Building new hydro in Canada8 December 2014
Canada has a range of large new and refurb hydro projects under construction. Report by Patrick Reynolds
Canada is adding to its tally of long-term hydropower investment in large projects with more construction and under development. The country also continues to see a focus on small hydro initiatives.
Among the big schemes, construction is starting in earnest on BC Hydro's John Hart redevelopment project, and the utility is well advanced in procurement for its 1.1GW Site C new build scheme. BC Hydro has a variety of other projects underway in its capital programme, including improvements for major assets on Peace River, and upgrade works at Ruskin dam and power station.
Another major new build project getting underway in Canada is Manitoba Hydro's 695MW Keeyask scheme, and in mid-year ground-breaking took place for the main works.
Ontario Power Generation (OPG) recently reached milestones on its Can2.6 billion Lower Mattagami scheme when the first units in the expansion project were brought online. OPG has reported that follow-on analysis of its completed Niagara Power Tunnel scheme have shown that efforts to complete the delayed project were not only faster but proved less expensive than had been expected.
Major works continue on Hydro-Quebec's hydro schemes, and with so much having been achieved over recent years it construction focus is now on the four projects of the 1570MW Romaine scheme.
Nalcor Energy is also driving ahead with construction of the first stage of the Lower Churchill scheme. Major concrete pours have commenced for the key structures.
BC Hydro has started with the main works for the Can$1.1 billion John Hart redevelopment project, and its plans include a range of other improvements and additions - as well as Site C, a new build scheme getting close to site work.
Mid-year, turnkey joint venture contractor InPower BC broke ground for the main works to redevelop the John Hart site, on Campbell River. Before the end of 2014, underground works are due to be well underway on the design and build project which is due to be completed in 2018.
The project will see the 126MW plant (only operating at 121MW) upgraded to a 132.2MW power station, and generate an average of 835GWh of electricity per year - an increase of 7%.
The site has been in operation on Vancouver Island since the late 1940s, and will see the contractor replace a number of the key structures - the powerhouse and penstocks (3 x 1.8km), which will be removed in favour of a new 2.1km long headrace tunnel. Other changes to the infrastructure include construction of a replacement intake and bypass facility.
InPower BC is a special purpose company (SPV) wholly controlled by SNC-Lavalin. Working for the SPV, the companies performing the different tasks are: SNC-Lavalin and Aecon, working in joint venture on the design-build and civil works; subcontracted to the JV is Frontier-Kemper/ASL Partnership to undertake the tunnelling and underground works; Impsa is designing, manufacturing and supplying the turbines and generators; SNC-Constructors (Pacific), Inc, will handle balance of plant; and, specialist environmental services are provided by Hatfield Consultants.
SNC-Lavalin, supported by Impsa, beat the other two shortlisted parties for the contract - Elk Falls Energy Partners, and Salmon River Hydro Partners. It was chosen as preferred contractor in November 2013, and following final discussions a contract was signed with BC Hydro in February 2014.
Further details on the project are included on pxx.
Site C will be a major addition to BC Hydro's asset base, and is designed to generate an average of 5100GWh of electricity per year from 2023. After securing the Joint Review Panel's verdict of Site C being a cost-effective way to significantly boost the region's energy supplies, the utility issued a Request for Qualifications (RfQ) for the civil engineering works package.
The project is located on the Peace River in the northeast of the province. Key structures on the project include two concrete-lined diversion tunnels (2 x 10.8m i.d.), and two dams - an earthfill dam (1050m long, and 60m above the river level) and a RCC dam (800m long and 70m high). The civil works package will also include concrete construction for the powerhouse and the spillway.
Subject to approvals including environmental, the procurement schedule is for construction to start around the third quarter of 2015.
Also on Peace River, two existing major assets - the WAC Bennett dam, and beside it the 2730MW Gordon M Shrum power plant are key parts of what BC Hydro calls the 'cornerstone of our electrical system.' The powerhouse generates almost a quarter of the utility's output.
Built in the 1960s, the dam is having some improvements, and the powerhouse is being upgraded by a programme of 19 projects.
Works being undertaken, or planned, at Bennett dam include: upgrades to open casings left in the core after sink hole repair works in the late 1990s, and possibly installing new monitoring instruments; grouting for observation wells; spillway gate and chute upgrade; and, rip-rap replacement.
A key stage of the powerhouse improvement is replacing five units, which will increase output by 177GWh of output per year. In 2010, BC Hydro received approval to undertake the upgrade.
Three turbines have already been refurbished and upgraded in a Can$198.6 million package - and a cavitation mitigation programme has been implemented for all units, following discovery of the problem after the first refurbished unit was checked after some operational time, says the utility. The final two units are to be refurbished and back in service by 2017.
The refurbishment programme also includes rotor pole rehabilitation, and upgrade of the control systems for all units in the powerhouse - 10 in total. Some of the five not being upgraded are having new exciter transformer. Out in the switchyard, refurbishment programme for transformers is also underway.
Other upgrade works on the Peace River include replacing a transformer at 700MW Peace Canyon powerhouse, and was recently finished. The dam at the site was completed in 1980, and preliminary design is nearing completion to upgrade the six-gated spillway.
A package of improvement is needed for Ruskin dam and the 105MW powerhouse, which was built in 1930. It includes: a new cut-off wall to control seepage at the west (right) bank of the dam; spillway upgrades with seismic resistance; and, refurbishment of the generation units and also a seismic upgrade to the powerhouse building. The switchyard is to be moved.
Golder Associates worked on the new cut-off wall, and Voith is supplying the new generation units, and Flatiron-Dragados JV is performing the civils works for the dam and powerhouse. Under a partnership agreement, five new spillway gates will be supplied by HMI Construction, Inc. The improvements are to be completed by 2017.
