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Utility reliability requirements are set by PUCs and Federal Regulators. Unless the neighborhood microgrid is always islanded from the grid, there are quite a f

by el_g 13y ago

Utility reliability requirements are set by PUCs and Federal Regulators. Unless the neighborhood microgrid is always islanded from the grid, there are quite a few problems to solve: 1) Who will respond to outages and make repairs. This includes issuing clearances to crews making repairs. 2) Who will issue protection settings (reclosers/relay settingsfuse coordination, etc) and perform fault analysis? 3) Unless you have generators then they'll need to provide power when your PV systems don't meet demand 4) Someone needs to investigate power quality problems 5) Generation dispatch to meet demand and maintain a system frequency of 60Hz. 6) Someone must handle interconnection requests. Who is going to stop your neighbor with a 50Hz generator that can handle 50% of your microgrid load from connecting to the system, causing a big frequency drop and damaging appliances? Your microgrid doesn't have enough inertia to absorb something something like that. 7) Are the micro grid operators subject to the same reliability requirements as utilities? 8) Are you going to install your own poles and wires? That includes permitting, responding to joint use requests per regulatory requirements, etc.

brownbat 13y ago
Some of these issues are created by the bulk power system model. For example, heavy industry and long distance transmission require much more precise balancing than neighborhoods. Others can be financed in the same way that HOAs finance capital improvements, or the same way tenants of an apartment benefit from the use of a building and maintenance crew they could never afford to build or have on retainer individually. Others would be obvious how to resolve in practice (ie, How do you prevent your neighbor from wrecking the system? Well, how do you currently prevent your neighbor from hooking up his pipes to the neighborhood fire hydrant? A combination of common sense regulations and social mores.) If our default position were microgrids, we might wonder of a unified system, "but how would you prevent cascading blackouts?" The current answer is you don't, major cascades just happen around once a decade. It's all a series of tradeoffs, and I agree with you, usually the tradeoffs favor bulk generation. The balance shifts when monopolies abuse the public trust. So here, things like load balancing are an interesting example, since that's not an area where HECO has always excelled. UCSD is using a microgrid because they can't achieve sufficient reliability from California's bulk power system: http://www.bloomberg.com/news/2013-10-17/ebay-to-ellison-embrace-microgrids-in-threat-to-utilities.html http://www.bloomberg.com/news/2013-10-17/ebay-to-ellison-emb...

by el_g 13y ago

brownbat 13y ago

Some of these issues are created by the bulk power system model. For example, heavy industry and long distance transmission require much more precise balancing than neighborhoods. Others can be financed in the same way that HOAs finance capital improvements, or the same way tenants of an apartment benefit from the use of a building and maintenance crew they could never afford to build or have on retainer individually. Others would be obvious how to resolve in practice (ie, How do you prevent your neighbor from wrecking the system? Well, how do you currently prevent your neighbor from hooking up his pipes to the neighborhood fire hydrant? A combination of common sense regulations and social mores.) If our default position were microgrids, we might wonder of a unified system, "but how would you prevent cascading blackouts?" The current answer is you don't, major cascades just happen around once a decade. It's all a series of tradeoffs, and I agree with you, usually the tradeoffs favor bulk generation. The balance shifts when monopolies abuse the public trust. So here, things like load balancing are an interesting example, since that's not an area where HECO has always excelled. UCSD is using a microgrid because they can't achieve sufficient reliability from California's bulk power system: http://www.bloomberg.com/news/2013-10-17/ebay-to-ellison-embrace-microgrids-in-threat-to-utilities.html http://www.bloomberg.com/news/2013-10-17/ebay-to-ellison-emb...