Gas Turbine & Microturbine Generators


VIRIDIS provide various tailored solutions to suit client’s requirements for gas turbine and microturbine generator systems such as :

  • Feasibility Studies
  • Equipment Supply
  • System Integration
  • Construction
  • Operations & Maintenance Contracts
  • Build Own Transfer (BOT) / Build Own Operate (BOO)
  • Maintenance
  • Spares

 

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What is a Microturbine?

Microturbines are small combustion turbines approximately the size of a refrigerator with outputs of 30kW to 1000kW for a single unit. They evolved from automotive and truck turbochargers, auxiliary power units (APUs) for airplanes, and small jet engines. Most microturbines are comprised of a compressor, combustor, turbine, alternator, recuperator (a device that captures waste heat to improve the efficiency of the compressor stage), and generator.

Working Mechanisms

The high velocity exhaust gases coming from the combustor rotate the turbine used in the micro turbine. The basic principle of working of the micro turbine is that the compressor as well as the electric generator is mounted on the same power shaft as that of the turbine. Because of this the compressor and the generator also rotate with the turbine. The generator rotates with the same speed as that of the turbine and generates the electricity. The electricity is first given to the power conditioning devices and then it is supplied to the required areas. The combustor is supplied with the fuel in the gaseous form by the gas compressor. Also fresh and compressed air is supplied to the combustor by the compressor through the recuperator. Here the recuperator plays an important role of heat exchanger. It absorbs the heat from the hot gases coming from the turbine. Then it gives this heat to the compressed air coming from the compressor. Thus the air supplied to the combustor is hot and compressed. This helps to increase the overall efficiency of the cycle.

Advantages

  • Few moving parts
  • Compact system
  • Good efficiency in coregeneration
  • Low emissions
  • Can utilize a variety of fuels (including waste fuels)
  • Low investment costs
  • Low maintenance costs

 

Applications

  •  OIL, GAS & OTHER NATURAL RESOURCES

Microturbines align perfectly with the needs of the oil and gas industry and are currently used in all phases of oil production including upstream, midstream, and downstream operations in both onshore and offshore applications. Microturbines provide the low operational cost, high availability, and high reliability oil producers need.

  • CRITICAL POWER SUPPLY

Traditional backup generation sets are often considered only as idle assets and can be unreliable when you need them the most. Mission critical facilities require a power generation solution that is more reliable and efficient than what a typical utility can provide. Capstone’s critical power supply portfolio features the world’s only microturbine-powered Uninterruptible Power Source (UPS) solution that delivers the reliability and performance critical facilities require. When operating in “Dual Mode”, microturbines can easily transition from continuous power mode to standby power mode.

  • RENEWABLE ENERGY

With the use of an anaerobic digester, microturbines are able to cleanly and effectively run on methane gas from landfills, wastewater treatment facilities and food processing facilities, as well as agriculture waste, which is often referred to as “green waste.” Rather than simply venting or flaring the methane gas, microturbines can convert this free fuel to clean and reliable electricity for use at the site or surrounding areas. We can engineer a line of microturbines specifically designed to operate on waste gas fuels.

  • ENERGY EFFICIENCY

Energy efficiency refers to the proper utilization of both electrical energy and thermal energy in the power production process. Microturbines can be easily integrated to capture thermal energy produced from the exhaust to provide a significant economic advantage to end users. Microturbines can achieve overall efficiency levels of up to 80 percent in combined heat and power (CHP) applications and up to 90 percent in combined cooling, heat and power (CCHP) applications.

  • TRANSPORTATION

Electric vehicles are clean and efficient, but limited in the distance they can travel between battery charges. Microturbines are used in hybrid electric vehicle (HEV) applications as a range extender, acting as an onboard battery charger for increased fuel economy, quieter operations, reduced emissions, and higher reliability. Thus, the need for daytime battery charging or battery swapping is eliminated.

  • MARINE

Microturbines can be used in marine applications to provide onboard auxiliary power or as a range extender for both luxury yachts and commercial vessels. Microturbines can operate on diesel and liquefied natural gas (LNG). The increased use of LNG in onboard marine applications is ideal for microturbines because they can run on the boil-off that naturally occurs with LNG storage, essentially providing free power from a source that would otherwise go to waste. This helps to increase overall efficiency while simultaneously reducing the carbon footprint of the vessel.

  • FLOATING PRODUCTION STORAGE AND OFFLOADING (FPSO)

Oil produced from offshore production platforms can be transported to the mainland either by pipeline or by tanker. When a tanker is chosen to transport the oil, it is necessary to accumulate oil in some form of storage tank, such that the oil tanker is not continuously occupied during oil production, and is only needed once sufficient oil has been produced to fill the tanker. FPSO vessels with Natural Gas availability can be used to operate microturbines in combination with a large back-up diesel generator, the turbines also provide ample waste heat for crude heating.

Comparison between Microturbine and Piston Engine

Microturbine systems have many advantages over reciprocating engine generators, such as higher power density (with respect to footprint and weight), extremely low emissions and few, or just one, moving part. Those designed with foil bearings and air-cooling operate without oil, coolants or other hazardous materials. Microturbines also have the advantage of having the majority of their waste heat contained in their relatively high temperature exhaust, whereas the waste heat of reciprocating engines is split between its exhaust and cooling system.

S.no Gas Turbine Steam Turbine
1. In gas turbine the compressor and combustion chamber are the important components. In steam turbine the steam boiler and accessories are the important components.
2. Less space for installation is required. More space for installation is required.
3. The mass of gas turbine per kW produced is less. The mass of the steam turbine per kW produced is more.
4. Less installation and running cost.  More installation and running cost.
5. With the changing load conditions, its control is easy. Its control is difficult, with the changing load condition.
6. The starting of this turbine is easy and quick. The starting of steam turbine is not easy and takes long time.
7. A gas turbine does not depend on water supply. A steam turbine depends upon water supply.
8. Its efficiency is less. Its efficiency is high.
  • Piston engines have reciprocating mechanisms (to and from motion) while microturbine engines have rotary mechanisms.
  • Both use the air as the working fluid, but the flow in microturbine is continuous while reciprocating engines have an intermittent flow.
  • Power to weight ratio of the microturbine engines is much higher than that of reciprocating engines.
  • Microturbine are sophisticated in design and manufacture, while reciprocating engines are simpler in design and easier to manufacture.
  • Maintenance of the reciprocating engines are simpler and has to be performed frequently, while maintenance of the microturbine engines is complex, but the inspection and maintenance occurs at longer intervals.
  • Microturbine engines or its variants are expensive, while reciprocating engines are relatively inexpensive.
  • Microturbine engines power large and powerful aircrafts such as military jet fighters or commercial airliner, but piston engine are being used in smaller and short ranged aircraft.