Salem Harbour Combined-Cycle Gas Turbine Power Plant, Massachusetts, United States of America

The Salem Harbour Station located 30km from Boston, Massachusetts, is being converted into a combined cycle power plant. The new natural gas-fired plant will have an installed capacity of 674MW.

It will consist of two units that will replace the four existing coal- and oil-fired units of the plant. The project is being undertaken by New Jersey-based firm Footprint Power, which specialises in transforming older and less efficient coal- and oil-fired facilities into more efficient power plants.

Construction of the power plant is scheduled to begin in the first half of 2015. Commissioning activities are expected to be underway by late 2016 and first steam production is scheduled for March 2017. Commercial operation is expected to begin in June 2017. An average of 320 construction jobs and a maximum of 600 jobs will be created during the construction phase.

The Salem Harbour CCGT plant is expected provide electricity to more than 600,000 homes and fill the power gap in the Northeastern Massachusetts (NEMA) and Boston region. It will offset approximately 450,000t of CO₂ emissions a year, on an average.

Salem Harbour Station history and redevelopment

The first unit of the Salem Harbour Station was commissioned in November 1951. Two more coal-fired units were added to the plant in the 1950s. An oil-fired unit 4 was commissioned in 1972 owing to the region's growing demand for electricity, bringing the total capacity of the power station to 745MW.

Footprint Power purchased the coal- and oil-fired power generation facility in August 2012 from Dominion, which was unable to keep up with the stringent pollution rules and high cost of operations.

Footprint Power cleared the ISO-NE Forward Capacity Auction to supply its electricity in February 2013 and the Energy Facilities Siting Board (EFSB) approved the company's petition to construct the new power plant in October 2013.

The 65 year-old Salem Harbour Station was decommissioned on 31 May 2014. Demolition of the existing four units, which will be replaced by two new state-of-the-art combined cycle units 5 and 6, began in July 2014.

Site details of the new CCGT plant

The new combined-cycle power plant will occupy 20 acres in the north-western portion of the existing 65-acre waterfront site. The remaining open areas will be developed to include a Harbourwalk, larger wharf, and expanded facilities for ferries, fishing vessels and cruise ships.

New Salem Harbour CCGT plant make-up

The quick-start plant will utilise General Electric (GE) FlexEfficiency 60 technology, which offers greater base load efficiency.

The units 5 and 6 will contain two GE 7F 5-series gas turbines with 'Rapid Response' capability, two steam turbines, and two heat recovery steam generators with selective catalytic reduction (SCR) and CO catalyst. They will be capable of adding 300MW of power to the grid within 10 minutes of start-up and convert 58% of the energy in gas into electrical power.

The units will be equipped with advanced emissions controls and noise reduction technology. They will turn down during off-peak hours, thus conserving fuel and reducing emissions output associated with a plant start-up.

The new plant is estimated to reduce the regional NOx emissions by 10%, SO2 emissions by 8%, and mercury emissions by 6%. The plant will utilise air-cooled condensers and avoid the use of large quantities of water from Salem Harbour for once-through cooling.

The facility will also include a water treatment facility, step-up transformers, two to three water tanks, and a 34,000gal above-ground ammonia storage tank used for the pollution control processes.

Gas supply to the Salem Harbour CCGT plant

Natural gas will be delivered from the Algonquin Gas Transmission pipeline system to the Salem Harbour facility through a new 1.2mi-long, 16in diameter pipeline owned and operated by Spectra Energy. Footprint will build a piping system to interconnect with the new pipeline and the on-site meter station for supplying the natural gas fuel to the gas turbines.

Transmission of electricity

Electricity generated from the plant will be fed to the national grid system at the existing substation located onsite.

Contractors involved

Footprint Power will construct a new switchyard facility and connect each of the four generator step-up transformers to it through 115kV underground cable connections. Two 700ft-long underground 115kV transmission lines will connect the new switchyard and the national grid substation.

Iberdrola Engineering was awarded a construction contract by Footprint Power in December 2014. The scope of work includes all engineering, procurement, construction, commissioning, and site works for the new facility. Iberdrola is also responsible for landscaping the open spaces upon completion of the construction.

Footprint Power signed a $200m contract with GE on 31 October 2013 for supplying the FlexEfficiency 60 technology. Cookfox Architects designed the environment-friendly building of the power plant. Spectra Energy is responsible for the construction of an on-site metering and regulator station at the facility.

TetraTech is providing environmental consulting and permitting services for the demolition and redevelopment of the power station. It conducted environmental investigations at the site, and is assisting with the site and civil design including site utilities plans, grading and drainage plans, and erosion and sedimentation control plans.

Race Bank Offshore Wind Farm, United Kingdom

The 580MW Race Bank is being developed by DONG Energy in the Greater Wash region, approximately 27km off the UK east coast. It will be one of the biggest offshore wind farms in the world when completed. DONG acquired the project from Centrica for £50m (approximately $81m) in December 2013.

The Crown Estate had awarded a 50 year lease to Centrica for building the Race Bank wind farm in 2004. The development consent for the project was awarded in 2012. Onshore construction is expected to begin in 2015, followed by offshore construction in 2016, while commercial operation is scheduled to begin in 2018.

With an estimated operational lifespan of 25 years, the Race Bank wind farm is expected to produce electricity sufficient to provide for more than 400,000 UK homes. It is further estimated to offset more than 830,000t of CO₂ emissions a year.

Race Bank offshore wind farm location and make-up

The offshore wind project will be located approximately 17m (27.3km) from Blakeney Point on the North Norfolk Coast, and approximately 17.4m from the Lincolnshire coast at Chapel St. Leonards. It will be approximately 32km off the British eastern coast and will extend over approximately 75km².

The wind farm will consist of 91 Siemens wind turbines of 6MW each. Each turbine will have a rotor diameter of 154m and be erected on monopile foundations in water depths ranging between 6m and 26m.

A2SEA's purpose-built offshore installation vessel Sea Challenger will be used to install the turbines.

Offshore and onshore substations at Race Bank

The wind farm will comprise three offshore substations and an onshore substation, which is expected to be completed in 2016.

