The case for creating a national energy grid in the United States is overwhelming, according to a new study. After analyzing several potential scenarios, the National Renewable Energy Laboratory (NREL) concluded that bringing together America’s existing three regional networks would produce major benefits for utilities and ratepayers alike.
Currently, the US grid is composed of three largely independent sections: the Eastern Interconnection, Western Interconnection, and Electric Reliability Council of Texas (EROCAT).
Although some linkages between these three regions exist, comparatively little energy is shared between them. In numerical terms, the three grids are connected by no more than 1,300 megawatts of capacity at seven locations.
In preliminary results, the NREL study concluded that there would be many benefits to unifying the grid. These include new opportunities to create large-scale wind and solar power facilities in less populated areas, which would be able to reach larger markets with more effective transmission, as well as more effective resource sharing on a daily and seasonal basis. It would be possible, for example, for solar power in the southwestern US to support peak demand in northeastern states, the research team noted.
The researchers plan to publish their findings in the coming months. The authors of the Interconnection Seam Study, the project’s official title, explain their goal is to “identify cost-effective options for upgrading the U.S. electric grid to create a more integrated power system that can drive economic growth and increase efficient development and utilization of the nation’s abundant energy resources, including solar, wind, and natural gas.”
High voltage direct current
The NREL’s most ambitious proposal involves transforming the three regional grids into a national grid. This could be accomplished by a network of high voltage direct current (HVDC) connections, which would ease the flow of energy across long distances. The alternating current lines that presently link the three regions are ill-suited to transmitting large quantities of energy due to their inefficiency.
In the past, alternating current connections were preferred as a cheaper option to HVDC. But according to Aaron Bloom, who led the NREL study, the direct current option is becoming more affordable due to technological developments.
Moreover, the limited connections between the eastern, western, and Texas grids are between 30 and 40 years old, meaning they’re reaching the end of their useful life spans. Modernization, therefore, appears necessary in any case.
A less ambitious scenario considered by the researchers would see the current level of HVDC links remain the same, but new AC lines added on each side. The analysis also included two further variants: one in which the capacity of current HVDC lines would be expanded, and another that would increase the number of HVDC lines but stop short of establishing a unified national grid.
All the suggested designs were found to reduce electricity costs, while meeting reliability and demand requirements.
The financial benefits would increase significantly if a carbon tax was introduced, the study added. To give an example, every $1 invested in the creation of a national grid would result in $1.14 of benefits, assuming carbon policy remains the same. However, if a $40-a-ton carbon tax was adopted, these financial benefits rise to $2.52 for every $1 of investment.
The NREL study is far from the first to set out the benefits of establishing a national energy grid. In 2016, a study by the National Oceanic and atmospheric Administration estimated that connecting America’s regional grids would cut power plant emissions by 80 percent. Even as far back as the 1920s, plans in support of national coordination were advanced.
However, numerous obstacles mean that even now, many observers doubt it could be achieved.
One challenge is that spending on such projects is typically allocated at the state or local level. Associated with this is the conflicting interests of states and regions, including the question of where the new power lines and transmitting stations would be located.
There’s also the issue of land ownership more broadly. Even if state and federal governments could agree on the need to build a grid, private landowners could oppose it if it involved construction on or near their property.
Lastly, the overall cost of constructing a national grid should not be forgotten. Although it is difficult to calculate precise costs for such a major undertaking, Joshua Rhodes, a researcher at the University of Texas at Austin, predicts that the depreciated value of the current grids is somewhere between $1.5 and $2 trillion.
“To replace it would cost almost $5 trillion,” Rhodes said. “There is no path that does not require investment – even just maintaining what we have will cost hundreds of billions, if not trillions, of dollars over the next decade.”
Jordan Smith is a freelance journalist and translator covering issues related to energy, the environment, and politics. His work has appeared on the independent news site Opposing Views, and at the Canadian Labour Institute.