As the UK is continuing to work towards is net zero goals, more homeowners have begun to consider the steps they need to take to make a carbon negative home. But what does it mean to have a carbon negative home?
A carbon-negative home is designed to produce more energy than it consumes. It follows the Passivhaus Standard, which sets specific criteria for energy efficiency and sustainability. If you live in a terraced property or have limited roof space, creating a carbon-negative home may be challenging, as you might struggle to generate enough electricity to power your home, air source heat pump, and electric car. You may find it easier start making small changes to your home, before fully committing to becoming carbon neutral then negative.
What emits carbon in the home? There are several areas of the home that can emit carbon into the atmosphere, including:
- Gas Central Heating: Gas is a fossil fuel, and when burnt, produces carbon dioxide, which is harmful to the environment.
- Poor insulation: This allows heat to escape from your home, forcing you to use more energy to keep it warm. Over time, this leads to unnecessary heat loss and higher bills.
- Fireplaces: Wood and coal are not renewable energy sources, and they both emit carbon emissions when burnt.
- Using a petrol/diesel car: Petrol and diesel are both fossil fuels, which are harmful to the environment. Their emissions are one of the biggest causes of environmental damage.
The Type of Home
Before embarking on such an extensive project, you should first review your property to ensure it is suitable. For example, an older property won’t be as heat efficient as a new build. Another consideration is whether you live in a listed property, as you will need planning permission before making significant changes with solar panels and air source heat pumps; an alternative should an ASHP not be suitable is High Efficiency Direct Electric room radiators.
How to Measure your Carbon Footprint
The first step to reducing your carbon footprint is to assess how much carbon dioxide your lifestyle is using taking in to consideration your home and personal lifestyle. Completing an assessment with organisations such as the WWF and The Nature Conservancy will highlight the areas of your lifestyle you need to adapt to become carbon negative. These could include eating less meat, sourcing food closer to your home and using alternative heating systems or renewable technologies so you’re not constantly relying on the grid.
Initial Changes
To start, you will need to review the insulation of your home, particularly in the wall cavities, roof/loft space and windows. A heat loss survey or Energy Performance Survey (EPC) can help you identify your energy efficiency and the areas of your home that require Fabric Insulation Improvements as well as recommendations on Energy Efficiency measures, such as Solar PV, ASHP’s, Smart Technology or Battery Storage (coming out in the new RDSAP Assessments).
You may have had one of these surveys already, which you can find on the Government centralised register for EPC’s, if not, Aspect Group Services can assist with an EPC assessment and undertake the required measures to help you improve your home and carbon footprint and ultimately save you money and help in the push to reduce Carbon Emissions globally.
Using an Air Source Heat Pump
An air source heat pump is an alternative heating solution that takes the outside air and converts it into energy which can heat your home, furthermore it runs on electricity, so can be powered with solar panels or powered from battery storage (which can be charged using the suns power or charged up on low rate tariffs over night and discharged at peak/expensive energy periods). There are many benefits to using heat pumps, such as:
- Renewable Heating: A heat pump operates by absorbing the natural temperature from the outside air, even in colder conditions, and through a process of of compressing this air it heats it up and generates the equivalent of 3 to 4 units of electricity in heat creating ‘high efficiency/renewable’ energy – this also means that when power the system by solar panels, it would run entirely on renewable energy. There is no detrimental impact to the environment by using a heat pump.
- Water Heating: A heat pump also heats the water, in extreme cold weather there is a back up heater to ensure you always have a nice warm shower.
- High Energy Rating: Heat pumps are termed as a renewable energy heating source due to them being 300% – 400% efficient – simply this means for every unit of electricity you use the heat pump will increase this to 3-4 units heat output.
- Quiet Running: Contrary to beliefs, heat pumps make as much noise as a fridge or a dishwasher (depending on the weather conditions), so you can continue to use your garden without disruption.
Investing in a Solar Panel System
Solar panels have grown in popularity over the years and with the SEG (Smart Export Guarantee) payments, along with the savings on your energy bill from free electricity and massive advancements in panel efficiencies, there has never been a more efficient time to install solar, especially as they are almost always vital for making a carbon negative home.
To make the most of solar energy, add battery storage to collect excess power from your panels, ensuring you have electricity even when the sun isn’t shining. Some batteries, such as Tesla Powerwall 3 include the solar inverter, which can save space. The size of the house and the current energy consumption determines how many solar panels and batteries are required to effectively power your lifestyle. Read our case study below to learn how Theo and Maddie made a carbon negative home.
