A diesel engine converts the energy contained in the diesel fuel into mechanical, which turns a generator and makes electrical energy.

Hydro operates 25 diesel plants, which provides electricity to many communities along the coast of Newfoundland and Labrador. The majority of Hydro's diesel plants are located along coastal communities in Labrador.

Learn more about Hydro's diesel plant locations and capacity.

Most of Hydro's diesel plants are operated by automatic controls, and there are many advantages to automating a diesel plant. If a plant is automatically controlled, the automation scheme will start and stop engines based on how much electricity is required to meet the demand from consumers. When more generation is required, the engines automatically start and when generation is not required, the engines automatically turn off.

Newer control systems in some of Hydro's diesel plants can detect when there is a problem with one engine and automatically turn on another before powering down the problem engine. In addition, these plants have better fuel efficiency, as the engines will only be running when absolutely necessary.

Even though many diesel plants are automatically controlled, most communities that receive their electricity from diesel plants have either a full-time or part-time operator living in the community who can respond to any emergencies that may occur on site and complete regular maintenance.

Hydro is investigating renewable energy sources for diesel communities in the province. The company is currently evaluating the potential for small-scale hydroelectric sites and wind generating sites to reduce these communities' reliance on diesel generation. To support efforts of identifying alternative sources of energy for Labrador's coastal communities, the Provincial Government announced in June 2011 the start of the Coastal Labrador Wind Monitoring Program under Phase Two of the Coastal Labrador Alternative Energy study. Hydro is currently managing this project on behalf of the province.

Phase One of the study identified alternative energy sources that have the potential to provide some level of clean renewable power to residents on Labrador's coast who are currently serviced by diesel generation. The results of this initial phase provided valuable information on the region's resource potential and areas for further examination, such as wind and small-scale hydroelectricity.

In addition to the Wind Monitoring Program, Hydro is furthering investigation at the hydroelectric sites identified in Phase One of the Alternative Energy Study. Currently ongoing, the analysis includes preliminary investigations at the sites shown to be competitive against the cost of diesel fuel, and/or capable of displacing one or more diesel plants. This study includes more detailed engineering and environmental assessments, cost estimates, and detailed surveying and mapping.

Hydro's parent company, Nalcor Energy is also making an effort to reduce reliance on fuel-fired generation. Nalcor has built one of the first projects in the world to integrate generation from wind, hydrogen and diesel in an isolated electricity system. The Wind-Hydrogen-Diesel Energy Project in Ramea is a research and development project that uses renewable energy sources to supplement the diesel requirements of the island community. Nalcor will finalize commissioning and embark on the demonstration phase of the project in early 2012. The demonstration phase involves studying the operation of the facility, analysing collected data and considering issues around the role this technology can play in an isolated electricity system.