# Biomass combustion and CHP: Impact on the biosphere

The smoke behind millions of early deaths each year

Source page: https://www.materialinsights.org/energy/e_bio_combustion/biosphere/

What this tab covers Effects on human, animal, plant, fungal and microbial life and on whole ecosystems: in the short term (construction and early years), medium term (operating life) and long term (decommissioning and legacy).

The largest effect by far is on human health: smoke from household fires and stoves causes about 3.2 million premature deaths a year. Large-scale combustion's main ecological effect is the land needed to grow fuel.
 Premature deaths from household air pollution about 3.2 million a year^[7](https://www.who.int/teams/environment-climate-change-and-health/air-quality-and-health/sectoral-interventions/household-air-pollution/health-risks) Deaths per TWh, biomass electricity (accidents and air pollution) 4.6^[17](https://ourworldindata.org/grapher/death-rates-from-energy-production-per-twh) People relying mainly on polluting fuels about 2.1 billion^[7](https://www.who.int/teams/environment-climate-change-and-health/air-quality-and-health/sectoral-interventions/household-air-pollution/health-risks) Land use, biomass electricity (median) 58,000 ha per TWh a year^[12](https://doi.org/10.1371/journal.pone.0270155) Life-cycle emissions, dedicated biomass power 130-420 g CO2eq/kWh (median 230)^[10](https://www.ipcc.ch/site/assets/uploads/2018/02/ipcc_wg3_ar5_annex-iii.pdf)^[11](https://www.stet-review.org/articles/stet/full_html/2024/01/stet20240201/T8.html)

#### Effects over time

| Life affected | Short term | Medium term | Long term |
|---|---|---|---|
| **Humans**^[7](https://www.who.int/teams/environment-climate-change-and-health/air-quality-and-health/sectoral-interventions/household-air-pollution/health-risks)^[17](https://ourworldindata.org/grapher/death-rates-from-energy-production-per-twh) | Burns and scalds from open fires and unstable stoves, especially among children. | Household air pollution causes about 3.2 million premature deaths a year: 32% from ischaemic heart disease, 23% stroke, 21% lower respiratory infections, 19% COPD and 6% lung cancer, and almost half of pneumonia deaths in children under 5. For biomass power, accidents and air pollution cause about 4.6 deaths per TWh. | Switching to cleaner stoves or fuels removes the exposure; the disease burden falls over years as lungs and hearts recover. |
| **Animals**^[12](https://doi.org/10.1371/journal.pone.0270155) | Habitat disturbance where forests are cut for fuel. | Little quantified evidence in the sources reviewed; effects depend on whether fuel comes from residues or standing forest. | Little evidence of effect where harvesting stays within regrowth. |
| **Plants**^[12](https://doi.org/10.1371/journal.pone.0270155) | Removal of trees and shrubs around settlements and charcoal kilns. | Biomass grown for power uses a median 58,000 ha per TWh a year, the most of any electricity source studied. | Forests regrow if harvest stays within growth; otherwise woodland is degraded. |
| **Fungi and soil life**^[12](https://doi.org/10.1371/journal.pone.0270155) | Little evidence of effect in the sources reviewed. | Little evidence of effect in the sources reviewed. | Little evidence of effect in the sources reviewed. |
| **Ecosystems**^[13](https://research.utwente.nl/en/publications/the-water-footprint-of-bioenergy-and-other-primary-energy-carrier/)^[8](https://eur-lex.europa.eu/eli/dir/2018/2001/oj) | Water drawn by fuel crops: biomass needs 70 to 400 times more water per unit of energy than other primary energy sources (excluding hydropower). | Carbon released on burning is reabsorbed only as replacement plants grow; for electricity, EU default values give forest-residue chips 87% savings (89% typical) but gas-heated pellets as little as 24% (37% typical). | Net climate benefit depends on regrowth and on whether residues would otherwise have rotted. |

#### How the effects are reduced

The largest health gain is moving households from open fires to cleaner stoves or fuels (LPG, biogas, electricity); ISO/TR 19867-3 tiers rate stoves on efficiency, carbon monoxide and fine particles. Using residues rather than whole trees keeps land use near 130 rather than 58,000 ha per TWh a year. Powering pellet mills with wood-fired CHP instead of natural gas and grid power raises EU default savings for pellet electricity from 24% to 85%. Filters and electrostatic precipitators control particulates from larger boilers.

#### Sources

1. [Household air pollution: health risks](https://www.who.int/teams/environment-climate-change-and-health/air-quality-and-health/sectoral-interventions/household-air-pollution/health-risks) World Health Organization, 2024
2. [Directive (EU) 2018/2001 (Renewable Energy Directive II), Annex VI: typical and default greenhouse gas savings for biomass fuels and biogas; fossil comparators 183 g CO2eq/MJ (electricity), 80 (heat), 94 (biomethane). Default values not changed by amending Directive (EU) 2023/2413 (RED III); a Commission revision of Annexes V and VI was in draft in 2026](https://eur-lex.europa.eu/eli/dir/2018/2001/oj) European Union (EUR-Lex), 2018
3. [Annex III: Technology-specific cost and performance parameters, Table A.III.2 (Schlomer et al.), in Climate Change 2014: Mitigation of Climate Change (AR5 WGIII)](https://www.ipcc.ch/site/assets/uploads/2018/02/ipcc_wg3_ar5_annex-iii.pdf) IPCC, 2014
4. [4E analysis of solar photovoltaic, wind, and hybrid power systems in southern Pakistan (Yousuf, Malik and Umair), Table 8 reproducing IPCC life-cycle emissions](https://www.stet-review.org/articles/stet/full_html/2024/01/stet20240201/T8.html) Science and Technology for Energy Transition (STET Review), 2024
5. [Land-use intensity of electricity production and tomorrow's energy landscape (Lovering, Swain, Blomqvist and Hernandez)](https://doi.org/10.1371/journal.pone.0270155) PLOS ONE, 2022
6. [The water footprint of bioenergy and other primary energy carriers (Gerbens-Leenes, Hoekstra and van der Meer, Value of Water Research Report 29)](https://research.utwente.nl/en/publications/the-water-footprint-of-bioenergy-and-other-primary-energy-carrier/) UNESCO-IHE / University of Twente, 2008
7. [Death rates per unit of electricity production (biomass figure from Markandya and Wilkinson, The Lancet 2007)](https://ourworldindata.org/grapher/death-rates-from-energy-production-per-twh) Our World in Data, 2022

## Other sections

- [Summary](https://www.materialinsights.org/energy/e_bio_combustion/index.md)
- [Overview](https://www.materialinsights.org/energy/e_bio_combustion/overview/index.md)
- [Correlation](https://www.materialinsights.org/energy/e_bio_combustion/correlation/index.md)
- [Efficiency](https://www.materialinsights.org/energy/e_bio_combustion/efficiency/index.md)
- [Techniques](https://www.materialinsights.org/energy/e_bio_combustion/techniques/index.md)
- [Resources and labour](https://www.materialinsights.org/energy/e_bio_combustion/resources/index.md)
- [Relationships](https://www.materialinsights.org/energy/e_bio_combustion/links/index.md)