The community of Blue Lake Rancheria, a Native American reservation in Northern California, has partnered with Pacific Gas & Electric (PG&E) to create a community microgrid that will deliver clean and reliable power to businesses, government buildings, and a Red Cross emergency shelter. Siemens, a world leader in smart grid and energy management technology, will provide the hardware and software controls. PG&E will ensure that the microgrid interfaces with the larger utility grid, and its engineers will conduct a case study to see how microgrids with renewable energy can be deployed and maintained. Rounding out the partnership is the Schatz Energy Research Center at Humboldt State University, whose engineers will oversee the design and installation of the microgrid. As a bonus, its students - undergraduate and graduate - will gain valuable real-world experience by working on the project.

Efficiency First

The microgrid represents the second phase of Blue Lake Rancheria’s efforts to go green. Over the past few years, the community has invested in a variety of energy efficiency upgrades that reduced its energy consumption by an impressive 35%. The reservation now includes sustainability in all of its projects, from recycling to energy to green building practices. These efforts are more than “feel good activism” - they make economic sense too. “The paybacks for the energy efficiency upgrades the Tribe has implemented to date are all under three years, and most are under a year,” said Jana Ganion, Blue Lake Rancheria’s Energy Director.

In 2014, Blue Lake Rancheria was recognized by the White House as a Climate Action Champion, one of only sixteen communities to earn that honor.

Power Generation and Energy Storage

One goal of the project is for the microgrid to generate roughly half of the energy needed by the facilities using clean, renewable sources. A 500 kW photovoltaic array will convert sunlight into over 900 MWh of electricity every year, and an innovative biomass processing facility will convert sawdust and other clean waste into hydrogen for fuel cells. Fuel cells can be used for storage - typically using electrolysis to extract hydrogen from water (energy storage) and combining hydrogen with oxygen to generate electricity. Electrolysis is not a very efficient process, so a better use of fuel cells is for production rather than storage. In that case it’s common to extract hydrogen from fossil fuels, which is cleaner than burning the hydrocarbons but not exactly renewable. The Blue Lake Rancheria’s fuel cells will produce clean, renewable power using biomass as its source of hydrogen.

During peak sun hours, excess energy will charge a one MWh battery bank. Since the microgrid will be tied to the PG&E main grid, any power generated that’s not used and can’t be stored will be sold to PG&E under a net-metering agreement. Rather than seeing distributed generation as a threat to the utility, PG&E is using this as an opportunity to learn more about incorporating renewable energy onto the grid.

Blue Lake Rancheria is a designated Red Cross emergency shelter, and as such it needs a  source of reliable power that can operate in the event of a long-term grid outage. After a catastrophic event, diesel generators will come online to supplement the green energy from solar, storage, and fuel cells. Among other uses, the shelter will employ microgrid energy to create clean drinking water for emergency use. Water is the main byproduct of fuel cells, and electricity from other sources can also power reverse osmosis and desalination equipment.

The Controls

Siemens’ Spectrum Power Microgrid Management System (MGMS) will choreograph the flow of power to and from the microgrid and its components. The MGMS is a fully automated control system that uses weather forecasts, load analysis, and real-time price monitoring to determine when to buy, sell, or store electricity. It’s capable of optimizing for monetary performance (Economic Mode) or for minimal carbon emission (Green Mode). And of course, the MGMS can perform anti-islanding to prevent the microgrid from sending power to the grid during a grid failure.

Images and video courtesy of Siemens