Alstom Grid's DS Agile technology, a next-generation digital control system for smart substations, will be installed at the project. The DS Agile system will include advanced situational awareness features and MiCOM P40 Agile protection system, which enables to protect, monitor and control the assets.

The onshore substation will be located adjacent to the Walpole Substation and will consist of all the equipment to transmit power from the offshore substation to the national grid network.

Transmission of electricity generated by Race Bank

The electricity generated by the wind farm is proposed to be delivered to the onshore substation by using export cables. The cables are proposed to have a landfall east of the Nene River and approximately 3.7m (5.95km) north-north-east of Sutton Bridge.

Cables will be buried onshore for 6.8m (11km) from the landfall point to a new substation extension located directly adjacent to the existing substation at Walpole, Norfolk.

Contractors involved with the offshore wind project

JDR, a company based in the UK, will supply the subsea power cables. Its contractual scope includes the design and manufacture of 110km of 36kV inter-array cables, and accessories including hang-offs, electrical T-connectors, and cable cleats.Siemens Wind Power was awarded the contract for the supply, erection and servicing of the wind turbines.

J Murphy & Sons was awarded a £21.8m ($34m approximately) contract for the construction of the onshore substation. WSP will provide civil design support for the same.

Jan De Nul Group was engaged for installation of subsea export cables from the landfall to two offshore platforms, and that of the interlink between the offshore substations.

The contract for supply of 91 transition pieces for the wind farm was awarded to Bilfinger Mars Offshore (BMO). DONG Energy engaged Atkins to provide detailed substation design for the project.

NKT Cables was contracted for the supply of more than 150km of 220kV high-voltage export cable systems. The submarine cables are proposed to be delivered in 2017 in three phases.

Alstom was awarded the substation automation contract, while Seaway Heavy Lifting was contracted for the offshore substation transportation and installation. Dalcour Maclaren was appointed to advice on land rights in relation to the wind farm.

Polk Power Station Expansion, Florida, United States of America

Tampa Electric's Polk Power Station is further further expanded to convert four existing simple-cycle combustion turbine units into an integrated combined-cycle unit. The expansion will increase the station's generating capacity by an additional 460MW.

Construction works on the expansion started in January 2014 and are scheduled for completion in early-2017, at an estimated investment of $700m.

The expansion project will enable the power station to serve approximately 100,000 households and generate 500 local jobs during the peak construction phase. The expansion will meet the future power demands in the area and enable Tampa Electric to replace the existing power purchase agreements, which are due to expire.

Polk power station details

The power station, covering an area of about 4,300 acres, is located on State Road 37 in Polk County, approximately 13 miles (21km)south-west of the city of Bartow, Florida.

The plant has five units, which include a 260MW Unit I that started commercial operation in late-1996, two 180MW units (II and III) that came online in July 2000 and May 2002 respectively, and two 160MW units (IV and V) that came online in April 2007.

Unit I is an integrated coal gasification combined-cycle (IGCC) facility, the first of its kind in the country, while the other units are simple-cycle combustion turbine units. The units currently serve approximately 75,000 homes in total.

Expansion of the Polk power station

The Polk power station project will primarily involve the installation of four heat recovery steam generators (HRSGs) equipped with natural gas-fired duct burners, a steam turbine generator (STG), a six-cell mechanical draft cooling tower and an emergency diesel engine generator. The new facilities will complement the existing facilities.

The HRSGs will recover waste heat from the existing combustion turbine generators (CTGs) to produce steam, which will be conveyed to the new Alstom STF60C steam turbine and Gigatop generator to produce the additional electrical power.

The power station development also involves the construction of 40 miles (approximately 64km) of new transmission lines and upgrade of the existing transmission facilities to convey the additional output to the grid. The auxiliary cooling systems of the existing Unit 1 will also be upgraded to use the new cooling tower in place of the existing cooling reservoir.

The converted units will use natural gas as primary fuel and ultra-low-sulphur diesel (ULSD) as back-up fuel. The project will also introduce the selective catalytic reduction (SCR) technology at the site, which will reduce nitrogen oxide emissions from the existing units by more than 75%. The new facilities are expected to overall increase the efficiency of the existing units by 37%.

Recent innovations at Polk power station

A carbon dioxide capture and sequestration demonstration project at the site, implemented by Tempa Electric in collaboration with Research Triangle Institute International, was commissioned in April 2014. The project was implemented with a DOE Federal grant of approximately $168m.

The developed Polk plant will demonstrate RTI's warm-synthesis gas (syngas) cleanup technology during a one-year demonstration period. It is expected to capture 300,000t of CO² from the existing IGCC unit and sequester it more than 5,000ft below the power station in a saline formation.

The reclaimed water project was completed in April 2015 through the collaborative effort of Tampa Electric, Southwest Florida Water Management District and the city of Lakeland.

The $120m project involved the construction of a reclaimed-water pumping station and a 15 miles (approximately 24km) pipeline between the city of Lakeland's wetland treatment system and the power station, a reverse osmosis water-treatment system at the power plant's site and two deep-injection wells, located more than 1.5 miles underground on the power plant site.

The facility reclaims waste-water from the city of Lakeland and serves as cooling water at the Polk power station, after being treated. Additional phases of the project to reclaim the wastewater from the cities of Polk County and Mulberry are expected to come online by 2017.

Contractors involved with Polk Power Station expansion

The HRSGs for the project were manufactured in South Korea. The parties involved in the transportation of the HRSGs to the project site include Babcock Power, Port Manatee, BBC Chartering, Federal Marine Terminals and Beyel Brothers Crane & Rigging.The construction contractor for the expansion project is Robins & Morton, while the engineering partner to the developer is Black & Veatch.

Port Everglades Next Generation Clean Energy Centre, Florida, United States of America

Florida Power and Light Company (FPL) is developing the new 1,250MW Port Everglades Next Generation Clean Energy Centre (PEEC) to replace the existing Port Everglades power plant of the 1960s.

FPL demolished the Port Everglades power plant in 2013 and plans to begin construction of the new $1bn combined-cycle power plant in the second quarter of 2014. The new facility is expected to commence operations in 2016 and is estimated to produce clean electricity to provide for approximately 260,000 homes and businesses.

