Battery energy storage economic calculation method

How do you calculate battery efficiency?

Efficiency is the sum of energy discharged from the battery divided by sum of energy charged into the battery (i.e., kWh in/kWh out). This must be summed over a time duration of many cycles so that initial and final states of charge become less important in the calculation of the value.

How is energy storage rated capacity calculated?

The rated capacity of the energy storage system is calculated as the average discharge power output over a two-hour period. For storage projects coupled with generation technologies such as PV, the rated capacity of the storage cannot be larger than the rated capacity of the PV system.

What has made battery energy storage systems more cost-effective?

The recent advances in battery technology and reductions in battery costs have brought battery energy storage systems (BESS) to the point of becoming increasingly cost-effective.

Can a battery lifetime analysis and simulation tool improve demand charge management?

A previous study used the Battery Lifetime Analysis and Simulation Tool (BLAST) developed at the National Renewable Energy Laboratory (NREL) to consider optimizing the size and operation of an energy storage system providing demand charge management. Battery degradation and capital replacement costs were not considered.

What is the maximum energy accumulated in a battery?

The maximum amount of energy accumulated in the battery within the analysis period is the Demonstrated Capacity (kWh or MWh of storage exercised). In order to normalize and interpret results, Efficiency can be compared to rated efficiency and Demonstrated Capacity can be divided by rated capacity for a normalized Capacity Ratio.

What is solar energy storage (Sam)?

SAM links a high temporal resolution PV-coupled battery energy storage performance model to detailed financial models to predict the economic benefit of a system. The battery energy storage models provide the ability to model lithium-ion or lead-acid systems over the lifetime of a system to capture the variable nature of battery replacements.