Editor’s note: This is the first part of our three-part series on microgrids. The second part focuses on places where microgrids are already taking root, and the third part looks at the future of microgrids worldwide.
Microgrids make sense for a world where lighter and cleaner is better. Especially if you want to pack an increasingly powerful punch on a destabilized planet with problems.
Traditional gas power plants in miniature, microgrids are evolving into cleantech solutions fueled by solar and wind. They’re more modular and resilient than last century’s sprawling macrogrids. More seriously, they are essential defenses for a dawning age of distributed generation capable of surviving the sudden, expensive superstorms of climate change.
“The main reason for renewable energy microgrids is that they can be relatively independent of the grid and each other,” U.C. Santa Cruz Center for Sustainable Energy and Power Systems director Michael Isaacson told SolarEnergy. “So if a disaster strikes the main grid, there is the possibility that a microgrid may still be functioning. Also, community-scale microgrids can have the effect if leveling out load demand onto the main grid.”
Independent operation is technical and existential, as Isaacson is proving in a joint U.S.-Denmark program to install community-scale microgrids in California, as SolarEnergy‘s Kristine Wong recently reported. Microgrids may connect to macrogrids through points of common coupling (PCC), but they need to be able autonomously shoulder increasingly essential loads using photovoltaic panels, fuel cells, microturbines, smart inverters, and more.
Interest in mobile microgrids is reasonably mounting beyond the military, universities like U.C. Berkeley and multinationals like Siemens, General Electric and ABB Group. The global microgrid summit that recently wrapped at U.C. Irvine featured everyone from Department of Energy officials and MIT wizards to executives from Bloom Energy, Bechtel and others, all mind-melding ways to make microgrids a way of life. Upstart startups like Gen110 and Sunfunder are funding on solar microgrids at home and abroad, while billionaires like Richard Branson and Larry Ellison are turning their private islands into microgrid experiments.
There has even been rumor of a nanogrid invasion — meaning home-sized microgrids — circulating around. Innovations abound, options beckon.
All Sizes Fit All?
“Microgrids can do a lot of different things,” Navigant microgrid researcher Peter Asmus told SolarEnergy. “That makes it difficult to generalize, but it is getting a lot of hype. Two years ago, it was Navigant’s top-selling topic.”
Lately, the hot story has gotten hotter. Navigant’s quarterly Microgrid Deployment Tracker found an increase to 4,393 megawatts of total microgrid capacity worldwide, with 2,874 megawatts from North America — “the world’s leading market for microgrids,” said Asmus. That honor is specifically due to what Navigant’s report described as “the declining reliability of its distribution grid.”
“Our grid is so unreliable, and the power quality we get keeps going down,” Asmus added. “Our tracker gives the U.S. two-thirds of the microgrid market, although data from Africa and developing countries are hard to get. What’s driving microgrids in America is the military, hospitals and colleges.”
But what will drive the microgrid market further is the present challenge of forging a more multidirectional distributed generation infrastructure, as traditional utilities become obsolete. Currently, Greentech Media Research’s report North American Microgrids 2014 found current microgrid operational capacity at around 1 gigawatt, with a majority of generation coming from gas or diesel. It also found that more than half of America’s states have at least one microgrid in operation or development. But homeowners can’t buy them at the store just yet, and not just because of technical difficulties.
“We’re a long way from ubiquitous or even off-the-shelf microgrids today,” Pareto Energy CTO Shalom Flank told SolarEnergy.
“I’ve been in the microgrid business for the last decade, and I’ve never seen as many people talking about microgrids as there are now — but it’s mostly still talk,” added Flank, whose Pareto colleagues presented at the global macrogrid summit at U.C. Irvine. “The technology has some maturing to do, but it’s the business arrangements that are holding us back. How do these local resources fit into a regulatory scheme and an economic model that are basically a century old? And who’s going to take the trusted and essential role that utilities have filled until now? Homeowners, business owners, and institutions all have enough to worry about, without being microgrid experts, and don’t want to put their everyday operations and their own capital at risk. Those roles and institutional relationships and investment resources will take quite a while to work out, before we can have the robust, green, and distributed power systems we want.”
Next: Where microgrids are taking off.
Top photo courtesy of ABB.