Marine expertise helps to deliver power to remote locations
Remote, fixed-base power generation stations operate much like ships at sea, says ExxonMobil’s Carol Fisher.
Nearly a third of the world’s people are without access to commercially available electricity. Many live in isolated and remote sections of South America, the Caribbean, Asia Pacific, Africa and the Middle East, where the market for stand-alone power generation units is rapidly growing.
The primary areas where diesel marine power plants provide electricity. It is in these areas where expertise in marine diesel lubricants can bring cost savings for remote power generators
About seven per cent of the world’s electricity is produced off-grid near the point of use, using a variety of technologies and fuels. This decentralized energy – as off-grid electricity is called – is generated at fixed, land-based stations.
As nations begin to industrialize, the market for power generation is growing rapidly. About half of all medium-speed diesel engines built are now used for power generation. In the last five years, 21 000 units were ordered worldwide – 20 per cent more than during the preceding 15 years.
The right lubricants make production of electric power in these remote locations more cost-effective and reliable and thus are key to economic development and human well being. Lubrication lessons learned by ExxonMobil on ships at sea are helping nations generate reliable supplies of electricity for millions of their citizens.
“Fixed, land-based power generation stations are like ocean-going vessels,” says Charles Foster, global energy lubricants advisor, ExxonMobil Lubricants & Specialties. “They often use the same medium- or slow-speed diesel engines that propel ships at sea, and they face the same maintenance challenges to increase oil-drain intervals and reduce costs. Since the 1880s, ExxonMobil has been lubricating marine engines around the world. As the leading lubricants supplier to the marine industry, we are in a unique position to solve problems on land-based engines that we have been solving for years at sea.”
Like their counterparts on ships, many medium-speed marine diesel engines work under conditions that present new challenges. Newer engines are more demanding of the oils that lubricate them. They operate with a much lower specific lube oil consumption rate than they did just a few years ago. At the same time, greater availability of lower-quality residual fuels combined with higher injection pressures has led to an increase in fuel leakage from pumps and injectors into an engine’s lube oil sump. Contamination of lubricants from unburned fuel has also become increasingly common. The combined result can be a dirty engine with sludge in the crankcase and excessive deposits in such critical parts as the piston undercrown and ring belt.
Based on its experience with engines used in ships, ExxonMobil is finding new ways to solve problems faced by managers of stationary power generation stations. These include:
- New oils: In February of 2003, ExxonMobil introduced Mobilgard M Series Oils in response to strenuous operating demands on medium-speed marine diesel engines. These lubricants have a balanced additive and basestock formulation that enables them to handle high sulphur fuels superbly, promote cleanliness and decreased wear. They can also save operators money by increasing oil-drain intervals and minimizing downtime.
- Research: ExxonMobil has a long-term commitment to research and development. Among its R&D capabilities is an affiliate owned and operated research facility in Gravenchon, France, that houses a full-sized, land-based Wärtsilä (Sulzer) RTA crosshead diesel engine that is used to evaluate marine oil formulations quickly under true test conditions. Explorer, as the test engine is called, began operating more than ten years ago. It runs on heavy fuel oil with around 3.4 per cent sulphur and, like working land-based stations with marine engines, provides electric power locally.
- Maintenance Service: ExxonMobil has made it easier for managers of stationary power plants to monitor the condition of lubricants, engines and auxiliary equipment using the Signum Oil Analysis Program. This incorporates unique online capabilities that help customers manage maintenance and control their costs by providing a clear picture of the condition of power plant lubricants, diesel main engines and auxiliary engines. The program is available to power plant operators throughout the world, even in remote locations.
One key benefit for managers of fixed power generation sites is extending maintenance intervals on workhorse engines that may operate 24 hours a day in high-stress conditions. This often translates to substantial cost savings. Two examples include:
On the Island of Guernsey, between France and Britain, Guernsey Electricity saved £120 000 ($188 500) annually after major overhauls at its stationary power plant were extended from 6000 hours to 13 000 hours using ExxonMobil lubricants. Guernsey’s equipment includes Sulzer two-stroke crosshead diesel engines, also commonly used as propulsion units for ships.
At a stationary power plant in Pakistan, Genertech Pak, Ltd., saved Rs570 000 ($9764) per oil change when it began using an ExxonMobil lubricant that allowed it to extend oil drain intervals from 8000 hours to 13 960 hours in its Niigata 16V 32CLX engines.
“Stationary fixed power systems are bringing electricity to places that have no access to power grids,” says Foster. “As economies begin to improve and industrial development picks up, quality of life improves. Our expertise, gained from more than a century at sea, translates seamlessly to land and makes a positive difference for countless people.”
