Monday, 13 July 2009
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.