<p>To meet the food needs of a growing population, improving resource productivity, particularly energy efficiency, is essential. At the same time, increased use of agricultural inputs—especially fossil fuels and chemical fertilizers—has intensified greenhouse gas (GHG) emissions. Sugar beet is one of Iran’s strategic crops, contributing significantly to national sugar security, with more than 5.1 million tons produced in 2023. This study aimed to assess farm efficiency, optimize energy consumption, and quantify GHG emissions in sugar beet production in Tehran Province, Iran. Data were collected during the 2023 cropping season through structured questionnaires completed by 20 sugar beet farms. Energy use and GHG emissions were evaluated using energy balance analysis, while farm efficiency and optimization potential were assessed using data envelopment analysis (DEA) with an input-oriented variable returns to scale (VRS) model. The average total energy consumption and energy productivity were 54,685.71&#xa0;MJ&#xa0;ha⁻¹ and 0.61&#xa0;kg&#xa0;MJ⁻¹, respectively. Diesel fuel (26.35%), nitrogen fertilizer (23.10%), irrigation water (19.49%), and electricity (12.15%) accounted for the largest shares of energy consumption. Average GHG emissions were estimated at 1,612.3&#xa0;kg CO₂eq ha⁻¹, mainly originating from diesel fuel (51.61%) and electricity (21.02%). DEA results indicated that 13 farms were technically efficient, while 7 farms were inefficient. Optimization results revealed that energy consumption could be reduced by 11.32% without yield loss, leading to an 18.22% reduction in GHG emissions and an improvement in energy productivity to 0.68&#xa0;kg&#xa0;MJ⁻¹. These findings highlight the potential of targeted input management, particularly in fertilizer use, irrigation, and mechanization, to enhance sustainability and support energy-saving and emission-reduction policies for sugar beet production in Iran.</p>