Grid-Tie-Inverter-G83-Certification

What is a Grid-Tie Inverter?

A Grid-Tie inverter converts DC (Direct Current) from renewable energy sources such as Solar PV and Wind Turbines into 230 VAC (Volts Alternating Current). What is clever about a Grid-Tie inverter is that it synchronizes with the national grid's electricity supply frequency and back feeds the grid. This pushes electrical current back into the national grid and if the power your inverter is supplying is in excess of the power you are consuming then it will effectively run your electric meter backwards.

The clever part of a Grid-Tie inverter is that if the national grid supply is shut off then the inverter instantly senses this and ceases to create power. If this did not happen then the grid would still be energised by your Grid-Tie inverter (Extremely dangerous to a linesman / electrician working on a supposedly dead grid!)

In the UK a Grid-Tie inverter has to have a G83 Certificate to allow it to interconnect to the national grid system.

With recent advances in technology a Grid-Tie inverter can be purchased for around £100 GBP for a 200W version which will allow you to reduce your electricity bills. They can be added in parallel over time to allow for expansion. You can use them with many sources of renewable energy, some examples are: A Wind Turbine, Solar Panels, Micro-Hydro Turbines or even a Diesel Generator running on WVO (Waste Vegetable Oil)

The ever popular Windsave house mounted wind turbine uses the same setup described above to back feed the national grid system.

Domestic-Wind-Turbines

There are 2 main types of wind turbine that are suitable for use with a domestic house.

1. Grid-Tied Wind Turbine:

Grid-Tied, simply put, means your wind turbine is connected in line with your national grid electricity supply. When you are using less electricity than your wind turbine is producing then the excess power is pushed past your electricity meter and back into the nation grid. This enables your meter to run backwards and reduce your bill you have to pay to your electricity supplier.
The disadvantage with a grid tied wind turbine is that in the event of your electricity supply shutting down (Power Cut) then the wind turbine supply shuts down also meaning you will have no electricity supply until the grid supply is restored. This is a safety feature to prevent your supply back feeding the national grid in the event of a power cut.

2. Isolated Wind Turbine Feeding Batteries:

A system that supplies batteries is not as efficient as a grid tied wind turbine due to the losses in storing electricity in batteries instead of directly feeding the national grid but the plus side is that the electricity you produce can be stored for later use.
You require a wind turbine designed to charge your battery bank. You also require suitable, maintenance free batteries for power storage, if you require domestic AC (Alternating Current) power then you will need an inverter to convert the DC (Direct Current) back to 230V AC that can be used with mains powered domestic appliances.