July 1, 2009

The Odd Couple: Renewables and Transmission

Martin Piszczalski, PhD

The tension between the growing number of renewable energy projects and limited transmission capacity is reflected in Washington’s legislative agenda of establishing a national renewable portfolio standard and new transmission lines dedicated to moving renewable energy coast-to-coast. Even if those ideas become law, hurdles to the happy marriage of renewables and transmission remain.

A total overhaul of the U.S. power delivery system, commercial practices, and regulatory oversight is required to accommodate the higher levels of renewable energy expected to be generated over the next decade. Specifically, transmission of the anticipated enormous quantities of renewable energy from coast to coast poses several key challenges and risks that must be mitigated as part of any comprehensive energy plan. The key question is, Can a growing body of renewable energy and a federal transmission plan be forced into what is surely a shotgun marriage?

The Federal Energy Regulatory Commission (FERC) recognizes the challenges posed by bringing electrons from new and disparately located renewable energy sources to population centers. In late May, FERC announced a series of transmission planning meetings that will focus on "wider integration of regional energy resources into the nation’s power grid." In essence, renewable energy generation, principally wind energy, is located where the transmission infrastructure does not exist, and other distributed energy resources are located in transmission-constrained regions.

According to FERC Chairman Jon Wellinghoff, "Planning is one of the three legs on the transmission policy stool — the others are siting and cost allocation — and all are crucial to meeting the goals of assimilating demand resources, renewable energy and distributed generation into the grid for the benefit of consumers."

We believe that the FERC review process currently under way will acknowledge that renewable energy development is changing the traditional energy source and transmission planning process in three principal ways:

• Market push, not pull, is driving project development.

• Longer distances are hindering new transmission capacity additions.

• The intermittency of most renewable energy drags down new transmission line economics.

Together, these planning changes make it unlikely that evolutionary changes alone will enable the nation to reach its ambitious renewable goals. Rather, a more revolutionary approach that includes a proactive, regional approach to wind and other renewable energy generators will be required, as will electric system operation policies and procedures, and electricity market development, to keep access to transmission corridors open (Figure 1).



1.  How the grid is managed. The U.S. electricity grid is divided into three separate management units or “interconnections.” Within each interconnection are further levels of grid operation involving states, utilities, regions, and a host of different regulators. The fractured nature of the grid impedes the efficient flow of energy between interconnections and complicates adding renewable energy to the mix. Source: National Renewable Energy Laboratory