Long-term planning of supplying energy for greenhouses using renewable resources under uncertainty

Global climate change and significant population growth highlight the importance of food security through emerging techniques including cultivation in greenhouses. This, in turn, calls for cost effective energy supply approaches to provide the greenhouse conditions appropriate. This study addresses energy supply planning for greenhouse farming with a focus on renewable energies. At first, the optimum exploitation of renewable energy units along with energy storage units is presented in mathematical programming in both modes micro-grid and grid-connected. Then due to uncertainty of the energy received from renewable resources, the scenario-based robust optimization approach is adopted with the purpose of income maximization is in grid-connected mode and minimization of cost in micro-grid mode. Because of significant size of data and calculations, an algorithm is developed and it will be analyzed through sensitivity analysis of parameters on the optimal solution with Makran region in Iran as a case. By comparing the results of different categories of problems in micro-grid mode, it can be seen that the lowest values of the objective function are when the investment cost of CHPs is half the investment cost of solar energy and 4 times the investment cost of batteries. Also in case of simultaneous use of wind and solar equipment in Makran region, the model suggests that wind resources contribute more in energy production than solar resources do. In grid-connected, the results suggest that in the case of equal price of selling to the grid and buying power from it, all of the energy will be consumed in the greenhouse. Also, in cases where the cost of solar and wind power is higher than each other, it would not justify selling energy resource to the grid. •Optimum number of energy units to supply the required energy for greenhouses in both Micro-grid and grid-connected modes.•Considering different types of costs by taking advantage of the NPV concept.•Using the scenario-based robust optimization approach for incorporating uncertainty.•Sensitivity analysis of decision variables in the form of different problems.•Presenting the structure of Meta-heuristic algorithm to resolve the problem on a large scale in the Makran region, Iran.