Why Microgrids Are Smart  

Cleantech.com has an article on the benefits of microgrids - Why Microgrids Are Smart.

A few weeks ago, intelligence agencies and IT security consultants became intimately familiar with something called Stuxnet. Stuxnet is a computer virus that monitors and can reprogram industrial systems such as SCADA, a common system used to manage the electrical grid. Like most computer viruses, the origins and purpose are a bit unclear, though many have speculated that the virus targeted Iran and the country’s suspected nuclear program.

What does any of this have to do with cleantech? A lot, in fact. First, it illustrates the fears many have had about the susceptibility of our power grid to cyber attacks. The Department of Energy has been increasingly aware of these dangers, recently awarding $30M to improve cyber security.

Second, and less obviously, it is another selling point for microgrids. Microgrids are localized mini-grids that have their own generation sources (often solar), can be paired with storage, and are connected to the larger (or “macro”) grid. Picture, for example, a mall with rooftop solar panels providing power to the retail shops when it’s needed, selling excess power back onto the grid when it’s not needed, and buying power from the grid if necessary to supplement the mall’s energy usage.

While touting the advantages of the microgrid is worthy of a blog post unto itself, let me briefly point out a few benefits here. Microgrids can dramatically reduce operating costs by cutting energy purchases from the grid to negligible levels. And – if the microgrid is equipped with “smart” interconnection equipment like inverters that can sell energy onto the grid when the price is high and use batteries to store it when the price is low – it can even generate income. Of course, it requires up-front capital to finance purchases of solar panels and the like, but payback periods can be as short as one year.

Other benefits include a reduced carbon footprint (assuming the generation source is renewable), diversification of energy sources, and improved power quality. But, in light of a world vulnerable to cyber attacks that wreck havoc on the grid, perhaps the most important benefit is improved security and reliability that comes from a microgrid’s ability to operate autonomously from the larger “macro” grid. If the larger grid is shut down by a cyber attack, a microgrid can continue operating undisrupted. And a cyber-terrorist’s ability to paralyze an entire economy via an attack on the grid is at least slightly reduced when that attack fails to reach those operating on their own autonomous grids.

Indeed, prominent thinkers in other fields have emphasized the security benefits of moving away from a centralized distribution system to an increasingly de-centralized and autonomous one. One excellent example of this push is Nassim Nicholas Taleb’s famous book The Black Swan: The Impact of the Highly Improbable. Taleb believes that unforeseen and highly improbable events are more difficult to predict than we commonly believe. So instead of just trying to predict and prevent them, we need to consider how to minimize the negative impact of such events when they occur. One way to minimize their impact is to build redundancies into a system. A microgrid that can operate autonomously from the larger grid is one way of building a more redundant and robust system. This is why the United States Department of Defense is a major proponent of microgrids, developing microgrids for military bases and improving its security of energy supplies and sources.