Alternative & renewable energy sources & technology Energy technology & engineering 7 Electrical engineering 3 Sustainability 3 Economics 2 Environmental science, engineering & technology 2 Business & the environment, 'Green' approaches to business 1 Civil engineering, surveying & building 1 Communications engineering / telecommunications 1 Economic geography 1 Energy 1 Energy conversion & storage 1 Environmental management 1 Ethics & moral philosophy 1 Higher & further education, tertiary education 1 Information retrieval 1 Marine engineering 1 Mechanical engineering 1 Political economy 1 Production engineering 1 Study & learning skills: general 1 Thermodynamics & heat 1