PEEC is expected to have an operational life period of 30 years, and is expected to create 650 direct and 1,000 indirect jobs during construction, and generate approximately $20m as tax revenue for the local government during its first year of operation.

PEEC location and make-up

Port Everglades power plant located near Fort Lauderdale in Broward County, Florida, was demolished using approximately 450lb of explosives. Dynamite charges were used for blasting the stacks while explosive charges were used for blasting the steel boilers.PEEC will feature a natural gas-fired combined cycle unit and other ancillary equipment. Natural gas will be used as primary fuel while ultralow sulphur distillate fuel oil will be used as backup fuel.

The plant will feature three 250MW combustion turbine generators equipped with evaporative inlet cooling system, a 500MW steam turbine generator, three heat recovery steam generators (HRSG) with selective catalytic reduction reactors and three 149ft exhaust stacks.

The combustion turbine generator (CTG) will comprise a continuous emission monitoring system (CEMS) for holding the NOx emissions in accordance with acid rain provisions. Each combustion turbine generator will fire natural gas with a maximum sulphur content of 2.0 grains per 100scf.

Ancillary equipment will include two temporary boilers to be used during construction, two emergency generators, a diesel fire pump, two process heaters and a gas compression station.

Power generation at PEEC

The combustion turbine generator, which is an internal combustion engine operating in a rotary rather, is coupled with an electrical generator. Ambient air will be compressed in the multi-stage compressor unit of the CTG. The compressed air will be directed to the combustor section, comprising individual steam-cooled Dry Low NOx (DLN) combustors, where fuel will be introduced, ignited and burned.

Hot combustion gases will be routed through the steam-cooled transition pieces and diluted with additional cool air from the compressor before transporting to the turbine (expansion) section.

In the turbine section, energy will be recovered in the form of shaft horsepower, most of which is required to drive the internal compressor section. The remaining recovered shaft energy will be used to drive the external load units, such as the electrical generator.

Turbine exhaust gas released at a temperature of more than 1,125ºF from the CTG units will be used to produce steam in the heat recovery steam generator. The generated steam will be used to drive the steam turbine for producing electrical power.

Turbine technology at the plant

PEEC will be equipped with SGT6-8000H gas turbine (H-Class) provided by Siemens. The turbine has a gross power output of 274MW, operates at a maximum speed of 3,600rpm and has a thermal efficiency of approximately 60%.

The turbine will have a faster start-up and cycling capability for supporting intermediate to continuous duty operation.The H-class gas turbine is internally air-cooled and equipped with enhanced sealing system for minimising the cooling air loss. The attached active turbine clearance control system will reduce the engine performance losses occurring during the operations phase.

Contractors involved with the project

Zachry Engineering was awarded the engineering, procurement and construction (EPC) contract for the project. Siemens was awarded the contract for supplying H-class gas turbines for the new energy centre.

Post Rock Wind Farm, Kansas, United States of America

The 201MW Post Rock Wind Farm is located in Ellsworth and Lincoln counties of Kansas, US. Wind Capital Group, a US-based subsidiary of Irish renewable energy firm NTR, is the owner and developer of the wind power project.

The construction of the $375m Post Rock Wind Farm started in September 2011 and was completed by October 2012. The wind farm was officially inaugurated in November 2012.

In December 2012, GE Energy Financial Services teamed up with MetLife and Union Bank to buy a stake in the wind farm for $247m. Wind Capital Group still retains substantial equity and is the managing member of the project.

The wind farm has the potential to serve electricity needs of 70,000 households while offsetting 815,000t of greenhouse gas emissions a year.

Post Rock Wind Farm development

In December 2010, a 20-year Power Purchase Agreement was signed with Kansas-based electric utility Westar Energy, which will buy electricity from Post Rock Wind Farm.The Post Rock Wind Project was originally undertaken by Hilliard Energy. The project was later acquired by the Wind Capital Group, which is focused on wind energy business opportunities in the US.

The Engineering Procurement and Construction (EPC) contract for the wind energy project was awarded in May 2011. Construction works began in late 2011 and took one year to complete. The project created 150 jobs during construction.

Financing Wind Capital Group's project

The financing for Post Rock Wind Farm was completed in January 2012. The project was entirely financed through a debt of more than $350m, which was provided by a group of international lenders, including BayernLB, Rabobank, Nord LB and Union Bank. It comprised of a construction loan worth $293m, an in term loan of $63m and a $20m letter of credit facility.

GE turbines for Kansas's energy project

Post Rock Wind Farm spreads across an area of 23,000 acres (9,307ha) in Ellsworth and Lincoln counties of Kansas. The project site is located 80 miles (128.7km) away from Wichita, the largest city of Kansas.

Post Rock Wind Farm consists of 134 three-bladed GE wind turbines, each one with a rated output of 1.5MW. The height of the turbines is around 300ft and the blade length is 37m.

Power generated by each turbine is transferred to a 34.5kV underground collector system that runs 24.6 miles (39.5km) in length. It is then stepped up at the 34.5/230kV substation.The rotor diameter of each turbine is 82.5m. The rotor speed is guided by electric drive pitch control with battery backup. The turbines are also equipped with aerodynamic braking systems. The turbine towers are mounted on spread-footing foundations and are equipped with in-tower wiring.

The wind farm is interconnected with a substation in Rice County, via a new 31mi (49.8km) long 230kV transmission line passing through Ellsworth, Lincoln and Rice counties. The wind farm also features two meteorological towers.

Contractors involved with the Post Rock wind project

RMT was chosen as the EPC contractor for the civil and electrical infrastructure of the Post Rock wind project. The scope of the contract included construction of 19.6 miles of access roads, turbine foundations, tower erection and the associated electrical infrastructure, including the in-tower wiring, underground cabling, the step-up substation and the new transmission line.

General Electric supplied the wind turbines for the project. It will also provide operation and maintenance services for the wind farm.

