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Gas turbines (more commonly referred to as Jet Engines) are used around the world to generate electricity. The Gas turbine is anchored to the ground, and the thrust generated from the engine is used to spin a generator (which in turn generates the electricity). The generator feeds into a transformer which can then be attached to a local grid. Unit's can be configured to match the local supply voltages and frequencies.

These gas turbines are often referred to as Industrial Gas Turbines to differentiate them from their aerospace versions. For instance a common gas turbine is the Rolls-Royce Olympus. In it's aerospace configuration it powered Concorde and the cold war era Vulcan bomber. It's industrial cousin can be manufactured from cheaper heavier material (saving weight is not as much of a concern for industrial gas turbines). As an aside the Olympus is also used in a marine configuration on many boats (notably the British Invincible class of Aircraft Carrier, and the Type 21 Frigate which switches over to two Olympus turbines to go to "intercept speed") 

Industrial gas turbine units can be quite small (a 2 megawatt unit containing turbine, generator, transformer and control room might typically take up a 20' by 40' footprint (6m by 12m), with an overall height of about 20' (6m). Such units can be mounted either inside or outside of the building. 

On the whole, gas turbines are used for either main power or backup power. Here are some examples of these scenarios in which people have found a use for gas turbines.

Main power for remote facilities that are not connected to the national power grid.
- Many remote oil wells use gas turbines to provide their power requirements
- Off shore oil rigs are particularly suited to using gas turbines as they can usually use the gas from the well as fuel, rather than flaring it off into the atmosphere. This results in great savings as it reduces the cost involved in shipping diesel fuel to the rig for reciprocating power generation.
- The Trans-Canada pipeline uses gas-turbines extensively to pump oil across the North American continent. 

Main power where the co-generation capabilities of the turbine can be used.
- Gas turbines produce a lot of heat. In many cases this can be used by businesses either in their processes or simply to heat the work area and water or to produce steam. 

Backup Power for factories, hotels, hospitals and office buildings.
- Many businesses can justify the use of gas turbines simply based on lost time costs due to power blackouts. Gas turbines are particularly suited to emergency power generation as they have a very short spin up time, and can typically be producing power within a minute or so. 
- Nuclear power-stations use gas turbines to provide emergency shut-down power to drive pumps and cool the reactors.

A single gas turbine package can provide anywhere from 2 megawatts up to 500 megawatts (depending on the type of engine). Smaller engines are available but do not usually have the efficiency rating to make them viable in business and are usually employed for very specific tasks (such as the Abrams M1 tank which uses one as it's engine). 

Gas turbines lose efficiency at lower speeds, so it is important to size the engine correctly to the task. There is no point in putting a 30 megawatt unit into a building that only requires 2 megawatts as the engine will never run very efficiently. Luckily there are a wide range of models available.

Multiple units can also be provided which ensure greater reliability and far more flexibility.

Gas turbines also lose and gain efficiency dependent on weather conditions. When the power rating of an engine is quoted, it is usually taken to be ISO standard which is 15°C at sea level. Cooler air will generate more power (as it is more dense) and warmer air will generate less power. These variables are factored in to the power calculations when sizing a unit.

Once a gas turbine has been started then it is simply controlled by a fuel valve. Opening the fuel valve increases the power and closing the valve decreases it (or if closed far enough, stops it). As different power demands are made of these engines the valve must react quickly to prevent either stalling the engine or over-speeding the engine. Because of this, engines are typically controlled by a computer system called a PLC (Programmable Logic Controller) which reacts to the engine and keeps it running in a safe and optimal manner. This PLC and it's program are generally referred to as the "control system". The control system monitors engine vibration, speeds, temperatures etc and will ensure that the engine runs within it's operating parameters and will also shut the engine down the instance it detects a failure. 

Although the PLC will control the engine quite happily without human intervention, one or more personal computers can be networked to the PLC to monitor engine parameters, graph performance or to manually start and stop the engine. The programs running on these pc's are called the HMI (Human Machine Interface). 

The whole system (turbine, generator, transformer, control system, HMI etc) is often referred to as the "package". 

Gas turbines have a very long life span, and many 30 year old models are still operating smoothly today. After time however, like any mechanical device they will require inspection and possible maintenance in order to keep them at peak performance. This will either involve an internal inspection (using a borescope) or a physical strip down and rebuild of the engine. Orbital Energy provides both these services, either on-site or at one of our factories. Once an engine has been rebuilt it is usually tested in a test cell which is a custom built facility to ensure that the engine is running to original specification. In this way, even refurbished engines can be guaranteed to be almost as good as the day they were originally manufactured.

Once an order has been placed, it typically takes from 30 days up to 6 months to manufacture, test and ship the whole package. (Timescales vary depending on size of engine and complexity of control system required)

Orbital Energy will handle the shipping of the package around the world (usually by train and/or sea-freight) and once an engine has arrived on site Orbital engineers will oversee the installation and commissioning of the package.