- Lars Broer, Agricultural Research and Testing Institute (LUFA) North-West
- Ewald Grimm, Board of Trustees for Agricultural Engineering and Construction
- Dr. Sabrina Hempel, Leibniz Institute for Agricultural Engineering and Bioeconomy (ATB Potsdam)
- Martin Kamp, North Rhine-Westphalia Chamber of Agriculture
- Prof. Stephan Schneider, Nürtingen-Geislingen University of Applied Sciences
- Sandra Terletzki, North Rhine-Westphalia Chamber of Agriculture
- Dr. Sabine Schütze, North Rhine-Westphalia Chamber of Agriculture
Funding note:
This document was produced as part of the collaborative project ‘Netzwerk Fokus Tierwohl’, funding codes 28N-4-013-01 to 28N-4-013-17, by the ‘Emissions Reduction’ working group of the Animal Welfare Competence Centre for Pigs, and methodologically and didactically adapted by DLG e.V. and FiBL
Deutschland e.V. The joint project of the Chambers of Agriculture and agricultural institutions across all federal states aims to improve the transfer of knowledge into practice in order to make cattle, pig and poultry farms fit for the future in terms of animal-welfare-friendly, environmentally sound and sustainable livestock farming.
The project is funded by the Federal Ministry of Food and Agriculture pursuant to a resolution of the German Bundestag.
All information and advice is provided without any warranty or liability.
Publisher
DLG e.V. Agricultural
Centre
Eschborner Landstraße 122
60489 Frankfurt am Main
FiBL Deutschland e.V. Animal Welfare
Division
Kasseler Straße 1a
60486 Frankfurt am Main
As of: 03/2023
© 2023
Reproduction and transmission of individual text sections, drawings or images (including for the purpose of lesson planning), as well as the provision of this information sheet in whole or in part for viewing or download by third parties, is permitted only with the prior authorisation of the relevant department of the Animal Welfare Competence Centre and DLG e.V., Marketing Division, Tel. +49 69 24788-209, [email protected]
Measures to minimise emissions in pig houses
In pig farming, in addition to gaseous emissions such as ammonia, methane and nitrous oxide, odours and particulate emissions such as dust are also produced, the latter of which may also carry bacteria. These can have a negative impact on the indoor climate, affect human and animal health, harm the environment or cause a nuisance. Examples of adverse health effects include abnormal lung findings in fattening pigs and respiratory diseases in farmers.
There is a risk of confusion between the terms ‘emission’ and ‘immission’. Under the Federal Immission Control Act (BImSchG), emissions refer to air pollution, noise, radiation, bioaerosols and similar substances emitted by a facility (livestock housing). Immission, on the other hand, refers to the impact of pollutants on humans, animals, plants and inanimate objects. A large proportion, around 75% of ammonia emissions from agriculture, is generated by cattle, pig and poultry farming, including the storage and application of farm manure. The reason for the high emissions from livestock farming is that, for example, ammonia is produced when excreted urea comes into contact with faeces.1 To avoid negative impacts on animals, humans and the environment, emissions are to be further reduced in future. To this end, there are various legal and therefore binding requirements that specifically relate to ammonia emissions.
| Type of emission | Source | Cause | Possible effect |
| Odour | Stables and exercise areas, storage facilities for solid and liquid manure and feed | Microbial breakdown of organic matter (e.g. faeces, urine, feed), inherent odour | Odour nuisance |
| Ammonia | Stables and paddocks, storage facilities for solid and liquid manure | Microbial breakdown of urea in excrement | Damage to sensitive plants, eutrophication and acidification of ecosystems due to nitrogen deposition, formation of secondary particles (fine dust) |
| Dust | Stables, feed management | Animal activity, bedding, and the conveying, grinding, mixing and distribution of feed | Health risks due to respiratory diseases and allergies |
Under the NEC Directive (2016), ammonia emissions in Germany must be reduced by 29% between 2005 and 2030. Germany has transposed this directive into national law via the 43rd Federal Immission Control Ordinance in order to meet its international obligations and reduce the contribution of transboundary emissions and harmful environmental impacts.
Anyone wishing to build a large-scale livestock facility today that requires approval under immission control legislation must employ state-of-the-art technology or Best Available Techniques (BAT) to reduce emissions.1 The type of approval, as well as the measures subject to approval and those relating to construction and operation, vary depending on the livestock facility:
- Approval of the livestock facility in accordance with Section 10 of the Federal Immission Control Act (BImSchG) with public participation from 2,000 fattening places, 750 sow places or 6,000 piglet places (so-called G-facilities)
- Approval of the livestock facility in accordance with Section 19 of the Federal Immission Control Act (BImSchG) via a simplified procedure without public participation for facilities with 1,500 or more fattening places, 560 or more sow places, or 4,500 or more piglet places (so-called V-facilities)
The Technical Instructions on Air Quality Control (TA Luft), based on the Federal Immission Control Act (BImSchG), applies to both types of facility mentioned. It sets out requirements for emission reduction in livestock facilities and identifies techniques that can be used for emission reduction in livestock housing as state of the art, which are classified as BAT at EU level. This ‘state of the art’ is not binding for smaller facilities that do not require approval under immission control legislation, i.e. those subject only to planning permission. However, it may be used as a guide in individual cases, for example where emissions need to be reduced to ensure the protection of the neighbourhood or sensitive ecosystems.
For so-called G-installations, the requirements for emission reduction include the use of an exhaust air cleaning system (ARE) to reduce ammonia and dust emissions by at least 70% and odour to such an extent that no raw gas or pig odour is detectable in the clean gas and the concentration is below 500 odour units per m³.
In V-plants, ammonia emissions must be reduced by at least 40% using suitable techniques (Annex 11 of the TA Luft). In addition to so-called process-integrated measures, an exhaust air purification system may also be used, in which at least 60% of the maximum flow rate is purified with an efficiency of 70%. In all cases, and regardless of the technology used, a diet with significantly reduced nutrient content must be ensured.
There are various options available to agricultural businesses for reducing emissions. Farmers can, for example, receive grants through the Agricultural Investment Promotion Programme (AFP) for exhaust air purification systems, manure-urine separation, reduced-size slurry channels, feeding systems for nutrient-reduced phased feeding, and slurry cooling techniques.3
It should be noted that the requirements of the AFP may vary depending on the federal state. Furthermore, funding for existing livestock housing is only available within the retrofitting deadlines set by the TA Luft, and for new buildings only if measures are not prescribed under the TA Luft. Further measures to reduce emissions exist, but may only be applied provided they have equivalent effects in terms of emission reduction. For some measures, a range of practical experience and scientific data is already available, whilst others still require further investigation and optimisation.
But what methods and procedures are available to implement the legal requirements whilst also taking into account the behavioural needs of the animals in their housing environment, and to what extent can they reduce emissions?
