what is microgeneration ?

What is microgeneration?

Around the world the definition of microgeneration can vary. Microgeneration is classified by ESB Networks as grid connected electricity generation up to a maximum rating of 11kW when connected to the three phase grid (400V). The vast majority of domestic and agricultural customers are connected at single phase (230V) and for these customers to be classified as microgenerators the maximum rating permitted is 6kW. These ratings are in line with Irish conditions prescribed in European standard EN50438.

In Ireland customers with microgenerators can avail of a stream lined, one page connection process (using form NC6)  Customers who exceed the classification must engage in a more demanding application and connection process. However ESB Networks intend to make the connection process for units up to 50kW less onerous than the process required for larger generators.

A microgenerator may use any one of the following technologies to generate electricity:

• Wind turbine
• Photovoltaic panels (also known as solar electric panels)
• Micro-hydro (scaled down version of hydro-electricity station)
• Micro-CHP (fuelled by bio or fossil fuels)

Two or more of the technologies may be combined to create a hybrid system. Domestic and small commercial wind microgeneration involves using a small-scale wind turbine system to harness energy from the wind. In general it is at its most competitive and cost effective in remote, exposed areas or for charging batteries on boats, caravans and holiday cabins i.e. where grid connection might be too expensive or impractical.

With the use of an electrical control panel and an inverter the electricity generated can be used to supply electricity to the home, the amount of which depends on the size of the turbine installed, the demand at any given time and of course the wind available. An inverter is necessary for a number of reasons. One of its functions is to convert direct current (DC) to alternating current (AC) which is the type of power utensils and appliances demand i.e. 'mains' electricity. Direct current is outputted by the controller which is in turn supplied with power from the turbine. The inverter is also necessary to synchronise the output of the turbine with the electricity being drawn from the grid to ensure the occupant sees no interruption in their supply.