@article{30243,
  keywords = {Life-cycle assessment (LCA), Solar energy, Kerosene, Industrial ecology, LED lighting, Technology Adoption},
  author = {Peter Alstone and Patricia Lai and Evan Mills},
  title = {High Life Cycle Efficacy Explains Fast Energy Payback for Improved Off-Grid Lighting in the Developing World},
  abstract = {<p>The energy intensity of fuel-based lighting is substantial given the paltry levels of lighting service, poor economic outcomes, and exposure to public health risks for users throughout the developing world. There is a great opportunity to reduce fossil energy consumption (and mitigate greenhouse gas emissions) while improving public health and economic outcomes for the poor by encouraging upgrading from fuel-based to rechargeable light-emitting diode (LED) lighting. However, switching to efficient lighting requires up-front investments of energy for manufacturing. This study explores life cycle energy performance in the market for modern off-grid lighting (OGL) products in Sub-Saharan Africa and introduces a new metric, life cycle efficacy, which facilitates comparisons and analysis of life cycle energy performance (light output per unit of embodied plus use-phase energy consumption) for lighting technology systems. Combining field insights on technology adoption dynamics with embodied energy estimates for a range of products available in 2012 shows that OGL energy {\textquotedblleft}debts{\textquotedblright} are {\textquotedblleft}paid back{\textquotedblright} in 20 to 50\&nbsp;days (substantially faster than kilowatt-scale grid-connected solar electricity systems) with energy return on investment ratios from 10 to 40. This stems from greatly improved life cycle efficacy for off-grid LED lighting (\~{}20\&nbsp;lumens/watt [lm/W]), compared to fuel-based lighting (\~{}0.04\&nbsp;lumens/W). Life cycle benefits{\textemdash}not only energy, but also economic and health benefits{\textemdash}depend strongly on product service lifetime (related to quality) and fuel displacement fraction (related to performance). OGL life cycle efficacy increases from longer lifetime and/or improved LED source efficacy lead to better quality and less-expensive lighting available in the developing world with lower energy use than the fuel-based incumbent technology.</p>},
  year = {2014},
  booktitle = {Journal of Industrial Ecology},
  journal = {Journal of Industrial Ecology},
  series = {Journal of Industrial Ecology},
  volume = {18},
  pages = {722-733},
  month = {10/2014},
  doi = {10.1111/jiec.12117},
  language = {eng},
}