Post offices in Singapore have all been certified as being "green" by the Singapore Environment Council.
Singapore Post saw its first ever decline in letter mail volumes last year, as profits fell by 4% year-on-year.
SingPost has invested S$45m ($36.4m USD) to upgrade its mail sorting machinery to speed up processing, improve productivity and service quality.
Singapore Post - known as SingPost - is the national postal operator in Singapore, providing mail, logistics and retail services in Singapore and beyond.
Singapore Post has launched its trial offering 24-hour "smart" lockers as an alternative delivery point for parcels.
SingPost is launching a S$10m ($8m USD) "Inclusivity Fund" to help lower income staff cope with the rising cost of living.
SingPost has seen its profits drop 5.1% in the last three months of 2012, as its mail business declined for a fifth consecutive quarter.
Canada Post Group is the Crown corporation operating the universal postal service in Canada.