In the transition toward a low-carbon economy, the integration of renewable energy (RE) technologies into industrial systems has become an essential component of sustainable development. In developing countries such as Kenya, where energy-intensive manufacturing sectors rely heavily on costly and carbon-intensive grid electricity, renewable energy adoption presents both a strategic and environmental imperative. This study provides one of the first integrated techno-economic analyses of solar photovoltaic (PV) and battery energy storage systems for industrial-scale application in Kenya’s tea-processing sector. Using data from the Kepchomo Tea Factory, a 680 kW grid-tied solar PV system was modeled and optimized through the National Renewable Energy Laboratory’s REopt platform under three design scenarios: PV only, PV with storage, and an expanded hybrid configuration. Detailed hourly load-matching, financial simulation, and sensitivity analyses on discount rates, degradation parameters, and tariff escalation were conducted to evaluate system robustness and long-term performance over a 25-year project horizon. The results indicate that the optimal configuration—a 1,513 kW PV system combined with a 712 kWh battery—achieves a 35% renewable energy share, reduces CO₂ emissions by approximately 14,387 tonnes, and generates a net present value of USD 1.68 million. Moreover, the levelized cost of energy (LCOE) analysis reveals that the hybrid system is economically competitive with grid electricity under current feed-in tariffs. Beyond site-level benefits, the study contributes a replicable methodological framework for industrial decarbonization, renewable investment appraisal, and policy formulation across sub-Saharan Africa, emphasizing the potential of distributed solar-battery systems to enhance energy security and resilience in emerging economies.