EnBW Baltic 2 Offshore Wind Farm, Germany

The EnBW Baltic 2 offshore wind farm is a 288MW project developed in the German waters of Baltic Sea. Formerly known as Kriegers Flak, the wind farm is EnBW Energie Baden-Württemberg's second project in the German Baltic Sea after the Baltic 1 offshore wind farm, which was commissioned in 2010.

Construction of one of the world's biggest offshore wind farms started with the laying of foundation in August 2013. The first turbine was erected in August 2014 and first electricity was fed into the grid in April 2015. The wind farm was officially put into operation in September 2015.

It is expected to generate 1.2TWh of electricity a year, sufficient to supply for approximately 340,000 households. It is estimated to reduce 900,000t of CO2 emissions a year from the atmosphere. The Baltic 2 wind farm is four times bigger and produces six times more electricity as its predecessor.

EnBW Baltic 2 offshore wind farm location and make-up

The Baltic 2 wind farm is located 32km north of Rügen Island in the western Baltic Sea. Spread across approximately 2.7 million hectares, the wind farm is four times bigger and produces six times more electricity compared with its predecessor, the Baltic 1 wind farm.

The new wind farm consists of 80 Siemens SWT-3.6 wind turbines, with a capacity of 3.6MW each, installed on monopile foundations at water depths between 25m and 35m. The turbine has a rotor diameter of 120m and a hub height of 78.25m.

The turbine foundations are installed between 36m and 55m into the seabed. Approximately 80,000t of steel was used for the foundations. The steel tower is 66m-tall and weighs approximately 256t.

The wind turbines were delivered using the Esvagt Froude offshore service fleet. The turbine components were produced at a number of sites in Denmark and delivered to base port Sassnitz Mukran for further delivery to the plant site. The steel towers, nacelle and rotor blades were stored and preassembled up to three months prior to the start of installation.

The wind farm is controlled and maintained from the control room in Barhöft.

Ownership and financing of Baltic 2 wind farm

European Investment Bank (EIB) granted a €500m loan to EnBW in January 2013 to develop the Baltic 2 offshore wind farm.German power utility EnBW Energie Baden-Württemberg holds a 50.11% stake in the project, while the remaining is held by PGGM. Macquarie Capital acquired a 49.89% interest in the wind farm on 8 January 2015, for €720m (approximately $799m), and sold it to PGGM in June 2015.

Offshore substation and electricity distribution

The offshore substation consists of a 155/33kV transformer, 170kV and 33kV GIS switchyard, protection and control equipment, emergency diesel generators and other major equipment.

The floating substation platform is 40m x 40m, 15m-tall, and weighs approximately 2,650t. Electricity generated by the wind turbines is collected at the substation and the voltage is enhanced from 33kV to 150kV for export.

The wind farm substation is connected to the Baltic 1 offshore platform by a special export cable in order to transmit electricity to the high-voltage grid at Bentwisch (near Rostock).

Contractors involved with the Baltic 2 offshore wind farm development

EnBW awarded the contract for the supply of 80 wind turbines for the Baltic 2 wind farm to Siemens in June 2010. Siemens subcontracted MADESTA for manufacturing and supplying wind tower door frames for the project.

Transmission system operator 50Hertz was responsible for the offshore grid connections in the German Baltic Sea and awarded the contract for monitoring the submarine power cables to Nkt cables.

Alstom was contracted for the installation, erection and commissioning of a self-floating, self-installing offshore substation platform for the Baltic 2 wind farm.

Bladt Industries was awarded the contract for conducting fabrication works for the jacket foundations. The joint-venture of VBMS-Boka was engaged for installing the 57km-long, 150kV export cables.

The joint-venture of HOCHTIEF Construction and Nordsee-GeoSea (DEME) was contracted to assemble major elements of the Baltic 2 wind farm. The joint venture was responsible for the delivery and erection of foundations, and logistics for the construction of the towers and the wind turbines.

General Cable was subcontracted by 50Hertz for designing, manufacturing, supplying and installing two 60km sections of 150kV high-voltage export submarine cables, three single cores of underground terrestrial transmission cables and associated accessories for Baltic 2.

FRS Windcat Offshore Logistics (FWOL) was awarded a five-year contract to provide a Windcat 34-crew transport vessel for transporting crew daily from Rostock town to the wind farm.

In March 2013, Ballast Nedam was awarded a contract for erecting monopile and transition piece foundations as well as providing logistics between the feeder ports in Rostock, Lubmin, and the Baltic 2 offshore wind farm.

Siem Offshore Contractors (SOC), a wholly owned subsidiary of Siem Offshore, was awarded the contract for the installation of the inner array grid cables. SOC engaged JDR for providing pre-commissioning, test and termination services for the project.

ESG supplied a portable cable tank for the replacement cable at the offshore wind farm, while WINDEA Offshore was engaged to provide maritime coordination services.

Ashurst advised Macquarie Capital regarding the acquisition and financing of the Baltic 2 wind farm.

Desert Sunlight Solar Farm, Riverside County, California, United States of America

Desert Sunlight Solar Farm is a 550MW photovoltaic (PV) solar power project built across 3,600 acres land in the Chuckwalla Valley. It was developed by NextEra Energy Resources and GE Financial Services. It is located in the east of Riverside County of California over land managed by the US Bureau of Land Management (BLM).

It is capable of generating enough clean energy to serve around 160,000 California homes and displaces 300,000mt of carbon dioxide emissions annually. It is expected to support the state in achieving 33% of power from renewable resources by 2020.The project witnessed the start of construction in September 2011 and was commissioned in February 2015.

Pacific Gas & Electric (PG&E) Company purchases the power generated in the first phase whileSouthern California Edison purchases the power generated in the second phase, under two separate long-term power purchase agreements (PPA).

Solar farm composition and development phases

The transmission infrastructure is built across 230 acres and the new Red Bluff substation is built on a 90-acre site. The substation is owned and operated by Southern California Edison.

The solar farm project was developed in two phases. The first phase has an installed capacity of 300MW and the second phase is of 250MW, adding up to a total generating capacity of 550MW.The solar farm employs approximately 8.8 million cadmium telluride thin-film photovoltaic (PV) modules. The PV modules are installed at less than 6ft in height above the ground, causing low visual impact. The project uses around 70,000t of American steel.

