Wayne State University

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Caisheng Wang developing strategy for integrating alternative energy sources with existing power grids

Posted on: Thursday, April 30, 2009

A Wayne State researcher is developing a strategy that manages new and old energy sources in one dynamic, integrated system that's more efficient and reliable than current energy distribution.

Caisheng Wang, Ph.D., assistant professor of electrical and computer engineering and engineering technology in the College of Engineering and resident of Detroit, Mich., received a $311,334 grant from the National Science Foundation to develop a control strategy for using both traditional power plant-generated electricity and alternative energy distributed generation (AEDG) sources including wind turbines, solar panels and fuel cells.

AEDG sources, which could be standard features of smart homes of the future, can generate power on their own for individual homes or as part of a larger network connected by a grid. If utilized efficiently, their integration into the larger power system could bring about vital improvements to the current power system.

"Integrating old and new energy sources into one system is challenging, because the current energy infrastructure was not designed for these small, additional power sources," Wang said. "Yet, if we can develop strategies for managing them together, it will create opportunities for both efficiency and reliability that we've never seen before."

The potential to improve energy efficiency stems from the fact that whenever a home increases or decreases its energy demand - by turning on the washer, or turning off lights, for example - some energy is lost. Additional power sources, such as fuel cells, can absorb these oscillations, making the home's demand on power plant-generated energy steadier - in turn wasting less power. "By the time energy generated in a power plant reaches an individual home in the current system, 9 percent of the energy is lost," Wang said. "If we can decrease that loss by 1 percent, it would be equivalent to needing 15 less coal-fired power plants in the U.S. over the next 20 years.

AEDG integration may also make blackouts less likely, because alternative energy sources can provide back-up support to large-scale power grids. In the current system, if a glitch occurs in a power plant, the plant will automatically disconnect itself from the power grid. That void in energy generation, however, puts an additional load on the remaining power plants supporting the grid, which can lead to large-scale malfunction. By controlling AEDG sources to supply power to the grid when needed, however, blackouts may be avoided.

Wang is modeling his control strategy to include several facets, including coordinating multiple energy sources to optimize efficiency, energy storage and even prediction programs for upcoming shortages or surpluses in energy supply. He will test the strategies using computer simulation studies, and later, using a microgrid that will power the WSU engineering technology building. "If we can successfully manage the power with this microgrid, we'll know we're on the right track to extending the strategy to the larger system where it is greatly needed," Wang said.