Editor’s Note: Diesel & Gas Turbine Worldwide invited prime-mover original equipment manufacturers to submit one specific power generation project it feels merits special attention because of advances in one or more of the following areas: efficiency increase, environmental aesthetics, operation characteristics, emissions improvements or construction principles. The coverage is limited to plants commissioned during the 2017 calendar year. Here are this year’s submissions.
Wärtsilä Moves Mountains
A plant which has been operational for less than a year is playing a major role in the north of Oman.
The facility started supplying uninterruptible power in April 2017 to the Governate of Musandam.
Finnish technology group Wärtsilä was awarded the engineering, procurement and construction contract for the 120 MWe Musandam Independent Power Plant (MIPP) in November 2014 with a 15-year service agreement and five-year operation and maintenance agreement.
Wärtsilä said the MIPP is the first dual fuel power plant with combustion engines in the Gulf Cooperation Council, a political and economic alliance of six Middle Eastern countries, and the only power plant supplying smart electricity to the Musandam Grid in the Sultanate of Oman.
Musandam IPP is jointly owned by LGI from South Korea and Oman Oil, forming Musandam Power Co. Oman Power and Water Procurement Co. takes the electricity with the Rural Areas Electricity Co. the transmission system operator.
The plant uses natural gas from the Musandam gas processing plant and has a high open cycle efficiency, according to Wärtsilä.
The seasonal load variation in the grid can be between 10 MW and 100 MW which is handled by a multi-unit installation of 15, Wärtsilä 20V34DF engines with startup times of less than 10 minutes. The backup fuel operation with diesel is allowed only during emergency cases, thus providing fuel flexibility and the security of supply on the grid, Wärtsilä said.
Being the only power plant on the grid, MIPP is expected to provide 100% availability as no interruption would be accepted, especially during the summer period when the temperatures are as high as 50 °C.
Prior to MIPP, the Musandam Governate had only diesel-fired power plants which are kept on standby mode. As the plant is located next to the sea, Wärtsilä said it had to protect the marine environment throughout the construction of the plant. Wartsila received awards from the Ministry of Environment for monitoring the coral in the area and protecting the marine environment.
The company added that having the site very close to the international border between the United Arab Emirates and Oman had its own set of challenges with respect to approvals and permits, which were overcome, said Wärtsilä.
The company added that another challenge in the project was extensive earthworks involving blasting of a mountain and relocating 2.5 million m3 of earth and reclaiming the marine area.
The Musandam power plant which started supplying uninterruptible power in April 2017.
A Powerful First For MHPS
In October 2017, the Grand River Dam Authority (GDRA), a waterway control and development agency in Oklahoma, dedicated Unit 3 at its Grand River Energy Center in Oklahoma. Unit 3 is a 500 MW combined cycle power plant equipped with a Mitsubishi Hitachi Power Systems Ltd. (MHPS) M501J advanced class gas turbine. The turbine is the first J-Series turbine to be operational in the U.S. and is the first commercially available gas turbine that can reach 62% efficiency and sustain a turbine inlet temperature of 1600°C.
This new, high-efficiency combined cycle gas plant represents a US$500 million investment by GRDA reflecting it’s “grand and greener” long-term electric generation plan. Unit 3 is designed to provide long-term, low-cost, reliable electricity using a natural gas turbine, steam turbine and heat-recovery steam generators. According to a 2015 study by the Oklahoma Department of Commerce, the Grand River Dam Authority’s investment, operations, quality of life and power costs, facilitated an annual economic activity impact of US$960 million to a little over US$1 billion in Oklahoma’s economy during the first two years of Unit 3 construction.
The M501J turbine offers 62% efficiency – a global record for 60Hz machines, according to MHPS. The turbine offers a nearly 70% reduction in emissions compared to coal-fired generation as well.
As part of GRDA’s “grand and greener” plan, the organization is aiming to replace coal with wind and add a new gas-fired combined cycle plant. Environmental friendliness was a key factor in providing power to customers like a Google server center, just 5 miles from the GRDA plant site, MHPS said.
MHPS said it worked closely with all construction partners and Electronic Power Control contractors.
Other highlights, according to the company:
- The M501J turbine provides the lowest-cost electricity in the Southwest Power Pool.
- With improved 3D compressor blades, advanced combustor cooling and unique barrier coatings, the M501J turbine is one-of-a-kind and one of the most environmentally friendly power generation options available.
