Here is what I can offer in response to your questions:
1) Bio-diesel production remains an attractive option for alternative fuel production. However, to be economically competitive, this technology requires government subsidy otherwise it will have a negative NPV value.
2) Hydrogen production from biomass is an active research area. However, the cost of hydrogen cleanup to 99.9995% purity (see SAE standards) is costly otherwise this feedstock can poison the PEM fuel cells.
3) Hydrogen production by water decomposition into hydrogen and oxygen is another active research area. My colleague Prof. Dan Nucera at Harvard University wrote a nice paper on the artificial leaf. You can google this paper and it is a good read on this topic,
4) Fuel cells like PEM fuel cells, solid oxide fuel cells, and molten carbonate fuel cells are facing competition from the emerging solid state lithium-ion batteries.
Hope you find these highlights helpful and good luck!
Dear Olusegun D. Samuel. If you are interested in the issue of hydrogen production by a new electrochemical method, which provides high purity of hydrogen production -99.98% and high operating pressure of the generated gases over 20.0 MPa. then look at my articles on ResearchGate.