Green revolution

24 March 2022

Lifting is overwhelmingly powered by fossil-fuel diesel. How can it become sustainable? Julian Champkin finds encouraging progress towards a carbon-neutral industry.

Crane company Ainscough is to run its entire fleet on hydrogenated vegetable oil, known as HVO for short. HVO is a substitute for diesel fuel – but when it is properly sourced, as Ainscough has pledged, it is a sustainable and renewable fuel that is carbon neutral. It does not add to the CO2 in the atmosphere that is a main cause of climate change. And diesel engines can run on it perfectly satisfactorily, with no need for adjustments to the engine and without any loss of performance. Ainscough has more than 400 cranes and 30 or more heavy transport vehicles; they will all be run on HVO. This, Ainscough clims, makes it the first first crane company in the world to adopt HVO across its fleet.

The move will reduce the company’s CO2 emissions by 95%, or 14,000 tonnes of CO2 per year. Ainscough intends to go further. An additional 5% reduction has been achieved with other energy-saving initiatives, which include using the UK’s residual carbon offsetting scheme. Ainscough as a company will therefore be carbon neutral from April of this year – essentially, from the time that you read this article.

It is a considerable, and a praiseworthy, achievement. It is also a necessary one, if the balance of life on the planet is to remain as we know it. Others in the industry – crane manufacturers and crane and heavy lift operators - are moving the same way. Yet lifting is an industry where almost from the start of industrialisation fossil-fuel diesel has been the most practicable, and almost the universal, source of energy. Eliminating diesel from the crane operations is neither simple, nor always straightforward.

Electricity is the obvious alternative energy source, and manufacturers have been bringing out mains-powered and battery-powered cranes, as well as hybrids that use a combination of internal combustion and electric. Hydrogen fuel cells are another option – a constant stream of the gas is fed in to them, and electricity comes out. Non-electrical options include HVO, as we have seen, or hydrogen as an internal combustion fuel. The UK government has a ‘Hydrogen Policy’ document for replacing gas home heating with piped hydrogen by 2050; that might or might not result in hydrogen refuelling outlets for vehicles becoming available at normal petrol stations.

First, though, let us talk electric power. Both new and existing technologies are relevant; and if further progress is to be made supply chains, manufacturers, technology developers and end-users will all have to be involved.

United Kingdom Research and Innovation or UKRI, is a public body charged with encouraging and facilitating that process. Through it the government has invested nearly £80 million into upscaling the manufacturing of Power Electronics, Machines and Drives (PEMD) - essentially the technologies that will make electrification possible, especially for off-highway and construction vehicles. Professor Will Drury is its challenge director.

“Whether your electricity comes from a battery, a fuel cell, the mains or whatever, irrespective of its source you need to convert it into mechanical energy to do the work,” he says. “To do that you use some electronics and electric motor – a power train. And those are the components that will drive the sustainability revolution.

“Some of them can be the application of existing electronics, but we are looking for new and more modern, more efficient electronics now, using what are called wide bandgap devices that allow us to convert electricity much more efficiently. The UK is world-leading in some of that R&D; we are working on supply chains to allow those to be made and distributed here as well.

“There are also older motor-types that are being brought into the 21st century with increased efficiencies; technologies such as switched reluctance motors use no magnets, thus saving material resources and the energy and destructiveness of mining them.

“Technologies already used in other application can be transferred to cranes,” he says. “Elevators in office buildings are essentially lifting machines, and are almost all electrically powered. Already in this country we have some world leading elevator manufacturers that make the electronics for those: Seimens are based in Congleton, ABB are doing stuff in Warrington, Nidec Control Techniques are in Powys, and there some start-ups from the beginnings of the 2000s. So we have people making the product for a different application that, perhaps with some minor tweaking, will do what you need for cranes.

“So it then becomes application engineering. Somebody has a problem to solve: we at UKRI are not going to be the ones to sit there and engineer the solution but we can say ‘Hey, you might want to talk to A and B and C: these people are working in just the area you need.’ So we are definitely building that ecosystem of the electrified technologies that is absolutely critical to the future.”