Nexans has signed a contract with France’s DGA (Délégation Générale pour l’Armement) for the supply of a superconducting coil that can store magnetic energy and convert it into electricity in the space of about one second. Such Superconducting Magnetic Energy Storage (SMES) systems can be used to stabilize a power distribution network or to energize electrical devices.
This superconducting coil will combine the technology of energy storage by magnetic induction – which allows an energy density of several million joules per cubic meter to be attained – with the use of superconducting materials which, thanks to their zero electrical resistance at the service temperature of -250°C, will make it possible to store this energy over long periods of time. The coil will be manufactured from high temperature superconducting tapes developed by Nexans at its Jeumont site in France. Its storage capacity will be 500 000 J.
Nexans’ HTS coil is capable of storing 500 kJ of electrical power and releasing it within a fraction of a second. The technology can be used to stabilize power distribution networks
The required service temperature of -250°C will be obtained through a cryogenic refrigerator, eliminating the need to use liquified gases. System testing and entry into service are scheduled for 2006.
Nexans’ superconducting tapes comprise about one hundred micrometric superconducting ceramic filaments embedded in a silver alloy matrix. The ceramic is produced by Nexans in its plant in Hürth, Germany. It is made up of oxides of copper, bismuth, calcium and strontium. The tapes, developed in Nexans’ Jeumont plant in France, are designed to optimize the performance of superconducting coils at temperatures of between -250°C and -230°C.
Security is a top priority
With rapidly changing perimeter security regulations set by the United States Nuclear Regulatory Commission (NRC) and heightened security at nuclear power plants, Southwest Microwave’s 300B Series microwave links have continued to meet the perimeter security requirements of nuclear power plants.
The Model 300B Series Outdoor Volumetric Microwave Link is well suited to short, medium and extended range detection from 30 m to 183 m. Several technological advances make the sensor ideal for utility applications such as nuclear power plants, where unassailable security is a must. One case in point is Pacific Gas and Electric’s Diablo Canyon nuclear power plant in California.
“We’ve been working with Diablo Canyon nuclear power plant since the late 1970s,” said Tom Wallace, national sales manager for Southwest Microwave. “As the NRC’s requirements for intrusion detection criteria increased, there was a need to provide a higher field of detection so Southwest Microwave developed a double and triple stacked configuration at the site for continuous compliance.”
The stacked configuration of Southwest Microwave’s 300B Series microwave sensor provides a ‘wall’ of perimeter intrusion detection
Diablo Canyon has been utilizing the stacked 300B Series links to provide a ‘wall’ of detection for walking, running or crawling intruders, according to Wallace. Unlike lens-based intrusion detection sensors, the Model 300B Series microwave sensors are unaffected by vibration, wind, fog, rain, snow and temperature extremes. The Gallium Arsenide Field Effect Transistor (GaAs FET) microwave source allows the sensor to operate with very low current drain.
ScottishPower opts for cold shrink
3M and PowerSystems, part of the UK’s ScottishPower group, have signed a deal worth £2.6 million over the next two years. This will see 3M’s Cold Shrink joints and terminations used with all of PowerSystems’ 11 kV new polymeric and legacy paper cabling.
The partnership also involves Sicame Electrical Developments, who will provide custom packed kits direct to PowerSystems’ sites. For the Electrical Products division of 3M this is the largest deal ever struck in the UK.
Having chosen to install polymeric rather than paper cabling with its 11 kV cables, PowerSystems undertook a rigourous search to find a company that met its requirements for safety, quality and value for money. After in-depth testing of products from four suppliers, 3M was chosen on the strength of over 20 years’ experience of cold shrink technology and a competitive solution.
3M’s patented Cold Shrink technology offers a safe, reliable and speedy alternative to heat shrink. There is no need for heat or flames, meaning that the joints and terminations can be used without the need for hot work permits in hazardous areas such as on an oil rig. As well as the safety implications of using a flame in certain situations, heat shrink can be difficult to install correctly and consistently, leading to problems such as moisture penetration or discharge. 3M has eliminated this potential risk by making the joints simple to install.
Loos offers boiler innovation
Loos has been offering modular solutions in the industrial and commercial heating and steam sector for many years. With the newly developed Loos condensate service module type CSM and the Loos blow-down, expansion and cooling device module type BEM, the successful boiler house module series is now being supplemented by two important elements and the product programme rounded off.
The CSM condensate service module takes up condensate forming in the system and supplies the feed water deaeration plant. The CSM is delivered as a ready-to-use unit, complete with digital controls, condensate pumps, insulated condensate tank and associated equipment.
