My House

So far we have reduced carbon emissions from gas and electricity from approximately 3.7 tonnes to around 0.7 tonnes, a reduction of 80% with no loss of quality of life – in fact the house is warmer now!

I am on a mission to reduce the carbon dioxide emissions from my house, ideally to zero.

This page contains links – see below – to all the articles I have written on this project over the last few years. Some more recent articles also include videos.

If you have any questions or would like to comment, e-mail me here.

Summary

• I began by taking weekly measurements of:
  • gas and electricity consumption.
  • outside temperature.
• This allowed me to assess how my house ‘performed’ i.e. how much heating I needed to provide to heat the house a certain number of degrees above the outside temperature.
• In Autumn 2019 I added some triple-glazing.
  • In the winter of 2019/20 I could see 10% improvement in the performance of the house.
• In Autumn 2020 I finished the triple-glazing and added external wall insulation.
  • In the winter of 2020/21 the house only required half the energy it had in 2019.
• In November 2020 I added solar panels and in March 2021 I added a domestic battery
  • Since March 2021 we have been mostly ‘off-grid’.
  • In the winter of 2021/22 we expect to buy electricity at night and use it during the day.
• In July 2021 I removed the gas boiler and added a heat pump.

I’ll be updating this intermittently, but this household project is (I hope!) almost complete.

Articles about the House on Protons for Breakfast

2022

• Analysis of 16 years of Solar PV data.  (16th March)
  • A review of the 16 year’s of solar data from a house in North London.
• Heating Degree Days (15th March)
  • Four articles on their incredibly useful idea!
  • Heating Degree Days:1:
    • A brilliant idea
  • Heating Degree Days:2:
    • Do they work?
  • Heating Degree Days:3:
    • How do they vary?
  • Heating Degree Days:4:
    • Three numbers you need to know about your home
• Another reason to stop using gas (6th March)
  • Cooking with gas emits more NOX into your home than traffic fumes!
• Heat Pump Explainer (24th February)
  • Everyone is talking about heat pumps. But how do they work?

• Reducing CO2 Emissions from my home (4th February)
  • A talk I gave to the local Friends of the Earth

• Carbon accounts 2021: looking back and looking ahead (2nd January)
  • A review of how the reductions in CO2 are going.

2021

• November 2021: Heating and Carbon Emissions (1st December)
• A summary of the way all the elements of our retrofit work together in November.
  • Insulation reduced heat demand by half
  • Solar PV met 20% of our electricity demand.
  • Battery allowed time-shifting, avoiding peak rate electricity
  • Air source heat pump operated with more than 300% efficiency
• The Role of a Battery in Meeting Winter Electricity Demand(26th November)
  • Details of how Solar PV with a battery saves emissions even in winter.
• A weekend away… (15th November)
  • An article about Weather Compensation with Heat Pumps
• A Year of Solar Energy (8th November)
  • Review of a year of solar energy data
• Heat Pump Operation: What it costs. And what it costs me (26th October)
  • Details of what I actually pay to heat my home: almost nothing
• Heat Pump Operation: First Space-Heating Results (25th October)
• 1000 days of data  (9th October)
  • A review of the last three years of thermal data on the house.
• Controlling Tap Temperatures with a Blending Valve (October 6th)
  • How to keep tap water temperatures safe even when the hot water cylinder is very hot.

• Carbonaut (6th October)
  • Includes videos of a talk describing the entire carbon zero project.
• Legionella Protection with Heat Pumps (October 1st)
  • Why Heat Pump systems need to worry about Legionella and what to do.
• Using Radiators with Heat Pumps (9th September)
  • How radiators work and all that.
• Assessment of Heat Pump heating water to 50 °C and 70 °C (14st August)
  • Looking at the COP of the heat pump when it gets very hot!
• Heat Pumps: Power, Noise and Condensation (31st August)
  • How heat pumps work, why they are quiet, and how much condensation to expect.
• Heat Pump – First Operational Data (14st August)
  • Dat showing how the COP of our heat pump is measured.
• Our Old Car is Dead. Long Live The New Car! (July 28th)
  • Why we didn’t buy an EV.
• Back Down to Earth (June 22nd)
  • Sometimes it just isn’t sunny – even at midsummer!
• Floating  (June 16th)
  • Reflections on a few days of using no gas and grid electricity: entirely solar powered!
• Boiler Killer Strikes Again (June 10th)
  • A piece of nonsense.
• Heat Pumps#1 (June 10th)
  • An article about how heat pumps work in a domestic setting.
• Estimating Rates of Air Change in Homes (June 6th)
  • How to use  CO2 meter to estimate the rate of air changes in homes.
• Gas Boilers versus Heat pumps (May 18th)
  • Why gas boilers are still right answer in some circumstances.
• Air Conditioning versus Air Source Heat Pump (May 15th)
  • Why Air Conditioning might be able to heat our hose with a higher COP than a heat pump.
• My Energy Performance Certificate (21st April)
  • What does the EPC even mean?
• Battery Day: One month on… (20th April)
  • Performance of the Tesla Powerwall domestic battery. Wow!
• Battery Day. One week on… (24th March)
  • Performance of the Tesla Powerwall domestic battery. Wow!
• Battery Day: First Results (20th March)
  • Performance of the Tesla Powerwall domestic battery. Wow!
• Understanding heat flow in my home: the key graph (15th February)
• Domestic Batteries: Purchase Decisions and Realistic Models (1st February)
• In the Bleak Mid-Winter (19th January)
• Domestic Batteries: Thinking More about Batteries (9th January)
• Domestic Batteries: Thinking about Domestic Batteries (3rd January)
• External Wall Insulation: Day-by-Day Analysis (1st January)

2020

• External wall insulation: How well is it working? (23rd December) after a month or so
• External Wall Insulation: How well does it work? (16th November) just after installation.
• The Beginning of the External Wall Insulation Project (15th October)
• Passivhaus? Or Michaelhaus? (August 26th)
• Measuring the thermal conductivity of insulation (August 24th)
• I am becoming an insulation bore. (August 21st)
• My House: comparing models and measurements (July 28th)
• Estimating the expected thermal performance of my house (July 22nd)
• Be Constructive! (July 5th)
• House of Shame#1 (June 24th)

2019

• The OTHER front in the fight against climate change (September 22nd)
• Why does heating my house require 280 watts per degree Celsius above ambient? (August 18th)
• What it takes to heat my house: 280 watts per degree Celsius above ambient (August 16th)
• Should I still be using gas? (May 6th)