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Evolutionary directions for electric system architecture.
the wish lists or drawing boards of utilities and system operators. As a result of this stand-off, there’s an increasing scarcity of transmission capacity. This scarcity is acute for system operators in the context of technical control, where thermal limits and stability constraints leave a shrinking range of options for operating the system in a secure “N-1” state— i.e., with reserves sufficient throughout the system to accommodate the loss of any one component at any time. In the context of electricity markets, the same scarcity is observed in the form of geographic price differentials or congestion charges.
If any growth in electric demand is to be sustained at a level of power quality and reliability comparable to that enjoyed at present, and if the present shift to carbon-free generation resources is to continue, some expansion of the T&D system seems inevitable. But arguably there are two fundamentally distinct options for how T&D architecture and operations can grow to accommodate electric customers’ needs: either by traditional build solutions—that is, investment in wires, towers, poles and power plants—or by new and improved T&D functionalities which, through relatively small or novel material, control or software additions, extract new performance from existing hardware and real estate.
This brings the analysis to a critical pair of assertions: First, the ability to physically build out the T&D system by adding significant amounts of copper, steel and aluminum will be primarily affected by public policies and social acceptance. Second, T&D functionalities will be primarily affected by availability, costs, and adoption rates of new technologies. Not coincidentally, these two sets of drivers—in shorthand, policy and technology—are the most uncertain among the broader set of exogenous factors considered above.
Again, isolating technology and policy as mutually unrelated factors is a gross simplification. Nevertheless, the respective correlations expressed in the above assertions—traditional T&D build-out with policy, and new T&D functionality with technology—are both sufficiently strong and sufficiently separable from each other to permit the two pairs to be graphed in orthogonal directions for purposes of the scenario-analysis exercise. Thus two axes are constructed: In the horizontal direction, a continuum illustrates how much new technology is available. At the left end, a paucity of technological development—or adoption—means that T&D functionalities are improved only in small increments, if at all. At the right end, significant technological innovations enable a paradigm shift in new T&D functionalities. In the vertical direction, a continuum illustrates policy, which at the bottom resists and at the top promotes the construction of traditional T&D facilities. The intersection of these two continua, technology and policy, will form the basis for distinguishing future scenarios.
Characterizing the two extremes of each continuum in a bit more detail allows examining the plausibility of each. At the low end of technological development, T&D functionalities would barely improve. The lack of development could be due to intrinsic physical difficulties, excessive risk for T&D owners, operators, investors and regulators, or economic returns that favor incremental improvements over radical innovation or replacement. At the high end, devices and techniques become commercially available and affordable that qualitatively change