DC or AC Coupled Battery?

Direct Current
Alternating Current
DC Coupled or AC Coupled

1. Efficiency

DC vs AC Coupled Battery - Conversions Efficiency

2. Wastage

DC vs AC Coupled Battery - No Wastage

3. National Grid Approval

DC vs AC Coupled Battery - DNO Approval

4. Power Output

DC vs AC Coupled Battery - Power Output

5. Other

DC vs AC Coupled Battery - Other

6. Important difference if installing backup

For some AC coupled systems, if there is a power cut the solar system will stop producing energy – only the battery will provide power until it is empty.  A DC Coupled Hybrid solution will allow the solar to continue working in backup mode.

7. Resilience

Having a separate solar inverter and AC battery charger/controller may be beneficial in the future.  Solar inverters tend to last 8-10 years but are easily and cheaply replaced.  Having a one box solution for battery, solar inverter, battery charger controller, like Tesla, may be expensive or impossible to repair after the warranty expires compared to a very modular system.