The American Gas Association (AGA) and the Massachusetts Institute of Technology (MIT) earlier this month issued contrasting pictures of the future of natural gas as a major U.S. fuel source.
Writing in Environmental Research Letters, MIT researchers said current methods of controlling methane emissions, a major source of greenhouse gas (GHG), need to improve 30-90% over the next decade “for gas to be an effective part of the U.S. efforts to reduce GHG emissions.”
Co-authors Magdalena Klemun and Jessika Trancik examined whether gas helps or hurts the fight to reverse climate change and whether it is, as experts have called it, a bridge fuel in the transition to renewables. They concluded that methane leaks vary among operations and geographical locations, and fugitive emissions often are impossible to identify and estimate accurately.
The AGA Foundation issued two reports that examine strategies for direct use of gas products to lower GHG emissions through either advanced technologies or renewable natural gas (RNG), or biogas. AGA CEO Karen Harbert said the combination of “highly efficient gas appliances and using RNG will reduce emissions along the systems” that move gas.
The first study of direct-use technologies was done by Enovation Partners, while the second on biogas was completed by ICF to examine power-to-gas technology. Both studies can “serve as resources for policymakers and stakeholders to use when evaluating options for achieving cost-effective pathways to reducing emissions,” said AGA spokesperson Jake Rubin.
The direct-use technologies study concluded that U.S. residential gas emissions could be reduced by 24% with average net savings of $51/metric ton (mt) of carbon dioxide (CO2). With higher levels of direct technology use, GHG emissions could be reduced 40% at an average cost of $66/mt.
The authors of the Enovation Partners study said they assumed “no technology miracles” were involved. “The natural gas direct-use technologies modeled in this study are either available now or are expected to roll out to market within three years.”
Similarly, the outcomes predicted are not dependent on policy mandates or required levels of emission reductions. Direct-use technologies on the demand side combined with increased use of RNG on the supply side, along with continued reductions of methane emissions on the U.S. pipeline system, will produce “very deep cuts” in residential GHG emissions
The study warns that there is “no one-size-fits-all” approach to GHG emissions reductions, and it confirms the adequacy of an “integrated approach” that uses gas as a key component of the mix that allows consumers to choose what works best for them.
In the ICF study, the potential of RNG is said to provide “meaningful and cost-effective” GHG reductions. It updates earlier work done for AGA in 2011 that examined biogas derived from biomass feedstocks and upgraded to pipeline quality. It looked at the potential of RNG from various feedstocks and their relative emission reduction and cost.
Based on national, regional and local information sources, the ICF estimated that 1.6-2 Tcf of RNG could be produced by 2040, with various scenarios of growth at 1.9-4.5 Tcf annually.
“The RNG resource potential estimates reported here are 90% and 180% increases from the comparable resource potential scenarios from the 2011 study,” ICF researchers noted. The report assumed a wider array of resources for RNG production in terms of different feedstocks and technologies.
Meanwhile, industry analyst Colin Beaney of global software consulting firm IFS predicted that renewables and sustainable energy will attract 85% of all new energy sector investment next year while demand for fossil fuels remains high.
“Even as wind and solar energy are becoming more reliable and cheaper to install, I predict that in 2020 oil and gas will continue to meet around 50% of the U.S. energy demand,” said Beaney, who is global industry director for energy, utilities and resources.
After 2030, Beaney predicted sharp demand cuts in oil and gas, while renewables continue to grow. He also thinks that starting next year more than half the major energy companies will begin to diversify more, although many have already started to do so.
“Traditional oil and gas companies will feel more pressure to build a business that is sustainable in the long term,” he said.