As extreme weather incidents become more frequent, surprise power outages from a central utility will rise in tandem. Such power outages are an inconvenience that can be disastrously expensive due to lost productivity and labor but also ancillary costs such as spoilage, and cleaning. Beyond loss of production and restarting costs, resiliency needs apply to certain industries, such as healthcare and data centers, as central concerns. Their entire business relies on consistent, reliable power.
Renewables can play a key role in resiliency during such events and offer an alternative to relying on a single source of power. In the absence of service from a centralized utility, distributed energy sources (DERs) can be islanded from the grid and act as a mini utility for a specific site. So, in order to ensure a consistent supply of energy to a residence or facility, decentralized, local generation may be required.
This sheer number of outages can be overwhelming and continues to grow. According to the Energy Information Administration, most power outages to the bulk electric system between 1992 and 2012 were due to severe weather events. A 2013 report by the Department of Energy¹ estimated that severe weather-related outages cost companies between $18 and $33 billion per year. With record-breaking storms happening more often, that number easily doubles to between $40 and $75 billion per year. Multiple states had power outages that exceeded thousands between 2008 and 2017.
Many businesses install diesel generators as a back-up power source to satisfy critical loads and avoid costly shutdowns during weather-related blackouts. However, doing so comes with its own set of challenges. First, they must install enough capacity to meet their maximum critical loads which is a capital expenditure that sits idle for most of the year. Renewables can help minimize this expenditure and provide other value, but they are not a silver bullet. Renewable generation like solar and wind are unreliable since they depend on changing weather conditions. One way of overcoming this limitation is to pair renewable generation resources with storage to enable charging from excess generation and discharging when the renewable generation dips or even totally disappears.
Renewables have the added benefit of being available during non-outage periods to satisfy portions of the facility’s load and help save on utility expenditures, which is a capability not available with diesel generators. Generator exhaust contains contaminants² so their use is increasingly regulated unlike the clean energy from renewables. For many facilities, trying to build a purely renewable system that provides full ride through extended outages requires significantly oversized batteries or excessive solar deployments.
The problems of requiring oversized renewable and storage resources or excessive generator runtime can be solved by combining the two approaches. Pairing a reasonably-sized renewable microgrid used to offset utility costs with a backup generator to provide extra security during extended outages is both economical and safe. The key is determining the right balance between renewable generation, storage, and traditional generation capacities. Renewables offer an attractive addition to diesel generators when resiliency and critical load support is a primary concern. In addition, they can help offset the expense of not only installing a distributed system for utility back-up purposes but also eliminating the costs of unexpected outages.
As with any microgrid, sizing is only one part of the equation. Once the microgrid is installed, it must be operated in a way that optimizes its value. When pairing renewables with diesel generation capacity, that value exists across a wide spectrum from critical load support to overall utility savings and return on investment. This requires locally advanced controls to enable the DERs to behave in an optimal way outside of outages under changing energy generation. This accounts for generation from the solar assets or fluctuating load as well as updates in the utility rate structures and incentive program rules.
Control algorithms run the gamut from simple set-and-forget to those like CleanSpark’s M400 controller, which uses patented forecasting techniques and advanced local intelligence to dynamically modify DER interaction due to changing weather, site and utility conditions. CleanSpark’s mVSO product can optimally size resources by using advanced modeling from an extensive equipment library. During these modeling exercises, the cost of outages and the understanding of a facility’s critical loads are key factors in determining the right combination of resources to balance load safety and economics.
With the continued frequency of outages and possibility of even larger grid failures like the recent snowstorm in Texas, it’s imperative to begin exploring renewables and other sources of power. CleanSpark’s intelligent controls and user-friendly offerings helps ease anyone into the start of their journey with renewables. Don’t wait until it’s too late – step into the world of microgrids before you’re stepping into another dark room.