More than just different cranes are needed: it is a whole different philosophy of construction. “It is all about trying to make the construction industry work more efficiently," Drury continues. "As you are no doubt aware the construction industry works very inefficiently at the moment. More than 50% of activity is not value-adding. You've got people waiting around for things, people who are operating machinery will be sitting there with it idling for significant proportion of the time waiting for other things to happen and blasting out noxious gases while it waits. And that is not environmentally friendly at all. At the moment construction sites work on a frankly ad hoc basis: materials and labour show up if you're lucky roughly when you expect them, and you do lots of work on site. Where we want to get to is a situation where the majority of value-added work is done off site.

“Wall assemblies, bathroom pods, cladding panels and so forth can be manufactured and put together in factories. Bring the prefabricated units to the site. You can then lift them and put them in place very efficiently and you end up with fewer deliveries, faster and much more efficient operation (which you have rehearsed already in virtual reality), much less in the way of cutting and shaping and fitting on site.

"And that that vision involves everybody's time and equipment being used highly efficiently, and taking a fraction of the time on site – and in huge saving in energy use and emissions.”

That vision will affect the types of crane that are wanted. Already prefabricated concrete cladding for high-rises are increasing the demand for larger-capacity cranes to lift and place them. The hope is that this will spread throughout the UK house-building sector, as it already has to a large extent in the US.

“It is happening, with considerable momentum, at the moment,” says Drury. “One of the reasons for that is the UK government’s procurement policy with regard to buildings. The government spends between 20 and 40 billion pounds a year on hospitals, roads and the like. In December 2020, as a result of the ‘Transforming Construction’ challenge, they rewrote the rules for procurement of buildings to say they will judge their suppliers on the basis of how much they are manufacturing in factories, on how thoroughly digitised their processes are, and how green their delivery systems are. All of this has given massive confidence to the market, and suppliers are now investing in these new techniques.

“And, of course, that is a virtuous circle, because if you invest in the right things you will significantly reduce the amount of energy you use, and that you have to pay for. You will significantly reduce the amount of labour you are using and that you will have to pay for; and incidentally, you will also significantly reduce the amount of materials that get wasted. At the moment the average construction site sends one hundred skips of rubbish, mainly to landfill, for every million pounds spent on site. That wastage should plummet.”

All of which helps the green revolution and reduces greenhouse gas emissions. And the technology to bring it about? “It will be varied. There is no ‘one size fits all’ for new cranes. Mobile cranes have two special factors. First, they operate in two modes: they drive to the site, then once they are there they start lifting things. There is no reason that the best electric solution for travel is also the best solution for the lifting mode.

“The second special factor for cranes is that they lift loads – which takes energy - and they also lower them, which gives energy back; and that regenerated energy can be fed back into a battery to be stored and re-used. So for a crane a battery is a good option for the ‘at work ’ mode; but whether it should be the sole source is an open question. Fuel-cells may be better for transport; but if someone said ‘We are going to make a crane and it’s only going to use fuel cells’ I would be very surprised.

“Getting an all-terrain crane rolling on a road takes a huge amount of power. Once it is going you've not got a problem but getting it going is always going to be the biggest challenge. People are looking at what is called solid state batteries, which allow higher energy density. If that happens it will be a step change. But until then I would expect to see hybrid cranes - hybrid as in two different types of electrical storage.

“There could even be more electrical techniques. So-called ‘supercapacitors’ store energy but release it very quickly. You might think of those for tasks that involves snatch lifting. So we are in quite an exciting space from an engineer’s perspective.”

That is all good theory; but how does a lifting company set about turning itself green in practice? Take an example from Mammoet. The company carries out the sort of very-heavy lifts where you think diesel must be the only choice, so how is it going green?

First, it had to want to, and it was ahead of the field in this. “There were lots of people in the company who were passionate about wanting to do something, wanting to make a difference,” says Erica Gray, who is global sustainability manager at Mammoet.