Construction approval and EPC contract

The project got final approval from the Department of Interior Secretary Ken Salazar in August 2011 and construction was started immediately.

First Solar was awarded an engineering, procurement and construction (EPC) contract for the construction of the Desert Sunlight solar project.

Under the EPC contract, First Solar provided the thin-film photovoltaic (PV) modules and EPC services. The company will operate and maintain the solar farm for 25 years under a separate agreement.

First Solar manufactured the PV modules at its Mesa facility. The overall contract execution required approximately 440 construction workers on an average.

Desert Sunlight project network connection

The Desert Sunlight solar farm is connected to the Red Bluff Substation by a 230kV interconnection transmission line. The Red Bluff substation supplies the output power to the national grid through Southern California Edison's Devers-Palo Verde 1 transmission line.

The US Department of Energy approved $1.88bn in partial loan guarantees for the project in September 2011.

Local environmental impact in Riverside County

The Interior's Bureau of Land Management (BLM) along with the National Park Services and stake holders closely observed the project in order to reduce the proposed land used for the solar farm. The project was environmentally analysed and reviewed. The final environmental review report was released on 15 April 2011.

The BLM was concerned about desert tortoise habitat and other wildlife species that would be affected due to the project. The environmental impact study proposed plans for the translocation of the tortoises and compensating the habitants that would be affected by the project.

Davis-Besse Nuclear Power Station, Ohio, United States of America

The 894MW Davis-Besse Nuclear Power Station produces approximately 40% of the total power consumed by the north-western region of Ohio state.

It is located on the south-east shore of Lake Erie, about 16km north of Oak Harbor, Ohio.

Construction of the facility began in 1970 and grid connection was achieved in 1977, with commercial operations starting in July 1978.

Cleveland Electric owns 51.4% stake in the plant, while Toledo Edison holds the remaining 48.6%. FirstEnergy Nuclear Operating Company (FENOC), a subsidiary of FirstEnergy Nuclear operates the plant. The operating license is scheduled to expire in April 2017 and FENOC is in the process of renewing it.

The power station will be shut down from January 2014 as part of a refuelling and maintenance outage. FENOC will install two new steam generators and conduct refuelling and other scheduled maintenance works at the plant. The generators will function as heat exchangers producing the super heated steam required for electricity production.

Equipment at Davis-Besse nuclear power plant

The Davis-Besse NPP comprises of an 894MW (gross capacity 925MW) raised loop type Pressurised Water Reactor (PWR). It includes a pressuriser, reactor coolant pump, steel containment structure, steam generators, control rod drive mechanism, and an emergency core cooling system.

The reactor was designed based on 'Defence-in-depth' concept, which involves the installation of barriers between the radioactive heat-producing core and the outside environment. It comprises three major equipments: reactor core, carbon steel vessel, and steel containment structure.

The reactor core helps in retaining the radioactive material in uranium oxide and is placed within a six-inch thick carbon steel vessel. The vessel contains highly pressurised water to cool the radioactive heat-producing core.

The reactor vessel and other components are enclosed within a steel containment in a concrete building. The set up prevents the release of radioactive material and protects the reactor from external hazards.

The pressuriser contains heaters for raising the water temperature within the reactor, and water sprays for condensing the steam volume and lowering pressure. The hot pressurised water is transferred to the steam generator via pipes, which is converted into steam to drive the turbines for generating electricity.

Major incidents at the Ohio nuclear power plant

In March 2002 an erosion of six-inch thickness on the carbon steel reactor was identified, which caused the leakage of borated water. If not identified, the leakage would have created a mass loss-of-coolant accident, and would have damaged the control rod drive mechanism. The plant was re-opened in 2004 after fulfilling the NRC's safety measures.A disruption in the feed water system caused the shutdown of the plant for the first time in September 1977. It resulted in the opening of a pressuriser valve, which the US Nuclear Regulatory Commission (NRC) as one of the most serious nuclear accidents of those times.

Cracks were identified on 24 of the 69 control rod drive nozzles during a refuelling outage in March 2010, which could have led to leakage of boric acid. Operations at the plant were restarted in 2010, after repairing the nozzles.

The most recent temporary shutdown at the plant occurred in October 2011 upon identification of a major hairline crack on the concrete shield building around the containment vessel.

Contractors involved with Davis-Besse nuclear facility

Babcock and Wilcox were contracted to manufacture two new 74ft tall steam generators for the nuclear power station. The generators were manufactured at the company's Cambridge facility and shipped through Lake Erie. Final delivery was made in October 2013. The same company had supplied the 879MW pressurised water reactor to the power plant.

Bechtel was awarded the engineering, procurement and construction (EPC) services contract in October 2009, to replace the steam generators and the reactor pressure vessel closure head.

Cape Wind Project, Massachusetts, United States of America

Cape Wind will be the first utility scale offshore wind farm to be developed in the US. The 468MW wind power project located in federal waters off the coast of Cape Cod, Massachusetts, on Horseshoe Shoal in Nantucket Sound will feature 130 wind turbines with 3.6MW capacity each.

The $2.6bn offshore wind farm is being developed by Massachusetts-based energy company Energy Management Inc (EMI). Construction on the ocean front is expected to begin in 2015 and production is expected to commence in 2016.

The wind farm will produce enough energy to power more than 420,000 homes.

Cape Wind project development

As the first offshore wind power development in the US, the project experienced a prolonged development and permitting process. Application for commercial lease of the offshore wind project was made to US Department of Interior in September 2005. The department permitted a 25 year commercial lease in April 2010 after the project's final environmental impact statement (EIS) was published in January 2009.

The project construction and operation plan (COP) was submitted in October 2010 and was finally approved by US Bureau of Ocean Energy Management (BOEM) in September 2014.

Cape wind farm make-up and turbine details

Cape Wind will comprise of 130 SWT-3.6-107 wind turbines from Siemens, arrayed in parallel rows in shallow waters. The turbines in each row will be 630m apart, while the rows will be approximately 1km apart from each other.

