Infrared satellite image of Aliso Canyon methane leak, courtesy of NASA.
In December of 2019, Berkeley became the first city in the United States to ban natural gas hookups in new construction. Since then, more than 50 cities and counties in California have adopted their own “reach codes” (a regulation that goes beyond the state’s required building codes) to ban natural gas use in some form.
California has relied on natural gas to produce electricity and provide space and water heating for millions of residents for decades. For years, the industry has promoted natural gas as the cleanest fossil fuel. Some even predicted it would be the new clean alternative to gasoline in cars.
Now the state is actively working to reduce our consumption of natural gas. The California Public Utility Commission (CPUC) is working on a long-term plan to phase out natural gas use in buildings. Why, suddenly, is the natural gas industry facing restrictions on where it can be used?
A hint: natural gas is not as clean as we have been led to believe.
Natural gas is a fossil fuel formed by the decay of plant and animal material beneath the earth’s surface. Like oil, it is found in the cracks and spaces between layers of rock. Natural gas reserves are often found with oil deposits, and for many years, drilling companies have “flared” or burned off natural gas to get at the heavier crude oil.
In recent years, advances in horizontal drilling and fracking have allowed producers to access vast natural gas reserves. New techniques have also reduced the cost of extracting natural gas from shale deposits in the United States. These advances led to an industry boom, created jobs, and held the promise of reducing America’s reliance on foreign energy.
However, this boom was not without consequences. The fracking process can pollute both surface and groundwater, among many other local environmental impacts.
And while it’s true that burning natural gas creates less pollution than burning coal or oil, the extraction and recovery process also releases vast amounts of unburned natural gas are directly into the atmosphere. Methane (CH4), the main component of natural gas, is a potent greenhouse gas that, according to the Intergovernmental Panel on Climate Change (IPCC), has a Global Warming Potential (GWP) 28 times greater than carbon dioxide. Other greenhouse gasses have a higher GWP than methane, but none have the same impact due to the massive amounts released. Scientists estimate that methane releases drive 20 to 25 percent of today’s global warming.
Studies indicate that methane releases during natural gas extraction and production add over 13 million metric tons to the atmosphere each year. Modern detection systems have determined the emissions from methane are 60 percent greater than the previous estimates from the Environmental Protection Agency (EPA).
Natural gas leaks aren’t just a problem during production. In California, the underground gas distribution system is vast and aging. In 2010, a pipeline explosion in San Bruno killed eight people and injured dozens more. The blast destroyed over 3,500 homes and left thousands homeless. Pacific Gas and Electric (PG&E) was eventually convicted of six felony charges and levied over $3 million in fines in connection with the disaster.
On October 23, 2015, Southern California Gas (SoCalGas) discovered a natural gas leak at Aliso Canyon, a vast underground storage facility in the San Fernando Valley that serves the greater Los Angeles region. The leak was caused by a damaged wellhead deep within the facility. Capping the damaged well was challenging and required multiple attempts before it was successfully capped on February 11, 2016, more than three months later. The Aliso Canyon event has the distinction of being the most significant documented leak of methane in the United States. Ninety-seven thousand one hundred (97,100) metric tons of methane were released into the atmosphere. The heat-trapping effect from this single event was the same as the annual emissions from 600,000 cars!
These events prompted the use of new technologies to monitor methane emissions. Using these new technologies, scientists discovered the methane leaking from the transmission and distribution system was far greater than their worst assumptions. In some regions, leaks during natural gas transmission and distribution make it more harmful to the environment than burning coal.
Given these facts, it’s clear we can no longer think of natural gas as a clean “bridge fuel.” In recent years, California has committed to reducing GHG emissions dramatically. Senate Bill 100, which passed in 2018, set a goal of all electricity in the state being supplied from carbon-free sources by 2045. To meet this goal, it’s clear that natural gas must be phased out quickly.
Reducing our dependence on natural gas will require changes to most sectors of the economy. One advantage we can leverage in California is our abundance of sunny days. Solar photovoltaics are providing more and more clean, carbon-free electricity to the distribution grid. The reduced cost of solar panels and utility-scale renewable generation feeds loads of carbon-free electrons to the grid. Wind power helps too. Overall, the carbon-free generation on the grid is getting cleaner faster than experts predicted.
Electrification of the transportation system is a given. Electric cars are proving to be a viable and superior option to internal combustion vehicles. That new electric car you have been considering will likely be the only option in a few short years.
The industrial sector is more challenging. Some industrial processes can substitute electricity over fossil fuels. Others will likely take decades and new technologies due to their specific demands.
Agriculture needs to change as well. Using animal waste to produce biogas is one example of innovation that can reduce the greenhouse gas impacts of farming.
Compared to these challenges, converting buildings to all-electric is comparatively easy. The technology exists and is well established. In most cases, the electric options are more efficient and can perform better than the fossil fuel alternatives. If you watch residential rebates in California, it won’t take long to see where the state is putting its money. The state is currently rolling out multiple rebate programs statewide promoting electric heat pump technology. Electric heat pumps can make domestic hot water and provide space heating and cooling. Heat pumps are far more efficient than natural gas water heaters and furnaces. And if sized and installed correctly, they will offer better performance too.
Natural gas has had a good run for decades in the state. But it turns out it is not as clean and as safe as we have been led to believe. Meanwhile, the electric grid is getting cleaner every day due to renewables. And it looks like electricity will be the clean energy source of the future.
Berkeley and forty-nine other cities and counties have banned natural gas because there is no way to meet the state’s aggressive greenhouse gas reduction goals if we continue to rely on it.
We are in the midst of an energy transition. Fossil fuels are on the way out, and carbon-free electricity will be the energy choice of the future. Natural gas bans in residential applications are intended to speed up this process. It’s really that simple.
Charley Cormany
Executive Director
