Classification
EHA - Renewable energy sources
6
ENA - Energy from biomass and waste
2
CNW - Electrochemical energy production and conversion
1
EBA - Energy production, energy technology
1
EIA - Solar energy - general
1
EIS - Solar cells
1
EKA - Wind energy
1
EMA - Hydroelectric, tidal energy
1
ESB - Hydrogen energy
1
ETA - Energy storage
1
UHCH - Urban areas
1