The MHPS turbine was delivered on time to the site, successfully achieved first fire on its first attempt, and two days later synchronized to the grid to produce electricity for GRDA and Southwest Power Pool customers. Fewer than 45 days after first fire, while operating in combined cycle, the test team successfully demonstrated sustained operations above GRDA’s “Sellable Power” milestone. The commissioning team achieved this contract milestone 35 days of ahead of the June 1 contract deadline.
MHPS is a joint venture by Mitsubishi Heavy Industries Ltd. and Hitachi Ltd. and is a leading global provider of thermal power generation systems and related technologies. With 20 000 global employees, and backed by 100 billion yen in capital, MHPS ranks among the largest providers of technology and services to the global power generation industry.
Rolls-Royce Keeps Growing Going
Rolls-Royce delivered two gas-powered gen-sets for two combined heat and power plants (CHPs) for a new tomato greenhouse in Meer, Belgium.
The gen-sets are based on the Bergen medium-speed B35:40 V12 AG2 engines, each of which can generate an electrical output of 5650 kW and a thermal output of 6545 kW. Rolls-Royce said they achieve an efficiency level of more than 96%.
In Meer, the electric power is used primarily for the greenhouse lamps and, if required, is fed into the public grid. The greenhouse, which extends over an area of 10.2 hectares, is heated using the heat extracted from the exhaust gas and the engine’s cooling system. The cleaned exhaust gases from the engines are also injected into the greenhouses to increase the level of CO² and boost plant growth. The annual production is expected to achieve 7.5 million kg of tomatoes.
Rolls-Royce has delivered the complete CHP plants, consisting of the power gen-sets, the exhaust gas systems including SCR systems, the heat exchangers, and the electronic control systems. Operator John Vermeiren and Rolls-Royce have concluded a long-term service agreement for the combined heat and power plants covering approximately 4500 hours of operation per year over the next 10 years.
Back in 2008 and 2010, Rolls-Royce delivered two combined heat and power plants to the greenhouse operator John Vermeiren in Loenhout and in Merksplas in Belgium.
“The high level of efficiency of the medium-speed gen-sets and their reliability impressed us so much that we decided once again in favor of Rolls-Royce for the energy supply of our third greenhouse in Meer,” Vermeiren said.
Since 2005, no fewer than 52 combined heat and power plants manufactured by Rolls-Royce have generated a total electrical output of 270 MW in greenhouses in Holland, Belgium, Russia and the UK.
MAN Diesel & Turbo Takes Care Of Leftovers
MAN Diesel & Turbo commissioned in 2017 a generator set of the type MAN 20V35/44G to Wykes Engineering in Rushden, UK. The engine generates up to 10.4 MW of electrical power from biogas at the power plant in central England.
The contract was completed in just eight months and the new gen-set supplements an existing 7L51/60DF engine that has been running on biogas at the power plant since 2014. The plant is used to back up the base load supply in the local electricity grid and now has a capacity of around 17 MW.
Wykes Engineering is a British engineering company specializing in machine and plant construction and in the construction and operation of power plants as an independent power provider (IPP), especially with renewable energies.
In Rushden, Wykes uses food waste such as meat waste, fruit juice and dairy products which have been deemed unfit for human consumption from a wide range of pre- and post-consumer sources across the food industry. As these waste products decompose in the fermenter, biogas is produced. This biogas is then utilized to fuel both the existing and the new engine to generate renewable power.
“The energy market in the UK is particularly interesting for us as power supplies and demand are subject to great volatility as a result of the decision to phase out coal, and this is having a direct effect on energy prices,” said Hajo Hoops, senior sales manager Gas Power Plants at MAN Diesel & Turbo. “Furthermore, Brexit will also mean largely autonomous power supplies. That will make it extremely exciting for MAN Diesel & Turbo in the years ahead.”
The energy system in the UK includes a so-called capacity market: generators are given additional remuneration for reserved capacities that should guarantee reliable supplies even at load peaks. This creates incentives for new investment, in particular for supporting renewables.
The biogas plants typically encountered in Europe often use maize and other agricultural products as a substrate and are usually operated with smaller, less efficient engines with output up to 1 MW. By contrast, Wykes achieves larger dimensions by industrially using food waste for the power plant in Rushden. By generating electrical power with a large engine and a downstream steam turbine process to generate additional electricity, the company now achieves close to 50% efficiency.
“The installation of the first engine with output around 7 MW was already a success. By expanding the power plant with the 20V35/44G, Wykes and MAN Diesel & Turbo are now demonstrating that the efficient use of biogas is also possible in the order of ten megawatts and more,” Hoops said.
