Fuel for debate

5 May 2022


The world’s energy supply faces crisis. Climate change, and the war in Ukraine, are forcing a re-think of future supply. New sources will need new lifting gear. Julian Champkin reports.

The Russian invasion of Ukraine has, among other things, concentrated minds on energy supply. Mainland Europe pre-invasion received around 40% of its gas from Russia, via the existing pipelines, and Nord Stream 2 (a 1,234km gas pipeline from Russia to Germany via the Baltic Sea), which was completed last year at a cost of $11bn and awaited only regulatory clearance, would have added as much again. With question marks over immediate Russian supply, and with Nord Stream 2 indefinitely on hold, Europe faces a possible major energy shortage this winter.

The EU has proposed a plan to make Europe independent from Russian fossil fuels before 2030. Renewables such as wind and solar will play their part. Germany has rejected nuclear power. Britain, though, has not; and in April this year Prime Minster Boris Johnson announced fast-track planning procedures for a possible seven new nuclear stations.

Whiting in the US is a major supplier of lifting equipment to the nuclear sector.

“Lifting and handling in nuclear installations requires a hugely different approach and skillset to regular commercial cranes and manipulators,” says Jeff Negreti, director, Nuclear Projects and Special Cranes at Whiting Corp.

“Off-the-shelf solutions are not sufficient; neither is the standard documentation that cranes are sold with. What keeps me awake at night is paperwork,” he says. “A normal crane might take 12 months from commission to delivery; for a nuclear application that can easily double. Every piece of material, and every process, requires certification, at every stage.”

The term ‘Nuclear crane’ covers a lot. “A facility will have many different cranes of many different types,” he says. “The reactor room crane will have the largest capacity, of around 150t; that’s because as well as feeding in the fuel rods it has to lift the reactor head, and that is a heavy component. It can be a polar crane, which runs on circular rails laid out at height above the reactor. It is a design almost unique to nuclear facilities thanks to the circular geometry of reactor rooms. The turbine hall crane is similar to fossil-fuel turbine cranes, except in PWR-type reactors where the turbine steam is radioactive so the crane has to be made accordingly. And you need cask cranes to take the spent fuel out of the reactor and transport it to vehicles to take it to store on-site.

“A lot of our business is supplying crane coverage for plants during refuel outages; every 18 months they perform a fuel change cycle, where they open up the containment vessel. At that point we perform extensive inspection of the crane, which by OSHA rules we have to do before they can even run it. We have at least two people staying on-site day and night just in case they have a problem on the crane, because an outage costs them over a million dollars a day and they don’t want to extend it for a crane issue.”

Decommissioning a nuclear plant is as crane-consuming as commissioning it. Fred Waugh is Whiting’s decommissioning specialist. “It takes 10 years to decommission a site from start to finish,” he says. “Much of the work is done using the facility’s own cranes, and we have to keep those in safe condition. Currently the US is decommissioning Yankee in Vermont, Three Mile Island in Pennsylvania, Indian Point in New York, Diablo Canyon in California; a lot of older plants from the 1970s will not be getting their licences renewed, so that will provide work for us.”

SCX of Sheffield is a UK specialist in nuclear lifting. Its first nuclear project was the decommissioning of Berkeley power station in 1997. Currently it is working on the decommissioning of Dounreay in northern Scotland. One major project there is a facility to store intermediate level waste, packaged into cement and steel drums, which are then placed in long-term storage.

SCX has designed and delivered a semi-automatic crane to handle the 500-litre drums. It moves them to their correct locations and sets them down in their correct positions in the store.

It is a Street ZX84 hoist, with 40m long-travel and 12.2m cross-travel, which gives it access to all areas of the drum store. Lift speed is 6.0 to 0.6 m/min and cross and long travel is at 15 to 1.5 m/min. Lift height is 10.4m. A four-wire rope fall and true vertical lift give the required pinpoint positioning, and the hoist has been de-rated for additional safety.

