The article describes the design phase, development and practical application of a smart object integrated in a desk lamp and called “Smart Lamp”, useful to optimize the indoor thermal comfort and energy savings that are two important workplace issues where the comfort of the workers and the consumption of the building strongly affect the economic balance of a company. The Smart Lamp was built using a microcontroller, an integrated temperature and relative humidity sensor, some other modules and a 3D printer. This smart device is similar to the desk lamps that are usually found in offices but it allows one to adjust the indoor thermal comfort, by interacting directly with the air conditioner.
After the construction phase, the Smart Lamp was installed in an office normally occupied by four workers to evaluate the indoor thermal comfort and the cooling consumption in summer. The results showed how the application of the Smart Lamp effectively reduced the energy consumption, optimizing the thermal comfort. The use of DIY approach combined with read-write functionality of websites, blog and social platforms, also allowed to customize, improve, share, reproduce and interconnect technologies so that anybody could use them in any occupied environment.
SMART LAMP, HARDWARE AND SOFTWARE
The construction of smart lamp has required a series of adjustments and manufacturing of two distinct cases: the housing for the installation of the LED panel and the infrared emitter and a new base in which the elements described above are integrated. Both cases are designed in 3D CAD format and printed with a 3D printer with PLA. The new lamp housing (Figure 2) has the same shape as the original one and provides the fixing of LED panel with screws on the back.
The new base (Figure 3) consists of a flat cylinder with an internal subdivision in blocks. The biggest central block is equipped with a removable drawer allowing the maintenance of the electronic devices.
SMART LAMP INSTALLATION
The Smart Lamp was installed in an office located on the first and top floor of about 42 m normally occupied by four users. The office (Figure 6) is equipped with a HVAC system. Three integrated air temperature and relative humidity sensors (RHT), equally distributed along the 7.81 m long side, a globe thermometer (G) and an energy counter (C) ABB OD 1365 were installed, all connected to a data logger (D): the environmental variables were detected every 10 s and averaged every minute.
EXPERIMENTATION: RESULTS AND DISCUSSION
The daily average consumption related to the automatic control is equal to 13.96 kWh with an average external temperature equal to 29.91°C (standard deviation of 0.87 kWh and 1.69°C, respectively). With manual control, the daily average consumption is equal to 14.97 kWh with an average external temperature equal to 30.30°C (standard deviation of 2.2 kWh and 1.64°C, respectively). The area of the spheres of Figure 9 represents the percentage variation of the daily cumulative consumption compared to the mean value of the period.
The system, implemented following the DIY philosophy and the use of open hardware and low-cost sensors, allows the indoor thermal comfort to be independently managed. This automatic DIY HVAC control system is an extremely flexible solution. The analysis conducted so far demonstrates how it is possible to optimally manage the indoor thermal comfort and energy consumption because the Smart Lamp, manufactured using a desk lamp, some electronics components and two 3D printed cases, interacts directly with the HVAC system wireless through the IR LED. The hardware and software architecture based on Arduino board and the information for the 3D printer are available for download through website so it is easy to replicate and to customize this solution to specific needs.
The Smart Lamp project is implemented in the field of the Internet of Things for the built environment. The potential of this basic device is confirmed by tests in real working conditions. The characteristics so far described and analysed allow a wide field of application aimed at improving users satisfaction and energy consumption of buildings. Current researches are focus on the interaction between the thermal comfort quality and the personal control of users, showing how the micro-climatic conditions play a fundamental role in users satisfaction. Thanks to the easy reproducibility and application the Smart Lamp could be applied to manage the punctual micro-climatic conditions of a single workplace improving the indoor quality.
Authors: Francesco Salamone | Lorenzo Belussi | Ludovico Danza | Matteo Ghellere | Italo Meroni