Why we need nationwide electric grid in the U.S. but don’t have one

This story is part of CNBC’s “Transmission Troubles” series, an inside look at why the aging electrical grid in the U.S. is struggling to keep up, how it’s being improved, and why it’s so vital to fighting climate change. See also parts 1 and 2, “Why America’s outdated energy grid is a climate problem” and “Why it’s so hard to build new electrical transmission lines in the U.S.″

Building large-scale transmission lines that carry electricity across the United States has the potential to be an extremely cost-effective way to reduce greenhouse gas emissions while also improving reliability of the country’s energy grid.

But the energy grid in the U.S. has developed over decades as a patchwork of thousands of individual utilities serving their own local regions. There is no incentive for energy companies to see the forest for the trees.

“The system we have for planning and paying for new transmission does not adequately value or promote the vital benefits of interregional transmission. Transmission planning does not sufficiently take into account the benefits of a holistic system over the long term,” Gregory Wetstone, CEO of the non-profit American Council on Renewable Energy, told CNBC.

The regulatory framework that has evolved surrounding those local utilities and their electricity transmission processes completely short-circuits when it comes to planning longer, bigger-scale transmission lines.

“Lines crossing multiple states have to receive permits from many local and state agencies, and a single county can block the construction of a new transmission line that would benefit the entire region,” Wetstone told CNBC. “Imagine trying to build the national highway system that we now have if any single county along the way could block the entire project. It simply wouldn’t have been possible.”

The Department of Energy is in the process of conducting a National Transmission Planning Study,to look into all of this. The government’s Pacific Northwest National Laboratory and its National Renewable Energy Laboratory are working on executing that work, but the results of that study will not be published for some time, a NREL researcher told CNBC.

Unless the U.S. can modernize its electric grid and update the regulatory processes surrounding construction of new lines, the country’s climate goals will be harder and more expensive to achieve.

Currently, electricity generation results in 32 percent of carbon dioxide emissions in the United States .To mitigate the effects of global warming, electrical generation needs needs to move from burning fossil fuels, like oil and coal, to emissions-free sources of energy, like wind and solar.

One way of reducing emissions caused…