Addressing Biogenic Greenhouse Gas Emissions from Hydropower in LCA
- 2 August 2013
- journal article
- Published by American Chemical Society (ACS) in Environmental Science & Technology
- Vol. 47 (17), 9604-9611
- https://doi.org/10.1021/es401820p
Abstract
The ability of hydropower to contribute to climate change mitigation is sometimes questioned, citing emissions of methane and carbon dioxide resulting from the degradation of biogenic carbon in hydropower reservoirs. These emissions are, however, not always addressed in life cycle assessment, leading to a bias in technology comparisons, and often misunderstood. The objective of this paper is to review and analyze the generation of greenhouse gas emissions from reservoirs for the purpose of technology assessment, relating established emission measurements to power generation. A literature review, data collection, and statistical analysis of methane and CO2 emissions are conducted. In a sample of 82 measurements, methane emissions per kWh hydropower generated are log-normally distributed, ranging from micrograms to 10s of kg. A multivariate regression analysis shows that the reservoir area per kWh electricity is the most important explanatory variable. Methane emissions flux per reservoir area are correlated with the natural net primary production of the area, the age of the power plant, and the inclusion of bubbling emissions in the measurement. Even together, these factors fail to explain most of the variation in the methane flux. The global average emissions from hydropower are estimated to be 85 gCO2/kWh and 3 gCH4/kWh, with a multiplicative uncertainty factor of 2. GHG emissions from hydropower can be largely avoided by ceasing to build hydropower plants with high land use per unit of electricity generated.This publication has 49 references indexed in Scilit:
- Climate effects of the Three Gorges Reservoir as simulated by a high resolution double nested regional climate modelQuaternary International, 2012
- Renewable EnergyPublished by Cambridge University Press (CUP) ,2012
- Greenhouse-gas emissions from tropical damsNature Climate Change, 2012
- Life cycle assessment of a community hydroelectric power system in rural ThailandRenewable Energy, 2011
- Life cycle greenhouse gas (GHG) emissions from the generation of wind and hydro powerRenewable and Sustainable Energy Reviews, 2011
- GHG emissions from hydroelectric reservoirs in tropical and equatorial regions: Review of 20 years of CH4 emission measurementsEnergy Policy, 2011
- Life cycle assessment of mini-hydropower plants in ThailandThe International Journal of Life Cycle Assessment, 2011
- Life cycle assessment of electricity generation in MexicoEnergy, 2011
- A benchmark for life cycle air emissions and life cycle impact assessment of hydrokinetic energy extraction using life cycle assessmentRenewable Energy, 2011
- Life-cycle inventory for hydroelectric generation: a Brazilian case studyJournal of Cleaner Production, 2010