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README.md

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 # EconomicsOfAnElectricVehicle
 
-Small script, that allows to do the back of the napkin math if an electric vehicle is cheaper than a combustion car. 
+Is driving an EV really cheaper like everybody keeps telling you? Frank answer: it depends! This script allows to set the (from my humble point of view) relevant variables and calculate. 
+
+## General usage
+
+```
+usage: ecar.py [-h] -a FILENAME [-b] [-c] [-d] [-e] [-f] [-g YEARS]
+
+This script allows to calculate if an electric car makes sense financially for you.
+
+optional arguments:
+  -h, --help            show this help message and exit
+  -a FILENAME, --settings FILENAME
+                        Settings file.
+  -b, --break_even      Calculate the break even point (when the EV becomes cheaper).
+  -c, --amortization    Calculate the point in time when the electric vehicle is amortized completely by savings.
+  -d, --savings_per_month
+                        Calculate savings per month.
+  -e, --savings_per_year
+                        Calculate savings per year.
+  -f, --savings_per_kilometer
+                        Calculate savings per 100 kilometers (only driving, no maintenance, taxes or insurance).
+  -g YEARS, --plot YEARS
+                        Visualize costs over one or multiple years.
+```
+
+Important milestones the script allows to calculate depending on personal driving patterns are:
+* **Break even**: When you need to decide whether you buy an electric car or a combustion car.
+* **Point of amortization**: When you have a workhorse car (like me), that is not replacable by any affordable electrical drive train technology, this shows when the investment is fully amortized by savings when not using your combustion car.
+
+## Example
+The plot below can be generated with 
+
+```
+python3 ecar.py --settings ecar.json -b -c -d -e -f --plot 3
+```
+
+This will also lead to the following output
+
+```
+Break even after 0.0 years and 3.0 months.
+Savings per month based on yearly spending: 279.83.
+Savings per year: 3358.0.
+Costs driving 100 km in the Nissan Leaf 2013: 3.5. Costs driving 100 km in the Suzuki Grand Vitara 2008: 14.
+The electric vehicle will be amortized by savings after 2.0 years, 4.0 months or exactely at 45265.04 kilometres.
+```
+
+![Example 0](https://git.stiefel.tech/m3x1m0m/EconomicsOfAnElectricVehicle/raw/branch/master/pictures/plot_ex_0.png)