This is part 4 of a 4-part series – see also Myth #1: The Duck Curve limits renewables integration, Myth #2: Excess renewables must be curtailed or stored, and Myth #3: Clean energy increases consumer costs via higher rates.
America’s electric system is at a stark inflection point: coal power plants are operating at all-time lows with growing retirements, natural gas prices are at historical lows while power generation is rising, electricity sales are flattening, extreme weather events are forcing more resilient infrastructure, and plunging renewable energy prices have made low- or zero-carbon sources cost-competitive with conventional fuel sources.
Rapidly reducing greenhouse gas emissions from the electricity sector is now possible without radically disrupting grid operations, costs, or reliability. But the grid will require a more substantial transformation as we rely on higher shares of variable renewable generation. Some critics argue technological, financial, and institutional barriers will prevent significant decarbonization in the electricity sector, or will drive up the costs at the very least. But four common clean energy myths are easily debunked by facts and experience that show a low-carbon energy future is possible without sacrificing affordable, reliable service.
Myth #4: Natural Gas Generation Is The Main Reason For The Decrease In Carbon Emissions
Reality: Renewable energy and energy efficiency have played major roles in the decline of CO2 emissions
According to Energy Information Administration data, US carbon dioxide emissions peaked in 2007 at 2,425 million metric tons and have remained below that level in the years since.
Because of the coincident rise in power sector natural gas capacity, it’s easy to conclude our transition from dirty coal to less-dirty natural gas is the biggest contributor to this decline. However, significant evidence shows the acceleration of renewable energy and energy efficiency contributed far more than natural gas in reducing carbon emissions.
While more natural gas generation (215 terrawatt-hours, or TWh) has been added than non-hydro renewables (approximately 180 TWh) since 2007, renewable generation produces essentially zero emissions, while natural gas still emits roughly half the carbon dioxide that coal does. This means added renewable generation may have twice the impact of natural gas in reducing carbon dioxide emissions when it replaces coal. And that’s only factoring in the downstream emissions from natural gas combustion; when upstream methane leakage is taken into account, natural gas may be just as bad for the climate as coal. Thus, the addition of renewables has had a far greater relative impact in reducing emissions.
Energy efficiency has, perhaps, been an even greater contributor to emissions reductions than either natural gas or renewables. For decades, new appliances, equipment, and building techniques have been enhanced to consume less power while providing the same level or even improved performance. All of this has had a major impact on overall electricity use, which has decreased from 2007 to 2014.
While electricity sales did take a sizeable dip during the Great Recession in 2009 and rebounded after economic recovery in 2010, sales have since turned downward again, despite continued strong economic growth.
Between utility efficiency programs and tightened codes and standards, efficiency efforts have reduced electricity demand by about 200 TWh, and are estimated to have contributed at least a third, if not more, of total emissions reductions to date.
Pulling It All Together
Accurately estimating the cost of electricity sector decarbonization is undoubtedly a difficult endeavor because of rapid cost declines, myriad technologies, market operations, and other nuances. Institutional inertia favoring an outdated system further clouds this picture.
Nevertheless, it is increasingly clear that today’s available technologies and options can successfully decarbonize the electric sector. In order to cost-effectively achieve the goals many states and countries have laid out, policymakers must have the best available information, and use it to guide policymaking.
Moreover, today’s economy is extraordinarily favorable for investment in renewable resources to make the leap policymakers know is necessary to avoid catastrophic climate effects. Low natural gas prices and the proliferation of energy efficiency technologies mean that utility bills will be kept low, providing a cushion for early investment in renewable resources. The cost of money is at an historic low, encouraging renewable developers to invest. And finally, federal tax incentives for solar and wind power are at peak levels.
Avoiding these four common myths about decarbonizing the power sector can help guide analysts and policymakers toward the solutions needed to reach an affordable, reliable, clean energy future.