Farm-scale biogas production in Finland
Author: Hanna Joronen
Edited by: Hasan Md Mahmadul
Biogas production at farms - basic idea
Biogas is produced in shortage of oxygen from the biomass by anaerobic bacteria. Manure biomass is a complex combination of hydrocarbons - carbohydrates, proteins and lipids (Figure 1). Also, the crop residues can be used for biogas production. Biomass is kept in the digesting tank for about 25 days at 37 C. The end product, the biogas consists mainly of methane and carbon dioxide. Some carbon monoxide, sulphur compounds, nitrogen and hydrogen are also produced in the process. The quality of the gas depends on the raw material. Basically, the raw material which contains a lot of easily decomposed organic matter and not too much water, produce gas more effectively. From 1000 kilograms of cattle manure, one can get about 25 m^3 of biogas.
Gas can be used for heat production in gas boilers or for the production of electricity in the gas engine. Among the gas, some solid matter is left after the process. With biogas production, farms can create heat and power for their own purposes. Gas can also be further refined for agricultural machinery. (Motiva Oy).
Farmers can benefit from the biogas reactor plant investment. First of all, with biogas production, they can make a farm almost self-sufficient in heat and power production. This can be a tempting option especially for dairy farms which have the high demand for electricity (Lindholm 2017). In addition to the increased self-sufficiency, the biogas production from the manure and other waste decreases the odor nuisance from the manure. Digested solid matter is also a better fertilizer for the fields as plants can use the nutrients more efficiently. The spreading costs of the sludge are also decreased. (Motiva Oy).
There are some challenges in producing biogas in a Finnish farm as well. First of all, the production plant is a big invest and to some extend the markets are under-developed (Mutikainen et. al 2016). The technology of the process is not yet at its highest possible level (Mutikainen et. al 2016, Masse et. al 2011). Also, the storage of biogas is difficult (Mutikainen et. al 2016).
Figure 1. Basic idea of the biogas production from manure (Masse et al. 2011).
Farm-scale biogas markets
The greatest potential in biogas production in Finland is related to the minor flows and the remainders of the farms. The potential of the farm-scale biogas production is estimated as high as 4 TWh (Biokaasuyhdistys). This estimation does not include the agrobiomass produced on the fields dedicated to the biomass production but only manure and crop residues.
In 2017, there were 16 operating farm-scale biogas reactors in Finland (Huttunen et al. 2018). The amount of energy production in 2017 was about 1 TWh. In ten years, from 2007 and 2017, there can be seen a more than three-fold increase in biogas utilization at farms (Figure 2.)
Figure 1.Production and utilization of biogas in farm-scale reactor plants in Finland 1994-2017. Lower part of column represents utilization, upper part surplus combustion. (Huttunen et. al 2018)
Description of the policy measures
There is an investment grant of 35 % of the acceptable costs for farmers which are investing to energy production from the renewable materials (Finlex Data Bank). The government guarantees the loans for energy production investments up to 500 000 € (Finnish Food Authority). The business plan must be included in the application. The investment is valid for the subsidy as long as the energy is used at the farm for own purposes and 10 % of the heat is consumed at the farm. The decision of the financing must be published before the construction of the production plant can be started (Manner-Suomen maaseudun kehittämisohjelma 2014-2020).
In some cases, the surplus electricity can be sold to the national power-distribution network at the price of feed-in tariff (Lindholm). The subsidy of 9,36 million euros was recently granted to the so far biggest biogas project in Finland. The decomposed material which consist mostly of manure from the near farms is approximated to be from 100 000 to 150 000 tons per year (Kyytsönen).
Evaluation of the effect of these measures
Investments on the biogas production have clearly increased since 1980. There might be some positive effects on the investments because of the investment grants. It, however, seems that the markets of farm-scale are not at its full potential. Some further policy measurements - and time - will be needed. Especially, the possibility of selling out the produced electricity and heat would require more attention from the politicians.
