NABCEP Battery Storage Systems & Energy Storage 3

Question 1

What is the typical usable capacity percentage for a lithium iron phosphate (LFP) battery relative to its nameplate capacity?

Accepted Answer

90–100%

Answer

50–60%

Answer

70–80%

Answer

100–110%

Question 2

IEEE 1547 is directly relevant to battery storage systems connected to the utility grid because it governs:

Accepted Answer

Distributed energy resource interconnection requirements

Answer

Battery cell manufacturing tolerances

Answer

Electrical conduit fill calculations

Answer

Solar irradiance measurement protocols

Question 3

A battery storage system is rated at 10 kWh with a round-trip efficiency of 92%. How much energy must be put into the battery to retrieve 9.2 kWh?

Accepted Answer

10 kWh

Answer

8.46 kWh

Answer

9.2 kWh

Answer

10.87 kWh

Question 4

Which interconnection mode allows a battery storage system to operate in isolation from the grid to serve local loads during a utility outage?

Accepted Answer

Island mode (off-grid mode)

Answer

Grid-following mode

Answer

Anti-islanding mode

Answer

Reactive power compensation mode

Question 5

Per NFPA 855, what is the maximum allowable energy capacity for a single lithium-ion battery storage unit installed in a residential occupancy without requiring additional separation or suppression?

Accepted Answer

20 kWh

Answer

10 kWh

Answer

40 kWh

Answer

80 kWh

Question 6

In a battery storage installation, what is the purpose of the 'low-voltage disconnect' (LVD) function?

Accepted Answer

Prevent the battery from discharging below a damaging voltage level

Answer

Disconnect the PV array during high irradiance periods

Answer

Limit the maximum charge current from the solar array

Answer

Isolate the battery from AC loads during grid-parallel operation

Question 7

When performing a battery storage system commissioning check, which parameter is most important to verify before energizing the system?

Accepted Answer

Correct polarity of all DC wiring connections

Answer

The color of the battery enclosure

Answer

The brand of the solar monitoring software

Answer

The number of AC circuits in the main panel