Siemens Cuts Carbon
As an island with no geographic support from neighboring countries, the UK faces a particular situation that forces the National Grid to make a special configuration of the electrical distribution along the country.
The energy providers can’t supply at 100% of availability and there may be a lack of coal-fired plants soon. As such, the government carried out a plan called short-term operating reserve (STOR) that will rescue the country from unexpected high peaks (peak shaving) of demand when the base load supply is not able to support such a high consumption level.
National Grid selected Siemens to provide a standby engine solution to work at certain periods of time that will allow National Grid to cover peak high demand situations most efficiently.
Thirty-seven containerized Siemens SGE-56SL fast-response gas generator sets were delivered to three different sites in less than 16 weeks. Nominal output for each gen-set is 1059 kWe at 400 VAC. These 12-m, ISO-noise-insulated containerized Siemens gen-sets that include engine heat cooling equipment and power control were installed in three different areas of the UK: 19 at Exeter; six at The Drove; and 12 at Lesterway.
The modular design of these three plants enables fast equipment interchangeability and is easy to construct/disassemble and move from site to site as needed. These light-duty engines run around 2000 operating hours/year and have a life cycle of 30 years before an overhaul.
The units’ configuration improves the scheduled maintenance interventions, consequently reducing operating expenditures. Further to this, this type of gas engine is 10 times less pollutant (NOx and particulates emissions) than an equivalent diesel gen-set and complies with the EU 2015/2193 Medium Combustion Plant Directive for emissions that was passed into UK law in December 2017. This new law, published in late 2015, applies to all combustion plants rated between 1 and 50 MW thermal input.
Local staff received training from Siemens gas engine experts to ensure proper maintenance techniques needed to maximize the engines’ operating lives. In addition to the gen-sets, Siemens also provided the following:
• Proven technology with high efficiency and minimum emissions level
- Low initial CAPEX and OPEX
- Ability to run full-load from cold start in less than 60 seconds
- Short delivery time (16 weeks)
- High reliability and availability for heavy start/stop applications
- Easy commissioning and maintenance schedules.
A Peak Application From MTU
At 2962 m, the Zugspitze is the tallest mountain in Germany. Since 2017, visitors have been able to reach its peak with a new aerial cable car that covers more than 3200 m from base support pylon to summit.
The cableway is said to traverse a greater single-span distance than any other aerial cable system and to have the world’s tallest steel support pylon (127 m). Its total length of 4.5 km overcomes a difference of around 2000 m in altitude. Each cable car can carry 120 passengers with the system transporting up to 580 people an hour.
The cableway has its own medium-voltage power grid that is also fed by a cogeneration station. Two MTU diesel engines Series 2000 have been chosen for the generator sets that deal with possible power outages.
The 18-cylinder Series 2000 engines are used in the gen-sets by Germany-based manufacturer Polyma Energy Systems GmbH. The two gen-sets deliver 1 250 kVA of electricity each and can ramp up to peak performance within 15 seconds.
The generators can also operate in parallel with the medium-voltage grid, so that the monthly test run can take place without interrupting operations.
“If the power were to fail, the cableway would come to a brief stop. But as soon as the MTU engines were running, it would start up again to resume normal service,” explained the Rail Operations Manager responsible for power supply systems at the cableway operator Bavarian Zugspitzbahn, Matthias Ferchl.
Caterpillar Offers A Fortified Solution
In 2017, Caterpillar Energy Solutions delivered a generator set to the borough of St. Lorenz-Süd in the city of Lübeck, Germany. What is most peculiar about this gen-set is that it has been installed for cogeneration purposes in an air raid bunker from WW II.
The 20-cylinder TCG 2020 gen-set of the MWM brand powers a power-to-heat plant with an electric output of 2000 kW and thermal output of 2500 kW. The gen-set—which has a total efficiency of 90.2%, according to the manufacturer—supplies 1 200 local households. The cogeneration plant includes engine, burner, boilers, and two water tanks with a total storage capacity of 110 m³.
“We have been using MWM gas engines since 2012. So far, we have purchased 11 gen-sets from Caterpillar Energy Solutions in Mannheim with a total electrical output of about 17 MW for the modernization and operation of our cogeneration network for the district heat supply of Lübeck and the vicinity,” said Fred Schmeyers, head of Heat Supply at the municipal utility provider Stadtwerke Lübeck.
