The UK has enacted a legally binding target to reduce its carbon emissions to net zero by 2050. Insulating homes decreases the amount of fuel needed to heat them, reducing carbon emissions. Increasing the number of insulation measures installed is necessary if the UK is to meet its target.
Carbon emissions resulting from heating homes must be reduced. Insulation decreases the amount of heat lost through roofs, walls, and floors, meaning less energy is required to heat a building.
The Government runs schemes to encourage the uptake of insulation measures, but installation rates have fallen significantly since 2012. The Committee on Climate Change and the House of Commons Business, Energy and Industrial Strategy Committee have argued that the Government should implement new measures to increase the amount of insulation being installed.
The amount of carbon dioxide emissions permitted over a period of time to keep within a certain temperature threshold – have grown in importance in the climate change debate in recent years.
To inform policy and measure progress towards the target, the UK sets five-yearly carbon budgets. A carbon budget places a restriction on the total amount of greenhouse gases the UK can emit. Budgets up to the fifth carbon budget, covering 2028–32, have been set. The fifth carbon budget would limit annual emissions to an average 57% below 1990 levels.
It is clear from the science that the amount of carbon dioxide (CO2) in the atmosphere as a result of human activity largely determines the extent of global warming. This means that to prevent catastrophic climate change, CO2 emissions need to be reduced to zero. The science led to governments worldwide agreeing to achieve a balance between emissions and removal of greenhouses gases, in the Paris Agreement
NET ZERO TARGET
The UK has enacted a legally binding target to reduce its carbon emissions by 100% of 1990 levels by 2050. This is known as the net zero target, because the legislation allows the UK to offset any emissions in excess of 1990 levels by purchasing carbon credits. The net zero target replaced the previous target of reducing the UK’s emissions by 80% of 1990 levels by 2050.
‘Net zero’ refers to achieving an overall balance between emissions produced and emissions taken out of the atmosphere. Like a bath with the taps on, an approach to achieving this balance can either be to turn down the taps (the emissions) or to drain an equal amount down the plug (removals of emissions from the atmosphere, including storage for the emissions such as ‘carbon sinks’).
In contrast to a gross-zero target, which would reduce emissions from all sources uniformly to zero, a net-zero emissions target is more realistic because it allows for some residual emissions.
This takes into account that some emissions are produced by ‘hard-to-treat’ sectors, such as aviation and manufacturing, where reducing emissions is either too expensive, technologically too complex or simply not possible.
In a net-zero scenario the residual emissions from these sectors are allowed as long as they are offset by removing emissions using natural or engineered sinks – gross negative emissions.
The timing of the net-zero target that will be announced by the Committee on Climate Change is the final key element. Four options have been considered: 2025, 2045, 2050 and any time thereafter.
A target date of 2045 would match the ambition of Sweden and Norway, and, through setting a stringent target, demonstrate leadership on the international stage. This would promote the UK as a global forerunner for international diplomacy on climate change. However, it is also important to recognise that the UK is not even on track to hit its 4th or 5th carbon budgets, so expediting the target date while simultaneously increasing ambition seems unlikely to happen.
All these factors considered, the most realistic target is likely to be 2050, as the Financial Times has now alluded to. Further, this would require no change in primary legislation or formal revision of the 2008 Climate Change Act, whereas any deviation from 2050 is likely to necessitate the proposal of a new Bill or Act.
REDUCING ENERGY USE IN HOMES
Energy use in homes accounts for about 14 percent of UK greenhouse gas emissions, according to the Committee on Climate Change (CCC).
The majority of energy used in homes, 63%, is for space heating. Insulation reduces the amount of heat lost through walls, roofs and floors, meaning that less energy is required to heat a building.
The CCC argues that “near-complete” decarbonisation of how we heat our homes would be required for the UK to meet its emission reduction targets. This can be achieved through changing to cleaner fuels and reducing the amount of energy required.
CURRENT STATE OF INSUALTION OF THE NATION’S HOMES
At the end of 2019, 70% of homes with a cavity wall had cavity wall insulation (14.1 million properties), 66% of homes with a loft had loft insulation (16.4 million properties) and 9% of homes with solid walls had solid wall insulation (764,000 properties).
In 2017, carbon emissions from homes were 9% below 1990 levels. When adjusting for annual temperature variation, emissions from homes rose by 1% in 2017.
HOW HAVE INSULATION RATES PROGRESSED OVER TIME?
Rates of energy efficiency measures being installed have fallen in recent years. Figure 1 shows the number of insulation measures installed in homes under government schemes between 2008 and 2017.
Eco and Green Deal
The energy company obligation (Eco) and green deal are Government energy efficiency schemes, which began in 2013. They replaced the previous energy efficiency schemes: the carbon emissions reduction target, community energy saving programme and warm front. Their aim is to improve the efficiency of the country’s homes by encouraging the uptake of energy efficiency measures through grants, loans, and subsidies.
The Government has a target to upgrade around one million homes through Eco and other Government domestic energy efficiency schemes. The target covers a five-year period, from the start of May 2015 to the end of April 2020. As of December 2019, around 963,900 homes had at least one improvement measure installed under Eco or the green deal.
Clean Growth Strategy
The Clean Growth Strategy sets out the Government’s policies aimed at increasing economic growth and decreasing carbon emissions. The strategy includes measures to bring emissions within those set out in the UK’s fifth carbon budget, covering the period 2028–32.
In the strategy, the Government says that one “possible pathway” to achieving its emissions reduction goal for 2032 involves emissions from homes falling by almost one fifth compared to 2017 levels. This pathway could see a further six to nine million properties insulated. The Government says that “more broadly, our aspiration is that as many homes as possible are improved to EPC [energy performance certificate] Band C by 2035, where practical, cost-effective and affodable”
In its 2019 report on energy efficiency in buildings, the House of Commons Business, Energy and Industrial Strategy Committee criticised the Government for not defining “where practical, cost-effective and affordable” and for not putting in place a measurable target for this ambition.
House of Commons Business, Energy and Industrial Strategy Committee
The House of Commons Business, Energy and Industrial Strategy Committee highlights various factors that hinder the take-up of energy efficiency measures, including:
- high upfront costs;
- long-term returns;
- split incentives between landlords and tenants;
- the ‘hassle’ of retrofit works; and
- a perception that energy efficiency investment is not captured by property prices.
It concludes that because of these obstacles, Government should intervene in the following ways:
- As fuel poor or low-income households are often not able to pay for energy efficiency measures, these costs should be covered by public investment to a significant or full extent.
- A combination of central government funding and social landlord investment should pay for energy efficiency in the social-rented sector.
- Better off households and private landlords should, where possible, pay for energy efficiency improvements themselves. However, because not all benefits of energy efficiency are reflected in market prices, incentives and regulation are needed to induce ‘able to pay’ property owners to invest.
Committee on Climate Change
The Committee on Climate Change’s scenarios for meeting the fifth carbon budget require insulation of about 7.5 million more walls and lofts from the number recorded in 2015.
The CCC argues that in many areas current policy is failing to drive uptake of energy efficiency measures in homes, including for highly cost-effective measures such as loft insulation. The CCC states that the uptake of energy efficiency measures such as loft and wall insulation must be increased, and that “policy needs to incentivise efficient long-term investments, rather than piecemeal incremental change”.
- House of Commons Library, Net Zero in the UK, 16 December 2019.
- House of Commons Library, UK Carbon Budgets, 9 July 2019
- Committee on Climate Change, UK Housing: Fit for the Future?, 21 February 2019