Energy is the lifeblood of military installations. Just as the Armed Forces rely on petroleum to drive ships, fly aircraft, and support troops in combat zones, they depend on electricity to power fixed installations. The military’s use of installation energy entails risks as well as costs. Installations are dependent on a commercial grid that is vulnerable to disruption due to aging infrastructure, severe weather, and physical- and cyber-attacks. There is growing concern whether military bases can maintain critical functions during outages that last for days or weeks, as opposed to hours.
DoD is actively pursuing the deployment of microgrid technologies to provide improved energy security for longer durations. DoD also has been working with the private sector to develop renewable generation assets on military installations. Most of the sources of renewable energy (commonly solar and wind) are intermittent. Although of value to improving energy security in some circumstances, they cannot be relied on as a backbone of an energy security solution in the absence of energy storage. Given DoD’s energy security requirements, its plans to deploy microgrids, and its existing and planned deployment of renewables, the potential to use energy storage to provide a better and more cost-effective energy security solution is significant.
ESTCP’s FY19 solicitation topic, Large Scale Energy Storage and Microgrids, directly tackles this opportunity. Integrated into a microgrid, energy storage can play a key role in DoD mission assurance by providing increased reliability for lower costs. Some of its benefits include:
- Minimal to zero wasted energy generated from the renewable sources as the energy is either stored for future use for events such as grid outage or is fed back to the utility grid.
- Seamless transition between alternative generation sources (e.g., solar to wind on a cloudy day) to provide a continuous source of energy.
- Savings obtained through reduction in demand charges by peak load shaving.
- Revenue generated through participation in utility ancillary service programs by selling excess energy to the grid.
The objective of the ESTCP solicitation is to demonstrate and validate the energy security and economic value of integrating large scale energy storage into current and future microgrids at military installations. Storage performance will be measured in terms of the following six key attributes:
- Coverage: kWs of backup power provided
- Availability: number of hours per year for which coverage is available
- Reliability: Level of independent back-ups for reliability (N+1, N+2...)
- Duration: The number of consecutive hours that coverage can be maintained
- Ride-through capability: The fraction of load for which uninterrupted power with appropriate power quality can be provided
- Stacked-value: The combination of revenue and savings and any avoided costs associated with the capital and operations cost of the microgrid.
Projects will be executed in two phases. Phase 1 is the design and modeling to assess system’s technical and financial outcomes. Each project will assess five installations out of seven designated installations - Naval Air Station Corpus Christi (TX), Naval Air Station Patuxent River (MD), Naval Base Ventura County (CA), March ARB (CA), Westover ARB (MA), Holloman AFB (NM) and Fort Bliss (TX/NM). The performance at these installations will provide DoD with an understanding of where and why storage can contribute effectively to an energy security solution. Phase 2 will include demonstration and validation of the technology at the selected installations to reduce risks for future deployments.
For each of the installations selected for Phase 1, installation-specific data such as loads, PV, utility rates, number of and size of Gensets & UPS, Fuel Tank and Fuel Price will be provided by ESTCP to allow for realistic modeling and consistency in modeling among proposers selected for award. In addition, market-specific data will be provided for electricity markets in which participation by energy storage and diesel generation assets is deemed available. ESTCP selected several projects with a wide array of promising storage solutions. Solutions included Li-Ion battery, Flow battery, Ultr-Cap, ZnMnO2, pressurized air, to mention a few. In addition to comparing these solutions to the baseline microgrid, the battery storage solutions will also be compared against one another to determine the performance and economic value.
Energy security performance will be assessed by comparing the critical load protection from a baseline microgrid dependent on diesel generators only at each selected installation with the proposer’s diesel, renewable and storage microgrids. In addition, energy security performance will also be assessed for two alternative scenarios. These alternative scenarios are intended to provide additional understanding of the performance of the proposed systems under different operating conditions.
- The first alternative scenario involves critical loads exceeding expectation by 30%.
- The second alternative scenario is an extended duration for which fuel is no longer available (the baseline diesel only microgrid has no capability to provide power in this case).
Based on Phase 1 modeling results, a subset of Phase 1 projects will be selected for Phase 2 for demonstration and validation of the technology. Phase I work will begin in Fall 2018 and be completed by March 2019. Phase II proposals will be requested in the spring of 2019. The Final Reports for each of the Phase 1 projects will be posted on the ESTCP website at www.serdp-estcp.org at the end of the Phase 1.