One of the most important issue what encourage farmers to invest in biogas is that they see successful examples. Nowadays, the farming subsidy and license systems are quite complex – it would need some clarification in order to be more efficient.
It is clear that only a viable company can invest in biogas production. Biogas plants are not very cheap ones – hundreds of thousands of euros must be put into the plant. The future of the market development depends on the general development of agriculture in Finland, too. If the domestic primary producers are economically profitable, they can naturally invest more.
Despite of possibility of refining biogas for machinery, usage of biogas in agricultural machines is quite low in Finland. There are some biogas-driven machines in Finland which have transformed from diesel-driven to biogas-driven ones (Kemppainen 2014). Supporting biogas-driven machinery would also increase interest towards farm-scale biogas production as then the fuel costs would also decrease.
Biokaasuyhdistys - Finnish Biogas Association. Biokaasu ja maatilat. [Cited: 24.1.2018]. Available: http://www.biokaasuyhdistys.net/tietoa-biokaasusta/biokaasu-ja-maatilat/
Energiavirasto - Finnish Energy Authority. 2019. Tuotantotuki. [Cited: 20.1.2019] Available: https://www.energiavirasto.fi/tuotantotuki1
Finlex Data Bank. 241/2015. Valtioneuvoston asetus maatilan investointituen kohdentamisesta.[Cited: 20.1.2019]. Available: https://www.finlex.fi/fi/laki/alkup/2015/20150241
Huttunen, M., Kuittinen, V. & Lampinen A. 2018. Suomen biokaasulaitosrekisteri n:o 21. Publications of the University of Eastern Finland. Reports and Studies in Forestry and Natural Sciences. No 33. Available: http://urn.fi/URN:ISBN:978-952-61-2856-6
Jouko Kyytsönen. Suomen suurin kaasulaitos Nurmoon – tuottaa lähimaatilojen karjanlannasta biokaasua autoille. Maaseudun tulevaisuus 18.12.2018. Available: https://www.maaseuduntulevaisuus.fi/talous/artikkeli-1.349495
Kemppainen, J. 2014. Biokaasulla toimiva traktori. 41 p. Available: https://www.theseus.fi/bitstream/handle/10024/74601/Kemppainen_Jaakko.pdf?sequence=1
Kymäläinen M. & Pakarinen, O. 2015. Biokaasuteknologia – raaka-aineet, prosessointi ja lopputuotteiden hyödyntäminen. Suomen biokaasuyhdistys ry.
Lindholm, K. Biokaasu teki maatilasta lähes sähköomavaraisen. Maaseudun tulevaisuus 6.12.2017. [Cited: 20.1.2019] Available: https://www.maaseuduntulevaisuus.fi/suomalainen-maaseutu/artikkeli-1.216404
Manner-Suomen maaseudun kehittämisohjelma 2014-2020. Investointituista menestyksen eväitä maatiloille. Available: https://www.ruokavirasto.fi/globalassets/viljelijat/tuet-ja-rahoitus/investointituet-2014-2020.pdf
Massé, D.I., Talbot, G. & Gilbert, Y. 2011. On farm biogas production: a method to reduce GHG emissions and develop more sustainable livestock operations. Animal Feed Science and Technology 166-167:436-445.
Motiva Oy. 2013. Biokaasun tuotanto maatilalla. Available: https://www.motiva.fi/files/6958/Biokaasun_tuotanto_maatilalla.pdf
Mutikainen, M., Sormunen K., Paavola H., Haikonen, T. & Väisänen, M. 2016. Sitran selvityksiä 111 – Biokaasusta kasvua: Biokaasuliiketoiminnan ekosysteemien mahdollisuudet.
Ruokavirasto - Finnish Food Authority. Maatalouden investointituet. [Cited: 20.1.2019]. Available: https://www.ruokavirasto.fi/viljelijat/tuet-ja-rahoitus/maatalouden-investointituet/