Smart Agri­cul­ture Can Protect the Climate  

Climate-neutral, emis­sion-free agri­cul­ture? It’s a compelling vision, but, as the saying goes, ’you can’t make an omelette without breaking eggs. “Agri­cul­tural produc­tion is based on biolog­ical processes in animals and in the soil, which can never be free of green­house gas emis­sions”, says Helmut Döhler, agron­o­mist and author, who spent decades at KTBL and has been working as a consul­tant, researcher, and system devel­oper since 2014.

Take the cow, for example. Critics often portray cattle as climate killers because of their methane emis­sions. But this view is too simplistic since all the green­house gases emitted by cows are based on their feed, which in turn comes from plants that have grown through photo­syn­thesis using carbon dioxide from the atmos­phere. These emis­sions are there­fore biogenic, espe­cially since, according to current scien­tific knowl­edge, this methane breaks down natu­rally again after about 12 years.

This narrow focus on methane emis­sions also over­looks the signif­i­cant biolog­ical achieve­ments cow provide in converting grass, which humans cannot digest, into high-quality food­stuff like milk. Cows are meta­bolic power­house with immense bene­fits for humans world­wide.

Still, these posi­tive aspects should not distract from the need to make cattle farming, and dairy farming in partic­ular, more climate friendly.  As always, there is not just one single solu­tion but rather a suite of approaches at various levels that can shrink the carbon foot­print of meat and dairy produc­tion.

Where are the hidden savings poten­tials?

Agri­cul­tural expert Helmut Döhler empha­sises one aspect in partic­ular in that the animal species, in his view, with the highest emis­sions deserve closer scrutiny. The aim is not to argue for elim­i­nating cattle farming, but to deter­mine scien­tif­i­cally which breeds perform best from a climate perspec­tive. He favours multi-purpose breeds over highly specialised, dairy breeds because he believes they offer advan­tages in overall emis­sions balance.

Addi­tional reduc­tion poten­tial lies in ensiling, feeding, barn design, and slurry storage. These are key topics at the Milk Sustain­ability Center, founded by DeLaval and John Deer, which focuses on improving effi­ciency, sustain­ability, and ulti­mately an opti­mised carbon foot­print.

There is still much to be done: according to the Federal Envi­ron­ment Agency, German agri­cul­ture still emits around 62 million tonnes of carbon dioxide equiv­a­lents per year in the form of carbon dioxide, methane, and nitrous oxide into the atmos­phere, which corre­sponds to approx­i­mately 9.6 per cent of Germany’s total emis­sions. If land use changes are included, such as the draining of peat­lands, the figure is as high as 100m tonnes, which accounts for around 14 per cent of total green­house gas emis­sions.  

Climate-neutral on paper

Organic farming also offers promising oppor­tu­ni­ties. Compared with conven­tional agri­cul­ture, it emits only around half of the rele­vant green­house gases per hectare. “However, as the yields in organic farming are signif­i­cantly lowerthe green­house gas balance of the respec­tive prod­ucts is ulti­mately similar,” explains Helmut.

Still, he esti­mates that a broader shift to organic produc­tion could reduce CO₂ emis­sions by around one million tonnes if expanded accord­ingly, mainly by avoiding synthetic fertilisers, which require substan­tial energy to produce, and through higher humus content that stores more carbon. There are also major bene­fits for biodi­ver­sity. 

Yet, despite these options, emis­sion-free agri­cul­ture is hardly achiev­able at the present time. “In order to make agri­cul­ture climate-neutral, at least arith­meti­cally, we need to offset unavoid­able emis­sions. We can do this best by providing renew­able energy,” says Helmut.  

“Besides wind and hydropower as well as photo­voltaic systems for gener­ating elec­tricity and hydrogen, we have a wide range of options for producing biogas for flex­ible, demand-based elec­tricity feed-in as well as for producing biofuels and supplying rural areas with green heat.” In addi­tion, oil crops also contribute to renew­able fuel options.

Utilizing manure: Many live­stock farms already operate on-site biogas plants using only residual mate­rials.

Research at the Berge exper­i­mental station labo­ra­tory in Bran­den­burg: Exper­i­ments in mini-fermenters.

Bioen­ergy supports the climate tran­si­tion

Danish process chemist Anker Jacobsen shares the same perspec­tive. A pioneer in sepa­rating biogas into biomethane and carbon dioxide via amine scrub­bing, he sees bioen­ergy as essen­tial to achieving a climate-neutral economy.  “However, I crit­i­cise the IPCC’s current calcu­la­tion methods because they simply misjudge the signif­i­cance of biogenic CO₂” he says.  

Anker calls for a scien­tific reassess­ment of plant based versus fossil-based CO₂ and asks funda­mental ques­tions. How does carbon circu­late in natural and man-made cycles? How does this actu­ally affect the climate? His argu­ment is that new calcu­la­tion models are needed to advance the energy tran­si­tion and better agriculture’s posi­tive climate contri­bu­tions. This is by no means without conflict, he acknowl­edges, , since the objec­tives of climate protec­tion and envi­ron­mental protec­tion often clash. However, he believes that these conflicts can be resolved.

For Anker, biogas from agri­cul­tural residues is espe­cially impor­tant because it offers ’green’ carbon with renew­able elec­tricity. This is because the CO₂ sepa­rated from the biogas can react with hydrogen from wind and solar-powered elec­trol­ysis to produce e-methanol (CH₃OH), for example, which can be used as large-scale fuel for maritime ship­ping.  

Fertil­i­sa­tion, drones, emis­sion reduc­tion

Real­ising these oppor­tu­ni­ties will require exten­sive local agri­cul­tural research – not only in barns and fermenters but also in fields across diverse regions. The value of such research is evident at the agri­cul­tural exper­i­mental in Berge, n near Nauen in Brandenburg’s Havel­land district.

There, Dr Andreas Muskolus and his team have been conducting impres­sive research there for many years to provide new guid­ance on adapting agri­cul­ture to changing climatic condi­tions. At the tradi­tional test facility – whose former director Dr Fritz Klatt, published the ahead of its time hand­book Field Irri­ga­tion and Its Proper Use in 1951, current research explores new fertil­i­sa­tion tech­niques, drone appli­ca­tions in arable farming, and strate­gies for reducing climate-damaging emis­sions.

“One thing is absolutely clear. I don’t want to convey an apoc­a­lyptic mood, but we can’t continue farming the way we are”, states Andreas during a tour of the test facility, which is part of the Insti­tute of Agri­cul­tural and Urban Ecolog­ical Projects (IASP) at Humboldt Univer­sity in Berlin.

Among other initia­tives, his team are working on a project titled ‘GEWINN’, awarded by the Agency for Renew­able Resources (FNR), which inves­ti­gates how methane emis­sions from applying fermen­ta­tion residues can be reduced and even harnessed for energy.  

The methane yield is expected to increase by ten per cent. Although this margin is still theo­ret­ical, the demon­stra­tion system installed a container in Berge will soon provide reli­able data.  “We extract ammonia from the fermen­ta­tion residue at half a bar nega­tive pres­sure and add caustic soda and heat so that the long-chain hydro­car­bons are broken down and the methane bacteria can convert more”, says Fabian Kraus, project manager at the Berlin Centre of Compe­tence for Water.”