The company waned to integrate all its efforts, to come up with a unified strategy and plan and they appointed Gray to do just that. “When I started I was literally mapping what was going on; which was a lot, but it was all taking place in isolated pockets. So we did a sustainability assessment. It is quite common within business now and is something Mammoet felt we should be doing as a responsible business; it is very much in line with our values as a company.”

The approach turned out to be about more than just reducing their own emissions. “We were breaking new ground because sustainability wasn't something that had really been developed to any great extent in the industry. A second element was engagement, because this isn't something any one company can do on its own. So we really need to reach out to work in partnership with our customers and with our suppliers and communities: it really needs to be a joined-up effort.” The final element, she says, is being a responsible employer.

A key word, as with Professor Drury above, is ‘efficiency’: “There is still a huge amount of space for us to be operating more efficiently. Every saving in fuel equates to fewer emissions.

“We discovered that by far our biggest impact is the composition of our fleet. We have a massive fleet of equipment, and it's all running on diesel. So we want to focus on carbon emissions, and to do that we need data.

"We've been collecting data for a while now... which lets us look at the basics in terms of fuel consumption, and therefore emissions, for each machine. We set ourselves clear targets: we said we will go to a 30% reduction in carbon emissions by 2030 – based on a 2018 baseline.

“We are also aiming to have 30% of our hours of operation carbon neutral by 2030. So there's some quite ambitious goals there.

“There isn't a well trodden path for how to achieve this. Some of it is the cutting edge of technical research and development; some is just implementing obvious stuff like not running your engines unnecessarily. It is also again about working with other organisations. What I tend to say is that we have three main layers to the cake. The first layer is the options that are available now, that are already on the market. There are some hybrid crane equipment options available, and there is also HVO, which you can substitute for diesel.

"We used that in a project last March, and it is a good transitional option because you can use it straight away in diesel engines – you don't have to adapt them in any way.

“We did testing before we carried out the project using it and the performance of the power packs that we used was not in any way inhibited by using HVO. You get the same performance but the carbon footprint of the fuel is far far less. Of course you have to be sure that the source material is sustainable: if your HVO comes from crops grown on destroyed rainforest, or on land needed for food, you are gaining nothing. The fuel we used is generated entirely from used cooking oil and wastes and residuals from the normal refining process. You have to trace everything back to its origin, or else have a trustworthy body to certify it. Ours has been certified by approved organisations – there are several - and I actually had the benefit of speaking to one of the academics who was involved in certifying it.

“There are ways that you can be reasonably reassured about the source of your fuel without having to dive into the entire supply chain yourself. Most of the companies that are offering alternative fuels will also give you assurance.

“So that is equipment and fuel. The third layer is really breaking new ground to change how things operate, the entire methodology. For example the wind sector has quite an interest in moving to low-carbon operations because it's very much in line with their fundamental philosophy; and they are looking at how could you work in a different way. Can you design towers that need a different type of lifting equipment that could be electric-powered, and that also could require far less in the way of concreting and civil groundwork? You might end up with towers that need something other than a crane to erect.”

That sort of blue-sky thinking is transformational, from the ground and the design-stage up: “It's about changing the way the people work. It’s about rethinking how we do things. We can talk about new fuels like hydrogen to power some of the bigger cranes and it sounds very simple, but actually doing it is hard work. There are huge gains to be made still just by changing the way that people use the equipment, the way they drive.

“There's a lot still to be gained in terms of helping people realise we all have a role to play in this. The big big shift is in how interested people are in this topic within our sector and within the heavy industries generally. In our company there is pressure from shareholders, from customers, and from the board, and they are all pushing the same way. I talk to engineers who have been with Mammoet all their lives and are coming up to retirement and want to leave the industry in a better state than they found it; I see the younger generation coming in with new ideas. The company is full of engineers, and engineers love solving problems. Together they want to take all of their information and knowledge and experience and figure out how they can use it to make the industry fit for 21st century. But we really do need to start acting now.”

See our video with Erica Gray at: videos/

Ainscough’s crane fleet is zero-emission
This 900t topside was moved by Mammoet using HVO fuel, with significantly low carbon footprint