The energy consumption
of self-propelled balers was higher than the other collection machines because they moved on rubber-chain wheels.
For a better comparison of balers and the gathering machine on energy balance and cost, an assessment that includes
subsequently compressing loose straw into bales should be done.
In comparison with manual collection, the energy consumption of
mechanized balers, which is mainly from fossil fuels, causes an
adverse impact. However, assuming that rice straw is collected
and used for biogas production, this range of energy consumption
(317–721 MJt−1) only accounts for 10–17% ofthe total input energy
of rice straw anaerobic digestion, which generated a net energy of
3500 (±160) MJt−1 of straw (Nguyen et al., 2016).