Global warming and tragedy of the commons: Comparative evidence of greenhouse gas emission (CO₂) between efficient and inefficient sesame producers in Jigawa State of Nigeria

Data for this research were elicited from 99 sesame farmers in Jigawa State, Nigeria via multistage sampling technique. Energy efficiency was studied and degrees of technical efficiency (TE), pure technical efficiency (PTE) and scale efficiency (SE) were determined using data envelopment analysis (DEA). Additionally, wasteful uses of energy by inefficient farms were assessed and energy saving of different sources was computed. Furthermore, the effect of energy optimization on greenhouse gas (GHG) emission was investigated and the total amount of GHG emission of efficient farms was compared with inefficient ones. Results revealed that only 9.4% DMUs were technically efficient and the average TE score was 0.624; based on BCC model 34.4% DMUs were identified to be efficient and the mean PTE score was 0.79; while based on scale efficiency only 12.5% DMUs were efficient, and the mean SE score was 0.804. Furthermore it was observed that approximately 38.17% (1505.58MJha⁻¹) of overall input energies can be saved if performance of inefficient DMUs rose to a high level. Comparative results of GHG emissions for efficient farmers and inefficient farmers revealed that the amount of CO₂ emissions in efficient DMUs was less than inefficient DMUs. Moreover, findings inferred that, by energy optimization, total GHG emission can be reduced to an estimated value of 21.87 KgCO₂ eq ha⁻¹. Generally, the application of data envelopment analysis method can improve energy efficiency and GHG emissions in sesame production, significantly.