One of the current trends for sustainable energy production is microalgal biofuel. It offers a fast-growing feedstock with high oil yield per land area. The current challenge of microalgal biofuel is in its economic competitiveness, because of its high production costs relative to fossil-based fuels. Unique solutions have been proposed to address this issue. One solution focuses on the integration of its production process with another industrial process, such as integration to sugarcane mills. The integration of microalgal biofuel production to the sugar industry can act as a support for the former to be an attractive investment. Several studies have assessed such integration can lead to reduced fossil fuel dependence and reduced environmental impacts. In this study, we utilize linear programming modeling to generate two optimized designs of an integrated system. Both designs focus on maximizing the revenue of the integrated plant. The latter is designed to maximize the revenue with zero carbon emission. Results yield for the prior design had an increased revenue for the sugarcane mill by 4.23% with a drawback of a 7-fold increase in carbon emission. The latter design is able to achieve zero carbon emission with a reduced revenue of 7.68%. This study aims to provide plant designers a methodology to synthesize and assess the integration of a microalgae biofuel plant with the sugarcane ethanol plant.