California's Complicated Relationship with Natural Gas

October 13, 2015 | 3:46 pm
Laura Wisland
Former Contributor

Two-thirds of U.S. states may be at risk of relying too heavily on natural gas to meet electricity demand, according to a new analysis from the Union of Concerned Scientists. Why, might you ask, is California, a national and global leader in the move to clean energy, included in that mix of at-risk states?

The UCS analysis assesses states’ overreliance on natural gas that could expose electricity customers to financial risk and prevent states from making deeper reductions in greenhouse gas emissions over time.

While each metric looks at a dimension of state natural gas overreliance, adding it all up makes for a pretty interesting picture of risk. (And the animated version is even more fascinating.)

While each metric looks at a dimension of state natural gas overreliance, adding it all up makes for a pretty interesting picture of risk. (And the animated version is even more fascinating.)

California’s complicated relationship with natural gas

California has more online natural gas generation capacity than any other state except Texas. Part of the reason for that is simply because California has such a large population to serve. This gas fleet supplies a large portion of electricity needs: nearly 60 percent of in-state electricity generation in 2014 came from natural gas.

And yet, California has made great strides to reduce its reliance on natural gas, and fossil fuels in general. Renewable energy production has ramped up significantly in recent years, and is now supplying about 25 percent of the state’s retail sales—and lowering reliance on natural gas.

As far back as 2006, the state enacted Assembly Bill 32, which established a program to reduce greenhouse gasses throughout the economy. And Senate Bill 1368, passed the same year, phases out the state’s long-term coal investments.

Just last week, Governor Jerry Brown signed Senate Bill 350 into law, which requires the state to double energy savings in buildings and rely on renewable sources to meet half of its retail electricity needs by 2030.

Natural gas and renewables should complement, not compete with, each other

California’s natural gas fleet provides an important source of generation capacity and flexibility, which can be relied on when renewable energy is not readily available. But the state has to make sure that natural gas doesn’t crowd out renewable energy on the grid.

If large quantities of renewable energy and natural gas resources are generating electricity at the same time, supply could exceed demand, forcing grid operators to curtail some of the excess renewable electricity to maintain grid stability.

That issue—how to use natural gas in smart way—was the subject of a recent UCS analysis. When we looked at scenarios of 50 percent renewable energy on the California grid, we found that renewable energy curtailment will be exacerbated if grid operators continue to rely upon gas for fast-acting grid reliability services. This is because these gas plants have to be online and generating at all times to provide many of these services, crowding out renewables and generating global warming emissions and air pollution.

energy-graphic-renewable-energy-curtailment-scenario-graph

Fortunately, many of the non-fossil grid management that exist today—demand response, storage, even renewables—are capable of offering grid reliability services; several are able to respond even faster than a natural gas plant. Our 50 percent renewables report shows how we can take advantage of non-fossil sources of flexibility to integrate larger quantities of renewables and maintain grid reliability.

Cutting natural gas overreliance

California’s natural gas fleet has helped the state bring on large quantities of renewables in a relatively short timeframe and reduce reliance on imported coal. And although this fleet will continue to play an important role providing power and reliability to the grid, the additional investments we make in non-fossil grid reliability services will help us minimize our use of natural gas and maximize renewable generation potential, which will help the state achieve our long-term carbon reduction goals.