Environmental Impact of Geothermal EneRgy systems
Based on a small number of parameters of a geothermal energy system this code computes the impact of the geothermal energy system to various environmental impact categories. Currently implemented are the models of Paulillo et al. (2022) for conventional (dry steam and flash) and enhanced geothermal systems for power production and Douzciech et al. (2021) for enhanced geothermal systems for heat production. The code is programmed in a way to facilitate the addition of further environmental impact models.
The impact per environmental category is computed with this general equation:
Impact per category = Sum_over_i[(alpha_i * x_i * y_i * z_i**beta_i * 10**(gamma_i * w_i)) / (u_i * v_i) ]
alpha_i, beta_i, gamma_i are coefficients of the models. u_i, v_i, w_i, x_i, y_i, z_i are parameters of the geothermal energy system, e.g. well depth.
Import GeothermalPlant from main. A new instance of a GeothermalPlant can be initialized by choosing the environmental impact model for the plant type e.g. conventional_power_20 for the 20% threshold model for conventional power plants of Paulillo et al. (2022), together with the number of environmental impact categories and parameters of the model:
plant_conv = GeothermalPlant('conventional_power_20',16,10)
A dictionary with parameter values of the geothermal energy system can then be passed to the simple_impact_model function of the geothermal energy system:
parameters = {'operational_CO2_emissions': 0.0209, # kgCO2/kWh
'operational_CH4_emissions': 0.0, # kgCH4/kWh
'producers_capacity': 9, # MW/well
'average_depth_of_wells': 2220, # m/well
'initial_harmonic_decline_rate': 0.03,
'success_rate_primary_wells': 100} # %
category, impact = plant_conv.simple_impact_model(parameters)
The output are two lists, one containing the environmental impact of the geothermal energy system called impact and the second on containing the name of the environmental impact category called 'category'.
The environamental impact models are defined by several tables which are contained in one Excel-file per model. There are tables for alpha_i, beta_i, gamma_i, u_i, v_i, w_i, x_i, y_i, z_i for each environmental impact category and valid ranges for the parameters (u_i, v_i, w_i, x_i, y_i, z_i). The name of the environamental impact model is defined by the name of the Excel-file.