Compared to fossil fuels, the use of biomass does not emit additional carbon dioxide into the atmosphere

Bioenergy is obtained from organic matter by burning solid, liquid, or gaseous fuels. Most bioenergy is obtained through the use of various wood fuels (wood chips, pellets, firewood, etc.), less herbaceous biomass (hay, straw, reeds), biogas, biodiesel, or bioethanol. The main advantages of using bioenergy are its renewability, local origin and related security of supply, and controllable use.

Bioenergy is an important part of bioeconomy (including the circular economy), where resources are used efficiently and, where possible, repeatedly. Only in the absence of a more profitable use alternative is a resource of biological origin used to produce renewable energy. [1] The environmentally friendly stockpiling of biomass for bioenergy production (e.g. location, volume, and methods) is regulated in Estonia by the Nature Conservation Act and the Forest Act.

Compared to fossil fuels, the use of biomass does not emit additional carbon dioxide into the atmosphere. For example, during growth, plants capture carbon from the atmosphere, which accumulates in the biomass after photosynthesis. During combustion, the captured carbon in the biomass is released and is recaptured during growth. Although the lower calorific value of biomass means that when it is burned, more CO₂ is released into the atmosphere than from fossil fuel combustion to produce the same amount of energy, the carbon released from biomass is the kind that was in the atmosphere years to decades ago and which was captured into the biomass by the growing trees. This means that the carbon cycle for biomass is relatively short-lived, especially compared to fossil fuels. Therefore, in the long run, the recycling of new and additional CO₂ from the burning of fossil fuels cannot be a solution, as it is the cause of climate change. Biomass and the carbon bound in it cannot be stored in the long term and its use for energy or its decaying are relatively equivalent alternatives in terms of CO₂ emissions. [2]

However, a systematic solution for the environmentally friendly use of the resulting ash is not yet in place for the full functioning of the circular bioeconomy (waste minimisation and recovery). There are also a number of challenges related to biofuels, i.e. fuels used in transport:

• the extensive replacement of rainforests with oil monocultures, such as oil palm plantations;
• the partial competition of the first-generation bioethanol and biodiesel production with food production;
• the inferior properties of the first-generation biofuels compared to fossil fuels;
• the costliness of the second-generation fuels compared to fossil fuels.

In addition, bioethanol and biodiesel are not significantly usable in district heating or electricity generation. [3]

All in all, the ever-growing biomass and its products are used to meet different needs. Bioenergy cannot cover all energy needs, but offers a useful and carbon-neutral resource and waste management option. Bioenergy production is thus the last, or, in the absence of alternatives, the main use of the useful life cycle of bioresources in a low-carbon economy.

Last modified: 13.01.2022

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[1] Vahearuanne Eesti biomajanduse ressursside hetkeseisu analüüs 6 väärtusahela põhjal

[2] Anger-Kraavi, A., Pärt, E. jt. Mets ja kliimamuutused. Raport. University of Cambridge. Keskkonnaministeerium.

[3] Niidu, A. 2020. Ettekanne: tulevikukütused