What are the benefits of Solar Panels:
- Selling energy back to the grid: Creating a carbon negative home will mean you have excess energy you produce, which you can sell back to the grid for a profit.
- Power during Storms: Are you fed up of power cuts? Using Solar Panels with Battery Storage ensures there is power always ready, particularly during times of storms.
- Short Payback Period: Solar panels will not only reduce your energy bills but also offer a fast return on investment, allowing you to enjoy long-term savings.
Electric Car Impact
Investing in an electric car is an must for a achieving a carbon negative lifestyle, so consider using a home charger to benefit from solar energy. If you are making a long journey and need to recharge your car, consider using companies that use renewable energy, such as BP Pulse or Gridserve. What are the benefits of charging overnight using renewable energy:
- Overnight Charging: Charge your car overnight using battery storage and wake up ready to go. During the day, recharge directly from solar panels for a fully carbon neutral drive.
- Charging Speed Control: Optimise your charging schedule with smart controls via your car and charger apps, ensuring efficient energy use day and night.
- Choosing the Right Charger: Zappi is the world’s first solar-compatible EV charger, maximising renewable energy for a greener drive. Chargers such as the Easee One, Ohme Home and Andersen 3 all offer intelligent charging too.
Using a Electric Supplier that uses 100% Renewable Energy
By signing up with a supplier that only generates/supplies renewable energy (there are certain tariffs you can be put on) you’re ensuring the chain of carbon neutral energy is continued.
Furthermore, by using more power in off peak times, you are also reducing the grid’s dependence on non-renewable sources. Charging your battery storage or car in off peak times means you’re reducing grid spikes, and if you’re on a low rate overnight tariff, this is even more incentive to charge at a cheap rate to discharge in peak times.
Case Study: The Harris Family
Theo and Maddie, a young couple passionate about sustainability, purchased a three-bedroom property in Fakenham, Norfolk. Their goal, to make their home carbon-negative. With the help and guidance of Aspecte, they embarked on a journey to not only reduce their energy consumption but to generate more clean energy than they used.
The Challenge: High Energy Consumption
When Theo and Maddie moved into their new home, they conducted an energy audit to assess their current usage. Their household relied on a combination of gas heating and electricity from the grid, consuming an estimated 12,000 kWh of electricity and 18,000 kWh of gas annually. This resulted in an approximate carbon footprint of 5.5 tonnes of CO2 per year—a figure they were determined to eliminate.
The Solution: A Carbon-Negative Transformation
To achieve their vision, Theo and Maddie partnered with Aspecte, a leading expert in sustainable home upgrades. Together, they implemented a comprehensive plan:
Solar Panel & Battery Storage
Aspecte installed a 10kW solar PV system on their south-facing roof, generating an average of 11,500 kWh annually. To maximise efficiency, they added a home battery storage system, allowing them to store excess energy for nighttime use and cloudy days.
Heat Pump Installation
To eliminate their reliance on gas, they replaced their traditional boiler with an air source heat pump. This system efficiently provided heating and hot water while cutting their heating-related emissions to nearly zero.
Improved Insulation & Windows
To reduce heat loss, Aspecte upgraded their home’s insulation with high-performance wall and loft, underfloor and wall insulation. Additionally, they replaced old windows with triple-glazed, energy-efficient alternatives to further enhance heat retention.
With Aspecte’s guidance, Theo and Maddie integrated a smart energy monitoring system, allowing them to track real-time consumption and optimise energy use throughout the day.
EV Charger Installation
To future-proof their home, the couple also installed an EV charger, ensuring they could charge their electric vehicles with their self-generated solar power.
The Outcome: A Carbon-Negative Home
The results of their transformation were remarkable:
- Electricity generation exceeded their annual consumption, enabling them to export excess power back to the grid.
- Their gas usage was eliminated, removing a major source of emissions.
- Their home’s carbon footprint dropped below zero, making them net contributors of clean energy.
- Not only did these upgrades make Theo and Maddie’s home more sustainable, but they also led to significant savings on energy bills, with an estimated reduction of £1,800 per year.
- It’s also important to consider and allow for ventilation/air change in a well insulated building to ensure good quality air within the home.
Additional Steps
Making a house carbon negative has a hugely positive impact on both the environment and homeowners. However, achieving this goal involves multiple steps, which is where we come in. At Aspecte, we are leading experts in solar energy, air source heat pumps, and EV charger installations and understand the key considerations when making such a significant change. Contact our team today and start your journey to a carbon-negative home.
