Environmental and economic assessment of integrated systems for dairy manure treatment coupled with algae bioenergy production

► Life cycle assessment (LCA), costing (LCC) of four dairy manure management options. ► Reference (REF) exhibits net energy consumption, negative net present value (NPV). ► Digestion with/without algae cultivation yields net energy production, positive NPV. ► Nutrient credits are critical to financial tenability of LCA-preferred options.