The charge of change: electric construction in Barcelona

“There is a certain feeling in the air,” says Cristian Benito Manrique, “people are excited that this is real, that we are actually succeeding.” According to Benito Manrique, part of Barcelona’s Mobility and Infrastructures Management Team, when Barcelona decided to run its first construction site entirely with electric machinery, people felt like they had to see it with their own eyes. “They came to see it in person,” he recalls, “and you could witness them right there having the realisation in real-time that this can actually happen.”

Barcelona already has infrastructure for electric cars and electric motor bikes, and now the city is gearing up to make the shift to electric construction machinery as part of it’s city-wide push towards decarbonisation. “I’m optimistic,” says Benito Manrique, despite being frank about the challenges: “We don’t have experience, we don’t have the machinery here that we need… And that’s expensive,” he confesses. However, inspiration from other cities like Oslo, has given Barcelona the impetus to drive forward – a move buoyed by initial positive results.

Through participation in the European Commission’s Big Buyers’ initiative, which is supported by Eurocities, Barcelona was able to get insights from other cities into how it could transform its construction sector and slash local emissions. Now a new phase of Big Buyers is looking for input through this survey about which topics in the field of sustainable procurement cities want to focus on next.

A lucky start

The city’s first pilot test began with a serendipitous offer: A large supplier of machinery reached out and offered to loan them the hardware for free. “We gladly accepted,” Benito Manrique recalls.

I have a feeling that there’s a race
— Cristian Benito Manrique

And they’re not the only ones. Now suppliers are lining up to offer the use of free electric machines to the city. Why this enthusiasm? Benito Manrique suspects it’s not only out of the goodness of their hearts. Rather, it’s competition among the suppliers to get their foot in the door early. “They want to become the go-to suppliers for electric machinery. They know that this free contribution is an investment in positioning themselves as an important player in this field,” he says, “I have a feeling that there’s a race, and they are all fighting to be the first companies in this too.”

On-street charging for electric machinery

To push this sentiment further, Barcelona joined Oslo and other cities from the Big Buyers’ initiative to issue a joint statement of demand, announcing, among other things, that they intend to require fossil-free construction machinery in all the local administration’s public projects from 2025.

In the limelight

If it doesn’t work, we will see it on the news
— Cristian Benito Manrique

Armed with the right machinery, the city moved forward, deciding on works planned by the main water supplier in Barcelona for the pilot test. The project would involve works on 132 metres of pipe in central Barcelona, near La Pedrera, a major tourist attraction. The public nature of the project added a degree of risk; if the test failed, it would be highly visible. “I said great,” Benito Manrique jokes, “this way, we will know if it works or not, because if it doesn’t work, we will see it on the news for sure.”

The location of the pilot project, right beside the headquarters of a major Catalan land promoter, also allowed these major players in construction to witness the endeavour first hand.

Barcelona’s sustainability department was engaged to measure the emissions and noise during a construction project. The first half would be conducted with regular, fossil-fuel powered machines, the second half with electric ones. “In the same place, the same street, the same conditions, everything, so that the results would be comparable,” Benito Manrique explains.

First foray

The trial, which took place last summer, was not without hiccups. The first issue was finding an available electricity supply. The city decided to use a nearby charging point for electric motorbikes to supply the site. However, due to the degree of power required, they needed to rapidly source some accumulators to mediate the supply.

“We had to get two accumulators, so if one didn’t work, we could use the other one,” Benito Manrique says. To measure the results, his team took note of the energy consumption at the point of origin and also from each of the machines.

In the end, the risk paid off. The energy consumption was eight times lower in the electric phase of the test. Carbon emissions were seven times lower, taking into account the fact that some fossil fuels were used to generate the electricity in the power plant that was supplying the site.

Sound check

Anyone who has passed a building site will be familiar with the enormous quantities of noise that they produce. The city had hoped that electric machinery could significantly reduce the acoustic impact of construction on the acoustic landscape. While the noise reduction was less than expected, it was still significant. The sound of concrete splitting is just as abrasive whether it’s whether it’s created by electric or diesel machines.

“On average,” Benito Manrique reveals, “it was two or three decibels lower in the electric phase, compared to about 90 decibels with fossil fuels.” That might not seem like much until you take into account the fact that decibels are a logarithmic scale, meaning that just three fewer decibels indicates a 50% reduction in noise.”

However, not all improvements translated into financial savings. The war in Ukraine had driven up energy prices significantly at the time of the pilot, increasing the cost of running the electric machinery. Despite this, the overall increase for using electric machinery was a modest €500. Even without electricity prices coming down, Benito Manrique is hopeful that economies of scale will obliterate this difference.

Here in Barcelona in summer it’s really hot
— Cristian Benito Manrique

The labourers on the site didn’t experience any difficulty adapting to the use of electric machinery, a major plus for the potential of a rapid shift. A factor which was not measured was the difference in onsite temperatures with fossil fuel machinery. “Here in Barcelona in summer it’s really hot,” Benito Manrique emphasises. He speculates that machinery that puts out less heat may mean that electric solutions may have the added benefit of easing labour conditions for the construction workers.

The final hurdle

The second pilot test, unfortunately, faced a setback. A technical issue with the electric point of charge, meant that the results, though they gave a positive indication, were unreliable. Not wanting to wave around results that were not 100% guaranteed, the city decided to disregard this pilot altogether. Soon, the third pilot will be underway, and with a marked improvement in one significant regard.

Electric construction pilot area in Barcelona

“We have one last issue to face, which is the charging point,” Benito Manrique explains. By using electric motorbike charging points, the city was forced into a trade-off: more energy efficient construction, but a reduced offer for energy efficient mobility. “When we were doing the building work, no motorbikes could charge at that location. We don’t want to penalise the electric motorbike or electric car users!” Benito Manrique exclaims.

We don’t want to penalise the electric motorbike or electric car users
— Cristian Benito Manrique

His team have a promising but challenging solution in mind – using the city’s public lighting cabinets to charge the machinery. However, they are proceeding with caution. “Lighting is one of the central services that the city provides – we absolutely cannot leave a street without lighting because that could create a dangerous situation,” Benito Manrique says.

They have decided to go for it because, if successful, the upside is enormous: Barcelona has approximately 1,500 electric cabinets for public lighting, so electric construction would then be possible anywhere in the city.

Strong signals

Barcelona’s team is hoping that it’s clear messaging will send strong signals to suppliers that the shift towards an electric, emission-free approach is on its way. Though now still in its initial phase, the city envisions a time in the not-too-distant future when only electric construction machinery will be allowed within its territory.

At the moment, work is ongoing to design tenders that positively weight suppliers’ use of zero-emissions machines, rather than just looking for the lowest bid. “This is quite complex,” Benito Manrique admits, “but we intend to manage it this year.” The idea is not just for the city to operate in a cleaner way, but to use its purchasing power to promote positive change across the industry by demanding cleaner services.

People from all over have been calling up to find out more
— Cristian Benito Manrique

This mindset is the key pillar of the Big Buyers initiative: by using tendering and procurement of large public budgets, cities can inspire change across Europe and the world, forcing the market to adapt to a cleaner future. Barcelona and other cities involved have shared their key insights from experiences with zero-emissions construction in this lessons learned document.

Just as Barcelona was inspired by the progress that Oslo had made with electric machinery, news of its own successful pilot has sparked interest far and wide. “People from all over have been calling up to find out more,” says Benito Manrique, who has been invited to share his insights everywhere, from Madrid to Bratislava. All this excitement, he says, is what has created that new feeling in the air – an atmosphere that’s electric.

Anthony Colclough Eurocities Writer