A green construction vehicle shines in the morning sun. The colossus on caterpillar tracks is an unmissable appearance at the workshop of machine builder Woltman in Giessenburg in South Holland. With its more than 100,000 kilos, this foundation rig belongs to the big boys. It can drill, vibrate and pile-driving to a depth of over thirty metres. With this type of machine, piles of half a meter thick are drilled into the ground, which hold bridges, windmills and high-voltage pylons in place.
It is therefore not the most energy-efficient machine. Due to the large power required to drive eight piles into the ground every day, a foundation rig of this caliber burns about 500 liters of diesel per day. This is different with the copy at the workshop in Giessenburg: this is the first of its kind without a fuel tank, but with a battery pack that can provide it with power for a full working day. This battery, which is located in a container next to the machine, has the capacity of twenty Teslas with 1.2 megawatt hours. After a night on the plug, the machine can be used again.
The machine is intended for BAM (turnover 2021: 3.7 billion. 21,500 employees). The construction company was the first to order an electric drilling and piling machine from Woltman and also helped with the development – the desired machine did not yet exist. It required a substantial investment of several millions, assures Richard Piekar, Purchasing Director at BAM Nederland. But one that is ultimately profitable. In the construction industry, which sometimes has a reputation for being conservative, it is a startling conclusion. Sustainability and achieving returns do not therefore have to be mutually exclusive.
Read also: Diesel out, battery in: construction wants electric (but can’t afford it)
Piekar comes to tell about it at the office at Woltman, where commercial director Ronald IJtema is already preparing coffee. “We have calculated everything, and it is a good one business case”, said Piekar. “You have to look at the total costs. The high purchase price makes it more expensive for projects, but you no longer have to buy diesel and less maintenance is required.”
For BAM, the decision to develop an entirely new machine came partly out of ambition and partly out of necessity. “If machines need to be replaced, we will do so with zero-emission equipment where possible. For example, there was recently an electrically powered one curl delivered, an excavator that can drive on rails. So we do this for the entire group, including the heavier equipment in the rail, infrastructure and foundation departments.”
‘Where possible’
‘Where possible’ is an important part of Piekar’s sentence. Although shovels, vans and loose equipment are already fully electric, this is not yet the case with the heavier construction machines. The equipment must be able to deliver heavy performance for eight hours in all weather conditions on the construction site. Battery technology hadn’t been that far for a long time and diesel was so cheap that it inhibited innovation. Moreover, the sales market is relatively small; few contractors can afford the new price of electrical construction equipment (more than twice that of a regular diesel) – let alone develop an entirely new machine. So from an economic point of view it is a rather risky operation.
Nevertheless, the construction sector will have to become more sustainable. The government goal, which construction companies endorsed, is to build emission-free by 2030. In addition, various rulings by the Council of State have made it increasingly difficult to work with diesel-powered construction vehicles in the vicinity of nitrogen-sensitive areas in recent years.
At machine builder Woltman (annual turnover approximately 15 million, 20 employees) they also notice the consequences of the sustainability task. Woltman machines regularly roll into the workshop, with the request to replace the old diesel engines with the most economical variant – and now also an electric motor.
The electric foundation rig probably would not have come about without BAM as the first customer. The builder helped with the development by providing usage data and thinking along with the design every other week. The certainty of payment also made it a profitable project for machine manufacturer Woltman. “Without launchcustomer you have to develop everything yourself. All requirements of BAM are incorporated in this machine. It achieves the same performance as a diesel one, and we were able to test everything about it.” For BAM the machine can go straight onto the construction site, at Woltman it gets a place in the catalogue.
According to the men at the board, the fact that this machine was developed in the Netherlands is partly due to the Dutch nitrogen problem. The situation not only offers concerns, but also opportunities for the industry, says Ronald IJntema of Woltman. “You see that other companies in our sector are also working on electrification. Knowledge is also shared about it. There is also interest in Dutch innovations from abroad, says IJtema. “In Germany and Scandinavia, what we develop here is viewed with great interest.”
The foundation machine was drawn on paper in ten months. “We found out that a normal machine consumes quite a lot of diesel while it is idling and actually doing nothing,” says IJtema. “The electric one then simply turns off, just like a Tesla at a traffic light.”
The team also encountered all kinds of practical design issues. A lot had to do with the battery pack, which comes on the back of the vehicle and weighs more than fifteen tons. IJtema: “Suddenly you get questions like: how are we going to keep that machine in balance during work? How do you distribute the forces when you are vibrating or drilling? And how do you get that battery to the construction site? It is in a container that has to be hoisted onto the foundation machine on site. It is too big to be assembled and transported.”
In Germany and Scandinavia, what we develop here is viewed with great interest
Ronald Intema commercial director Woltman
Then there is the most technical aspect: the electric motor and the control. Machine builder Woltman enlisted the help of VSE Industrial Automation from Schoonhoven, a technical company that develops control technology for bridges, among other things. Not necessary with a normal construction machine, but now that the control had to be driven entirely electronically, the knowledge of the automation company was indispensable. “The battery became a project within a project. That thing has to withstand anything. Against the ungainly vibrations during work, but also against temperatures of minus ten and rain. Normal batteries couldn’t do that,” says commercial director Radboud van Dusseldorp.
According to Van Dusseldorp, it will also take some getting used to on the construction site. If the machine malfunctions due to an inexplicable technical problem, you don’t grab a wrench but grab Woltman’s phone number. “And if it is really specialist, they call us.” The electric motor is protected in such a way that the voltage goes off when you open the valve. And that is not for nothing. “There is not 100, but 700 to 800 volts on that battery pack. If something were to go wrong, not only would your hair stand on end.”
Shareholders
Although the sustainability goal is noble, the price tag also counts for BAM in addition to performance. We also have to be accountable to our shareholders. Of course I cannot come up with just a nice story, there must also be a return”, says Piekar. Whatever he wants to say: if it were not financially feasible, the investment would not have been made. Due to the operational sensitivity, he does not want to discuss the calculations he made for the foundation rig in detail. In any case, this involves an investment of several million and what is clear is that the machine will pay for itself before the end of its fifteen-year lifespan. “As long as it can run fully and we get new orders with it, we can count on this. What is important, however, is that our clients recognize the added value of it and also include that in the tender.”
It is a frequently heard plea to the client, in many cases Rijkswaterstaat or ProRail. Giving builders with zero-emission or energy-efficient construction equipment an advantage in the award process makes it more attractive for companies to invest. And that is necessary, say the men at the table. The entire supply chain will have to make the switch from diesel to electric if construction is to be emission-free by 2030. Piekar: “It is simply becoming more expensive to purchase new machines. We cannot only sponsor that, it must also come from other parties and the clients.”
#Sustainable #profitable #construction #machine #shows