Battery project? The project makes a lot of sense to us, mainly because it takes advantage of existing infrastructure and minimizes impacts to the environment and to people,” said Sher.

The project, according to Sher, would help California “decarbonize the grid” through “non-consumptive use of water.” Additionally, he says GreenGen’s project would “support California's energy and climate goals by integrating renewable energy resources and balancing reliability.”

If approved, construction on the project may not begin until 2026.

Who’s paying for it?

At the CAMRA meeting, Sher was asked where GreenGenStorage is getting its funding.

“We have a private investor that…has helped basically me and my brother. I pulled out money on my house to get this started, and we have an investor that is helping us fund the permitting at this point,” said Sher, before adding that the company is looking into tax credits and applying for a loan with the Department of Energy to help cover construction costs, which Sher estimates could be more than $1.2 billion based on pre-inflation cost analysis.

Calaveras County supervisor and CAMRA vice chair Jack Garamendi said to Sher, “I'm assuming it's not you and your brother [who came] up with $1.2 billion. Are you willing to tell us who your partner is backing this?”

Sher stated that the financial backer, an American company who “build(s) infrastructure” throughout the states, does not wish to be identified—yet. Eventually, according to Sher, the information will have to be revealed when the company files for a Department of Energy loan. Sher said he expects to receive $200-$400 million in equity, and the rest will be debt.

“Remember I asked you this last time, too. When people aren't transparent, it makes people question who's backing things. It might be you might have Saint Theresa backing you up, but we don't know that, so you might want to work on that,” Garamendi told Sher.

Garamendi also drilled Sher on an earlier statement that either PG&E or GreenGenStorage will operate the project. He asked Sher, “What do you mean by that?”

Sher stated they would either hire PG&E to “operate the project,” which is using existing PG&E property and infrastructure, or GreenGenStorage would hire their own engineers to operate it.

Garamendi asked if PG&E was an investor in the project, and Sher stated that they are not, though he is not opposed to selling part of the project to the power company.

“Whatever makes the most sense,” said Sher.

Sher also answered questions about sales tax that Amador and Calaveras counties would split 50/50 for any equipment purchased and assured the board he would be seeking out all of the necessary approvals for road maintenance. Sher stated that the company is in negotiations with PG&E about leasing non-consumptive water rights and open to working with others who have water rights.

Pumped-storage hydropower

According to the United States Department of Energy’s (DOE) U.S. Hydropower Market Report in January 2021, “Pumped Storage Hydropower (PSH) contributes 93% of grid storage in the United States and it is growing nearly as fast as all other storage technologies combined, and PSH “continues to be the preferred least cost technology option for 4–16 hours
duration storage.”

At the time of the report, 67 pumped storage projects were at some stage of evaluation or development, while another 43 were already in operation throughout the United States.

All of the 43 PSH projects already in operation are open-loop systems, most of which were initiated decades earlier. Open-loop pumped-storage projects, like the Mokelumne Battery project, continually draw from a natural water source like a river or stream, and thus have greater environmental impacts than closed-loop projects. Most recent PSH projects, however, have been closed-loop systems that would rely on already existing reservoirs not connected to natural water features or create new reservoirs using groundwater or surface water.

A 2020 study by the Pacific Northwest National Laboratory under the DOE’s HydroWIRES Initiative, took a look at the environmental risks of open-loop versus closed-loop projects. The report found that open-loop systems created greater impacts on surface water quality and aquatic ecology, terrestrial ecology, land use recreation, visual resources, and cultural resources than closed-loop systems.