  We outline a realistic energy transition roadmap for Italy, in which the
whole energy demand is met by electricity generated by low cost renewable
energy technologies, namely solar photovoltaic, wind and hydroelectric power.
We assess the amount of extra power and storage capacity to be installed along
with costs, return on investment and payback time. Based on cost, renewable
nature and scalability, storage in energy dense polysaccharides enzymatically
synthesized from carbon dioxide, water and surplus electricity is proposed to
meet the significant storage requirements.
