Environmental impacts of energy saving actions in an academic building

Abstract

Global warming and climate change effects have been of such impact that several countries around the world are enforcing public policies to mitigate them. Mexico has shown a strong commitment to the environment and rational use of energy, as signed on the General Law for Climate Change (GLCC) and stating, in its second article, the goal of a 30% reduction of greenhouse gases by 2020. To add to this goal, the Hermosillo Institute of Technology is implementing a pilot energy saving program that mixes retrofitting of academic buildings and the implementation of automatic controls for lighting and heating, ventilating, and air conditioning (HVAC). The retrofitting is performed by replacing fluorescent T8 tubes with high efficiency LED T8 tubes in a new arrangement. To increase the energy saving obtained by the retrofitting, a building automation and control system (BACS) has been developed and installed. The BACS is implemented using two different networks, the first one communicates a central control unit with the building control node using a private Ethernet network. Inside the building, the control actions are transmitted using a ZigBee network. The energy savings have been estimated as 4864 kWh/year, representing a 36.42% saving, the environmental and health effects are calculated using emission parameters of the nearest power plant to our site, and the procedure presented in Harvard's Six Cities Study by Dockery. Results show a total CO2eq equivalent to 0.000409% of the national goal. The economic impacts of the carbon social cost and health benefits are $745.26 USD/year and $4017.71 USD/year while the direct billing savings are $3700.56 USD/year, and these results are based on only one building of the campus.