The Iowa Power Fund Board approved a total of $4.2 million for three energy projects.

Ames-based AmbroZea Inc. was awarded $1.5 million to apply high-protein expression biotechnology to optimize multi-tasking yeast for commercial development in Iowa’s fuel-ethanol industry.

Boone-based Avello Bioenergy Inc. was awarded $2.5 million to help build a demonstration-scale biomass plant.

Des Moines-based Indigo Dawn LLC was awarded $225,000 to help develop a two-story building into an integrated renovation and prototypical site that achieves a 75 percent improvement in energy efficiency over minimum standards.