Island mode refers to a system that is operating independently to the utility and can also be commonly known as “off-grid” generation.
A CHP system is typically interconnected to the utility and operates “in parallel” with the utility when it is healthy. When the utility fails and is “Unhealthy” a Synchronous Cogeneration system will swop over into “island mode” and provide convenience power to a facility or group of facilities (microgrid) to keep it/them operational during a utility outage.
Island mode refers to a plant is not, or no longer, connected to other power plants or utility source. Remote towns and mine sites often have island mode power plants as opposed to larger cities and dense population areas where multiple power plants provide power to a grid. Island mode units also act as standby or backup units to provide electricity.
A gas engine is inherently more sensitive than a Diesel engine and therefore when operating in Island Mode the loads have to be introduced in a controlled sequential manner hereafter referred to as “Load Steps” in order to prevent the system from tripping due to a single large load step being introduced.
When in Island Mode the CHP capacity is reduced to 80% of nominal output and the individual load steps must not exceed 30% of the Island mode rating (80%) and should be initiated approximately every 15 – 20 seconds.
Martin Energy Group standard CHP unit will stop when the grid power supply to the site fails. The unit will then Auto-start in Island mode, subject to the system design.
The CHP system will require a heat rejection system to allow full standby electrical power output. This can be the site heat load or the heat rejection radiator. Please note that the power supply to the pumps and/or radiator will be taken from the CHP system.