Requirements for your battery energy storage system
By Brendan D. Miller, P.E.
The scale of batteries serving today's U.S. power grid are projected to increase, which isn't a surprise considering the commonality of solar projects coupled with Battery Energy Storage Systems (BESS). With energy storage growing as a critical asset to the grid, it's important to review these three common BESS requirements to help avoid unexpected costs or schedule delays.
Drainage and Stormwater Control Requirements
To protect the soil, land, and surrounding communities during a BESS project, drainage and stormwater requirements are put in place to control water leaving the site, which limits environmental disruptions and flooding.
During the construction stage, native soil is disturbed and moved to build a reliable BESS facility. In urban areas, if proper planning and control is not prepared into the design, this can leave downstream communities at risk of increased sediment and stormwater runoff. In the post-construction stage, after the soil is stabilized, there is typically an increase in impervious areas. This leaves less soil for infiltration and adds a need for a long-term stormwater plan. Systems in more urban environments come with additional requirements, including specific tie-in agreements to existing storm drains, location-specific discharge requirements, and downstream system upgrades. Since these systems rely on gravity to move water, this can sometimes leave very little design flexibility. Missing these requirements early can result in major redesigns to accommodate the placement of storm drain infrastructure down the road.
Equipment Layout Requirements
Developers must anticipate the requirements for land use before determining the BESS equipment layout in the initial design process. These considerations include leaving room for landscape and setback buffers, drainage infrastructure, interconnection equipment, and access roads for semi-trailers and cranes. The remaining land is then ready for the most important step of the project—designing the areas to install the batteries and associated electrical equipment.
The best BESS site design finds the right balance between a compact layout and open access. More compact sites can lower the overall cost of the project by shortening the length of underground wires and cables, and by reducing construction needs for earthwork. However, compact layouts can also limit access and lead to inefficient production for contractors and complicated maintenance. Additionally, the design must foresee the use of large wires that need to be spaced apart from each other to prevent overheating during operations. Ultimately, the layout and cable management must be considered during the early stages of a conceptual design to help find the right balance.
Fire Code Requirements
There is another major equipment layout requirement that cannot be forgotten: fire codes. Fire is a risk for all energy projects. At the layout stage, this typically means providing sufficient access to the site or a defensible perimeter inside and/or outside the fence. Missing this important step can once again lead to a complete redesign of a site.
Another important factor in meeting the fire code is through water access. Trucking in water for construction work may be a feasible option, but many fire officials will require a nearby source of water for fighting fires, both during construction and operations. With sites in urban areas, the solution could be getting a fire hydrant added to the site by the local municipality. If the equipment itself is sprinklered, a hookup for the sprinkler system may be required. At the other end, if the location of the BESS site is more rural, a tank or a water well and the associated power and equipment to operate it may be required.
Optimizing the planning stage
Although each project has unique considerations at the start of the development and construction cycles, it is best practice to plan for drainage, equipment layout, fire codes, and basic utility access. While rural areas have more design flexibility, there tends to be limited access to basic utilities and further distance to interconnect. Conversely, as you move closer to urban areas and more resources, you are met with less land access and more requirements to keep the site and surrounding communities safe.
In the evolving world of renewables and power delivery, additional requirements may be needed by developers, contractors, and owners during the development, design, and construction phases of BESS sites.
Brendan D. Miller, P.E., is Energy Storage Lead Engineer, Westwood Professional Service (www.westwoodps.com). Brendan has 20 years of experience serving a wide variety of markets including solar energy, power delivery, wind energy, residential, commercial, and industrial development projects. Currently, Brendan co-leads the energy storage service team with a specialized focus on development, layout, and civil design.