Power Generation

All power plants are created with one particular goal: to produce electric power as efficiently as possible. There are several types of power plants depending mainly on the sources of energy that are used. The introduction of more sustainable forms of energy has caused an increase in the improvement and creation of particular power plants.

Thermal power plants

Thermal power plants are split into two different categories; those that create electricity by burning fuel and those that generate electricity via prime mover:

• Fossil fuel power plants: Generates electric power by burning fossil fuels like coal, natural gas, or diesel.
• Nuclear power plants: The controlled nuclear reaction is maintained to generate electricity.

Hydroelectric power plants

Hydroelectric power plants use energy from falling water in rivers and reservoirs to spin a generator and create electricity. This energy source tends to be more reliable (dispatchable) than other renewable resources, especially when the facility runs off of a reservoir.

Solar power plants

Solar power plants convert sunlight into electricity, either directly using photovoltaics (PV) or indirectly using concentrated solar power (CSP). Concentrated solar power systems use lenses, mirrors, and tracking systems to focus a large area of sunlight into a small beam.

Wind power plants

Wind power plants / Wind turbines convert the kinetic energy from the wind into mechanical power. This mechanical power can be used for specific tasks (such as grinding grain or pumping water), or a generator can convert this mechanical power into electricity.

How do power plants work?

Electrical power starts at the power plant. In most cases, a power plant consists of an electric generator. Something has to spin that generator — it might be a water wheel in a hydroelectric dam, a large diesel engine, or a gas turbine. But in most cases, the object spinning the generator is a steam turbine. The steam might be created by burning coal, oil, or natural gas. Or the smoke may come from a nuclear reactor.

Electricity is a secondary energy source, which means that electricity is obtained from converting other primary sources of energy, such as coal, natural gas, nuclear, solar, or wind energy. The power plant is the location in which the energy conversions take place.

Electricity generation generates electricity from primary energy sources, such as coal, natural gas, nuclear, solar, or wind energy.

The power plant generator is a device that converts mechanical energy obtained from an external source into electrical energy as the output—understanding that a generator does not actually ‘create’ electrical power. It uses the mechanical energy supplied to it to force the movement of electric charges present in the wire of its windings through an external electric circuit.

The power generation industry can be split into three areas: power generation, transmission and distribution networks, and metering and sales. Large energy companies tend to operate in all three areas, which is more cost-effective, but smaller companies often only work in one of these areas.

Each electric power station’s technology has advantages and disadvantages. For example, nuclear power plants provide large quantities of reliable power with low levels of greenhouse gas emissions. Fossil fuel power plants deliver on-demand, consistent and reliable energy when the resources are available. Hydro, solar, and wind power plants generate renewable electricity, producing emissions-free electricity.

Boiler feedwater pumps, condensate extraction pumps, circulating water pumps and a long list of auxiliary and lubrication pumps keep a plant running. Feedwater pumps in particular work at high pressure and temperature and are among the most critical rotating machines on the site. More in Pumps and Pumping Systems.

Feedwater, steam, cooling water and fuel flow all need measurement, from differential pressure and vortex meters on steam to ultrasonic and magnetic meters on water. Heat rate and efficiency calculations are only as good as those readings. More in Flow Control and Measurement.

Drum level is one of the classic safety and control loops: too low and the tubes overheat, too high and water carries over into the turbine. Three element control combines drum level, steam flow and feedwater flow to keep it stable during load changes. More in Level Control and Measurement.

Turbine control and stop valves, high pressure bypass valves, feedwater regulating valves and safety relief valves all work at severe pressure drops and temperatures. Trim design and material choice decide whether a valve survives cycling or erodes within a season. More in Process and Control Valves.

Pressure control runs from the boiler drum through the steam header to the condenser vacuum, and it decides both efficiency and safety. Plants that follow a fluctuating grid cycle far more often than they were designed for, which puts extra load on pressure parts and instruments. More in Pressure Control and Measurement.

Online conductivity, pH, dissolved oxygen, sodium and silica measurement protect boiler and turbine against corrosion and deposits. A chemistry excursion that goes unnoticed for hours can cost far more than the analyser that would have caught it. More in Process Gas and Liquid Analytical Systems.

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