Each three-bladed and horizontal axis turbine, mounted on a tapered tubular steel tower with a 16ft base diameter will have a rotor diameter of 107m and blade length of 52m. The pitch-regulated variable speed wind turbine will provide rotor speed of up to 16 revolutions per minute (RPM), while offering a swept area of 9,000m². The cut-in and cut-out wind speeds of the turbine are 5m a second (m/s) and 25m/s respectively.

The height of the turbine towers from water surface to the blade centre will be 258ft, whereas the lowest and highest blade tip heights from the water surface will be 75ft and 440ft respectively.

Power generated by the turbines will be transferred via intra array submarine cables to the Electric Service Platform (ESP) located near the centre of the wind farm, and further transmitted to the shore.

The operations headquarters of the project is planned to be constructed along Falmouth Harbour on Cape Cod.

Construction

The offshore wind turbines will be installed by a fleet of vessels including the R D MacDonald, the first special purpose offshore wind installation vessel built in the US.The turbines will be supported by monopole foundations driven deep into the seabed, and the towers will be bolted onto the foundations after fixing the transition pieces to the monopiles. Intra array submarine cables will be jet ploughed six feet into the seabed.

Cape Wind project financing

Cape Wind raised $1.3bn for the offshore wind project as of April 2014. The US Department of Energy (DOE) issued a conditional commitment for a $150m loan guarantee for the project.

A consortium comprised of Bank of Tokyo-Mitsubishi UFJ, Natixis and Rabobank are providing more than $400m in commercial debt for the project. A mezzanine debt of $200m will be provided by PensionDanmark, while a $600m funding commitment has been made by the Export Bank of Denmark (EKF).

Barclays Bank is the financial advisor for Cape Wind.

Power transmission and purchase from Cape Wind

The electric service platform (ESP) of the wind farm will work as an offshore substation, where the electricity will be transmitted via two 12.5 mile long submarine cables that will make landfall in New Hampshire Avenue in West Yarmouth. From the landfall site, the electricity will be transmitted via underground cables to the electric grid at Barnstable substation.

National Grid and NSTAR, two leading Massachusetts-based utilities, will respectively purchase 50% and 27.5% of the wind farm's output under two separate 15 year power purchase agreements.

Contractors involved

A consortium consisting of Ramboll, Keystone Engineering and PMSS was chosen for the detailed design of the steel monopile foundations in May 2012. K2 Management has been serving as theproject manager for Cape Wind since 2011.A joint venture of Weeks Marine and Manson Construction was selected as the lead construction contractor for the offshore wind project in August 2014. The Boston and New England Maritime Trades Council and the American Federation of Labor and Congress of Industrial Organizations (AFL -CIO) will supply a skilled work force for the joint venture.

Siemens was awarded the contract to supply the wind turbines and the ESP for the offshore wind project in December 2013. The company is responsible for the fabrication, installation and commissioning of the turbines. The scope of the contract includes a 15 -ear maintenance agreement for the wind turbines and the ESP.

Siemens subcontracted the manufacturing of ESP to Cianbro. Moffatt and Nichol Engineers designed the ESP for Cianbro.

Tekmar, a UK-based company was contracted in June 2014 to provide more than 200 of its TekLink cable protection systems (CPS) for the project's inter array and export cables. Tekmar is also supplying bellmouth and cable guide cones as part of the contract.

Prysmian Cables and Systems USA were contracted in March 2014 for the supply of intra array and export power cables and, Caldwell Marine International were contracted for installing the underwater cables.

Lawrence-Lynch Corp is responsible for the upland construction work required for burying the electric cables. The company will also provide a channel for connecting the on-land electric cables with the submerged ocean submarine cable using directional drilling.

The geophysical and geotechnical survey team for the project was led by Fugro. ESS group was the lead environmental consultant, who also prepared the construction and operations plan (COP) for the project.

Cape Scott Wind Farm, Vancouver Island, British Columbia, Canada

The 99MW Cape Scott wind farm is situated approximately 35km to the west of Port Hardy in Vancouver Island, British Columbia. Formerly known as Knob Hill wind farm, it is the first utility-scale project to be developed on the western coast of British Columbia.

The C$325m (approximately $290m) project is owned, developed and operated by GDF SUEZ Canada, Mitsui and Fiera Axium. GDF SUEZ Canada, a subsidiary of GDF SUEZ, holds a 40% stake, while the other two companies hold 30% each.Construction began in 2011, with commercial operations starting in November 2013. The project generated approximately 150 construction jobs and 12 permanent operations and maintenance positions. It is expected to annually generate 290GWh of clean energy, enough to power 30,000 Vancouver Island homes.

Cape Scott wind farm history, location and make-up

Sea Breeze Power had initiated the Cape Scott project under the name Knob Hill, and conducted the site identification and obtained all the required permits before selling it to International Power, a fully-owned subsidiary of GDF SUEZ. Sea Breeze is entitled to a quarterly royalty payment of 1% of gross revenue generated.

The wind farm extends over 864 acres (350ha) outside of Cape Scott National Park and comprises 55 Vestas V100 1.8MW turbines. The turbine tower is made of tubular steel and has a hub height of 80m. Each turbine has three blades measuring 49m long, while the rotor diameter is 100m and swept area is 7,854m².Located on the Knob Hill Plateau, on the northernmost region of Vancouver Island, it is the first wind energy project to be approved by the Environmental Assessment Office of British Columbia. An expansion to add 50MW capacity is also planned.

Construction of the wind farm

Early works mainly focused on clearing the land for roads and other civil construction works, with construction consisting of a concrete batch plant, site access roads, turbine and substation foundations, installation of the concrete batch plant, and the turbines. A 40km-long transmission line for connecting the facility to the grid was also built.

Approximately 33km of site access roads were constructed as part of the project.

Transmission and sale of the generated power

The power generated by the wind farm is transmitted to the Port Hardy Substation via a 132kV transmission line, with BC Hydro purchasing this under a 20-year power purchase agreement signed in March 2010.

Financing for the Canadian wind farm

The Cape Scott wind farm was financed by Japan Bank for International Cooperation and a group of commercial banks comprising The Bank of Tokyo-Mitsubishi, Mizuho Corporate Bank and Sumitomo Mitsui Banking Corporation.