An integrally connected drum management system knows where any asset is at any time, with data fed to a desk in the control room. Safety and redundancy of course are paramount: the crane includes CCTV and remote recovery in case of primary mechanical or electrical failure.

It has a MotoSuiveur hoist safety system, with supplemental independent winches for mechanical recovery. Its design working life of 100 years is supported by calculations, documentation and comprehensive acceptance testing. The crane is sacrificial, to be left in the drum store once its job is complete.

At the same time as announcing his nuclear plans, Boris Johnson urged the creation of gigawatts of floating wind farms to secure future energy – and wind power has indeed been the big energy success story of recent years.

Wind generators sit on top of tall towers. Getting materials up to them needs hoists, and with the growth of wind farms specialised hoists have appeared to satisfy that need.

High speeds and long lifts are the requirement, as is the ability to work instantly on demand after months or years idle - frequent maintenance trips to the top of a 100-metre tower being something one would want to avoid.

So for example the gearbox and slipping clutch of the Demag DC-Wind chain hoist are designed to be maintenance-free for up to 10 years. It can lift loads of up to 1,500kg with hook paths up to 180 metres.

Dana Inc. of Ohio makes power- and energy-management systems for vehicles as its core business but has diversified into nacelle cranes. “The growing need to service equipment on wind farms has brought about the need for them,” says Jared Bryan, senior manager, Corporate Communications. “They have been deployed in multiple wind farms in Northern Europe, China, and the U.S. “Our hoisting winches are fitted within the nacelle of the turbine. The winch allows maintenance staff to lift and lower the turbine safely for repair or replacement activities. We also offer specially designed winches for lifting personnel or a maintenance platform.

“The design we provide is for offshore wind nacelles rather than on-shore,” he says. “They are hydraulic hoisting winches with integrated fixed-displacement axial piston motors. They come with an integrated torque sensor, an encoder, a top roller and counterweight, and a spooling device for 150-170m of steel rope. The personnel lifting application and the high rope capacity are particularly key in this application. So too is great starting responsiveness. And our nacelle cranes give a smooth ride even at low speeds, which again is important both for personnel-carrying and for cargo.”

The US installed 17GW of wind energy in 2020 [source: DIE report, 2021] to bring total capacity to 122GW. But the vast majority of that is from on-shore farms. It has up until now lagged well behind Europe and the Far East in offshore wind installation. Only two offshore wind projects currently operate off America’s shores, and both are small: a 30-megawatt wind farm near Block Island, Rhode Island and a 12-megawatt pilot project in coastal Virginia.

The Trump administration had little focus on renewables, and regulatory difficulties did not help off-shore construction. State waters extend to three miles offshore, beyond which federal rules apply; which meant that most windfarms had to obtain licences from both.

The Jones Act, of 1920, which specifies that only US-made ships may carry cargoes between US ports and applies also to the specialist vessels, which are needed to install windfarms, has limited the number of such vessels available.

The Biden administration, however, as part of its climate agenda announced in January this year a record-breaking offshore wind lease sale, covering nearly 500,000 acres (200,000ha) off the coast of New York and New Jersey. It is expected to generate as many as 80,000 new jobs in the wind-energy sector as well as up to 7 gigawatts of clean electricity.

Financial incentives will be available for wind-turbine materials that are made in the U.S., but foreign-made components are not barred; which is why Seasight Davits, of Ringkøbing in Denmark, was able to announce, at the end of March 2022, its first US orders. They are supply contracts for a total of 77 windfarm davit cranes for projects off the US East Coast. The cranes each have an outreach of 4 meters and a lifting capacity of 1 ton. “Signing these contracts was of particular importance to us as it led to our establishing our third overseas subsidiary, Seasight Davits US,” said Alex Kristensen, Seasight CCO. “In January 2022, Seasight Davits US became a reality with its registration in the State of Delaware.

The next step is to register in New York State, where the subsidiary will be located.

