Retrieving my electricity usage with the Octopus Energy API using Python 🐙

I’ve recently changed my energy supplier to Octopus……the main reason being their super-cheap overnight electricity rates, which will save me lots of money charging my EV car 💷.

I noticed that they had a developer API, ever the tinkerer I thought I’d take a closer look. Their documentation is really extensive, however their examples all used Curl and I wanted to have a play with Python (using the Requests module). I ran into a couple of issues so thought I’d document this to help others (although most likely my future self when I forgot all of this 😂)

Issue 1 – authenticating to the API using a key

The API uses HTTP basic auth (which uses a key that is available on the API access page), after much searching I found the equivalent for the -u parameter in Curl to enable me to successfully authenticate using the key. The trick was import HTTPBasicAuth using the following command:

from requests.auth import HTTPBasicAuth

Then when making the request to the API using the following syntax, which passes the API key (key variable) and the username, with a blank password (denoted by “”).

request = requests.get(url,auth=HTTPBasicAuth(key,""))

Issue 2 – formatting the date for period_from correctly

The API allows you to pass it a period_from parameter, this is useful to get your energy consumption from a specific date. In my specific use-case, I wanted to see my consumption from the previous 7 days. I achieved this using the following:

date7daysago = (datetime.datetime.now() - datetime.timedelta(days=7)).isoformat()

Pulling all of this together, I created the script below which connects to the developer API and retrieves my electricity consumption for the previous 7 days (grouped by day) and outputs this to the console – if you’d like to use this you’ll need to update the key, MPAN and serial variables – all of which are listed on this page (if you are a customer of course!)

import requests
from requests.auth import HTTPBasicAuth
import datetime
date7daysago = (datetime.datetime.now() - datetime.timedelta(days=7)).isoformat() # calculate the date 7 days ago
key = "KEY"
MPAN = "MPAN"
serial = "SERIAL"
baseurl = "https://api.octopus.energy/v1/"
url = baseurl + "electricity-meter-points/" + MPAN + "/meters/" + serial + "/consumption" + "?period_from=" + date7daysago + "&group_by=" + "day"
request = requests.get(url,auth=HTTPBasicAuth(key,""))
request.json()

Here is the output of the script – you may notice that it doesn’t include 7 days worth of data, that is because I haven’t been a customer for that long.

To make it a little easier to read I added the following to the script, which prints out the date and consumption:

consumption = request.json()
for result in consumption["results"]:
    print(str(result["interval_start"].split("T")[0]) + " : " + str(result["consumption"]))

Based on my previous escapades with developer API’s for consumer services I’m sure that I’ll be writing an Alexa skill for this next 🤖.