Contractors involved with the project

The engineering, procurement and construction (EPC) contract was awarded to the joint venture (JV) of AMEC and Black & McDonald. The contractual scope included an upgrade of the existing forest roads, construction of site access roads, transmission line, and laying the turbine foundations. The JV also installed the electrical collector system and switchyard, and conducted the turbine erection and commissioning.

Amix Heavylifts received the contract to conduct shore offloading of the wind turbine tower components at the Duke Point facility, while Mega Cranes supplied 240t Liebherr cranes for offloading and delivering the windmill components to the site.

Surespan handled the construction of roads, installation of corrugated steel pipes and fish culverts, supply and installation of bridge structures, and supply and delivery of ready mixed concrete.

Callide Coal-Fired Power Stations, Queensland, Australia

Callide power station is located in the Callide Valley, 18km east of Biloela in central Queensland, Australia. The Callide site has three power stations, namely Callide A, Callide B and Callide C.

Callide B and C are now on line, generating enough power for nearly two million homes. Callide A is in storage, with the fourth unit being retrofitted for the Callide Oxyfuel Project, a clean coal demonstration project.

Callide A and B are 100% owned by CS Energy Ltd. Callide C is a 50/50 joint venture between CS Energy and InterGen.

Callide B and C operate as base load stations with nearly 200 people working on the site full time. The power station uses about six million tonnes of black coal a year, conveyed from the nearby Callide Mine.

Callide A details (intended for oxyfuel project)

Steam temperature was designed at 460ºC and pressure at 4300kPa. Callide A is the world's largest remote controlled coal-fired power station.Originally built in 1965, the 120MW Callide A has four 30MW units designed to supply power at 132kV. The turbine was supplied by Parsons, and the boiler by Mitchell Engineering.

It was refurbished in 1998 and is presently in storage. CS Energy is partnering with five other organisations on an A$206m clean coal demonstration project. The project will retrofit oxyfuel technology to one of the Callide A boilers.

That involves burning of pulverised coal in a boiler with a mixture of oxygen and recirculated waste gases to create a high concentration of CO2 in the gases exiting the boiler.

The CO2 will then be captured, purified and compressed to liquid form. The liquefied CO2 is ready for transport to an underground storage site for geosequestration. Suitable sites are sedimentary basins that have permeable rock to absorb the CO2, with a natural upper seal of non-permeable rock.

Depleted gas fields have high CO2 storage potential, as they have characteristics that enabled natural gases to be stored there for millions of years.

The Callide Oxyfuel Project team selected Denison Trough for the storage of carbon dioxide after extensive studies.

Work on the clean demonstration plant, Callide Oxyfuel Project, began in November 2008 and the demonstration commenced in 2013.

The project, which is a joint venture between CS Energy, the Australian Coal Association, Xstrata Coal, Schlumberger, JPower, Mitsui and IHI Corporation, has received financial support from the governments of Australia, Queensland and Japan.

Callide B and C power stations (generating 1600MW)

Callide B generates 700MW from two 350MW units and was commissioned in 1988. The turbine came from Hitachi and the boiler from Babcock Hitachi. Steam temperatures and pressures are higher than for Callide A, at 539ºC and 17700kPa.

The 900MW Callide Power Plant (Callide C) was commissioned in 2001 at a cost of A$800m. Callide C has two 450MW units and, like Callide B, generates power at 275kV. Toshiba supplied the advanced cycle steam turbine, and IHI the boiler.Callide B, in the past, has operated continuously for 477 days, creating a record for the longest operation.

Steam temperatures and pressures were raised again over Callide B, to 566ºC and 25,100kPa. It is managed by Callide Power Management, a joint venture company.

Callide C was the first power station in Australia to use supercritical boilers, which have higher thermal efficiencies than conventional coal-fired technology. Callide C uses coal from the nearby Anglo Coal Callide Mine, and draws water from Awoonga Dam near Gladstone.

Callide C has consistently achieved 94% availability since the most recent big outage in mid-2006. The unit's environmental controls include real-time emissions monitoring with operator alarms and self-tuning capabilities within the control system.

Baghouse filters remove fly ash and low nitrogen oxide burners further reduce emissions of oxides of nitrogen.

Three Queensland power stations

CS Energy is an Australian power company that owns and operates three power stations in Queensland, generating almost 3,000MW in total. The company participates in the national electricity market, and is the main electricity generator for the remote regional market in Queensland's North West Minerals Province.

CS Energy was established on 1 July 1997 following the restructuring of the Queensland electricity supply industry.

In a joint venture with CS Energy, Callide C has augmented the Callide water supply by developing the Stag Creek Pipeline project. The project was completed in November 2005. It reduces the diversion of water from nearby Awoonga Dam and increases community water allocations.

California Valley Solar Ranch, United States of America

California Valley Solar Ranch (CVSR) is a 250MW solar photovoltaic (PV) power project developed in San Luis Obispo County, California, US. Construction of the project started in September 2011 and full commercial operations began in October 2013.

NRG Energy (NRG) became the sole owner of the plant after NRG Solar, a wholly owned subsidiary of NRG, acquired the project from SunPower in September 2011. Total investment on the project is estimated to be approximately $1.6bn.

The power generated by the project will be enough to meet the annual electricity needs of as many as 100,000 homes on average.

California Valley Solar Ranch site details

The project is spread over approximately 4,700 acres (1,902ha) of former grazing land in the Carrizo Plain. Solar arrays, substation and facility buildings cover just 30% of the project site, while the remaining land is preserved and used for the conservation of species in the area.

The site also includes an abandoned gypsum mine, which was cleaned and restored for operations.

The location was selected because of its flat topography, abundant solar resources and proximity to existing transmission lines.

