I usually write about emissions on the grid. This is about the ones in my kitchen.
Three weeks ago I put an air quality monitor in there. It measures CO2, particulates, volatile organic compounds, humidity and, because we live on Dartmoor granite, radon. I already log the house's electricity every ten seconds. So when the in-laws came for Sunday lunch on 27 September, the roast was the best-instrumented meal I have ever cooked. The one sensor missing from the record is the one that was actually in the chicken: the Meater probe talks to my phone, not to Home Assistant.
I had a plan for it, too.
The plan
Our house is all-electric. There is no gas hob, no gas oven and no boiler: a heat pump, an induction hob, an electric oven and two electric cars. Every unit of energy that goes into a meal comes off the grid, which means I can choose how dirty that energy is by choosing when I cook.
So: chicken, not beef. Lunch, not dinner. The oven went on at about half past eleven, into a South West grid that was sliding from 150 grams of CO2 per kilowatt-hour towards its low for the day. It was a blustery Sunday, with wind supplying a quarter of the region's power, and when the sun finally came out after one o'clock the grid dropped to 70 g/kWh at half past two.
It worked. The kitchen used 6.5 kWh between eleven and half past three, at an average of 112 g/kWh. Call it 0.7 kg of CO2. The same cooking at that evening's 297 g/kWh would have been 1.9 kg. (Autumn is a good time to try this: there is still enough sun to dig a hole in the middle of the day.)