The Centre for Alternative Technology (CAT) in Machynlleth, Wales has unveiled the UK’s first island micro grid. The system will allow companies to generate their own renewable energy while still remaining connected to the national grid.

CAT designed a micro-grid that uses wind, hydro and solar energy coupled with an intelligent control system to connect and disconnect to the national grid whenever they need to.

The system, also known as island generation, is the first of its kind in the UK. It is conceptualized to enable communities to control their energy use and reduce their carbon footprint.

Centralized electricity systems waste around 65% of energy through heat loss in power stations and transmission lines.

The renewable energy produced at CAT is fed into a battery bank and connected together through an intelligent electric control system along with the load and the national grid. At normal operation, the renewable generator provides power to all the load and the excess power is exported to the grid.

In the event of a power failure, the CAT electricity system will be isolated from the national grid but the renewable generators will continue to operate.

The intelligent electronic control system will regulate the power generation according to the demand of power. This ensures a continuous efficient operation or renewable generator to achieve the Zero Carbon CAT policy.

The micro grid system will make sure that all the renewable generators at normal conditions will generate electricity and will deliver electricity to the precision mains load as first priority and then to the raw mains power. The excess electricity will be then exported to the national grid.

The back-up battery also ensures that if there is no wind, sun, water or biomass it will provide power for at least three hours. After a certain period of time without any generation and the energy stored in the batteries is too low, the system will disconnect the power to precision mains power and make sure the energy is available for the wise emergency lights, servers and telephone system.

The system will be used for the courses and consultancy as a model for Zero carbon CAT. This will be a demonstration project for small communities interested in island grid or micro grid systems.


-   Katrice R. Jalbuena