Every night at RIT I would walk by closed computers labs, but to my amazement the computer and monitors remained powered on. As an institution that promoted its sustainable practices, not turning the computers off when the labs were closed seemed hypocritical. Every year students would complain about this issue, but nothing was ever done. My roommate, Ian Mikutel, and I decided that we would do something about RIT not having a computer power policy.

Ian and I met with the Chief Technology Officer of RIT, and she agreed that the idea of either turning computers off or having them sleep when they were not utilized was a great idea. We pursued the idea further and started meeting with ITS, the organization that managed a majority of the RIT computer labs and FMS, which was responsible for providing electricity to the buildings. Ian and I decided to implement an actually computer lab trial to demonstrate that a computer power policy could be successfully implemented and to measure the power savings. After many meetings we decided that putting the computers into S3 sleep mode after 20 minutes was the best way to maximize student productivity while minimizing power consumption. Having the computers sleep instead of turning them off ensured that computers would still receive security updates and patches in the middle of the night.

FMS installed a power meter to monitor the power consumption of the 16 Dell desktop computers in the lab. This allowed us to quantize the power savings of having the computers automatically sleep after 20 minutes. After modifying some files and fixing a couple configuration issues the computers automatically went to sleep and automatically awoke in the middle of the night to install security updates. We monitored the power consumption for around 10 weeks, and discovered that having the computers sleep reduced the labs power consumption by 66%! Everyone working on the project was amazed at the results, and when we extrapolated this to the thousands of computers at RIT, the environmental and monetary impacts are massive. Ian and I presented to the RIT’s Committee on Sustainable Practices which was very impressed with our presentation and decided to begin implementing computer sleep mode across campus. Ian and I have both recently graduated so we will not see the end results of our work, but we are both extremely proud to have made such a difference in reducing the power consumption across RIT.

The Purist solar hot water pump and controller has some cool software which logs and graphs the performance of the system. Below is a graph of the performance of the solar thermal system during the day. This information is for the pre-heat tank which then feeds a smaller hot water heater. The pre-heat tank uses solar panels to heat the water from the street which ranges from 40-55F to a much warmer temperature. This allows the water heater to use vastly less energy since it doesn’t have to heat the water as much. On a day like this, the water heater wouldn’t even turn on since the inlet temperature is warmer than the 115F set for the water heater.

The yellow line is the temperate of the water at the top of the tank, the blue line is the temperature of the water at the bottom of the tank, and the red line is the temperature of the solar panels on the roof. During the morning two showers are run, which causes cold water to enter the bottom of the tank. At about 9AM, the solar kicks on and it slowly heats the water until 3PM.