“The timing for winning these projects is very fortunate for us,” said Kristensen. “We saw how the US offshore wind industry was starting to develop rapidly, so it became part of our strategy to expand with a US subsidiary within a certain timeline to become part of the supply chain over there.”

As well as the supply contracts, Seasight Davits is hoping to receive a two-year service agreement. “Service agreements make things even more interesting because they, unlike a supply contract, gives prospects of long-term and continuous work, which is very important when entering a new market and even more so when establishing a new company. We will start manning up with personnel in the US from the beginning of 2023 as we need to have a local team of technicians ready when the annual service campaigns of the davit cranes commence, which is expected to be in 2024.”

The davit cranes will be produced at Seasight Davits’ facilities in Denmark. Deliveries are scheduled to start at the end of the year.

Hydro-electricity supplied around 16% of global power in 2019. Hydro is renewable and generally considered ‘clean’ – although studies suggest that the area of water in large man-made reservoirs emit methane in quantities that are by no means negligible – methane being around 30 times more powerful than CO2 as a greenhouse gas. The environmental impact of damming a large river can also be huge. Small-scale hydro schemes, however, avoid much of these criticisms.

Mona Lifting, of Anglesey in Wales, has supplied overhead cranes to nuclear stations and to CERN; but also the design and commission of a manual overhead travelling crane specifically for fitting in small hydro power stations. “This crane is usually fitted at the construction stage and can be used to install the turbine and other equipment without requiring any power input,” says operations director Gethin Jones. “The crane is modular and has versions from 1 ton to 30 tons.

“Mona Lifting has installed a large number of these cranes in the last few years.”

An example is Balnacarn powerhouse, at Glenmoriston, near Fort Augustus in the Scottish Highlands. This is a 700kW high-head hydro scheme. The powerhouse is beside a domestic property, so particular attention had to be paid to the visual impact and to noise. A relatively slow turbine and variable speed ventilation system were specified to reduce noise at source and the powerhouse was designed to be ‘rustic’ and as small and low as possible. This required the intelligent use of space within it to accommodate the large and relatively heavy turbine. Mona Lifting designed and manufactured a 7t x 3.8m span manual underslung overhead travelling crane to fit the parameters.

Waste-to-power is generally thought of as small-to-medium in scale; but Konecranes in Dubai is involved in what will become one of the world’s largest such schemes. The Warsan facility will treat 5,000 tons of non-recyclable municipal solid waste a day, which adds up to 1.9 million tons a year. It will be burned to produce 200MW of electricity. In addition, metals will be recovered and construction materials will be produced from the bottom ash.

Konecranes will provide four 28t x 30m span fully automated Waste-to-Energy process cranes for the project; they will be equipped with 18m3 grabs. Konecranes will also supply a 65t x 19 m span crane for boiler maintenance. The cranes include smart features such as sway control, shock load and slack rope prevention, protected areas provision and target positioning. Konecranes digital service Truconnect will monitor crane use and maintenance. And, since this is after all a recycling plant, the cranes themselves will also recycle the energy they produce: Konecranes’ DynaReg system regenerates the power that is produced by the hoists lowering their loads and feeds it back into the grid. The cranes will be delivered to the site this year, with handover in 2024.

That last ability, of hoists that are lowering loads being able to feed the regenerated electricity back into the grid, is central to another power application – one that may just turn out to be critical in the adoption of renewable energy. See the p26 box (‘Hoist Stores Power’), which explains how the humble hoist might possibly save the planet, or at least contribute significantly to salvaging what is left of its current climate. Optimists read on.

SCX has designed and delivered a semi-automatic crane to Dounreay.
SCX Magnox drum lifters in testing and operation mode.
SCX is currently working on decommissioning Dounreay, in Scotland.
Dana’s wind hoist is designed for offshore...
Demag’s DC-Wind hoist fits inside the nacelle
A manual lift hoist from Mona for a small hydro project
... Seasight’s hoist, destined for the US