The Content Coms Guide to… The Sixth Carbon Budget

Last week the Committee on Climate Change (CCC) published The Sixth Carbon Budget, required under the Climate Change Act, to provide ministers with advice on the volume of greenhouse gases the UK can emit during the period 2033-2037.

It charts the decisive move to zero carbon for the UK, and shows that polluting emissions must fall by almost 80% by 2035, compared to 1990 levels. This is a big step-up in ambition – just 18 months ago this was the UK’s 2050 goal.

The CCC believes the Sixth Carbon Budget can be met through four key steps:

• Take up of low-carbon solutions.
• Expansion of low-carbon energy supplies.
• Reducing demand for carbon-intensive activities.
• Land and greenhouse gas removals.

The message to Government is clear: the 2020s must be the decisive decade of progress and action on climate change. But what impact is it going to have on the built environment?

The CCC’s pathways to 2050 aim to reduce emissions in buildings to zero by 2050 at the latest and to ensure buildings of the future are comfortable, healthy spaces to be year-round, which are resilient to overheating and other climate risks.

Currently…

• Buildings account for 23% of UK total greenhouse gas emissions. 17% of this is burning fossil fuels for heating (direct emissions), the rest is electricity (indirect emissions) for services such as lighting, cooling, ICT equipment.
• Of the direct building emissions these are split between homes (77%), commercial buildings (14%) and public buildings (9%).
• Of the indirect building emissions, buildings are responsible for 59% of UK electricity consumption, equivalent to a further 31 MtCO₂e of indirect emissions

To achieve its goals, the CCC has identified four key priorities over the next ten years:

• Deliver on the Government’s energy efficiency plans to upgrade all buildings to EPC C over the next 10 to 15 years.
• Scale up the market for heat pumps as a critical technology for decarbonising space heating, while maintaining quality.
• Expand the rollout of low-carbon heat networks in heat dense areas like cities, using anchor loads such as hospitals and schools. Prepare to shift away from using fossil fuel Combined Heat and Power (CHP) as a supply source towards low-carbon and waste heat by preference from the mid 2020s.
• Prepare for a potential role for hydrogen in heat through a set of trials building on the current innovation programme.

To meet the key priorities, the CCC has set out some key dates which will help reduce carbon emissions from the built environment. 

• By 2025
  • All new buildings to be zero carbon by 2025 at the latest. This means high levels of efficiency and low carbon heating.
  • CHP phase out for new low-carbon district heat. Currently, around 93% of district heat networks use a fossil fuel based. Legacy CHP schemes should be converted to low carbon sources by 2040.
  • All new boilers to be hydrogen ready.
• By 2028
  • 100% of heating system sales off the gas grid to be low carbon
• By 2030
  • 37% of public and commercial heat demand is met by low-carbon sources. Of this low-carbon heat demand 65% is met by heat pumps, 32% district heating and 3% biomass. By 2050 all heat demand is met by low-carbon sources of which 52% is heat pumps, 42% is district heat, 5% is hydrogen boilers and around 1% is new direct electric heating.
  • All commercial energy efficiency renovations to be completed by 2030.
• By 2033
  • Gas grid phase out – 100% of heating system sales are low-carbon, with an earlier date of 2030 set for public buildings so as to achieve the Clean Growth Strategy Target of 50% emission reduction by 2032.

The Balanced Pathway requires investment across all buildings at an average rate of around £12 billion per year to 2050, offset by reductions in operating costs of £5 billion per year.

• Total investment costs are £360 billion to 2050, of which around £250 billion is for the programme of upgrading homes and £110 billion in public and commercial buildings.
• The deployment of all energy efficiency potential in public and commercial buildings entails £2 billion per year of commercial investment to 2030 and £0.5 billion per year of public sector investment to 2032. Annual operating cost savings of around £1.5 billion and £0.5 billion result for commercial and public buildings respectively.
• Including low-carbon heat increases this to £2.8 billion per year investment in commercial buildings and £0.9 billion in public buildings through the 2030s and 2040s. This is associated with total operating cost savings of £3 billion per year across public and commercial buildings.

The Sixth Carbon Budget must be legislated by June 2021. The full report can be read here.