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Cement production is considered as one of the most energy consuming industries. Any novel strategy to make cement plants more efficient would increase the annual revenue while significantly reducing local and global emissions. In this paper, an energy audit in a cement plant (Kerman, Iran) is presented in order to introduce more viable potential solutions to push this industry towards a more sustainable status. Various parameters, such as temperature and system dimensions, were measured, and raw materials and product analyses were conducted. Then, using the measured and analyzed data, an energy balance analysis was performed. A novel framework based on a well-known global optimizer algorithm and a multi-criteria decision method is presented for integrated energy optimization. This proposed framework is then tested for the audited cement plant at two major steps. First, an efficient metaheuristic optimization approach is employed to optimize the compounds of clinker to reduce the consumption of energy in the cement industry. Second, a decision-making procedure, namely analytic hierarchy process, is used to make right decisions to reduce energy losses after completing an energy audit program. Results of the present study indicate the effectiveness of the proposed framework based on metaheuristic algorithm and decision-making approach.

The rotor area of a wind turbine must be perfectly perpendicular to the wind to deliver the most efficient performance as a single unit (i.e., yaw angle γ = 0°). When the rotor is misaligned (i.e., γ ≠ 0 ° ), the turbine power production is lower and greater structural loads may occur. However, a beneficial effect of yaw misalignment is that it steers the aerodynamic wake and, consequently, it may reduce wake losses for downstream wind turbines. To quantify and maximize such potential power gains while minimizing power losses, a wind farm with 28 wind turbines is investigated using large eddy simulations (LES). Selected turbines in the front-, mid-, and deep-rows are intentionally misaligned by positive (counter-clockwise) or negative (clockwise) yaw angles of various magnitudes. Consistent with previous studies, positive yaw misalignment angles cause net power gains, whereas negative ones cause net losses. We hypothesize that this is due to the Coriolis effect. Thus, only positive yaw misalignment angles should be considered for wake steering purposes in the northern hemisphere. Also, yawing front-row and deep-row turbines causes the overall power production to increase, while yawing mid-row turbines is not as effective. The most effective yaw misalignment angles are + 20 ° for front-row and + 10 ° for deep-row turbines.