<p>The results of experimental investigations into the main stages of the life cycle of composite liquid fuels are presented. These fuels are synthesized with a view to solving a set of environmental, economic, energy, and technological problems. The potential feedstock is formed from among industrial and municipal waste, plant components, biomass, esters, fats, waste and industrial process waters. Considering their properties, composite liquid fuels can be used in boiler, gas turbine, propulsion, and other installations. The results of multicriterial analysis of the main environmental, energy, and technical-economic indicators of typical composite liquid fuels are presented. The most promising compositions are identified.</p>