Optimizing PV Systems January 2015 - Part 2: Energy Storage | Page 20

Battery Racks and Enclosures

With any energy storage solution, lead-acid or lithium-ion, how the battery is physically installed is equally as important as selecting the correct technology for use. There are several variables that must be considered. Some items to consider, but not limited to, include:

• Type of battery? – The kind of technology used can limit how the battery is placed physically. For example, Lithium-Ion battery packs can be server-rack mounted, whereas a flooded lead-acid would traditionally use a 1-2 tier metal rack indoor solution

• Indoor or Outdoor Installation? – This will determine what, if any, weatherproofing is required. Most outdoor applications for VRLA and Lithium Ion solutions require NEMA 3R rainproof enclosures to prevent the elements of nature destroying batteries. Whereas, indoor applications require simpler standards to be honored.

• Rack or Enclosure Material? – Aluminum or steel is always recommended as it represents the strongest and highest durability of any battery rack/enclosure solution. Wood or plastics are not recommended as these can be compromised by weight and fire considerations

• Ventilation? – Very important as this is always required with flooded lead-acid and VRLA batteries to prevent hydrogen gas build-up with indoor applications.

• Spill Containment? – Always required with flooded lead-acid and in some VRLA applications as acid is present in these batteries.

OPTIMIZING PV SYSTEMS - PART 2: ENERGY STORAGE

• Seismic Considerations? – If there is potential for any seismic event, the need for meeting building codes for installation to prevent damage is always required.

With any battery rack or enclosure, please ensure all proper safety, installation, and maintenance guidelines are followed by referring to the appropriate battery or rack/enclosure manufacturer user manual prior to any work beginning. Furthermore, please refer to any local residential/commercial building code requirements when installing batteries + racks and enclosures.

Safely Installing and Sizing Batteries for Power Conversion Systems

Battery based power conversion systems utilizing renewable energy require proper electrical sizing for the building site and power application for which it has been designed. Site locations vary from residential garage or outbuilding to commercial building utility vaults and basements. Electrical load profiles also have significant variability in addition to the site’s power application; be it backup power, self-consumption, sell-back to the grid, or other storage based strategies that can be used to lower utility bills.