The newly developed CSM and BEM modules from Loos offer a range of advantages for planners, system designers and operators
The BEM blow-down, expansion and cooling device module for the expansion and cooling of all temperature-carrying waters in a steam boiler system consists of the insulated sheet steel tank made as a mixer cooler and is ready to use as a complete unit including electronic temperature sensor.
Earlier, all sorts of individual components had to be dimensioned, delivered and assembled to create a functioning unit, often under extremely difficult conditions; but today, the fitting of boiler houses is easier than ever before.
Hydrogen monitors maximise generator performance at Didcot
Hydrogen purity analysers from ABB Limited have been supplied to Innogy’s 2000 MW Didcot A power station to help maximise generator efficiency at the plant. The four Analyze hydrogen purity monitors will be used to measure the concentration of hydrogen used to cool the generators during operation.
The four ABB Analyze hydrogen purity monitors will be used at Didcot A to measure the concentration of hydrogen used to cool the generators during operation
Approximately seven times more thermally conductive than air, hydrogen is perfect for removing excessive heat, making it an ideal coolant for generator applications in the power industry. It is also less dense than air, which helps to optimize generator performance by reducing windage losses caused by drag.
The monitors have been supplied as part of an upgrade and will replace existing units which have been in use for over 30 years.
Once installed, the monitors will help to ensure that the generators are running with as close to 100 per cent hydrogen as possible. Each percentage drop in hydrogen purity can lead to windage losses that can greatly reduce generator efficiency. A reduction of eight per cent purity on an 800 MW generator, for example, could cost around £2500 per day.
Allweiler bags international orders
Allweiler AG will deliver eight fuel skids and eight purge-water facilities for a new power plant in Kuwait, and will also help enlarge an existing power plant in Indonesia with the addition of six fuel skids. The company overcame strong international competition to win the two orders, worth a total of g2.7 million.
The German pump specialist will provide all fuel skids and rinsing-water facilities for the Az Zour power plant, located approximately 80 km south of Kuwait’s capital. The power plant can run on both natural gas and petroleum. When completed in 2005, it will feed power into the Kuwaiti power grid.
The Kuwaiti ministry for electricity and water resources selected Siemens AG’s power generation group to be the main contractor for the project.
In Indonesia, Allweiler AG will provide six fuel skids for an existing plant in Muara Tawar, 25 km northeast of Jakarta. The plant, owned by Java-Bali Power, is to be enlarged with six new gas turbines that will produce 150 MW of power each. The new units will be run on heating oil and are expected to go into operation in April 2004.
Allweiler won the Indonesian contract thanks to its specialized knowledge of selected pumps and valves used in fuel skids, as well as its reputation for meeting deadlines.
VA Tech scoops Czech hydro contract
Austria’s VA Tech Hydro has won a contract to assist Czech electricity producer CEZ to reconstruct the generators of a major hydropower plant. The g2.9m contract involves reconstructing two of the four generators of the Orlik hydropower station.
The 100 MW Orlik plant has been out of operation since major floods that occurred in 2002. It is a fundamental part of the Vltava Cascade, the largest retention reservoir in the Czech Republic.
VA Tech Hydro will supply equipment and services to the project, including delivery and erection supervision of two stator windings, and cleaning of the stator core and rotor.
VA Tech Hydro has also won a contract from Enel Power Spa Milan for a hydropower plant modernization in northeast Italy.
HV motor and switchgear test reduced to 30 mins
Wyko’s Condition Monitoring unit has developed a new highly accurate method of partial discharge detection testing for High Voltage (HV) systems, including motors, switchgear and transformers. The test takes only a matter of minutes to complete and can be carried out while HV systems are in normal operation, as opposed to traditional test procedures such as dielectric loss analysis that can take up to 12 hours per machine and requires the system to be shut down.
The result is a complete HV systems health check that can be carried out using a set of small coils and a suitcase sized detector rather than a large vehicle full of support equipment. Any power generation installation can now have a complete HV systems health check carried out by Wyko without disrupting normal operations.
Since the test can be carried out quickly and easily, more regular checks are practical and the risk of poor system performance or failure and unplanned downtime can be greatly reduced. It is estimated that many companies only test their HV equipment as infrequently as every five years; this can prove a serious issue as problems can develop over a much shorter time period.
The new partial discharge detection test takes only a matter of minutes to complete and can be carried out while HV systems are in normal operation
The new partial discharge detector has been a joint development between M&B Systems (Power Instrumentation Ltd.), HV Solutions Ltd. and Wyko. It has been designed primarily for use with Rogowski coils; the main advantage of the coils is that they provide feedback in a non-invasive way.