The traction power mix is to become greener

Let’s start by looking at one of the biggest power guzzlers in the largest economy in Europe, namely in Germany. National railway company Deutsche Bahn (DB) consumes around ten terawatt hours of electricity every year – which is around as much power as is needed by the entire City of Hamburg. In light of its considerable power usage, DB has been looking into climate protection for quite some time now. In 2006, it first launched a programme aimed at precisely this issue, and since 2018 it has been assuring travellers “all passengers travelling on DB long-haul trains do so using 100 percent green electricity.”

Renewables account for just over half of the power consumed by DB

But this only applies to long-haul trains. Trains used for freight transport and regional travel still rely on conventionally generated electricity, as can be noted by simply glancing at DB’s 2018 publication on the mix of its traction power. According to the report, renewables accounted for 57 percent of the electricity needed for its train travel, whilst the remaining 43 percent came from conventional power plants. Hard coal covered 18 percent of consumption, nuclear power was responsible for nine percent and lignite contributed seven percent.

Hydropower plants based on rivers such as the Rhine, the Moselle and the Danube are currently responsible for supplying the majority of the necessary green electricity. By 2030, the portion of renewable energy in DB’s electricity mix is to rise to 80 percent. By the end of 2038, the company is ultimately looking to use 100% renewable energy to ferry its passengers to and fro, with photovoltaics and wind playing a larger role in covering demand. According to DB’s own statements, a timelier transition will not be possible due to the prior conclusion of long-term contracts with conventional energy providers.

Nevertheless, DB is now making greater efforts to secure new contracts for purchasing green electricity. Following a Europewide tendering process, DB concluded its first long-term power supply contract (PPA – Power Purchase Agreement) with innogy SE and RWE Supply & Trading. The power will be generated in the Nordsee Ost offshore wind farm, before being purchased by DB at a set price and used immediately. The supply volume amounts to 25 megawatt (MW), which corresponds to around eight percent of the total capacity of the wind farm, comprising 48 turbines with an aggregate capacity of 295 MW.

Switzerland and the Netherlands show how it’s done

Neighbouring Switzerland is planning to use 100% renewable traction power from 2025 onwards. Currently, around 90 percent of the necessary electricity is generated using hydropower. The Swiss Federal Railway (SBB) owns seven hydropower plants, which first and foremost generate power for railway transport. The remaining electricity is supplied by nuclear power stations.

The Dutch national railway company is notably further along than DB. Since early 2017, 100% of its traction power has come from onshore and offshore wind farms, with the result that all of its trains are carbon neutral. In 2014, the Nederlandse Spoorwegen (NS) concluded a long-term power supply contract (PPA – Power Purchase Agreement) with energy provider Eneco, and wind farms were built for the purpose. Half of the necessary power is sourced domestically, and the other half comes from wind farms in Sweden, Finland and Belgium.

Perhaps not quite as ambitious as Switzerland, but nevertheless, the French railway company Société nationale des chemins de fer (SNCF) is planning on becoming carbon neutral before DB. By 2025, state-run railway company SNCF is looking to cover 40 to 50 percent of its traction power mix with renewables, and by 2035 this figure is to rise to 100 percent.

Electrification of the track

As shown, a growing proportion of traction power is to be accounted for by renewables. But one problem remains: Many trains in Europe aren’t even electrified yet. They are, in fact, diesel-powered given that they travel along routes without overhead lines. In France and Germany, for example, around 40 percent of the rail network is not electrified, in other words it is lacking aerial lines.

And this isn’t set to change any time soon. In Germany, for instance, only 70 kilometres of tracks are newly electrified every year. Overhead lines cost at least EUR 1 million per kilometre, and planning processes take years. Not to mention the fact that the expensive investment is barely worth it on routes which are little travelled.

In this respect, too, more densely populated countries in Europe have progressed further. The Netherlands has equipped 76 percent of its tracks with aerial lines. And in Switzerland, three quarters of the railway network was already electrified back in 1939, with today’s quota amounting to 100 percent.

Alternative drive systems necessary

As electrification is extremely expensive, railway companies in Germany and France are looking for other ways to become more environmentally friendly. Thus, they are increasingly considering new drive systems such as hydrogen or battery-powered trains, which are to replace the regional routes which still rely on diesel locomotives.

In addition to the existing drive systems, there are also a large number of research projects underway pertaining to new ones. France, for example, is looking into drive systems which use rapeseed oil, whilst Germany is researching ‘blue-diesel’. Thirty-three percent of this fuel consists of converted biological residue and waste matter, such as used cooking oil.

Energy is also needed away from the tracks

Electricity for rail transport itself – despite best efforts – only accounts for about one-third of the total electricity consumption of railway companies, with the rest being consumed by stations, offices and other properties. In addition, DB’s logistics division Schenker also relies on diesel locomotives, trucks, aircraft and ships. But in this respect, there is still one final goal: By 2030, the group wants to reduce its carbon emissions worldwide by 50 percent and become a completely carbon-neutral company by 2050.

3 questions, 3 answers: Deutsche Bahn’s plans for the future

Roman Rühle, DB Environmental Spokesman, gives a short interview outlining the railway company’s plans to become more climate friendly.