Demand Response

In electricity grids, demand response (DR) is a mechanism to manage customer consumption of electricity in response to supply conditions. Essentially, electricity customers reduce their consumption at critical times. Demand response can involve curtailing power usage or by starting on site generation which may or may not be connected in parallel with the grid. Demand response schemes are implemented with commercial customers to shed loads in response to a request by the local utility. Services (lights, machines, air conditioning) are reduced according to a preplanned load prioritization scheme during the critical time frames. An alternative to load shedding is on-site generation of electricity to supplement the power grid.

 

Electricity Grids and Peak Demand Response

In an electricity grid, electricity consumption and production must balance at all times; any significant imbalance could cause grid instability or severe voltage fluctuations, and cause failures within the grid. Total generation capacity is therefore sized to correspond to total peak demand with some margin of error and allowance for contingencies (such as plants being off-line during peak demand periods). Demand response is targeted at reducing peak demand to reduce the risk of potential disturbances.

 

Load Shedding

Electrical generation and transmission systems may not always meet peak demand requirements— the greatest amount of electricity required by all utility customers within a given region. In the effort to reduce the electric demand on power grids at critical periods, researchers developed a ballast prototype that quickly and reliably sheds the electric load within a building’s lighting system. A load-shedding ballast is an instant-start ballast with bi-level dimming and a built-in power line carrier (PLC) signal receiver for automated dimming response.