Energy and environmental implications of novel protein production systems

The energy requirements of a number of novel protein production systems are compared, along with an examination of the relevant environmental implications of such systems. It is postulated that energy analysis has a role to play in food policy planning through the trade-off between energy and land. The prospects for single cell protein (SCP) fermentations, leaf protein, fish farming, fish protein concentrate, algal cultivation and hydroponic plant growth systems are evaluated, with special emphasis being placed on the last two. Of the processes investigated, SCP from carbohydrate substrates, algal protein and fish protein seem to hold much promise, while hydroponics could be very significant in areas lacking in arable land. The potential of leaf protein and SCP derived from oil appears to be very limited at present, and will probably never provide a significant contribution to world protein supplies.