Technoeconomics of Commodity Chemical Production Using Sunlight

The economic potential for commodity chemical production using sunlight is examined using a general comparative analysis method. The market values and feedstock prices together with basic thermodynamic constraints are used to evaluate the solar-to-chemical conversion potential for selected products using four different solar conversion pathways. Potential products are compared using several metrics including the net value of products per unit of energy input [$/kWh] and annual value of products per unit of solar exposed area [$/m(2)-year]. Low-volume, high-value chemical products such as iodine and tellurium would provide the greatest economic potential for a solar conversion process whereas high-volume, low-value products including hydrogen and methane would have tremendous challenges in generating sufficient revenue to pay for the required capital costs. Artificial photosynthesis research might be better served if the focus were to be first finding some (or any) reasonably valuable product that could be produced economically using sunlight before attempts are supported to make low-value chemical products such as hydrogen and hydrocarbons.