CVSR plant makeup

The Oasis power plant uses high-density 1.5MW solar power blocks, which are fast, cost-effective and significantly reduce land usage. A total of 749,088 solar panels are installed at the plant.The primary elements of the project include ten solar PV arrays, electrical equipment, generation tie-line, substation and switchyard, and transmission lines. The solar PV arrays use SunPower's Oasis power plant technology, which comprises a SunPower T0 tracker, Oasis Inverter, pre-engineered Direct Current (DC) collection system, a Tracker Monitoring and Control System (TMAC), and a Supervisory Control and Data Acquisition (SCADA) system.

Trackers are installed on low-impact metal pier foundations, which are directly driven into the ground, eliminating the need for concrete foundations. TMAC controls predict weather conditions effectively thus increasing operating efficiency and reducing maintenance costs.

Power supply from the CVSR facility

The power from the solar facility is purchased by Pacific Gas & Electric (PG&E) under a 25-year power purchase agreement. The generated electricity is transferred to the Morro Bay-Midway transmission line through a tie-line and switchyard.

Contractors and financiers involved with the CVSR project

NRG and SunPower are responsible for the operations and maintenance of the plant for the first two years, after which NRG will solely take over these activities.SunPower was responsible for the design and construction of the plant. Betchel was appointed as the engineering, procurement and construction (EPC) contractor.

The project received a $1.23bn loan guarantee from the US Department of Energy's (DOE) Loan Programs Office in September 2011.

Environmental and economic benefits of the CVSR project

The CVSR facility is a source of clean and quiet renewable energy. It requires minimal water for periodic cleanups and includes a water recycling plant. It will reduce harmful gaseous emissions by approximately 336,000t annually.

SunPower solar panels are designed for safe recycling at the end of their useful life, which is more than 25 years. The panels do not contain any hazardous material, galvanised metal or lead solder.

The 12,000 acre area in and around the Carrizo Plain is protected, restored and managed to protect local species. The solar project also promotes vegetation.

Buckeye Wind Farm Project, Ohio, United States of America

The Buckeye Wind Project will be the first commercial utility-scale project in Ohio. Located in the Champaign County of central Ohio, the wind farm is being developed by EverPower Wind Holdings, a subsidiary of New York-based EverPower Renewables Corporation.

The first phase of the project will cost $380m. Upon completion, it will provide electricity to 42,000 homes. The project will offset greenhouse-gas emissions by 350,000t annually, while reducing the state's dependency on fossil fuels. Phase one of project received approval from the Ohio Power Siting Board (OPSB) on 24 March 2010.

The case later moved to the Ohio Supreme Court which upheld the approval provided by Ohio State for constructing the project. As of December 2012, phase one of project was in its final stages of obtaining permission.Construction was meant to begin in mid-2010 but has been delayed due to opposition from various affected authorities as well as a local citizens group. Two appeals were filed in September 2010; the first was filed by a local citizens group commonly known as Union Citizens United and the other one was filed by Champaign County, Goshen Township, Salem Township and Union Township. The appeals were heard by Ohio's highest court in the second half of 2011.

EverPower submitted an application with the Ohio state for the second phase of the project (Buckeye II) in May 2012. The proposed Buckeye II will provide electricity to 40,000 homes.

Construction of both the phases is expected to start in 2013. Nearly 600 jobs during construction and 38 permanent jobs are expected to be created by the project.

Buckeye II will be EverPower's third project in Ohio followed by Buckeye I in Champaign County and the Hardin Wind Project in Hardin County.

Financing EverPower's renewable project

EverPower has been awarded a $3m grant for the Buckeye I wind project under Ohio's Wind Production & Manufacturing Incentive Program. The programme was set up to support the development of wind power projects. Under this programme, the project will receive 1¢/KWh and an additional 0.2¢/KWh if the plant is installed with Ohio-made wind turbines. The incentive programme is a part of Ohio's alternative energy portfolio standard.

The project has also received financial backing from Terra Firm, a private equity arm of British company Guy Hands, which acquired EverPower Holdings for $350m in 2008.

Buckeye I wind project details

The Buckeye I wind farm will be spread across 10,000 acres of leased land and will be installed with 54 wind turbines. Each turbine, measuring 500ft in height, will generate 2.5MW of electricity, sufficient to power 600 to 750 homes. The type of turbines is not yet selected, but the project has been designed to suit either the Repower MM925 turbine or Nordex N100 or N90 turbine types.

The proposed project was initially designed with 70 turbines. The approval, however, was granted for just 54 turbines by the Ohio Power Siting Board (OPSB). The other 16 turbines were disapproved citing aviation hazards, as it was proposed that they should be constructed near Champaign's airport.The wind farm will have an installed capacity of 175MW and generate 135MW annually.

The Buckeye II wind farm, with up to 56 new turbines, will cover 13,500 acres of land next to Buckeye I wind farm. The height of the turbines will be 492ft from base to blade tip. The towers will be 328ft high. The installed capacity of the second phase will range between 91MW to 171MW.

If the second phase of Buckeye wind Farm is approved, the total number of turbines in the project will be 110.

RePower, GE, Vestas, Nordex and Gamesa are being considered as the possible turbine manufacturers for the second phase.

Ohio's wind farm grid network

The wind farm will be connected to the transmission system of PJM Interconnection, a regional transmission organisation, through the Dayton Power & Light network (DPL). It will be connected to Urbana, Mechanicsburg and Darby via a 138KV PJM transmission line. PJM Interconnection coordinates the transmission of electricity from the power plants to several states in the US.

Ohio's renewable energy generation potential

In 2008, Ohio's installed electricity capacity stood at 38,000MW, 86% of which was generated from coal-fired plants and 14% from nuclear and renewable sources. The state is one of the largest producers of electricity and also the fourth largest consumer of coal in the US.

As most of its electricity is generated from coal-fired plants, Ohio is also the highest greenhouse-gases emitting state in the nation. In order to reduce the greenhouse effect, the state implemented a new alternative energy portfolio standard in May 2008. The standard requires 25% of the electricity sold in the state to be generated from alternative energy sources by 2025, and at least half of it to be generated through wind power.

As on 11 February 2010, the state had the potential to install 55GW of onshore wind power that will generate 152TWh a year. As of May 2010, however, Ohio had used only 1.8% of its total wind power potential and ranked 27th in the US, with 7.2MW of wind energy production.