The balance of system (BoS) components are highly significant in the total cost of battery storage systems, often constituting a substantial portion of the overall investment.
Significance of Balance of System Components in Battery Storage Costs
- BoS components typically include battery management systems, cooling systems, electrical wiring and cabling, inverters, transformers, structural supports, and other necessary hardware beyond the battery cells themselves.
- The cost share of BoS components can range markedly depending on the system scale and specific design, but commonly accounts for 20% to 40% of the total battery energy storage system (BESS) cost. For example, for a 50 MW battery storage system, BoS costs can be between 20% to 30% of the total system cost, equating to $1 million to $3 million in some cases.
- In practical terms, studies show:
- BoS costs can add about $50 to $150 per kilowatt-hour (kWh) or per kilowatt (kW) to the system, contributing significantly alongside battery cell costs which historically have been the largest single expense.
- In some analyses, BoS can represent one-half to three-fourths of the installation’s total cost, particularly when battery duration is short (e.g., half-hour), since the battery capacity cost is lower but support infrastructure remains necessary.
- The importance of BoS components is expected to grow as battery prices continue to decline. With battery costs falling dramatically over the last decade, BoS costs now represent a larger relative share of the total system cost, highlighting the need for cost reductions in these components to continue making storage projects economically feasible.
Summary
| Component | Typical Share of Total System Cost |
|---|---|
| Battery Cells | Largest single expense, but declining |
| Balance of System (BoS) | 20% to 40%, sometimes up to 50–75% depending on battery duration and system design |
| Installation & Others | Additional 5% to 20%, varies by project |
In conclusion, balance of system components are a critical and significant part of the total cost structure of battery storage systems. With battery prices dropping, reducing BoS costs will be key to improving the economics of future battery storage deployments.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/how-significant-are-the-balance-of-system-components-in-the-total-cost-of-battery-storage-systems/
