Energy Efficient Thermal Comfort Control for Residential Building Based on Nonlinear EMPC

For purpose of achieving the desired thermal comfort level and reducing the economic cost of maintaining the thermal comfort of green residential building,an energy efficient thermal comfort control strategy based on economic model predictive control(EMPC)for green residential buildings which adopts household heat metering is presented.Firstly,the nonlinear thermal comfort model of heating room is analyzed and obtained.A practical nonlinear thermal comfort prediction model is obtained by using an approximation method.Then,the economic cost function and optimization problem of energy-saving under the necessary thermal comfort requirements are constructed to realize the optimal economic performance of the dynamic process.The energy efficient thermal comfort MPC(EETCMPC)is designed.Finally,the comparison and analysis between EETCMPC and Double-layer Model Predictive Control(DMPC)is simulated.The simulation results reveal that when the clothing insulation is typical,the energy efficiency of EETCMPC is 8.9%and 11.6%,respectively,in the two simulation scenarios.When the clothing insulation varies with temperature,the energy efficiency of EETCMPC is 7.29%and 9.15%,respectively,and the total energy consumption is reduced by about 1.65%and 14.6%,respectively,compared with the typical clothing insulation.The economic performance is improved in the thermal comfort dynamic process of heating room.

Does back cooling improve human thermal comfort in warm environments?A device for heat conduction by the semiconductor Peltier effect

The hot environment and the metabolic heat of commuting in summer caused individual overheating and intense thermal discomfort.Local cooling presents huge potential for optimizing thermal comfort.This study investigates the performance of a back cooling device,based on the semiconductor Peltier effect,in improving thermal comfort after summer commuting.We studied one case without cooling,and three cases with surface temperatures of the cooling device of 29,27,and 25℃using a simulated summer commute at a moderate activity level.The results showed that thermal sensation,perceived sweating rate,and skin temperature decreased markedly in the cooling cases compared to the non-cooling case,with the changes being most notable in the lower back,in contact with the cooling device.The decrease in overall thermal sensation and mean skin temperature was approximately 0.52 score and 0.31℃on average,respectively,with a 1.71 score increase in overall thermal comfort.We contend that the surface temperature of local contact cooling devices should not be lower than 22℃to minimize local overcooling.Back cooling devices present a huge potential for building energy-savings at ambient air temperature exceeding 30℃.Moreover,the functional paradigms for individual comfort predict improved comfort performance in future applications.This study contributes to the understanding on the well-being and physiological recovery of individuals after a summer commuting.