Uninterruptable Power

People often think, wrongly, that having solar panels, especially with batteries, means that you will have power if there is a power cut. This is NOT the case for most SolarPV setups. In the UK, unlike somewhere like South Africa, power outages are rare and it is not necessary to go to the extra complexity and expense of installing Uninteruptible Power.

The SolarPV system can be added to the wiring of the house with the minimum of alteration if the SolarPV system injects its power between the electricity meter and the consumer unit (what old timers like me call "the fuse box"). This arrangement also allows extra energy to be fed back into the grid network if desired. However, if the external power is cut the SolarPV system MUST (for safelty reasons) stop supplying power. If Uninteruptible Power is required extra measures are needed; either a system to disconnect the house wiring from the grid or a system to connect essential loads in the house to a separate output on the inverter. We went for the latter.

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