I think you might want to consider non-renewable energy sources, non-recyclable ...

		zarify on July 18, 2014 \| parent \| context \| favorite \| on: The UN thinks we could hit peak births in 2014 I think you might want to consider non-renewable energy sources, non-recyclable waste and so on before throwing words like 'equilibrium' around :) I get that it's in the context of population though.