4.3.18.16. Operational Energy
4.3.18.16. Operational Energy
Emerging threats to the logistic resupply of operational forces, the trend toward ever greater energy demand in the operational forces, and increasing costs to operate and resupply energy-intensive systems have all put increasing focus on lowering system and unit energy demand. Reducing the force’s dependence on energy logistics can improve the force’s mobility and resilience and increase its control over the timing and conditions of the fight. Focusing on energy as an explicit design consideration and systems engineering (SE) category is a significant change in practice and thinking, to help manage emerging operational challenges.
The Program Manager and Systems Engineer can help lower operational energy by addressing issues associated with the system’s energy logistics support and power resupply frequency.
This approach should generate informed choices based on the threshold and objective values of the Energy Key Performance Parameter (KPP) for the system. For liquid energy-consuming systems, the top-level units of measure for the Energy KPP might be gallons of fuel demanded (consumed) over a defined set of duty cycles, or to accomplish a specified mission goal such as a sortie. These measures may be further decomposed into weight, range, electric power demand, and other relevant measures to inform the necessary SE trade analysis. The intended result is a comprehensive set of trade-space choices for industry to consider to deliver solutions that are not only energy efficient but also mission effective and affordable. See Joint Capabilities Integration and Development System (JCIDS) Manual (requires Common Access Card (CAC) to access website) and CJCSI 3170.01H linked at the end of this section.
Energy’s relationship to performance arises from the operational context in which the system is used. Accordingly, the scenarios that illustrate how the system is used, as part of a unit of maneuver, are essential to understanding the energy supply and demand constraints to be managed. This is essentially the same approach as balancing survivability goals against lethality goals in the engineering trade space. Operational energy issues include:
- How the system and combat unit refuel/recharge in the battle space scenarios, and how often
- How this refueling/recharging requirement might constrain our forces (limit their freedom of action, on-station time, signature, etc.)
- How the adversary depicted in the defining scenarios might delay, disrupt, and/or defeat our forces by interdicting this system’s refueling/recharging logistics
- How much force protection could be diverted from combat missions to protecting these refueling/recharging events when and where required
Systems Engineers should consider incorporating energy demand in design, technology, materials, and related issues into the system trade space along with other performance issues, so that oppressive energy resupply needs are not inadvertently introduced in the attempt to achieve other performance goals (e.g., survivability, lethality). In practice, this means requirement developers should factor into the system design the necessity of refueling/recharging using the same scenarios that are used to illustrate other performance requirements, and allowing the adversary a realistic chance to interdict the refueling/recharging effort. Systems Engineers may find it necessary to have a continuing dialogue with the warfighter (the user and requirements developer) to help grasp the operational impact of these issues and depict them in trade space decisions.
Energy-related engineering analysis should begin early enough to support initial Analysis of Alternatives (AoA) planning following the Materiel Development Decision, and should also be routinely updated to inform any AoA performed later in the life cycle (i.e., in support of block upgrades and modifications).
The following documents provide the Program Manager and Systems Engineer with additional insight into the issue of Operational Energy in the acquisition life cycle:
NOTE: The results of the sustainability analysis (see DAG section 4.3.19.2. Sustainability Analysis) can be used to inform energy analyses.
DAG Tutorial 
