We recently replaced a monitoring solution that was deployed using an HP Pavilion a6000 desktop computer with the same setup using an ARM-powered MicroPIC. We took the opportunity to calculate the savings in energy cost and this post outlines our findings. We were amazed that the MicroPIC costs only $1.18 more per year powered
on vs. the Pavilion in a plugged-in but powered off state. Total yearly
savings of replacing the Pavilion with a MicroPIC was $83.97.
All watt calculations were made using an accurate digital power meter and not the rating of the power supply. An average US cost estimate of $0.135 per Kwh was used from the Bureau of Labor Statistics from August 2011.
Measurements and Cost Results
MicroPIC (powered on and idle): 4watts
- 0.004 Watts × 8760 hours = 35.04 kWh (kiloWatt-hour) of energy
- 35.04 kWh × $0.135f/kWh = $4.73
HP Pavailion a6000 (plugged in but powered off): 3watts
- 0.003 Watts × 8760 hours = 26.28 kWh (kiloWatt-hour) of energy
- 26.28 kWh × $0.135f/kWh = $3.55
HP Pavailion a6000 (powered on and idle): 75watts
- 0.075 Watts × 8760 hours = 657 kWh (kiloWatt-hour) of energy.
- 657 kWh × $0.135f/kWh = $88.70