EIA study finds cost, efficiency benefit in high-voltage power lines for integrating renewable sources

While contending that the existing grid has limits, a new study from the U.S. Energy Information Administration (EIA) determined that high-voltage direct current (HVDC) power lines could be configured to meet renewable integration with a number of benefits.

Those benefits include cost effectiveness, lower electricity losses, and resistance to overloads that helps cut down on cascading failures throughout the grid. The latter is a real issue to consider, given that under and over-production of electricity during times of high or low system demand are a battle during the increasing deployment of what the EIA labels “non-dispatchable renewable resources” into the grid.

Non-dispatchable renewables are those sources, like solar and wind energy, that are at least somewhat dependent on naturally occurring resources, therefore possessing a limited ability to respond to system operators’ dispatch signals. Their usefulness to the grid also is not helped by the fact that some of them, like wind, tend to be geographically limited in usefulness. There are also dispatchable renewables, which can be used to effortlessly increase or decrease output, as in the cases of geothermal or biomass resources.

HVDC lines could also help move wind-generated power from their generation area — often remote areas away from high demand sites — and bring them to where they are needed. The EIA concluded that the per-mile cost for creating such lines would be between $1.17 million and $8.62 million.