import matplotlib.pyplot as plt import numpy as np import json import sys import argparse __author__ = 'm3x1m0m' class c_settings_extractor: def __init__(self, fname): with open(fname, "r") as rf: settings = json.load(rf) kilometer_price_ccar = settings["ccar"]["litres_per_kilometer"] * settings["juice_litre_price"] self.labels = [settings["ecar"]["label"], settings["ccar"]["label"]] self.purchase = np.array([settings["ecar"]["price"], settings["ccar"]["price"]]) self.taxes = np.array([settings["ecar"]["taxes"], settings["ccar"]["taxes"]]) self.insurance = np.array([settings["ecar"]["insurance"], settings["ccar"]["insurance"]]) kilometer_price_ecar = ( settings["ecar"]["charging_behaviour"]["percent_home_charges"] * settings["kwh_price_home"] + settings["ecar"]["charging_behaviour"]["percent_commercial_charges"] * settings["kwh_price_commercial"]) / 100.0 self.driving = np.array([kilometer_price_ecar * settings["kilometers_per_year"], kilometer_price_ccar * settings["kilometers_per_year"]]) self.maintenance = np.array([settings["ecar"]["maintenance"], settings["ccar"]["maintenance"]]) self.kilometers = settings["kilometers_per_year"] self.currency = settings["currency"] def get_labels(self): return self.labels def get_purchase(self): return self.purchase def get_taxes(self): return self.taxes def get_insurance(self): return self.insurance def get_driving(self): return self.driving def get_maintenance(self): return self.maintenance def get_kilometers(self): return self.kilometers def get_currency(self): return self.currency class c_ecar_comparator: def __init__(self, fname): self.settings_extractor = c_settings_extractor(fname) def calculate_costs_a_year(self): taxes = self.settings_extractor.get_taxes() insurance = self.settings_extractor.get_insurance() driving = self.settings_extractor.get_driving() maintenance = self.settings_extractor.get_maintenance() return taxes + insurance + driving + maintenance def calculate_costs(self, years, months): months_a_year = 12.0 costs_a_year = self.calculate_costs_a_year() return costs_a_year * (years + months/months_a_year) def calculate_break_even(self): total_costs = self.settings_extractor.get_purchase() months_a_year = 12.0 increment = self.calculate_costs_a_year() / months_a_year months = 0 while total_costs[0] > total_costs[1]: total_costs = total_costs + increment months += 1 kilometers = self.settings_extractor.get_kilometers() * months / months_a_year return [months//months_a_year, months%months_a_year, kilometers] # years, months def calculate_amortization_point(self): y = 0 m = 1 months_a_year = 12.0 # Insurance and taxes need to be payed anyway relevant_costs_a_year = self.settings_extractor.get_driving() + self.settings_extractor.get_maintenance() savings_a_month = (relevant_costs_a_year[1]-relevant_costs_a_year[0]) / months_a_year months_till_amortized = self.settings_extractor.get_purchase()[0] / savings_a_month kilometers = months_till_amortized * self.settings_extractor.get_kilometers() / months_a_year months_till_amortized = np.ceil(months_till_amortized) return months_till_amortized//months_a_year, months_till_amortized%months_a_year, round(kilometers, ndigits=2) def main(): parser = argparse.ArgumentParser(description='This script allows to calculate if an electric car makes sense financially for you.') parser.add_argument('-a','--settings', help='Settings file.', required=True, metavar=('FILENAME')) parser.add_argument('-b','--break_even', help='Calculate the break even point (when the EV becomes cheaper).', action='store_true') parser.add_argument('-c','--amortization', help='Calculate the point in time when the electric vehicle is amortized completely by savings.', action='store_true') parser.add_argument('-d','--savings_per_month', help='Calculate savings per month.', action='store_true') parser.add_argument('-e','--savings_per_year', help='Calculate savings per year.', action='store_true') parser.add_argument('-f','--savings_per_kilometer', help='Calculate savings per 100 kilometers (only driving, no