Preface. Renewables are not evenly distributed. Just 10 states have 80% of hydropower (Homeland Security 2011), 10 states produce 75% of wind power (EIA 2017), and 10 states produce 79% of solar power (CE 2020).
With a national grid, instead of having to curtail power so the grid isn’t overwhelmed, the power could be sent places needing electricity, especially entire South East, which has very little commercial-scale wind year round (Friedemann 2015).
But there is no national grid in sight (St John 2020) for many reasons listed below — the extremely high cost, the chance that this would actually make the grid more unstable and lead to a national blackout, NIMBYism at every level, and bureaucracies.
A national supergrid is seen as essential for integrating renewable power into the electric grid, since many regions of the US have limited renewable power options and a very large grid is needed to keep it in balance, since the wind isn’t blowing and the sun isn’t shining everywhere at once, nor do vast regions have hydropower, geothermal, and other renewable power at all.
Just as many natural gas and oil deposits are stranded and unexploited because the cost to build pipelines to them is too high, many renewable resources are unable to generate enough power to justify building transmission lines to them, or they’re too far from cities.
If America tried to balance intermittent power over a wide area like Denmark and construct a national grid, there is the potential for a national blackout.
Although large regions can increase stability, this isn’t always true, since operators can’t see adjoining systems well enough to detect impending extreme events and take countermeasures quickly (CEC).
Size doesn’t always increase reliability because it provides multiple paths for local disturbances to propagate, which can lead to complex chains of cascading failures (Morgan).
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