Whereas in many sectors the energy transition is being expedited and encouraged with financial incentives, Germany’s construction sites are evidently not top of the list for the country’s politicians. Yet, it is a field with huge potential for reducing consumption of fossil fuels and switching to clean energy sources on a significant scale.
A TREMOD study conducted on behalf of the German Environment Agency and published in March 2020 found that construction machinery in Germany consumes 72,440 terajoules of energy per year. That is roughly equal to 20 billion kilowatt hours of energy, the amount of electricity consumed by 10 cities of one million inhabitants each.
Since the nature of the sector’s work dictates that mobile plant and machinery has to be deployed on construction sites, it is hardly surprising that diesel/fuel oil makes up the lion’s share of the German construction industry’s energy consumption accounting for more than 50%. That is because, if no electricity supply is available in the site area, the necessary power is generally provided by diesel generators.
But even in the days before the current shortage of fossil fuels began to take hold, there was already significant potential for savings in the construction sector, potential which, unfortunately, is still far from being taken full advantage of. What is more, it is not only the contracting sector that has a strong interest in utilising this potential for energy efficiency.
In view of drastically increasing energy prices across the globe and the desire to minimise climate-damaging CO2 emissions as soon as possible, it goes without saying that all the construction industry’s stakeholders are called on to develop effective measures too. In the meantime, the project principals and machinery manufacturers are extremely interested in
the energy efficiency of their projects and products as well. Because in the face of climate change, responsible use of our resources is everybody’s business.
Furthermore, Germany’s act governing energy efficiency measures (EDL-G) requires all companies (apart from small firms) to be able to provide information about their energy usage.
Optimising energy efficiency
Swietelsky-Faber GmbH Kanalsanierung, like many other construction companies, operates a lot of mobile machinery that has mainly been powered by diesel.
For many years now, Swietelsky Faber has been actively optimising its energy efficiency and determines its energy usage in compliance with EN-16247-1 as part of its energy audit.
The potential identified for efficiency-enhancing measures is huge. In 2020, for instance, Swietelsky Faber consumed almost 7 million kWh of energy in the form of diesel, which still accounted for the lion’s share (96%) of the company’s energy consumption in 2016. Thanks to various measures to optimise its machinery, its repeat audit in 2020 showed that it had optimised its fuel consumption in relation to turnover by 8%.
Unfortunately, various steps need to be taken before the development of hydrogen fuelled cells reaches the marketable stage. In general, depending on the use case, the hydrogen either has to be highly compressed or cooled/liquefied using methods that are still relatively complex. Therefore, solutions for viable mobile hydrogen tanks and general transportability will first have to be developed before the construction sector can use hydrogen on a broader scale. Nevertheless, similarly to the rapid development seen in the e-mobility sector, it seems safe to assume that viable solutions will be developed in the foreseeable future, leading to the launch of hydrogen-fuelled construction machinery in the longer term.
For the time being, this means that the increasing electrification of machinery and equipment is currently the only path towards a climate-neutral construction site.
The consumption of fossil energy sources can be reduced by purchasing systems that are powered entirely by electricity. In the case of mobile construction sites in the infrastructure preservation sector, however, that electricity is generally supplied by diesel generators. But, by using various types of energy storage device (rechargeable batteries), the use of diesel generators can be avoided or at least drastically reduced.
In addition, the greater efficiency of rechargeable batteries as compared to diesel generators can result in an energy saving of approximately 40%. On top of that, using charging current from PV systems can reduce the amount of primary energy consumed by a further (approximately 40%). That is not all, in view of current price developments in the fossil fuel sector, an investment in energy efficiency will reach break-even point considerably earlier than was the case just a few years ago.
In addition, these measures result in a drastic reduction in the levels of noise and air pollutants at the construction site. That is a very welcome side effect, not just for our principals but for local residents and sitebased employees as well.
It is time to update funding programmes!
Bright prospects, then. However, the purchase of rechargeable batteries and the conversion of plant and machinery call for enormous investments by the construction companies. That is why, several years ago, Swietelsky–Faber applied to Germany’s Federal Office for Economic
Affairs and Export Control for funding. However, to this day the application has been rejected on the grounds that the machinery is not eligible for subsidies due to its mobile deployment on construction sites.
This exposes a fundamental problem. The transformation of the construction equipment sector towards greater energy efficiency and lower emissions calls for huge investments by both the construction companies that use the equipment and the manufacturers who develop the powertrains and machinery. The bottom line is that the purchase of energy-efficient plant and machinery generally calls for considerably higher investments than conventional equipment.
In order to create genuine incentives for the development, purchase and operation of energy-efficient plant and machinery for the construction sector, the general exclusion of plant and machinery that is not used exclusively on company premises needs to be dropped from the Federal Funding Programme for Energy and Resource Efficiency in
Business. Alternatively, it would be feasible to initiate a special incentive programme for mobile plant and machinery in the construction sector, which should however involve genuine subsidies and not merely
financing options.
Subsidies are a necessary incentive in order to offset the additional costs as compared to conventional equipment and thus encourage acceptance of energy-efficient plant and machinery. Germany’s construction industry association has been aware of this issue for
some time now and has already presented its case to the German Government multiple times. The energy transition is already underway on construction sites. It will be interesting to see whether any support is forthcoming from the political side.
In the construction sector in general and the field of trenchless sewer rehabilitation in particular, these principals can also send a clear signal when it comes to environmental protection by demanding an energy audit. Because in view of growing public pressure to meet climate protection goals, it would make a lot of sense if, during the planning
phase for trenchless rehabilitation projects, if principals were to demand that bidders have an operating and audited energy efficiency system in place as a criterion for being awarded the contract.
While it would not cost the principals anything, it would nevertheless be a huge benefit in terms of the project’s ecological footprint and economic efficiency.
