How microgrids improve grid reliability and city resilience

Sandy -- yet another major storm to wreak havoc with the utility grid infrastructure on the U.S. East Coast – underscores a compelling reality: the status quo is no longer acceptable in today’s hyper-digitalized economy.

Consider this: The U.S. utility grid was graded a lowly D+ by the American Council of Civil Engineers in 2009. Lawrence Berkeley National Laboratory (LBNL) statistics show that 80 precent to 90 precent of all grid failures begin at the distribution level of electricity service. The U.S. average outage duration is 120 minutes annually and that number is getting worse while the rest of the industrialized world is less than 10 minutes and getting better.

What’s worse, recent evidence corroborates more severe weather is now business-as-usual. According to the Center for Research on the Epidemiology of Disasters, 100 million to 200 million people were affected by weather-related disasters between 1980 and 2009, with economic losses ranging from $50 billion to $100 billion annually.

What’s the answer, if one takes a big step back and takes stock of macro-trends driving business to link higher notions of sustainability with on-the-ground practicality? Enter the microgrid to the rescue.

Microgrids are really just miniature versions of the larger utility grid except for one defining feature: when necessary, they can disconnect from the macro-grid and can continue to operate in what is known as "island mode." Because of this distinguishing feature, microgrids can offer a higher degree of reliability for facilities such as military bases, hospitals and data centers, which all have "mission critical" functions that need to continue to operate no matter what.

Next page: The business case for microgrids