**Abstract**

Worldwide demand for liquid fuels will increase steadily, but not in the form of CO2-emitting scheme, rather in a renewable and sustainable way. Keywords for the future energy direction must be clean, renewable, and sustainable. Alcohol fuels are again becoming a frequent keyword for clean fuel utilization in connection with mitigation of climate change and clean fuel technology suitable for less-used local energy sources. There are a lot of interests in widening the raw feedstock to lignocellulosic biomass and algae from grain-based raw materials. Using the locally available, underutilized feedstock becomes important for local energy security as well as an option for distributed energy infrastructure.

**Keywords:** alcohol fuel, biomass, bio-ethanol, low-grade feedstock, alternative fuel