Another large project, the Keeyask scheme has been anticipated for a number of years and is important for exports to the US electricity market. The project is being built on the Nelson River. Once completed in 2020, the plant's average annual energy output is expected to be 4400GWh, with dependable output of 2900GWh.
Main civil works recently commenced on site, and are being performed by BBE Hydro Constructors LP - a limited partnership joint venture of Bechtel Canada, Barnard Construction of Canada, and EllisDon Civil.
Voith is supplying seven vertical, fixed blade propeller turbines, and the generators, to the plant which will operate under an average head of 18.3m. Model tests have been completed, and early design work started mid-year. The units are to be commissioned over 2019-20.
Manitoba Hydro is developing the project in collaboration with four of the First Nations. They signed the development agreement in 2009, and when the utility then signed a series of power supply contracts totalling 495MW it triggered the development of the Keeyask project, plans for which accelerated from 2011.
The other key construction projects underway for Manitoba Hydro are the rehabilitation of Pointe du Bois spillway, and constructing the Can$4.6 billion Bipole III HVDC transmission line. Planning is in progress for a larger new build - the 1485MW Conawapa project, which could be constructed in the early 2020s on the Lower Nelson River.
OPG: Lower Mattagami
Following OPG's completion of the Niagara Power Tunnel, its key construction activity is Lower Mattagami expansion scheme which comprises four projects - Little Long, Harmon, Kipling and Smoky Falls. The scheme, part of OPG's northeast power group, is a co-venture with a First Nation, and is due to be completed in mid-2015.
The capital investment will add a total of 438MW and expand the Lower Mattagami scheme's capacity from 486MW to 924MW. Construction has been underway since 2010. Earlier this year, the first units were commissioned at two sites - Little Long and Harmon - adding 145MW to take the partially-expanded capacity of Lower Mattagami to 631MW.
The Little Long project involved adding a 67MW unit to the 138MW plant, taking the total capacity to 205MW. Works went well to schedule, and the unit was commissioned at the beginning of the year, joining the powerhouse's two existing units installed in 1963.
Harmon has been expanded by 78MW from 142MW to 220MW. The works also went well to schedule, and the new unit was brought online in June - ahead of the target date of September, OPG said in its second quarter results. The plant's original two units were commissioned in 1965.
The Kipling project is being expanded by 78MW from 154MW to 232MW. Early stage works in 2012 had some difficult rock conditions when constructing a cofferdam, but then pushed ahead. However, some further delay was caused in early 2013 by a breach to the cofferdam.
At Smoky Falls, the existing 52MW plant is being replaced by a new facility. The net addition is 215MW to take the total of the future complex to 267MW. OPG anticipates the unit to be commissioned ahead of the November target date.
With so much developed over the last few decades, and its completion of the Sarcelle portion of the Eastmain 1-A/Sarcelle/Rupert scheme in 2013, Hydro-Quebec now has its power plant construction focus on development in the Romaine catchment
For the Romaine scheme, Hydro-Quebec is building four projects in a phased programme over 2009-20. It expects a total of almost 8000GWh per year to be generated from the plants (each housing two Francis units).
One of the four projects is almost finished - Romaine-2, which has a capacity of 640M and is expected to be 3300GWh per year.
The main construction effort is on the second project in the programme - Romaine-1, which is lowest in the cascade and nearest to the Gulf of St Lawrence. Access and preparatory works for the 270MW project began in late 2012. Major civil works are nearing completion, and the plant is due to come online in early 2016.
Hydro-Quebec has preparatory works underway on site for the third project in the programme - Romaine-3, which is about 68km upstream of operational Romaine-2. The access and preparatory works for the 395MW project began at the same time as those for Romaine-1. Construction is due to be finished in late 2017.
The final project in the scheme - 245MW Romaine-4 - is not due to start construction until late 2016, after Romaine-1 has been completed. Therefore, the utility's construction effort will have moved up the river basin over 2017-20 and be focused on the two upstream projects to complete the cascade.
The 824MW Muskrat Falls project in Newfoundland and Labrador is the main construction focus of Nalcor Energy. The utility is more than a third of the way into the programme, which began early 2013. Detailed engineering and design work was recently completed, main construction is gearing up and the project is scheduled for completion in late 2017.
Muskrat Falls was cleared for construction by the Government of Newfoundland and Labrador in late 2012. It is the first, and smaller, of the two projects on the Lower Churchill scheme, the second being the 2250MW Gull Island complex. Lower Churchill also includes three large transmission link projects.
The project will have two dams - the north dam (32m high by 432m long), and the south dam (20m high by 325m long). Main contractor for the civils works is Astaldi Canada, which was selected in late 2013. In August this year, the first concrete pour for the spillway took place.
Shortly before then, in a mid-year progress update, Nalcor said its budget for Muskrat Falls and the transmission links had increased by approximately Can$800 million, or 13%, from the Can$6.2 billion estimate when the project was approved less than two years ago.
Nalcor says almost four percentage points of the increase is due to price inflation in the hot construction market. However, the majority - almost nine percentage points - is due to two aspects: design changes aimed at improving system quality and reliability (3.3%); and, operational efficiencies and construction productivity (5.6%).
The utility adds that the latest budget estimate includes contingency of Can$224 million, but excludes interest and financing costs.
Nalcor weighs the cost increase against revenues of more than Can$30 billion expected over the useful life of the project. It adds that federal loan guarantees obtained in late 2013 will save more than Can$1 billion in interest payments over 40 years.
Andritz Hydro Canada is supplying the turbines and generators, and hydro-mechanical equipment, for the project. Nalcor says work on units is progressing ahead of schedule.