Hydrogen is a promising fuel that can be used with fuel cells or in combustion engines. It is considered a better choice than batteries for heavy trucks and machinery as more energy can be stored on board. Commercial hydrogen equipment is generally limited to small power generators. Trucks and mobile machinery are generally available only as special test cases.
4.3 Uncertainty about performance and development
New technology brings change to established processes in the construction industry. New knowledge and experience have to be built up in all phases of construction. Added to this, there is uncertainty around what the new technology will be and how it will perform.
The construction industry normally does not have much room for experimentation. The same applies to investment in expensive equipment. The financial risk is typically the first barrier that contracting companies see when investing in emission-free equipment. Applying unfamiliar technology on a construction site can also cause unforeseen problems, resulting in additional costs and delays.
They also consider the likelihood of unforeseen problems with the technology if there is a slight chance that it will cause added problems.
Interviews with contractors highlight uncertainties that hinder the adoption of new emission-free technologies. They feel that the performance of the new equipment is not well-proven. Even if power and range are equal to conventional equipment, maintenance costs and practical lifespan are uncertain until more experience is gained. One of these uncertainties is battery capacity; some manufacturers recommend that only about 80% to 90% of battery capacity is used in order to increase lifespan. Stakeholders are often uncertain about the effective usable range of new emission-free equipment, as well as cold weather performance.
There are also concerns about obsolescence, with new technologies rapidly replacing the first generation of emission-free machinery. Distributors and other equipment specialists point out that batteries are not the final emission-free solution. An example of the fast pace of development is a pilot production run of 200 heavy trucks running on hydrogen. The majority of the trucks will be delivered to customers in Norway and Iceland in 2025.
4.4 Charging bottlenecks
Issues regarding the charging of battery electric vehicles and machinery on construction sites are a recurring theme in surveys and interviews.
Charging large battery electric machines and vehicles requires powerful grid connections and contractors often cite this as a limiting factor. Getting a connection to a new construction site can be problematic due to utility providers’ traditional processes. Construction in new areas can be delayed due to the development of grid infrastructure, while in older urban areas the electric grid may already be at full capacity.
High capacity chargers are used for battery electric machinery and the power drawn from the utility grid may be more than the building under construction will ultimately require. It is important to plan grid connections and charging schedules carefully, which is difficult when combined with the introduction of new technology.
4.5 Hydrogen infrastructure
As mentioned above, hydrogen is a promising fuel for heavy construction equipment and the technology is already available. Heavy vehicles and equipment using hydrogen are available today. These are, however, not as numerous as their battery electric counterparts.
Simple access to existing grid infrastructure has helped battery electric vehicles to gain popularity and lowered production costs. Although hydrogen is produced in most of the Nordic countries, there is very limited distribution infrastructure for customers in transport and construction. Perhaps the most important barrier to the deployment of hydrogen trucks is the lack of infrastructure.
The production of hydrogen is typically centralised in large units, employing electrolysis or methane reforming. Hydrogen is usually transported using trucks, either pressurised or liquified. Vehicles receive the fuel at hydrogen refuelling stations (HRS).