The regional energy supplier Stadtwerke Lübeck operates the city’s district heat network in different subnetworks. About €30 million have been invested in the development and modernization of decentralized cogeneration power plants and district heat lines. The district heat network comprises 14 combined heat and power plants and two more are planned.
The most recent project is the former air-raid shelter in St. Lorenz-Süd. Some of the special issues faced by the developers included the fact that the bunker is a graded building and its outer walls, which are made of bricks and reinforced concrete and have a thickness of 2.5 m, had to be penetrated to make room for the cogeneration power plant. Massive ceilings and walls had to be torn down, with huge challenges in statics.
Because of building conservation regulations, elements such as the visible wall edges, old safety paint, and bunker doors had to be preserved.
The 18-ton gen-set was shipped from Caterpillar Energy Solutions’ plant in Mannheim, Germany, with heavy good transport and rolled into the bunker on special load rollers.
Caterpillar Energy Solutions said the entire process from the planning to the completion of the cogeneration power plant in the bunker took about 18 months, especially because it was not easy to find a suitable place for a cogeneration power plant in the densely developed borough of St. Lorenz-Süd. The round bunker is a suitable location that is approved by the population and that combines the use and preservation of a historical structure with modern utilization for energy and heat supply.
“The MWM Service Center Berlin provides technical support. With full maintenance contracts for all cogeneration power plants, we ensure high availability of our gas gen-sets, whose average operating time amounts to 6500 hours a year,” Schmeyers said. “As we use the same gen-set types at all our cogeneration power plant sites, our engineers have even learned to perform minor maintenance and repair tasks themselves.”
A Siemens Megaproject For Egypt
The Beni Suef power plant is configured with four multi-shaft combined cycle plants SCC-8000-H 2X1, composed of eight SGT5-8000H gas turbines, four SST5-5000 steam turbines, and 12 SGen5-2000H.In March 2017, Siemens officially inaugurated phase one of the Siemens Magaproject in Egypt, with the opening of the Beni Suef power plant – the first of the three 4.8-GW turnkey combined cycle power plants (supplemented by 12 wind parks with approximately 600 wind turbines).
Siemens said it set a new worldwide benchmark for the execution of fast-track power projects. The promised goal of bringing 4.4 GW of new capacity to the grid has even been exceeded, and 4.8 GW were connected to the grid – only 18 months after signing the agreement. The 10% surplus capacity of 400 MW is sufficient to supply more than one million people in Egypt with electricity.
The Megaproject that Siemens is carrying out with its local partners Orascom Construction and Elsewedy Electric, is expected to boost Egypt’s power generation capacity by 45%, upon final completion of the planned three power plants.
The Beni Suef power plant is configured with four multi-shaft combined cycle plants SCC-8000-H 2X1, composed of eight SGT5-8000H gas turbines, four SST5-5000 steam turbines, and 12 SGen5-2000H. Cooling is provided by wet cell cooling towers and the overall control system is a Siemens SPPA-T3000. The plant utilizes natural gas as a fuel, with diesel as a backup.
The plant is positioned in Beni Suef governorate to serve the residential demand in Upper Egypt. It provides electricity to remote and rural villages as well as supplies the energy-intensive industries with electricity. Approximately 5 500 engineers, technicians and workers have been employed on site with a total more than 38 million man-hours (as of February 25, 2018) from the beginning of the project.
The other two plants in Burullus and New Capital will be identically designed. When completed, each of the plants is set to become the biggest gas-fired combined-cycle power station in the world, Siemens said.
Altogether, the three power plants will have a combined capacity of 14.4 GW. They will be powered by 24 Siemens H-Class gas turbines, selected for their high output and efficiency. The scope of supply also comprises twelve steam turbines, 36 generators, 24 heat recovery steam generators and three 500 kV gas-insulated switchgear systems.
The dimensions of the megaproject are enormous: more than 22 000 workers are engaged at the construction sites during implementation. Over 1.6 million tons of material have been imported. The megaproject is expected to bring power to 45 million people and enable Egypt to achieve US$ 1.3 billion in fuel savings on an annual basis.
As of January 2018, 22 out of the 24 Siemens gas turbines are in reliability run or already successfully completed. With a power output of 400 MW and a combined cycle efficiency of about 61%, the SGT5-8000H is among the most efficient and powerful gas turbines in commercial operation, with low operating and lifecycle costs.
With a focus on building local talent and capacity, Siemens is also training 600 Egyptian engineers and technicians, who will contribute to Egypt’s future of energy.