maintenance, taxes or insurance).', action='store_true') parser.add_argument('-g','--plot', help='Visualize costs over one or multiple years.', type=int, metavar=('YEARS')) args = parser.parse_args() if not args.break_even and not args.savings_per_year and not args.savings_per_month and not args.plot: sys.exit("Please choose one or multiple options") comparator = c_ecar_comparator(args.settings) extractor = c_settings_extractor(args.settings) be_years = None be_months = None be_kilometers = None if args.break_even: be_years, be_months, be_kilometers = comparator.calculate_break_even() print("Break even after {} years and {} months.".format(be_years, be_months)) if args.savings_per_month: years = 0 months = 1 savings = comparator.calculate_costs(years, months) print("Savings per month based on yearly spending: {}.".format(round(savings[1]-savings[0], ndigits=2))) if args.savings_per_year: years = 1 months = 0 savings = comparator.calculate_costs(years, months) print("Savings per year: {}.".format(round(savings[1]-savings[0], ndigits=2))) if args.savings_per_kilometer: hundred_km = 100.0 driving = hundred_km * extractor.get_driving() / extractor.get_kilometers() labels = extractor.get_labels() print("Costs driving 100 km in the {}: {}. Costs driving 100 km in the {}: {}.".format(labels[0], round(driving[0], ndigits=2), labels[1], round(driving[1]), ndigits=2)) am_years = None am_months = None am_kilometers = None if args.amortization: am_years, am_months, am_kilometers = comparator.calculate_amortization_point() print("The electric vehicle will be amortized by savings after {} years, {} months or exactely at {} kilometres.".format(am_years, am_months, am_kilometers)) if args.plot != None: width = 0.3 plt_colors = ["#8ecae6", "#219ebc", "#023047", "#ffb703", "#fb8500"]; color_ind = 0 labels = extractor.get_labels() purchase = extractor.get_purchase() taxes = extractor.get_taxes() insurance = extractor.get_insurance() driving = extractor.get_driving() maintenance = extractor.get_maintenance() fig, ax = plt.subplots() ax.bar(labels, purchase, width, label = "Price", color = plt_colors[0]) current_y = extractor.get_purchase() y = 0 for i in range(args.plot): ax.bar(labels, taxes, width, bottom = current_y, label = "Taxes".format(y), color = plt_colors[1]) current_y = current_y + taxes ax.bar(labels, insurance, width, bottom = current_y, label = "Insurance".format(y), color = plt_colors[2]) current_y = current_y + insurance ax.bar(labels, driving, width, bottom = current_y, label = "Driving".format(y), color = plt_colors[3]) current_y = current_y + driving ax.bar(labels, maintenance, width, bottom = current_y, label = "Maintenance".format(y), color = plt_colors[4]) current_y = current_y + maintenance y += 1 labels = ["Purchase", "Taxes", "Insurance", "Driving", "Maintenance"] lnspace_start = -0.2 lnspace_stop = 1.2 lnspace_n = 10 x_text = 0.2 if args.break_even: months_a_year = 12.0 be_money = (be_years + be_months/months_a_year) * comparator.calculate_costs_a_year() be_money = be_money[1] + extractor.get_purchase() ax.plot(np.linspace(lnspace_start, lnspace_stop, lnspace_n), [be_money[1]]*lnspace_n, "--", color = plt_colors[2], label = "Break even") ax.text(x_text, be_money[1] + 100, "Break even: {} years, {} months, {} kilometers".format(be_years, be_months, be_kilometers)) labels = ["Break even"] + labels if args.amortization: months_a_year = 12.0 am_money = (am_years + am_months/months_a_year) * comparator.calculate_costs_a_year() am_money = am_money[1] + extractor.get_purchase() ax.plot(np.linspace(lnspace_start, lnspace_stop, lnspace_n), [am_money[1]]*lnspace_n, "--", color = plt_colors[2], label = "Amortization") ax.text(x_text, am_money[1] + 100, "Amortization: {} years, {} months, {} kilometers".format(am_years, am_months, am_kilometers)) labels = ["Amortization"] + labels ax.set_ylabel(extractor.get_currency()) ax.set_title("Comparision of economics: Electric vs. combustion car") ax.legend(labels) ax.grid(axis = "y") plt.show() if __name__ == "__main__": main()