How to decarbonise your home part 2
Journal part 2
Follow the journey of two climate and energy experts as they decarbonise their home.
As it involves their private life, we’re withholding their identities.
What happens if we turn the underfloor heating off?
I wrote last time about our beloved underfloor heating in the kitchen and how it was costing us a fortune in both hard cash and carbon emissions. I suddenly understood all those people who say ‘but I don’t want climate change to inconvenience me’ because I felt the same way about my floor. My son lies on it, searching out the warm spots on his belly like a lizard with a heat lamp. I sit on it to play with him, or lie full length on it after I’ve worked in the garden and done my back in. My husband has a skin condition which means he struggles to retain heat. For him to be able to walk into a nice warm room is important.
But it had to go as our electricity consumption was reaching 50 kWh per day.
I still hadn’t figured out the operating system and found time to re-programme it, but I had managed to switch it from Fahrenheit to Celsius. We decided to try just having the floor on in the morning between getting up and going to work and in the evening when we would be home from work and cooking and eating dinner. This was a great plan in theory but what it took us a few weeks to figure out was that the electricity required to get the floor up to temperature was actually quite high. The electricity required to keep it at a comfortable temperature was comparatively low. So we spent a whole month still using about 30 kWh per day just having the floor switched on for about 6 hours per day. Finally we reached the compromise of just putting the floor on at the weekend and switching it off during the week. This led to a rise in our gas consumption because I would add an hour onto the gas central heating during the week to compensate for the lack of electric floor heating. We also found that we spent less time in the kitchen and my boy was generally sad during the week because we’d switched off ‘floory’.
I have to say that when I started on this idea of blogging about decarbonising my home I’d anticipated writing glowing accounts of major decisions that we’d spent and builders that we’d got in to make substantial changes to our house. It’s not going to turn out like that at all!
How much gas do we use?
Back to our gas consumption: from daily meter readings I’d discovered that our daily heating and my husband’s shower added up to approximately 3 m3 of gas per day. The boy has about three shallow baths a week and I shower twice or three times a week, which puts it up to 4 m3 a day, as we coincidentally wash on the same day. For a family of three in a fairly large house this is on the very conservative side of gas usage. So I was hoping that when my friend crunched our CO2 numbers it would come out in favour of us buying some nice shiny solar panels for the roof. Buying solar panels seems like a nice safe eco-friendly option. It’s an established technology, it’s socially acceptable and seen as the go-to move for people who say they love the planet, it’s also easy to understand: panels go on the roof, electricity cables are attached, sunlight hits the panel, electricity runs things in the house and the excess goes to the grid. That seems much more simple than say, a ground source or air source heat pump which usually people explain to me as ‘oh it’s a fridge in reverse’ which doesn’t help at all because I don’t really know how my fridge works!
However, the numbers came back and actually it was our car that was the highest emitter, even with my electricity-sucking electric floor! We drove 5,300 miles last year and own a Mondeo estate car (bought 3 years ago for the massive boot/trunk which happily swallowed the myriad of equipment one requires for a baby). My friend assumed that this would be 417 miles a month (average) and that the car would do 40 miles to the gallon. This gives a monthly emission of 134 kg CO2e. Whilst our January electricity emissions were double that at 285 kg CO2e they would drop dramatically in the Summer months to a guesstimated 60 kg CO2e which would be far less than the car. Based on the guesstimates my friend calculates that we would save 1,274 kg CO2e from switching our car to an electric car and 900 kg CO2e by installing photovoltaics.
The decarbonisation guru had spoken and I have to admit I was slightly disappointed. Changing cars seemed really difficult. Not only would we have to install a charging point on our house = builders banging, we’d also have to negotiate charging points on long-distance journeys. The solar panels felt easier. However, taking the easy option isn’t always the correct option, so car discussions are taking place!