From flashlights to uninterrupted power supplies, energy storage assets have a long history of supporting critical infrastructure and services during times of natural disaster. By providing power and lighting during large-scale weather events such as Superstorm Sandy and Hurricanes Irene and Katrina, energy storage systems of all shapes and sizes reduce the time it takes for first responders to begin recovery efforts. Unfortunately, while extremely valuable when needed, most energy storage assets remain idle for long periods of time and are viewed as “sunk” costs without the ability to generate revenue. Furthermore, many energy storage systems require mandatory and ongoing maintenance procedures, which if not completed properly, put the entire performance of the systems at risk.
Today, emerging technologies in the energy storage field are changing this paradigm. Rather than representing fixed costs, energy storage systems are transforming into active assets that can be used to create sustainable revenue streams. Whether through participation in new energy markets recently opened by the Federal Energy Regulatory Commission (FERC), or through their inherent ability to extend life-cycling capabilities, these new energy storage systems are poised to lower operating costs by reducing peak demand charges, increase onsite power generation efficiency, and extend emergency generator run-times. It’s a new approach that enables energy storage—once a costly, passive (but necessary) disaster recovery asset—to emerge as a cost-effective, active participant that stands to make power systems and consumer services more resilient, more efficient, and more responsive to the need for a sustainable, readily-adaptable energy environment.
One such example of an emerging energy storage technology is the recent introduction of sodium-nickel-based batteries to the marketplace. With 4,500 full depth of discharge cycles, multi-layered safety features—including the core chemistry, triple-encased steel packaging, and redundant controls with remote diagnostic capabilities—these batteries enable end users to reduce daily operational costs and, when the next disaster strikes, provide an additional level of resiliency to the electrical grid or host facility.
This type of battery design is a clear departure from traditional battery technologies. Using a sodium-nickel-based chemistry, the cells inside the battery operate at elevated temperatures. These elevated temperatures help immunize the battery from extremes in the ambient temperature environment. The battery package surrounding the cells contains a highly-effective thermal insulation which minimizes thermal power losses and improves safe operation across a broad range of applications. The battery’s long life originates in its solid electrolyte which experiences negligible degradation over battery service life, even at deep discharges and high cycle volumes. When fully-integrated into existing power infrastructure or used in grid modernization efforts, this battery technology can have a major impact on how well an area manages a catastrophic event, simultaneously providing a means of controlling costs during day-to-day operations.
Emerging Markets for Energy Storage
New energy storage system designs offer safer and longer operational lifespans, as well as allow customers to install large battery systems that provide emergency power to critical functions when the electrical grid fails. Equally important is their capacity to produce revenue and reduce costs during normal operation. Recent FERC orders have enabled battery systems to participate in the wholesale energy markets and perform such actions as frequency regulation, energy arbitrage, and even demand response functions. NYISO 1 and PJM 2 have enabled energy resources to participate in their energy markets, and multiple battery installations are creating revenue that supports these installations. Additional examples of this new approach are outlined below.
Utilities are continuing to exploit new battery technology’s enhanced safety and lifespan capabilities by installing batteries at substations and in community energy storage systems. Battery systems help to provide efficient use of utility resources by extending their peak demand capabilities. In addition, during periods of grid stress, these energy storage stations can provide either the substation or the larger community with valuable extended operating power to allow end users to charge their communications equipment or even their vehicles.
Behind the Meter Applications
Retail customers, including large pharmaceuticals, manufacturing plants, and office complexes, are turning to energy storage systems as a cleaner, more cost effective way to manage their peak demand and peak energy charges. In the event of a power outage, these systems are designed to operate as an uninterrupted power supply, and provide seamless power to critical infrastructure. For example, since the earthquake and tsunami disaster in March 2011, Japan has been a major proponent of this approach.3 Energy storage deployment between utilities and homes has emerged as a key component of their recovery and rebuilding effort.
Combined Heat and Power and Microgrids
Another means of leveraging the value of active energy storage systems is to integrate them with other onsite power systems. The integration of batteries with a combined heat and power system, for instance, has the potential to create a safe, resilient, and efficient energy campus microgrid. In this scenario, natural gas-powered engines provide the facility’s base electrical needs. Additionally, by leveraging the engine’s high-temperature exhaust, it meets the facility’s heating and cooling needs. The battery charges when the electrical load is low and discharges when the facility’s load exceeds that of the engine’s capabilities, thereby providing the much needed additional power capacity for the microgrid. During outages, the battery system is configured to work alongside the generator backup system to optimize generator runtime and increase fuel efficiency.
Backup Power—Diesel Fuel Use Reduction
In remote grid telecom applications, advanced technology battery systems have already proven their ability to nearly double the efficiency of the diesel generators they support.4 This reduction in fuel use has a positive impact on the user’s operating costs, but also serves to reduce fossil fuel consumption overall. During extended outages or natural disasters, the supply of diesel fuel can become severely limited. Although cell towers and data centers support many critical communications services, they aren’t alone in needing priority access to fuel. Other consumer services can be impacted as well. When New York University’s Langone Medical Center experienced backup generator failure during Superstorm Sandy5, it prompted a mass evacuation of patients from the facility. An energy storage system could not only provide backup power support to a health or emergency facility, but it could also reduce an existing generator’s diesel fuel usage as a whole, extending services to those who need it most.
Energy Storage Vision for Rebuilding
Deploying energy storage below the grid will increase grid resiliency, promote greater efficiency and more sustainable energy generation. By increasing the amount of energy storage nationwide, the ability to incorporate larger penetrations of sustainable, but variable, energy sources would be enhanced.
By deploying correctly-sized energy storage at power plants, black-start capabilities will become more widely available for use as needed. On an ongoing basis, these energy storage systems will be able to increase revenue by participating in ancillary services or energy markets.
System deployment at substations can provide required overload support when the equipment is aging or if there is substantial load growth due to unexpected increased demand. Energy storage systems could also provide daily voltage and ancillary services support, thereby providing a solid revenue stream.
Critical infrastructure such as police command centers, fire stations, cell towers, and hospitals often have diesel generation as backup power. By deploying energy storage systems at these facilities, the diesel system can be optimized to decrease generator runtime. New energy storage battery technology deployed at remote communication stations has already proven that the runtime capability of a single unit of fuel can be raised by almost a factor of two when the battery is continuously paired with a diesel engine. The energy storage component can then also be used on a daily basis to reduce the facility’s total energy bill by reducing energy purchases during peak times, and reducing energy and demand charges.
In addition, designated community, communication, cooling, or heating centers located on campuses, convention centers, or other public facilities can be enhanced by updating infrastructure and incorporating energy storage systems to provide support during outages. These facilities can also leverage energy storage to reduce their energy costs by leveling peak demand and peak energy charges.
Energy storage has traditionally been viewed as an expensive “must-have” for disaster recovery efforts. While recent events support the importance of grid modernization through energy storage systems—the idea that these systems could be used to generate revenue streams and reduce operating costs is a newer concept. Emerging battery technologies, however, prove that energy storage can simultaneously and safely create ongoing value and provide support in times of crisis.
1 New York Independent System Operator
2 A regional transmission organization
3 Energy Storage: Asian Systems and Apps. Smart Grid Insights, August 2012 (www.smartgridresearch.org)
4 Sodium-Metal Halide Batteries in Diesel-Battery Hybrid Telecom Applications. General Electric Company, 2011 (geenergystorage.com)
5 Diesel: The Lifeblood of the Recovery Effort. Data Center Knowledge, 2012 (www.datacenterknowledge.com)
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